WO2015104986A1

WO2015104986A1 - Film-like adhesive, dicing tape with film-like adhesive, method for manufacturing semiconductor device, and semiconductor device

Info

Publication number: WO2015104986A1
Application number: PCT/JP2014/083896
Authority: WO
Inventors: 悠樹菅生; 謙司大西; 木村　雄大
Original assignee: 日東電工株式会社
Priority date: 2014-01-08
Filing date: 2014-12-22
Publication date: 2015-07-16
Also published as: KR20160106625A; TW201533213A; CN105899629A

Abstract

Provided are: a film-like adhesive having excellent conductivity; and a dicing tape with a film-like adhesive. The present invention relates to a film-like adhesive which contains conductive particles having a specific shape. Examples of the conductive particles include gold particles, silver particles, copper particles and coated particles. Each of the coated particles is provided with a core particle and a coating film that covers the core particle. Examples of the material of the coating film include gold, silver and copper.

Description

Film adhesive, dicing tape with film adhesive, semiconductor device manufacturing method, and semiconductor device

The present invention relates to a film adhesive, a dicing tape with a film adhesive, a method for manufacturing a semiconductor device, and a semiconductor device.

In the manufacture of semiconductor devices, a method of bonding a semiconductor element to a metal lead frame or the like (so-called die bonding method) has been changed from a conventional gold-silicon eutectic method to a solder or resin paste method. At present, a method using a conductive resin paste is used.

However, the method using a resin paste has a problem that the conductivity is reduced by voids, the thickness of the resin paste is non-uniform, and the pad is contaminated by the protrusion of the resin paste. In order to solve these problems, a film-like adhesive containing a polyimide resin may be used instead of the resin paste (see, for example, Patent Document 1).

On the other hand, power semiconductor devices are expected to grow in the recent semiconductor device market. In a power semiconductor device, high electrical conductivity is required for an element bonding material.

Japanese Patent Application Laid-Open No. 6-145639

An object of the first and second aspects of the present invention is to solve the above-described problems and provide a film-like adhesive excellent in conductivity and a dicing tape with a film-like adhesive.

1st this invention contains electroconductive particle, electroconductive particle is at least 1 sort (s) selected from the group which consists of gold particle, silver particle, copper particle | grains, and covering particle | grains, and covering particle | grains are core particle | grains and a core particle | grain. A coating film that covers the particles, the coating film includes at least one selected from the group consisting of gold, silver, and copper, and the conductive particles include plate-like particles having an aspect ratio of 5 or more, The present invention relates to a film adhesive in which the content of plate-like particles in 100% by weight of conductive particles is 5% to 100% by weight.

When only spherical particles are blended, a conductive path is formed by point contact between the spherical particles. On the other hand, in the film-like adhesive according to the first aspect of the present invention, the plate-like particles are brought into surface contact to form a conductive path. Therefore, superior conductivity can be obtained as compared with an adhesive containing only spherical particles.

Moreover, since plate-shaped particle | grains contain gold | metal | money, silver, copper, etc., the outstanding electroconductivity is acquired.

2nd this invention contains electroconductive particle, electroconductive particle is at least 1 sort (s) selected from the group which consists of gold particle, silver particle, copper particle | grains, and covering particle | grains, and covering particle | grains are core particle | grains and a core particle | grain. A coating film for coating the particles, the coating film including at least one selected from the group consisting of gold, silver, and copper; and the conductive particles include spherical spherical particles, and the particle size distribution of the spherical particles , There are two or more peaks, peak A exists in the particle size range of 0.2 μm to 0.8 μm, peak B exists in the particle size range of 3 μm to 15 μm, and peak A of the particle size of peak B The present invention relates to a film adhesive having a ratio of 5 to 15 relative to the particle size.

In the film-like adhesive of the second aspect of the present invention, since spherical particles forming the peak A are filled between the spherical particles forming the peak B (gap), many contact points between the spherical particles are formed. . Therefore, excellent conductivity can be obtained.

Moreover, since the spherical particles contain gold, silver, copper, etc., excellent conductivity can be obtained.

The film adhesive is preferably obtained by a solvent coating method. This is because the thickness uniformity is excellent.

The film adhesive preferably contains a curable resin. Thereby, thermal stability can be improved.

The content of conductive particles in the film adhesive is preferably 30% to 95% by weight. If it is less than 30% by weight, it tends to be difficult to form a conductive path. On the other hand, when it exceeds 95% by weight, it tends to be difficult to form a film. In addition, the adhesion to the wafer tends to decrease.

The volume resistivity of the film adhesive is preferably 1 × 10 ⁻⁶ Ω · m or more and 9 × 10 ⁻² Ω · m or less. This is because it has good conductivity and can be applied well to small and high-density mounting.

The thickness of the film adhesive is preferably 5 μm to 100 μm. Thereby, the adhesion area with a semiconductor wafer etc. is stabilized. Moreover, the protrusion of the film adhesive can be suppressed.

The film adhesive is preferably used as a die attach film.

The first and second aspects of the present invention also relate to a dicing tape with a film adhesive comprising a dicing tape and a film adhesive laminated on the dicing tape.

It is preferable that when the film adhesive is peeled off from the dicing tape under the conditions of a peeling temperature of 25 ° C. and a peeling speed of 300 mm / min, the peeling force is 0.01 N / 20 mm to 3.00 N / 20 mm. As a result, chip skipping can be prevented and pickup can be performed well.

The first and second aspects of the present invention also relate to a method for manufacturing a semiconductor device including a step of die-attaching a semiconductor chip to an adherend using a film adhesive.

The first and second aspects of the present invention also relate to a semiconductor device.

When the film adhesive is adhered to the substrate, a void may enter between the film adhesive and the substrate. When a void exists between the film-like adhesive and the substrate, since the area where the film-like adhesive contacts the substrate is small, conductivity is low.

3rd this invention solves the said subject, can eliminate the void which exists between an electroconductive film adhesive and an adherend, and an electroconductive film adhesive contacts an adherend. It aims at providing the manufacturing method of the film adhesive which can ensure an area, the dicing tape with a film adhesive, and a semiconductor device.

According to a third aspect of the present invention, there is provided a conductive film adhesive after a step of die-bonding a semiconductor chip on an adherend and a step of die-bonding the semiconductor chip on an adherend via a conductive film-like adhesive. The present invention relates to a conductive film adhesive for use in a method for manufacturing a semiconductor device including a step of thermosetting by heating under pressure.

The conductive film adhesive of the third aspect of the present invention usually contains conductive particles. It is preferable that the content of conductive particles in the conductive film adhesive of the third aspect of the present invention is 30% by weight to 95% by weight. If it is less than 30% by weight, it tends to be difficult to form a conductive path. On the other hand, when it exceeds 95% by weight, it tends to be difficult to form a film. Moreover, there exists a tendency for the adhesive force with respect to a metal layer to fall.

The conductive particles are preferably at least one selected from the group consisting of gold particles, silver particles, copper particles, and coated particles because of its excellent conductivity. The coated particle includes a core particle and a coating film that coats the core particle. The coating film preferably contains at least one selected from the group consisting of gold, silver and copper.

The conductive particles preferably include plate-like particles having an aspect ratio of 5 or more, and the content of the plate-like particles in 100% by weight of the conductive particles is preferably 5% by weight to 100% by weight.

In a conductive film adhesive containing plate-like particles, a conductive path is formed when the plate-like particles are in surface contact with each other. On the other hand, when only spherical particles are blended, a conductive path is formed by point contact between the spherical particles. Therefore, the conductive film-like adhesive containing plate-like particles can have superior conductivity compared to the adhesive containing only spherical particles.

The conductive particles preferably include spherical spherical particles. In the particle size distribution of spherical particles, there are two or more peaks, peak A exists in the particle size range of 0.2 μm to 0.8 μm, peak B exists in the particle size range of 3 μm to 15 μm, The ratio of the particle diameter to the particle diameter of peak A is preferably 5-15.

In the conductive film adhesive having the peak A and the peak B in the particle size distribution, the spherical particles forming the peak A are filled between the spherical particles forming the peak B (gap). Many contact points are formed. Therefore, excellent conductivity can be obtained.

The third aspect of the present invention also provides a conductive film adhesive after the steps of die-bonding the semiconductor chip on the adherend and the steps of die-bonding the semiconductor chip on the adherend via the conductive film adhesive. The manufacturing method of a semiconductor device including the process of thermosetting by heating an agent under pressure.

By thermally curing the conductive film adhesive under pressure, voids existing between the conductive film adhesive and the adherend can be eliminated, and the conductive film adhesive is deposited. The area that contacts the body can be secured. Therefore, a semiconductor device in which electricity easily flows between the semiconductor chip and the adherend can be manufactured.

In the step of thermally curing the conductive film adhesive, it is preferable to heat under a pressure of 0.5 kg / cm ² to 20 kg / cm ² . In the step of thermally curing the conductive film adhesive, it is preferable to heat within the range of 80 ° C to 260 ° C. Further, it is preferable to heat within the range of 0.1 hour to 24 hours.

The third aspect of the present invention also relates to a dicing tape and a dicing tape with a film adhesive provided with a conductive film adhesive disposed on the dicing tape.
The dicing tape with a film adhesive of the third aspect of the present invention is disposed on the conductive film adhesive and the step of disposing the semiconductor wafer on the conductive film adhesive of the dicing tape with the film adhesive. A step of dicing a semiconductor wafer to form a semiconductor chip, a step of picking up the semiconductor chip together with a conductive film adhesive, and a step of die bonding the semiconductor chip onto the adherend via the conductive film adhesive And after the step of die-bonding the semiconductor chip on the adherend, the step of thermally curing the conductive film adhesive by heating under pressure is used.

The third aspect of the present invention also includes a step of preparing a dicing tape with a film adhesive, a step of placing a semiconductor wafer on the conductive film adhesive of the dicing tape with a film adhesive, and a conductive film adhesive. A step of dicing a semiconductor wafer placed on the agent to form a semiconductor chip, a step of picking up the semiconductor chip together with the conductive film adhesive, and attaching the semiconductor chip via the conductive film adhesive The present invention relates to a method for manufacturing a semiconductor device including a step of die-bonding on a body and a step of thermally curing a conductive film adhesive by heating under pressure after a step of die-bonding a semiconductor chip on an adherend.

The third aspect of the present invention also relates to a semiconductor device.

According to the first and second aspects of the present invention, it is possible to provide a film adhesive excellent in conductivity and a dicing tape with a film adhesive.

It is a cross-sectional schematic diagram of a dicing tape with a film adhesive. It is a cross-sectional schematic diagram of the dicing tape with a film adhesive which concerns on a modification. It is process sectional drawing for demonstrating an example of the manufacturing method of a semiconductor device. It is a schematic sectional drawing of a film adhesive. It is a schematic sectional drawing of a dicing tape with a film adhesive. It is a schematic sectional drawing of the dicing tape with a film adhesive which concerns on a modification. It is sectional drawing which shows the outline of a mode that the semiconductor wafer has been arrange | positioned on the dicing tape with a film adhesive. It is sectional drawing which shows the outline of a mode that the semiconductor wafer was separated into pieces. It is a schematic sectional drawing of a to-be-adhered body with a semiconductor chip. It is a schematic sectional drawing of a semiconductor device.

[First Invention]
The film adhesive of 1st this invention contains electroconductive particle. Examples of the conductive particles include gold particles, silver particles, copper particles, and coated particles.

The coated particle includes a core particle and a coating film that coats the core particle. The core particles may be either conductive or non-conductive, and for example, glass particles can be used. Examples of the coating film include a film containing gold, a film containing silver, and a film containing copper.

The conductive particles include plate-like particles having an aspect ratio of 5 or more. Since it is 5 or more, the plate-like particles are easily brought into surface contact with each other, and a conductive path is easily formed. The aspect ratio is preferably 8 or more, more preferably 10 or more. On the other hand, the aspect ratio is preferably 10,000 or less, more preferably 100 or less, still more preferably 70 or less, and particularly preferably 50 or less.

The aspect ratio of the plate-like particles is the ratio of the average major axis to the average thickness (average major axis / average thickness).
In this specification, the average major axis of the plate-like particles can be obtained by observing the cross section of the film-like adhesive with a scanning electron microscope (SEM) and measuring the major axis of 100 randomly selected plate-like particles. Average value.
The average thickness of the plate-like particles is an average value obtained by observing the cross section of the film-like adhesive with a scanning electron microscope (SEM) and measuring the thickness of 100 randomly selected plate-like particles. is there.

The average major axis of the plate-like particles is preferably 0.5 μm or more, more preferably 1.0 μm or more. When the thickness is 0.5 μm or more, the contact probability of the plate-like particles is increased, and conduction is easily obtained.
On the other hand, the average major axis of the plate-like particles is preferably 50 μm or less, more preferably 30 μm or less. When the thickness is 50 μm or less, particles are hardly precipitated at the coating varnish stage, and a stable coating varnish can be produced.

The conductive particles may include needle-like particles, filament-like particles, spherical particles and the like in addition to the plate-like particles. Among these, spherical particles are preferable because high conductivity can be obtained.

The content of plate-like particles in 100% by weight of the conductive particles is preferably 5% by weight or more, more preferably 10% by weight or more. The content of the plate-like particles in 100% by weight of the conductive particles may be 100% by weight, but is preferably 50% by weight or less, more preferably 20% by weight or less.

The content of spherical particles in 100% by weight of the conductive particles is preferably 50% by weight or more, more preferably 80% by weight or more. The content of spherical particles in 100% by weight of the conductive particles is preferably 95% by weight or less, more preferably 90% by weight or less.

The average particle diameter of the conductive particles is not particularly limited, but 0.001 times or more (thickness of film adhesive × 0.001 or more) is preferable and 0.1 times or more with respect to the thickness of the film adhesive. More preferred. If it is less than 0.001, it is difficult to form a conductive path and the conductivity tends to be unstable. Further, the average particle diameter of the conductive particles is preferably 1 times or less (less than the thickness of the film adhesive), more preferably 0.8 times or less with respect to the thickness of the film adhesive. If it exceeds 1 time, there is a risk of cracking the chip.
The average particle diameter of the conductive particles is a value obtained by a photometric particle size distribution meter (manufactured by HORIBA, apparatus name: LA-910).

The specific gravity of the conductive particles is preferably 0.7 or more, and more preferably 1 or more. If it is less than 0.7, the conductive particles float when the adhesive composition solution (varnish) is produced, and the dispersion of the conductive particles may be uneven. The specific gravity of the conductive particles is preferably 22 or less, and more preferably 21 or less. If it exceeds 22, the conductive particles are likely to sink, and the dispersion of the conductive particles may be uneven.

The content of the conductive particles in the film adhesive is preferably 30% by weight or more, more preferably 40% by weight or more. If it is less than 30% by weight, it tends to be difficult to form a conductive path. Further, the content of the conductive particles is preferably 95% by weight or less, more preferably 94% by weight or less. If it exceeds 95% by weight, film formation tends to be difficult. In addition, the adhesion to the wafer tends to decrease.

The film adhesive preferably contains a thermoplastic resin. Thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplasticity. Examples thereof include polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluorine resins. Of these thermoplastic resins, an acrylic resin that has few ionic impurities and high heat resistance and can ensure the reliability of the semiconductor element is particularly preferable.

The acrylic resin is not particularly limited, and one or more of acrylic acid or methacrylic acid ester having a linear or branched alkyl group having 30 or less carbon atoms, particularly 4 to 18 carbon atoms, is used as a component. And a polymer (acrylic copolymer). Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2- Examples include ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group, and dodecyl group.

In addition, the other monomer forming the polymer (acrylic copolymer) is not particularly limited, and for example, acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid Or a carboxyl group-containing monomer such as crotonic acid, an acid anhydride monomer such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth ) 4-hydroxybutyl acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4 -Hydroxymethylcyclo Hydroxyl group-containing monomers such as (xyl) -methyl acrylate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate Alternatively, a sulfonic acid group-containing monomer such as (meth) acryloyloxynaphthalene sulfonic acid, or a phosphoric acid group-containing monomer such as 2-hydroxyethylacryloyl phosphate can be used.

Among the acrylic resins, those having a weight average molecular weight of 100,000 or more are preferable, those having 300,000 to 3,000,000 are more preferable, and those having 500,000 to 2,000,000 are more preferable. It is because it is excellent in adhesiveness and heat resistance in the said numerical range. The weight average molecular weight is a value measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

The glass transition temperature of the thermoplastic resin is preferably −40 ° C. or higher, more preferably −35 ° C. or higher, and further preferably −25 ° C. or higher. When the temperature is lower than −40 ° C., the film-like adhesive becomes sticky and tends to stick to the dicing tape, resulting in poor pick-up properties. The glass transition temperature of the thermoplastic resin is preferably −10 ° C. or lower, more preferably −11 ° C. or lower. When it exceeds −10 ° C., the elastic modulus increases, and it tends to be difficult to attach the film adhesive to the semiconductor wafer at a low temperature of about 40 ° C. (low temperature sticking property is lowered).
In this specification, the glass transition temperature of a thermoplastic resin means the theoretical value calculated | required by the Fox formula.
As another method for obtaining the glass transition temperature, there is a method for obtaining the glass transition temperature of the thermoplastic resin from the temperature at the maximum heat absorption peak measured by a differential scanning calorimeter (DSC). Specifically, a differential scanning calorimeter (“Q-2000” manufactured by TA Instruments Inc.) is used as a sample to be measured, and is about 50 ° C. higher than the predicted glass transition temperature (predicted temperature) of the sample. After heating at a temperature for 10 minutes, the sample is cooled to a temperature lower by 50 ° C. than the predicted temperature, pre-treated, and then heated at a rate of temperature increase of 5 ° C./min in a nitrogen atmosphere to measure the endothermic start point temperature, This is the glass transition temperature.

The film adhesive preferably contains a curable resin such as a thermosetting resin. Thereby, thermal stability can be improved.

Examples of the curable resin include phenol resin, amino resin, unsaturated polyester resin, epoxy resin, polyurethane resin, silicone resin, and thermosetting polyimide resin. In particular, an epoxy resin containing a small amount of ionic impurities that corrode semiconductor elements is preferable. Moreover, as a hardening | curing agent of an epoxy resin, a phenol resin is preferable.

The epoxy resin is not particularly limited. For example, bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type. Bifunctional epoxy resins such as ortho-cresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., and epoxy resins such as hydantoin type, trisglycidyl isocyanurate type, or glycidylamine type are used. Of these epoxy resins, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type resins or tetraphenylolethane type epoxy resins are particularly preferred. This is because these epoxy resins are rich in reactivity with a phenol resin as a curing agent and are excellent in heat resistance.

The phenol resin acts as a curing agent for the epoxy resin. For example, a novolac type phenol resin such as a phenol novolak resin, a phenol aralkyl resin, a cresol novolak resin, a tert-butylphenol novolak resin, a nonylphenol novolak resin, or a resol type phenol resin. And polyoxystyrene such as polyparaoxystyrene. Of these phenol resins, phenol novolac resins and phenol aralkyl resins are particularly preferred. This is because the connection reliability of the semiconductor device can be improved.

The blending ratio of the epoxy resin and the phenol resin is preferably such that, for example, the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per equivalent of epoxy group in the epoxy resin component. More preferred is 0.8 to 1.2 equivalents. That is, if the blending ratio of both is out of the above range, sufficient curing reaction does not proceed and the properties of the cured product are likely to deteriorate.

The film adhesive preferably contains a curable resin that is solid at 25 ° C. and a curable resin that is liquid at 25 ° C. Thereby, favorable low-temperature sticking property is obtained.
In this specification, the liquid state at 25 ° C. means that the viscosity at 25 ° C. is less than 5000 Pa · s. On the other hand, solid at 25 ° C. means that the viscosity at 25 ° C. is 5000 Pa · s or more.
The viscosity can be measured using a model number HAAKE Roto VISCO1 manufactured by Thermo Scientific.

In the film adhesive, the content of the curable resin solid at 25 ° C. in 100% by weight of the curable resin is preferably 10% by weight or more, more preferably 12% by weight or more. If it is less than 10% by weight, the film-like adhesive becomes sticky, and it tends to stick to the dicing tape, resulting in poor pick-up properties.
On the other hand, the content of the curable resin solid at 25 ° C. in 100% by weight of the curable resin is preferably 60% by weight or less, more preferably 30% by weight or less, and further preferably 20% by weight or less. If it exceeds 60% by weight, it tends to be difficult to attach the film adhesive to the semiconductor wafer at a low temperature of about 40 ° C. (low temperature sticking property is lowered).

The total content of the thermoplastic resin and the curable resin in the film adhesive is preferably 5% by weight or more, more preferably 10% by weight or more. When it is 5% by weight or more, it is easy to maintain the shape as a film. Further, the total content of the thermoplastic resin and the curable resin is preferably 70% by weight or less, more preferably 60% by weight or less. When the content is 70% by weight or less, the conductive particles suitably exhibit conductivity.

In the film adhesive, the weight of the thermoplastic resin / weight of the curable resin is preferably 50/50 to 10/90, and more preferably 40/60 to 15/85. When the ratio of the thermoplastic resin increases from 50/50, the thermal stability tends to deteriorate. On the other hand, when the ratio of the thermoplastic resin is less than 10/90, it tends to be difficult to form a film.

In addition to the above components, the film adhesive may appropriately contain a compounding agent generally used in film production, such as a crosslinking agent.

A film adhesive can be manufactured by a normal method. For example, an adhesive composition solution containing each of the above components is prepared, and the adhesive composition solution is applied on a base separator so as to have a predetermined thickness to form a coating film, and then the coating film is dried. Thus, a film adhesive can be produced.

Although it does not specifically limit as a solvent used for adhesive composition solution, The organic solvent which can melt | dissolve, knead | mix or disperse | distribute each said component uniformly is preferable. Examples thereof include ketone solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, acetone, methyl ethyl ketone, and cyclohexanone, toluene, xylene, and the like. The application method is not particularly limited. Examples of the solvent coating method include a die coater, a gravure coater, a roll coater, a reverse coater, a comma coater, a pipe doctor coater, and screen printing. Of these, a die coater is preferable in terms of high uniformity of coating thickness.

As the base material separator, polyethylene terephthalate (PET), polyethylene, polypropylene, a plastic film or paper whose surface is coated with a release agent such as a fluorine-type release agent or a long-chain alkyl acrylate release agent can be used. Examples of the method for applying the adhesive composition solution include roll coating, screen coating, and gravure coating. The drying conditions for the coating film are not particularly limited, and for example, the drying can be performed at a drying temperature of 70 to 160 ° C. and a drying time of 1 to 5 minutes.

As a method for producing a film-like adhesive, for example, a method of producing the film-like adhesive by mixing the respective components with a mixer and press-molding the obtained mixture is also suitable. A planetary mixer etc. are mentioned as a mixer.

Although the thickness of a film adhesive is not specifically limited, 5 micrometers or more are preferable and 15 micrometers or more are more preferable. When the thickness is less than 5 μm, a portion where the warped semiconductor wafer or the semiconductor chip does not adhere may occur, and the adhesion area may become unstable. The thickness of the film adhesive is preferably 100 μm or less, more preferably 50 μm or less. If it exceeds 100 μm, the film adhesive may excessively protrude due to the load of die attachment, and the pad may be contaminated.

The film-like adhesive has an adhesive force measured at 25 ° C. after being attached to a mirror silicon wafer at 40 ° C., preferably 0.5 N / 10 mm or more, more preferably 0.6 N / 10 mm or more, and further preferably 4 N. / 10 mm or more. When the thickness is 0.5 N / 10 mm or more, the film adhesive can be satisfactorily adhered to the semiconductor wafer at a low temperature of about 40 ° C., so that the thermal influence on the semiconductor wafer can be prevented and the warpage of the semiconductor wafer can be suppressed. On the other hand, if it is less than 0.5 N / 10 mm, the adhesion is low and the semiconductor wafer may be peeled off from the film adhesive. The upper limit of the adhesion is not particularly limited, but is, for example, 10 N / 10 mm or less.
In this specification, adhesion means the peeling force when peeling a film adhesive from a mirror silicon wafer, and can be measured by the following method.

Measurement of Peeling Force Using a 2 kg roller, a mirror silicon wafer at 40 ° C. is attached to the film adhesive and then left at 40 ° C. for 2 minutes. Then, it is left to stand at normal temperature (25 ° C.) for 20 minutes to obtain a sample having a film adhesive and a mirror silicon wafer attached to the film adhesive. Using a tensile tester (AGS-J, manufactured by Shimadzu Corporation), the film adhesive was peeled from the mirror silicon wafer with a peeling angle of 180 degrees, a peeling temperature of 25 ° C., and a peeling speed of 300 mm / min. Measure the peel force when

The storage elastic modulus of the film adhesive at 25 ° C. is preferably 5 MPa or more, and more preferably 2 × 10 ² MPa or more. When the pressure is less than 5 MPa, the adhesion with the dicing tape is increased, and the pickup property tends to be reduced. Storage modulus at 25 ° C. of film adhesive is preferably 5 × ¹⁰ 3 MPa or less, more preferably 3 × ¹⁰ 3 MPa or less, more preferably 2.5 × ¹⁰ 3 MPa or less. Exceeding 5 × 10 ³ MPa is difficult in terms of formulation.

The storage elastic modulus at 100 ° C. of the film adhesive is preferably 0.01 MPa or more, and more preferably 0.05 MPa or more. When the pressure is 0.01 MPa or more, it is difficult for the film adhesive to protrude during die attachment. On the other hand, the storage elastic modulus at 100 ° C. of the film adhesive is preferably 1 MPa or less, and more preferably 0.8 MPa or less. When the pressure is 1 MPa or less, it becomes difficult to bite voids at the time of die attachment, and a stable die attachment is likely to occur.

The surface roughness (Ra) of the film adhesive is preferably 0.1 to 5000 nm. If it is less than 0.1 nm, it is difficult to blend. On the other hand, when it exceeds 5000 nm, there exists a possibility that low temperature sticking property may fall. Moreover, the sticking property to the adherend at the time of die attachment may be reduced.

The volume resistivity of the film adhesive is preferably as low as possible, for example, 9 × 10 ⁻² Ω · m or less. When it is 9 × 10 ⁻² Ω · m or less, the electroconductivity is good and it is possible to cope with small size and high density mounting. The volume resistivity is preferably 1 × 10 ⁻² Ω · m or less. On the other hand, the volume resistivity is preferably 1 × 10 ⁻⁶ Ω · m or more.
In addition, volume resistivity can be measured by the method as described in an Example.

The higher the thermal conductivity of the film adhesive, the better. For example, it is 0.5 W / m · K or more. When it is 0.5 W / m · K or more, the heat dissipation is good, and it is possible to cope with small and high-density mounting. On the other hand, if it is less than 0.5 W / m · K, heat dissipation is poor, heat is accumulated, and the conductivity may be deteriorated.

A film adhesive can be used suitably for manufacture of a semiconductor device. Especially, it can use especially suitably as a die attach film which adhere | attaches adherends, such as a lead frame, and a semiconductor chip (die attach). Examples of the adherend include a lead frame, an interposer, and a semiconductor chip. Of these, a lead frame is preferable.

The film adhesive is preferably used in the form of a dicing tape with a film adhesive. When used in this form, the semiconductor wafer in a state of being attached to the dicing tape with a film adhesive can be handled, so that the opportunity to handle the semiconductor wafer alone can be reduced and the handling property is good. Therefore, even a recent thin semiconductor wafer can be handled well. Moreover, when using with this form, although a semiconductor wafer will be affixed on a film adhesive, since the above-mentioned film adhesive is used, the curvature of a semiconductor wafer can be suppressed.

The dicing tape with a film adhesive will be described.

As shown in FIG. 1, a dicing tape 10 with a film adhesive includes a dicing tape 11 and a film adhesive 3 laminated on the dicing tape 11. The dicing tape 11 includes a base material 1 and an adhesive layer 2 laminated on the base material 1. The film adhesive 3 is disposed on the pressure-sensitive adhesive layer 2.

As shown in FIG. 2, the dicing tape 10 with a film adhesive may have a configuration in which the adhesive layer 3 is formed only on a work (semiconductor wafer 4 or the like) attachment portion.

The base material 1 is a strength base of the dicing tape 10 with a film adhesive, and preferably has ultraviolet transparency. Examples of the substrate 1 include low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolyprolene, polybutene, polymethylpentene, and the like. Polyolefin, ethylene-vinyl acetate copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene -Hexene copolymers, polyesters such as polyurethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide Polyphenyl sulphates id, aramid (paper), glass, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, metal (foil), and paper.

The surface of the substrate 1 is chemically treated by conventional surface treatments such as chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. in order to enhance adhesion and retention with adjacent layers. Alternatively, a physical treatment or a coating treatment with a primer (for example, an adhesive substance described later) can be performed.

The thickness of the substrate 1 is not particularly limited and can be appropriately determined, but is generally about 5 to 200 μm.

It does not restrict | limit especially as an adhesive used for formation of the adhesive layer 2, For example, common pressure sensitive adhesives, such as an acrylic adhesive and a rubber adhesive, can be used. As pressure-sensitive adhesives, acrylic adhesives based on acrylic polymers are used as the base polymer from the standpoint of cleanability of electronic components that are difficult to contaminate such as semiconductor wafers and glass with organic solvents such as ultrapure water and alcohol. preferable.

Examples of the acrylic polymer include (meth) acrylic acid alkyl esters (for example, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Pentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, hexadecyl ester, Straight-chain or branched alkyl esters having 1 to 30 carbon atoms, particularly 4 to 18 carbon atoms, such as octadecyl esters and eicosyl esters), and Meth) acrylic acid cycloalkyl esters (e.g., cyclopentyl ester, etc. One or acrylic polymer using two or more of the monomer component cyclohexyl ester etc.). In addition, (meth) acrylic acid ester means acrylic acid ester and / or methacrylic acid ester, and (meth) of the present invention has the same meaning.

The acrylic polymer contains units corresponding to other monomer components copolymerizable with the (meth) acrylic acid alkyl ester or cycloalkyl ester, if necessary, for the purpose of modifying cohesive force, heat resistance and the like. May be. Examples of such monomer components include, for example, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride Acid anhydride monomers such as itaconic anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate Hydroxyl group-containing monomers such as 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; Sti Contains sulfonic acid groups such as ethylene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalene sulfonic acid Monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate; acrylamide, acrylonitrile and the like. One or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 40% by weight or less based on the total monomer components.

Furthermore, since the acrylic polymer is cross-linked, a polyfunctional monomer or the like can be included as a monomer component for copolymerization as necessary. Examples of such polyfunctional monomers include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) An acrylate etc. are mentioned. These polyfunctional monomers can also be used alone or in combination of two or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

The acrylic polymer can be obtained by subjecting a single monomer or a mixture of two or more monomers to polymerization. The polymerization can be carried out by any method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization and the like. From the viewpoint of preventing contamination of a clean adherend, it is preferable that the content of the low molecular weight substance is small. From this point, the number average molecular weight of the acrylic polymer is preferably 300,000 or more, more preferably about 400,000 to 3 million.

In addition, an external cross-linking agent can be appropriately employed for the pressure-sensitive adhesive in order to increase the number average molecular weight of an acrylic polymer as a base polymer. Specific examples of the external crosslinking method include a method of adding a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, or a melamine crosslinking agent and reacting them. When using an external cross-linking agent, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked and further depending on the intended use as an adhesive. Generally, it is preferable to add about 5 parts by weight or less, more preferably 0.1 to 5 parts by weight, with respect to 100 parts by weight of the base polymer. Furthermore, additives such as various conventionally known tackifiers and anti-aging agents may be used for the pressure-sensitive adhesive, if necessary, in addition to the above components.

The pressure-sensitive adhesive layer 2 can be formed of a radiation curable pressure-sensitive adhesive. The radiation curable pressure-sensitive adhesive can easily reduce its adhesive strength by increasing the degree of crosslinking by irradiation with radiation such as ultraviolet rays.

By irradiating only the part 2a corresponding to the work pasting part of the pressure-sensitive adhesive layer 2 shown in FIG. 1, a difference in adhesive force with the other part 2b can be provided. In this case, the said part 2b currently formed with the uncured radiation-curing-type adhesive can adhere to the film adhesive 3, and can ensure the retention strength at the time of dicing.

Moreover, the said part 2a in which adhesive force fell remarkably can be formed by hardening the radiation-curing-type adhesive layer 2 according to the film adhesive 3 shown in FIG. In this case, the wafer ring can be fixed to the portion 2b formed of the uncured radiation curable adhesive.

That is, when the pressure-sensitive adhesive layer 2 is formed of a radiation curable pressure-sensitive adhesive, the portion 2a is irradiated with radiation so that the pressure-sensitive adhesive force of the portion 2a in the pressure-sensitive adhesive layer 2 <the pressure-sensitive adhesive strength of the other portion 2b. It is preferable.

As the radiation curable pressure-sensitive adhesive, those having a radiation curable functional group such as a carbon-carbon double bond and exhibiting adhesiveness can be used without particular limitation. Examples of the radiation curable pressure-sensitive adhesive include an addition-type radiation curable pressure-sensitive adhesive in which a radiation-curable monomer component or oligomer component is blended with a general pressure-sensitive pressure-sensitive adhesive such as the acrylic pressure-sensitive adhesive or rubber-based pressure-sensitive adhesive. An agent can be illustrated.

Examples of the radiation curable monomer component to be blended include urethane oligomer, urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol. Stall tetra (meth) acrylate, dipentaerystol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, and the like. Examples of the radiation curable oligomer component include urethane, polyether, polyester, polycarbonate, and polybutadiene oligomers, and those having a molecular weight in the range of about 100 to 30000 are suitable. The compounding amount of the radiation-curable monomer component or oligomer component can be appropriately determined in accordance with the type of the pressure-sensitive adhesive layer, and the amount capable of reducing the adhesive strength of the pressure-sensitive adhesive layer. In general, the amount is, for example, about 5 to 500 parts by weight, preferably about 40 to 150 parts by weight with respect to 100 parts by weight of a base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

In addition to the additive-type radiation-curable pressure-sensitive adhesive described above, the radiation-curable pressure-sensitive adhesive has a carbon-carbon double bond in the polymer side chain, main chain, or main chain terminal as a base polymer. Intrinsic radiation curable pressure sensitive adhesives using Intrinsic radiation curable adhesives do not need to contain oligomer components, which are low molecular components, or do not contain many, so the oligomer components do not move through the adhesive over time and are stable. It is preferable because an adhesive layer having a layered structure can be formed.

As the base polymer having a carbon-carbon double bond, those having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. As such a base polymer, those having an acrylic polymer as a basic skeleton are preferable. Examples of the basic skeleton of the acrylic polymer include the acrylic polymers exemplified above.

The method for introducing the carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be adopted. However, the carbon-carbon double bond can be easily introduced into the polymer side chain for easy molecular design. . For example, after a monomer having a functional group is copolymerized in advance with an acrylic polymer, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is converted into a radiation-curable carbon-carbon double bond. A method of performing condensation or addition reaction while maintaining the above.

Examples of combinations of these functional groups include carboxylic acid groups and epoxy groups, carboxylic acid groups and aziridyl groups, hydroxyl groups and isocyanate groups. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable because of easy tracking of the reaction. In addition, the functional group may be on either side of the acrylic polymer and the compound as long as the combination of these functional groups generates an acrylic polymer having the carbon-carbon double bond. In the preferable combination, it is preferable that the acrylic polymer has a hydroxyl group and the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate, and the like. As the acrylic polymer, those obtained by copolymerizing the above-mentioned exemplified hydroxy group-containing monomers, ether compounds of 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, or the like are used.

As the intrinsic radiation curable pressure-sensitive adhesive, the base polymer (particularly acrylic polymer) having the carbon-carbon double bond can be used alone, but the radiation curable monomer does not deteriorate the characteristics. Components and oligomer components can also be blended. The radiation-curable oligomer component is usually in the range of 30 parts by weight, preferably in the range of 0 to 10 parts by weight, based on 100 parts by weight of the base polymer.

The radiation curable pressure-sensitive adhesive contains a photopolymerization initiator when cured by ultraviolet rays or the like. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-dimethylacetophenone, 2-methyl-2-hydroxypropio Α-ketol compounds such as phenone and 1-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1- [4- ( Acetophenone compounds such as methylthio) -phenyl] -2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; 2-naphthalenesulfo Aromatic sulfonyl chloride compounds such as luchloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime; benzophenone, benzoylbenzoic acid, 3,3′-dimethyl Benzophenone compounds such as -4-methoxybenzophenone; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2 Thioxanthone compounds such as 1,4-diethylthioxanthone and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketone; acyl phosphinoxide; acyl phosphonate. The blending amount of the photopolymerization initiator is, for example, about 0.05 to 20 parts by weight with respect to 100 parts by weight of the base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

Examples of the radiation curable pressure-sensitive adhesive include photopolymerizable compounds such as an addition polymerizable compound having two or more unsaturated bonds and an alkoxysilane having an epoxy group disclosed in JP-A-60-196956. And rubber-based pressure-sensitive adhesives and acrylic pressure-sensitive adhesives containing photopolymerization initiators such as carbonyl compounds, organic sulfur compounds, peroxides, amines, and onium salt-based compounds.

The radiation curable pressure-sensitive adhesive layer 2 can contain a compound that is colored by irradiation with radiation, if necessary. By including a compound to be colored in the pressure-sensitive adhesive layer 2 by irradiation with radiation, only the irradiated portion can be colored. The compound that is colored by irradiation with radiation is a colorless or light color compound before irradiation with radiation, but becomes a color by irradiation with radiation, and examples thereof include leuco dyes. The use ratio of the compound colored by radiation irradiation can be set as appropriate.

The thickness of the pressure-sensitive adhesive layer 2 is not particularly limited, but it is preferably about 1 to 50 μm from the viewpoint of preventing chipping of the chip cut surface and compatibility of fixing and holding the adhesive layer. The thickness is preferably 2 to 30 μm, more preferably 5 to 25 μm.

The film adhesive 3 of the dicing tape 10 with a film adhesive is preferably protected by a separator (not shown). The separator has a function as a protective material for protecting the film adhesive 3 until it is put into practical use. The separator is peeled off when the workpiece is stuck on the film adhesive 3. As the separator, it is also possible to use polyethylene terephthalate (PET), polyethylene, polypropylene, a plastic film or paper whose surface is coated with a release agent such as a fluorine release agent or a long-chain alkyl acrylate release agent.

The dicing tape 10 with a film adhesive can be manufactured by a normal method. For example, the dicing tape 10 with a film adhesive can be manufactured by bonding the pressure-sensitive adhesive layer 2 of the dicing tape 11 and the film adhesive 3 together.

The peeling force when the film adhesive 3 is peeled off from the dicing tape 11 under the conditions of a peeling temperature of 25 ° C. and a peeling speed of 300 mm / min is preferably 0.01 to 3.00 N / 20 mm. If it is less than 0.01 N / 20 mm, there is a risk of chip jumping during dicing. On the other hand, if it exceeds 3.00 N / 20 mm, the pickup tends to be difficult.
The peeling force when the film adhesive 3 is peeled from the dicing tape 11 under the conditions of a peeling temperature of 25 ° C. and a peeling speed of 300 mm / min can be measured by the method described in the examples.

An example of a method for manufacturing a semiconductor device using the dicing tape with a film adhesive 10 will be described with reference to FIG.

First, the semiconductor wafer 4 is pressure-bonded onto the semiconductor wafer attaching portion 3a of the film adhesive 3 in the dicing tape 10 with a film adhesive, and this is bonded and held (fixing step). This step is performed while pressing with a pressing means such as a pressure roll. At this time, it can be crimped at a low temperature of about 40 ° C. Specifically, the pressure bonding temperature (sticking temperature) is preferably 35 ° C. or higher, and more preferably 37 ° C. or higher. The upper limit of the pressure bonding temperature is preferably lower, preferably 50 ° C. or lower, more preferably 45 ° C. or lower, and further preferably 43 ° C. or lower. Since it can be attached to the semiconductor wafer 4 at a low temperature of about 40 ° C., the thermal effect on the semiconductor wafer 4 can be prevented and the warpage of the semiconductor wafer 4 can be suppressed.

The pressure is preferably 1 × 10 ⁵ to 1 × 10 ⁷ Pa, and more preferably 2 × 10 ⁵ to 8 × 10 ⁶ Pa. The sticking time is preferably 1 second to 5 minutes, more preferably 1 minute to 3 minutes.

Next, dicing of the semiconductor wafer 4 is performed. Thereby, the semiconductor wafer 4 is cut into a predetermined size and separated into individual pieces, and the semiconductor chip 5 is manufactured. Dicing is performed according to a conventional method, for example, from the circuit surface side of the semiconductor wafer 4. Further, in this step, for example, a cutting method called full cut in which cutting is performed up to the dicing tape 10 with a film adhesive can be employed. It does not specifically limit as a dicing apparatus used at this process, A conventionally well-known thing can be used. Moreover, since the semiconductor wafer 4 is bonded and fixed by the dicing tape 10 with a film adhesive, chip chipping and chip jump can be suppressed, and damage to the semiconductor wafer 4 can also be suppressed.

The semiconductor chip 5 is picked up in order to peel off the semiconductor chip 5 bonded and fixed to the dicing tape with film adhesive 10. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, there is a method in which each semiconductor chip 5 is pushed up by a needle from the dicing tape 10 with film adhesive, and the pushed-up semiconductor chip 5 is picked up by a pickup device.

Here, when the pressure-sensitive adhesive layer 2 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 2 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the film adhesive 3 of the adhesive layer 2 falls, and peeling of the semiconductor chip 5 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip 5. Conditions such as irradiation intensity and irradiation time at the time of ultraviolet irradiation are not particularly limited, and may be set as necessary.

The picked-up semiconductor chip 5 is bonded and fixed to the adherend 6 via the film adhesive 3 (die attach).

The die attach temperature is preferably 80 ° C. or higher, more preferably 90 ° C. or higher. The die attach temperature is preferably 150 ° C. or lower, more preferably 130 ° C. or lower. By setting the temperature to 150 ° C. or lower, it is possible to prevent warping after die attachment.

Subsequently, the film adhesive 3 is thermally cured by heating, and the semiconductor chip 5 and the adherend 6 are bonded. Preferably, the film adhesive 3 is thermally cured by heating in a pressurized atmosphere, and the semiconductor chip 5 and the adherend 6 are bonded. By thermally curing the film adhesive 3 in a pressurized atmosphere, voids existing between the film adhesive 3 and the adherend 6 can be eliminated, and the film adhesive 3 is adhered. An area in contact with the body 6 can be secured.

The pressure of the pressurized atmosphere is preferably 0.5 kg / cm ² (4.9 × 10 ⁻² MPa) or more, more preferably 1 kg / cm ² (9.8 × 10 ⁻² MPa) or more, and further preferably 5 kg. / Cm ² (4.9 × 10 ⁻¹ MPa) or more. If it is 0.5 kg / cm ² or more, voids existing between the film adhesive 3 and the adherend 6 can be easily eliminated. The pressure of the pressurized atmosphere is preferably 20kg ^/ cm 2 (1.96MPa), more preferably 18kg ^/ cm 2 (1.77MPa) or less, more preferably not more than 15kg ^/ cm 2 (1.47MPa). The protrusion of the film adhesive 3 due to excessive pressurization can be suppressed as it is 20 kg / cm ² or less.

The temperature of the heat treatment is preferably 80 ° C. or higher, more preferably 170 ° C. or higher. The temperature of the heat treatment is preferably 200 ° C. or lower, more preferably 180 ° C. or lower. Adhesion can be satisfactorily performed when the temperature of the heat treatment is within the above range. Moreover, the time of heat processing can be set suitably.

Next, a wire bonding step of electrically connecting the tip of the terminal portion (inner lead) of the adherend 6 and an electrode pad (not shown) on the semiconductor chip 5 with the bonding wire 7 is performed. As the bonding wire 7, for example, a gold wire, an aluminum wire or a copper wire is used. The temperature during wire bonding is preferably 80 ° C. or higher, more preferably 120 ° C. or higher, and the temperature is preferably 250 ° C. or lower, more preferably 175 ° C. or lower. The heating time is several seconds to several minutes (for example, 1 second to 1 minute). The connection is performed by a combination of vibration energy by ultrasonic waves and pressure energy by pressurization while being heated so as to be within the temperature range.

Subsequently, a sealing step for sealing the semiconductor chip 5 with the sealing resin 8 is performed. This step is performed to protect the semiconductor chip 5 and the bonding wire 7 mounted on the adherend 6. This step is performed by molding a sealing resin with a mold. As the sealing resin 8, for example, an epoxy resin is used. The heating temperature at the time of resin sealing is preferably 165 ° C. or higher, more preferably 170 ° C. or higher, and the heating temperature is preferably 185 ° C. or lower, more preferably 180 ° C. or lower.

If necessary, the sealed material may be further heated (post-curing step). Thereby, the sealing resin 8 which is insufficiently cured in the sealing process can be completely cured. The heating temperature can be set as appropriate.

As described above, a semiconductor device can be manufactured by a method including the step of die-attaching the semiconductor chip 5 to the adherend 6 using the film adhesive 3. That is, a semiconductor device can be manufactured by a method including a step of pressure-bonding a die bonding chip including the film adhesive 3 and the semiconductor chip 5 in contact with the film adhesive 3 to the adherend 6.

For example, the process I arrange | positions the semiconductor wafer 4 on the film adhesive 3 of the dicing tape 10 with a film adhesive, and the semiconductor wafer 4 arrange | positioned on the film adhesive 3 is diced, and the semiconductor chip 5 is formed. Step II, Step III of picking up the semiconductor chip 5 formed in Step II together with the film adhesive 3, and die attachment of the semiconductor chip 5 picked up in Step III to the adherend 6 through the film adhesive 3 A semiconductor device can be suitably manufactured by the method including the step IV.

The first invention has been described above.

[Second Invention]
The second invention is the same as the first invention except for the conductive particles. Therefore, only the conductive particles will be described below.

The film adhesive of 2nd this invention contains electroconductive particle. Examples of the conductive particles include gold particles, silver particles, copper particles, and coated particles.

The conductive particles include spherical spherical particles.

At least the peak A and the peak B exist in the particle size distribution of the spherical particles. Specifically, the peak A exists in the particle size range of 0.2 μm to 0.8 μm, and the peak B exists in the particle size range of 3 μm to 15 μm. In the film adhesive, the spherical particles forming the peak A are filled between the spherical particles forming the peak B, so that many contact points between the spherical particles are formed. Therefore, excellent conductivity can be obtained.

Since the peak A exists in a particle size range of 0.2 μm or more, aggregation of spherical particles hardly occurs.
The peak A is preferably present in a particle size range of 0.5 μm or more.
Since the peak A exists in a particle size range of 0.8 μm or less, the spherical particles forming the peak A are filled between the spherical particles forming the peak B. The peak A is preferably present in a particle size range of 0.75 μm or less.

Since the peak B exists in the particle size range of 3 μm or more, the spherical particles forming the peak A are filled between the spherical particles forming the peak B. The peak B is preferably present in a particle size range of 3.5 μm or more.
Since the peak B exists in a particle size range of 15 μm or less, the surface roughness when the film is formed can be suppressed and can be stably adhered to the adherend. The peak B is preferably present in a particle size range of 10 μm or less, more preferably in a particle size range of 8 μm or less, and further preferably in a particle size range of 6 μm or less.

The ratio of the peak B particle size to the peak A particle size (peak B particle size / peak A particle size) is 5 or more, preferably 7 or more. Since it is 5 or more, the spherical particles forming the peak A are filled between the spherical particles forming the peak B.
On the other hand, the ratio of the particle size of peak B to the particle size of peak A is 15 or less, preferably 10 or less. Since it is 15 or less, spherical particles can be highly filled.

In the particle size distribution of the spherical particles, peaks other than peak A and peak B may exist.

The particle size distribution of the spherical particles can be measured by the method described in the examples.

The average particle diameter of the spherical particles is preferably 1 μm or more, more preferably 1.5 μm or more. When the thickness is 1 μm or more, good unevenness followability can be obtained. The average particle diameter of the spherical particles is preferably 10 μm or less, more preferably 8 μm or less, and further preferably 5 μm or less. Film moldability is favorable in it being 10 micrometers or less.
The average particle size of the spherical particles can be measured by the method described in the examples.

The conductive particles may include needle-like particles, filament-like particles, plate-like particles and the like in addition to the spherical particles.

The content of spherical particles in 100% by weight of the conductive particles is preferably 5% by weight or more, more preferably 80% by weight or more, still more preferably 90% by weight or more, and particularly preferably 100% by weight.

The suitable average particle diameter and suitable specific gravity of electroconductive particle are as having demonstrated with the 1st film adhesive.

Suitable conductive particle content is as described in the first film-like adhesive.

The second invention has been described above.

[Third Invention]
As shown in FIG. 4, the form of the film adhesive 103 is a film form. The film adhesive 103 has conductivity and thermosetting. The description of the film adhesive 103 is the same as the film adhesives of the first and second inventions. Therefore, the film adhesive 103 will be briefly described.

The film adhesive 103 preferably contains a thermoplastic resin. Thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplasticity. Examples thereof include polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluorine resins. Of these thermoplastic resins, an acrylic resin that has few ionic impurities and high heat resistance and can ensure the reliability of the semiconductor element is particularly preferable.

The glass transition temperature of the thermoplastic resin is preferably −40 ° C. or higher, more preferably −35 ° C. or higher, and further preferably −25 ° C. or higher. When the temperature is lower than −40 ° C., the film-like adhesive 103 becomes sticky and sticks to the dicing tape so that the pickup property tends to deteriorate. Further, the glass transition temperature of the thermoplastic resin is preferably −5 ° C. or lower, more preferably −10 ° C. or lower, and further preferably −11 ° C. or lower. When the temperature exceeds −10 ° C., the elastic modulus increases, and it tends to be difficult to attach the film adhesive 103 to the semiconductor wafer at a low temperature of about 40 ° C. (low-temperature sticking property decreases). Further, when the glass transition temperature of the thermoplastic resin is −5 ° C. or lower, the fluidity of the film-like adhesive 103 near the thermosetting temperature can be improved, and voids can be easily eliminated by heating under pressure. It becomes.

The film adhesive 103 preferably contains a curable resin such as a thermosetting resin. Thereby, thermal stability can be improved.

The film adhesive 103 preferably contains a curable resin that is solid at 25 ° C. and a curable resin that is liquid at 25 ° C. Thereby, favorable low-temperature sticking property is obtained.

In the film adhesive 103, the content of the curable resin solid at 25 ° C. in 100% by weight of the curable resin is preferably 10% by weight or more, more preferably 12% by weight or more. If it is less than 10% by weight, the film-like adhesive 103 becomes sticky and sticks to the dicing tape so that the pickup property tends to be poor. On the other hand, the content of the curable resin solid at 25 ° C. in 100% by weight of the curable resin is preferably 60% by weight or less, more preferably 30% by weight or less, and further preferably 20% by weight or less. If it exceeds 60% by weight, it tends to be difficult to attach the film adhesive 103 to the semiconductor wafer at a low temperature of about 40 ° C. (low temperature sticking property is lowered).

The total content of the thermoplastic resin and the curable resin in the film adhesive 103 is preferably 5% by weight or more, more preferably 10% by weight or more. When it is 5% by weight or more, it is easy to maintain the shape as a film. Further, the total content of the thermoplastic resin and the curable resin is preferably 70% by weight or less, more preferably 60% by weight or less. When the content is 70% by weight or less, the conductive particles suitably exhibit conductivity.

In the film adhesive 103, the weight of the thermoplastic resin / the weight of the curable resin is preferably 50/50 to 10/90, and more preferably 40/60 to 15/85. When the ratio of the thermoplastic resin increases from 50/50, the thermal stability tends to deteriorate. On the other hand, when the ratio of the thermoplastic resin is less than 10/90, it tends to be difficult to form a film.

The film adhesive 103 preferably includes conductive particles. Thereby, electroconductivity can be provided. Examples of the conductive particles include gold particles, silver particles, copper particles, and coated particles.

The average particle diameter of the conductive particles is not particularly limited, but is preferably 0.001 times or more (thickness of the film adhesive 103 × 0.001 or more) with respect to the thickness of the film-like adhesive 103, and 0.1 times. The above is more preferable. If it is less than 0.001, it is difficult to form a conductive path and the conductivity tends to be unstable. Further, the average particle diameter of the conductive particles is preferably 1 times or less (less than the thickness of the film adhesive 103), more preferably 0.8 times or less the thickness of the film adhesive 103. If it exceeds 1 time, there is a risk of cracking the chip.
The average particle diameter of the conductive particles is a value obtained by a photometric particle size distribution meter (manufactured by HORIBA, apparatus name: LA-910).

The conductive particles may include plate-like particles, spherical particles, needle-like particles, filament-like particles and the like. Especially, it is preferable that electroconductive particle contains a plate-shaped particle and a spherical particle.

Examples of the plate-like particles include plate-like particles having an aspect ratio of 5 or more. When it is 5 or more, the plate-like particles are easily brought into surface contact with each other, and a conductive path is easily formed.
The aspect ratio is preferably 8 or more, more preferably 10 or more. On the other hand, the aspect ratio is preferably 10,000 or less, more preferably 100 or less, still more preferably 70 or less, and particularly preferably 50 or less.

The aspect ratio of the plate-like particles is the ratio of the average major axis to the average thickness (average major axis / average thickness).

The conductive particles preferably include spherical spherical particles.

It is preferable that at least peak A and peak B exist in the particle size distribution of the spherical particles. For example, it is preferable that the peak A exists in the particle size range of 0.2 μm to 0.8 μm and the peak B exists in the particle size range of 3 μm to 15 μm. In the film adhesive 103, the spherical particles forming the peak A are filled between the spherical particles forming the peak B, so that a large number of contact points between the spherical particles are formed. Therefore, excellent conductivity can be obtained.

When the peak A is present in a particle size range of 0.2 μm or more, aggregation of spherical particles is difficult to occur.
The peak A is preferably present in a particle size range of 0.5 μm or more.
When the peak A exists in a particle size range of 0.8 μm or less, the spherical particles forming the peak A are filled between the spherical particles forming the peak B. The peak A is preferably present in a particle size range of 0.75 μm or less.

When the peak B exists in a particle size range of 3 μm or more, the spherical particles forming the peak A are filled between the spherical particles forming the peak B. The peak B is preferably present in a particle size range of 3.5 μm or more.
When the peak B exists in a particle size range of 15 μm or less, the surface roughness when the film is formed can be suppressed, and can be stably adhered to the adherend. The peak B is preferably present in a particle size range of 10 μm or less, more preferably in a particle size range of 8 μm or less, and further preferably in a particle size range of 6 μm or less.

The ratio of the peak B particle size to the peak A particle size (peak B particle size / peak A particle size) is preferably 5 or more, more preferably 7 or more. When it is 5 or more, spherical particles forming the peak A are filled between the spherical particles forming the peak B.
On the other hand, the ratio of the particle size of peak B to the particle size of peak A is preferably 15 or less, more preferably 10 or less. When it is 15 or less, spherical particles can be highly filled.

The average particle diameter of the spherical particles is preferably 1 μm or more, more preferably 1.5 μm or more. When the thickness is 1 μm or more, good unevenness followability can be obtained. The average particle diameter of the spherical particles is preferably 10 μm or less, more preferably 8 μm or less, and further preferably 5 μm or less. Film moldability is favorable in it being 10 micrometers or less.

The particle size distribution and average particle size of the spherical particles can be measured by the following method.

Measurement of spherical particle size distribution and average particle size Film adhesive 103 is placed in a crucible and ignited to incinerate film adhesive 103. The obtained ash was dispersed in pure water and subjected to ultrasonic treatment for 10 minutes, and the particle size distribution (volume basis) using a laser diffraction / scattering particle size distribution analyzer (“LS 13 320” manufactured by Beckman Coulter, Inc .; wet method). ) And average particle size.

The content of the conductive particles in the film adhesive 103 is preferably 30% by weight or more, more preferably 40% by weight or more, still more preferably 60% by weight or more, and particularly preferably 70% by weight or more. If it is less than 30% by weight, it tends to be difficult to form a conductive path. Further, the content of the conductive particles is preferably 95% by weight or less, more preferably 94% by weight or less. If it exceeds 95% by weight, film formation tends to be difficult. Moreover, there exists a tendency for adhesive force to fall.

In addition to the above components, the film adhesive 103 may appropriately contain a compounding agent generally used in film production, such as a crosslinking agent.

The film adhesive 103 can be manufactured by a normal method.

Although the thickness of the film adhesive 103 is not specifically limited, 5 micrometers or more are preferable and 15 micrometers or more are more preferable. When the thickness is less than 5 μm, a portion where the warped semiconductor wafer or the semiconductor chip does not adhere may occur, and the adhesion area may become unstable. The thickness of the film adhesive 103 is preferably 100 μm or less, and more preferably 50 μm or less. When the thickness exceeds 100 μm, the film adhesive 103 may protrude excessively due to the load of die attachment, and the pad may be contaminated.

The surface roughness (Ra) of the film adhesive 103 is preferably 0.1 to 5000 nm. If it is less than 0.1 nm, it is difficult to blend. On the other hand, if it exceeds 5000 nm, the adherence to the adherend during die attachment may be reduced.

The electrical resistivity of the film adhesive 103 is preferably as low as possible, for example, 9 × 10 ⁻² Ω · m or less. When it is 9 × 10 ⁻² Ω · m or less, the electroconductivity is good and it is possible to cope with small size and high density mounting. On the other hand, the electrical resistivity is preferably 1 × 10 ⁻⁶ Ω · m or more.

The higher the thermal conductivity of the film adhesive 103, the better. For example, it is 0.5 W / m · K or more. When it is 0.5 W / m · K or more, the heat dissipation is good, and it is possible to cope with small and high-density mounting. On the other hand, if it is less than 0.5 W / m · K, heat dissipation is poor, heat is accumulated, and the conductivity may be deteriorated.

The tensile storage elastic modulus at 120 ° C. of the film adhesive 103 is preferably 10 MPa or less, more preferably 5 MPa or less. When it is 10 MPa or less, the fluidity of the film adhesive 103 near the thermosetting temperature is high, and it is easy to eliminate voids by heating under pressure. The tensile storage modulus at 120 ° C. is preferably 0.01 MPa or more, more preferably 0.05 MPa or more. If it is 0.01 MPa or more, the film adhesive 103 is difficult to protrude.
The tensile storage elastic modulus at 120 ° C. can be measured by the following method.

Measurement of tensile storage modulus at 120 ° C. A strip-shaped measurement piece having a length of 30 mm, a width of 10 mm, and a thickness of 400 μm is cut out from the film-like adhesive 103. Using a fixed viscoelasticity measuring apparatus (RSA-II, manufactured by Rheometric Scientific), the measurement piece was measured for a chuck storage width of 22.6 mm, a tensile storage elastic modulus at 0 ° C. to 200 ° C. with a frequency of 1 Hz, and a temperature increase rate of 10 Measure under conditions of ° C / min.

The tensile storage modulus at 120 ° C. can be controlled by the glass transition temperature of the thermoplastic resin, the blending amount of conductive particles, and the like. For example, by blending a thermoplastic resin having a low glass transition temperature, the tensile storage elastic modulus at 120 ° C. can be lowered.

The film adhesive 103 is preferably used in the form of a dicing tape with a film adhesive.

As shown in FIG. 5, the dicing tape 110 with a film adhesive includes a dicing tape 101 and a film adhesive 103 disposed on the dicing tape 101. The dicing tape 101 includes a base material 111 and an adhesive layer 112 disposed on the base material 111. The film adhesive 103 is disposed on the pressure-sensitive adhesive layer 112.

As shown in FIG. 6, the dicing tape 110 with a film adhesive may have a configuration in which the film adhesive 103 is formed only on a work (semiconductor wafer 104 or the like) attachment portion.

Since the description about the base material 111 is the same as the description about the base material 1, it is omitted. Since the description about the adhesive layer 112 is the same as the description about the adhesive layer 112, it abbreviate | omits.

The peeling force when the film adhesive 103 is peeled off from the dicing tape 101 under the conditions of a peeling temperature of 25 ° C. and a peeling speed of 300 mm / min is preferably 0.01 to 3.00 N / 20 mm. If it is less than 0.01 N / 20 mm, there is a risk of chip jumping during dicing. On the other hand, if it exceeds 3.00 N / 20 mm, the pickup tends to be difficult.

A method for manufacturing a semiconductor device will be described.

As shown in FIG. 7, a dicing tape 110 with a film adhesive is pressure-bonded to the semiconductor wafer 104. Examples of the semiconductor wafer 104 include a silicon wafer, a silicon carbide wafer, and a compound semiconductor wafer. Examples of compound semiconductor wafers include gallium nitride wafers.

Examples of the crimping method include a method of pressing with a pressing means such as a crimping roll.

The pressing temperature (sticking temperature) is preferably 35 ° C. or higher, and more preferably 37 ° C. or higher. The upper limit of the pressure bonding temperature is preferably lower, preferably 50 ° C. or lower, more preferably 45 ° C. or lower. By press-bonding at a low temperature, it is possible to prevent a thermal effect on the semiconductor wafer 104 and suppress warping of the semiconductor wafer 104.

The pressure is preferably 1 × 10 ⁵ Pa to 1 × 10 ⁷ Pa, and more preferably 2 × 10 ⁵ Pa to 8 × 10 ⁶ Pa.

Next, as shown in FIG. 8, the semiconductor wafer 104 is diced. That is, the semiconductor wafer 104 is cut into a predetermined size and separated into pieces, and the semiconductor chip 105 is cut out. Dicing is performed according to a conventional method. Further, in this step, for example, a cutting method called full cut in which cutting is performed up to the dicing tape 110 with a film adhesive can be employed. It does not specifically limit as a dicing apparatus used at this process, A conventionally well-known thing can be used. Moreover, since the semiconductor wafer 104 is bonded and fixed by the dicing tape 110 with a film adhesive, chip chipping and chip jump can be suppressed, and damage to the semiconductor wafer 104 can be suppressed.

In order to peel off the semiconductor chip 105 bonded and fixed to the dicing tape 110 with a film adhesive, the semiconductor chip 105 is picked up. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, there is a method in which each semiconductor chip 105 is pushed up by a needle from the dicing tape 110 with film adhesive, and the pushed-up semiconductor chip 105 is picked up by a pickup device.

Here, when the pressure-sensitive adhesive layer 112 is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 112 is irradiated with ultraviolet rays. Thereby, the adhesive force with respect to the film adhesive 103 of the adhesive layer 112 falls, and peeling of the semiconductor chip 105 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip 105. Conditions such as irradiation intensity and irradiation time at the time of ultraviolet irradiation are not particularly limited, and may be set as necessary.

As shown in FIG. 9, the picked-up semiconductor chip 105 is bonded and fixed to the adherend 106 through the film adhesive 103 to obtain the adherend 161 with the semiconductor chip. The adherend with semiconductor chip 161 includes an adherend 106, a film adhesive 103 disposed on the adherend 106, and a semiconductor chip 105 disposed on the film adhesive 103.

Subsequently, the film-shaped adhesive 103 is thermally cured by heating the adherend with semiconductor chip 161 under pressure to fix the semiconductor chip 105 and the adherend 106. By thermally curing the film adhesive 103 under pressure, voids existing between the film adhesive 103 and the adherend 106 can be eliminated, and the film adhesive 103 can be removed from the adherend 106. The area in contact with can be secured.

Examples of the method of heating under pressure include a method of heating the adherend with semiconductor chip 161 disposed in a chamber filled with an inert gas.
The pressure of the pressurized atmosphere is preferably 0.5 kg / cm ² (4.9 × 10 ⁻² MPa) or more, more preferably 1 kg / cm ² (9.8 × 10 ⁻² MPa) or more, and further preferably 5 kg. / Cm ² (4.9 × 10 ⁻¹ MPa) or more. If it is 0.5 kg / cm ² or more, voids existing between the film adhesive 103 and the adherend 106 can be easily eliminated. The pressure of the pressurized atmosphere is preferably 20kg ^/ cm 2 (1.96MPa), more preferably 18kg ^/ cm 2 (1.77MPa) or less, more preferably not more than 15kg ^/ cm 2 (1.47MPa). If it is 20 kg / cm ² or less, the protrusion of the film adhesive 103 due to excessive pressurization can be suppressed.

The heating temperature when heating under pressure is preferably 80 ° C or higher, more preferably 100 ° C or higher, still more preferably 120 ° C or higher, and particularly preferably 170 ° C or higher. When the temperature is 80 ° C. or higher, the film-like adhesive 103 can have an appropriate hardness, and voids can be effectively eliminated by pressure curing.
The heating temperature is preferably 260 ° C. or lower, more preferably 200 ° C. or lower, more preferably 180 ° C. or lower. It can prevent decomposition | disassembly of the film adhesive 103 before hardening as it is 260 degrees C or less.

The heating time is preferably 0.1 hour or longer, more preferably 0.2 hour or longer, and further preferably 0.5 hour or longer. When it is 0.1 hour or longer, the effect of pressurization can be sufficiently obtained. The heating time is preferably 24 hours or less, more preferably 3 hours or less, and even more preferably 1 hour or less.

As shown in FIG. 10, a wire bonding process is performed in which the tip of the terminal portion (inner lead) of the adherend 106 and an electrode pad (not shown) on the semiconductor chip 105 are electrically connected by a bonding wire 107. As the bonding wire 107, for example, a gold wire, an aluminum wire or a copper wire is used. The temperature during wire bonding is preferably 80 ° C. or higher, more preferably 120 ° C. or higher, and the temperature is preferably 250 ° C. or lower, more preferably 175 ° C. or lower. The heating time is several seconds to several minutes (for example, 1 second to 1 minute). The connection is performed by a combination of vibration energy by ultrasonic waves and pressure energy by pressurization while being heated so as to be within the temperature range.

Subsequently, a sealing process for sealing the semiconductor chip 105 with the sealing resin 108 is performed. This step is performed to protect the semiconductor chip 105 and the bonding wire 107 mounted on the adherend 106. This step is performed by molding a sealing resin with a mold. As the sealing resin 108, for example, an epoxy resin is used. The heating temperature at the time of resin sealing is preferably 165 ° C. or higher, more preferably 170 ° C. or higher, and the heating temperature is preferably 185 ° C. or lower, more preferably 180 ° C. or lower.

If necessary, the sealed material may be further heated (post-curing step). Thereby, the insufficiently cured sealing resin 108 can be completely cured in the sealing process. The heating temperature can be set as appropriate.

As described above, after the step of die-bonding the semiconductor chip 105 on the adherend 106 and the step of die-bonding the semiconductor chip 105 on the adherend 106 via the film-like adhesive 103, the film-like adhesive 103 is applied. A semiconductor device is manufactured by a method including a step of thermosetting by heating under pressure. That is, after the step of pressing a die bonding chip including the film adhesive 103 and the semiconductor chip 105 in contact with the film adhesive 103 to the adherend 106 and the step of pressing the die bonding chip to the adherend 106, the film A semiconductor device is manufactured by a method including a step of thermosetting by heating the adhesive 103 under pressure.

More specifically, such a method includes a step of placing the semiconductor wafer 104 on the film adhesive 103 of the dicing tape 110 with a film adhesive, and a dicing of the semiconductor wafer 104 placed on the film adhesive 103. Forming the semiconductor chip 105, picking up the semiconductor chip 105 together with the film adhesive 103, die bonding the semiconductor chip 105 on the adherend 106 via the film adhesive 103, After the step of die-bonding the semiconductor chip 105 on the adherend 106, a step of thermally curing the film adhesive 103 by heating it under pressure is included.

The third invention has been described above.

Hereinafter, the first, second, and third aspects of the present invention will be described in detail using examples. However, the first, second, and third aspects of the present invention are limited to the following examples as long as they do not exceed the gist thereof. Is not to be done. In each example, all parts are based on weight unless otherwise specified.

[First and Second Embodiments of the Invention]
The components used in the examples will be described.
Arontack S-2060: Arontack S-2060 (acrylic copolymer, Mw: 550,000, glass transition temperature: −22 ° C.) manufactured by Toa Gosei Co., Ltd.
Teisan resin SG-70L: Teisan resin SG-70L manufactured by Nagase ChemteX Corporation (acrylic copolymer, Mw: 900,000, glass transition temperature: −13 ° C.)
EOCN-1020-4: EOCN-1020-4 manufactured by Nippon Kayaku Co., Ltd. (solid epoxy resin at 25 ° C.)
JER828: JER828 manufactured by Mitsubishi Chemical Corporation (epoxy resin which is liquid at 25 ° C)
MEH-7851SS: MEH-7851SS (phenol aralkyl resin) manufactured by Meiwa Kasei Co., Ltd.
1400YM: 1400YM manufactured by Mitsui Mining & Smelting Co., Ltd. (copper powder, spherical, average particle size 4 μm, specific gravity 8.9)
1300YM: 1300YM manufactured by Mitsui Mining & Smelting Co., Ltd. (copper powder, spherical, average particle size 3 μm, specific gravity 8.9)
ES-6000: ES-6000 (Silver glass beads, spherical shape, average particle diameter 6 μm, specific gravity 3.9 to 4.0) manufactured by Potters Parrotini Co., Ltd.
AUP-1000: AUP-1000 manufactured by Osaki Kogyo Co., Ltd. (gold powder, spherical, average particle size 1 μm, specific gravity 19.3)
1200YP: 1200YP manufactured by Mitsui Mining & Smelting Co., Ltd. (flaked copper powder, average particle size 3.5 μm, aspect ratio: 10, specific gravity 8.9)
1050YP: 1050YP manufactured by Mitsui Mining & Smelting Co., Ltd. (flaked copper powder, average particle size 0.9 μm, aspect ratio: 4, specific gravity 8.9)
1400YP: 1400YP manufactured by Mitsui Mining & Smelting Co., Ltd. (flaked copper powder, average particle size: 7.0 μm, aspect ratio: 25, specific gravity: 8.9)
SPQ01: SPQ01 (silver powder, spherical shape, average particle size 0.1 μm, specific gravity 10.5) manufactured by Mitsui Mining & Smelting Co., Ltd.
EHD: EHD manufactured by Mitsui Mining & Smelting Co., Ltd. (silver powder, spherical, average particle size 0.7 μm, specific gravity 10.5)

[Production of film adhesive and dicing tape with film adhesive]
(Examples and Comparative Examples)
In accordance with the mixing ratios shown in Tables 1 and 2, the components and the solvent (methyl ethyl ketone) shown in Tables 1 and 2 were placed in a stirring vessel of a hybrid mixer (Keyence HM-500). Mixed. The obtained varnish was applied to a release treatment film (MRA50 manufactured by Mitsubishi Resin Co., Ltd.) with a die coater and then dried to produce a film adhesive.

The obtained film adhesive was cut into a circle having a diameter of 230 mm and pasted on a pressure-sensitive adhesive layer of a dicing tape (P2130G manufactured by Nitto Denko Corporation) at 25 ° C. to prepare a dicing tape with a film adhesive. .

[Production of mirror silicon wafer]
Using a back grinder (DFG-8560 manufactured by DISCO Corporation), the silicon wafer (Shin-Etsu Chemical Co., Ltd., thickness 0.6 mm) is ground to a thickness of 0.05 mm, and the mirror silicon wafer is Produced.

[Evaluation]
The following evaluation was performed using the obtained film adhesive, dicing tape with film adhesive, and mirror silicon wafer. The results are shown in Tables 1-2.

[Adhesion evaluation]
Using a wafer mounter (MA-3000III manufactured by Nitto Seiki Co., Ltd.), mirror silicon on the film adhesive of the dicing tape with film adhesive at an application speed of 10 mm / min and an application temperature of 40 ° C. The wafer was bonded.
What was obtained by the bonding was diced into 10 mm × 10 mm □ using a dicer (DFD-6361 manufactured by DISCO Corporation) to obtain individual pieces. A die bonder (SPA-300, manufactured by Shinkawa Co., Ltd.) was used to die attach individual pieces (chips and pieces made of film adhesive) to a lead frame at 120 ° C., 0.1 MPa, and 1 second. After die attachment, the side surface of the piece was observed with a scanning electron microscope. If there was no gap between the piece and the lead frame, it was judged as “No”, and if there was a gap, it was judged as “Yes”.

[Projection evaluation]
Using a wafer mounter (MA-3000III manufactured by Nitto Seiki Co., Ltd.), mirror silicon on the film adhesive of the dicing tape with film adhesive at an application speed of 10 mm / min and an application temperature of 40 ° C. The wafer was bonded.
What was obtained by the bonding was diced into 10 mm × 10 mm □ using a dicer (DFD-6361 manufactured by DISCO Corporation) to obtain individual pieces. Using a die bonder (SPA-300 manufactured by Shinkawa Co., Ltd.), individual pieces (individual pieces made of chip and film adhesive) were die-attached to a lead frame at 120 ° C., 0.4 MPa, and 1 second. The individual pieces were observed from the upper surface using an optical microscope after die attachment, and the distance (excess distance) at which the film adhesive protruded from the end surface of the chip was measured.

[Measurement of peel strength between film adhesive and dicing tape]
A polyester pressure-sensitive adhesive tape (BT-315 manufactured by Nitto Denko Corporation) is bonded to the film adhesive of the dicing tape with film adhesive, and then cut into a width of 100 mm x 100 mm to prepare a sample. did. About this sample, the film adhesive was peeled from the dicing tape at a peeling speed of 300 mm / min and a peeling temperature of 25 ° C. with a T peel, and the peeling force was measured.

[Measurement of volume resistivity]
For the film adhesive, volume resistivity was measured by a four-probe method based on JIS K 7194 using a resistivity meter (Loresta MP MCP-T350 manufactured by Mitsubishi Chemical Corporation).

[Measurement of particle size distribution and average particle size of conductive particles]
The film adhesives of Example 2, Example 6, Comparative Example 5 and Comparative Example 6 were put in a crucible and ignited to ash the film adhesive. The obtained ash was dispersed in pure water and subjected to ultrasonic treatment for 10 minutes, and the particle size distribution (volume basis) using a laser diffraction / scattering particle size distribution analyzer (“LS 13 320” manufactured by Beckman Coulter, Inc .; wet method). ) And average particle size. Note that the composition of the film adhesive is an organic component other than the conductive particles, and substantially all the organic components are burned off by the above-described strong heat treatment, so the ash obtained is regarded as the conductive particles for measurement. It was.

[Comprehensive judgment]
The case where all the following conditions were satisfied was determined as “good”, and the case where any one of the following conditions was not satisfied was determined as “poor”.
Condition (1): The determination result of the adhesion evaluation is “none”.
Condition (2): The protrusion distance measured by the protrusion evaluation is 100 μm or less.
Condition (3): The measurement result of the peel force measurement between the film adhesive and the dicing tape is 0.01 to 3.00 N / 20 mm.
Condition (4): The volume resistivity of the film adhesive is 1 × 10 ⁻⁶ Ω · m or more and 9 × 10 ⁻² Ω · m or less.

In Example 1, Examples 3 to 5, and Example 7 using a film adhesive containing plate-like particles having an aspect ratio of 5 or more, excellent conductivity was obtained. On the other hand, in Comparative Example 4 using a film adhesive containing plate-like particles having an aspect ratio of 4, the conductivity was inferior.

In Example 2 and Example 6 using a film adhesive containing two kinds of spherical particles, excellent conductivity was obtained. On the other hand, Comparative Examples 1 to 3 and Comparative Examples 5 to 6 using a film adhesive containing one kind of spherical particles were inferior in conductivity.

In addition, about the ash content of the film adhesive of Example 2, Example 6, Comparative Example 5, and Comparative Example 6, the particle size distribution and the average particle size were measured. This measurement result was substantially the same as the value calculated from the average particle size of the conductive particles.

Heretofore, the first and second embodiments according to the present invention have been described.

[Third embodiment of the present invention]

The components used in the examples will be described.
Teisan Resin SG-70L: Teisan Resin SG-70L manufactured by Nagase ChemteX Corporation (acrylic copolymer containing a carboxyl group, Mw: 900,000, acid value: 5 mgKOH / g, glass transition temperature: −13 ° C.)
EOCN-1020-4: EOCN-1020-4 manufactured by Nippon Kayaku Co., Ltd. (solid epoxy resin at 25 ° C.)
JER828: JER828 manufactured by Mitsubishi Chemical Corporation (epoxy resin which is liquid at 25 ° C)
MEH-7851SS: MEH-7851SS (phenol aralkyl resin) manufactured by Meiwa Kasei Co., Ltd.
1400YM: 1400YM manufactured by Mitsui Mining & Smelting Co., Ltd. (copper powder, spherical, average particle size 4 μm, specific gravity 8.9)
1200YP: 1200YP manufactured by Mitsui Mining & Smelting Co., Ltd. (flaked copper powder, average particle size 3.5 μm, aspect ratio: 10, specific gravity 8.9)
EHD: EHD manufactured by Mitsui Mining & Smelting Co., Ltd. (silver powder, spherical, average particle size 0.7 μm, specific gravity 10.5)

[Production of film adhesive and dicing tape with film adhesive]
(Examples 8 to 10 and Comparative Examples 7 to 9)
In accordance with the blending ratios described in Tables 3 to 4, the components and solvents (methyl ethyl ketone) described in Tables 3 to 4 were placed in a stirring vessel of a hybrid mixer (Keyence HM-500) and stirred in 3 minutes. Stir and mix. The obtained varnish was applied to a release treatment film (MRA50 manufactured by Mitsubishi Resin Co., Ltd.) with a die coater and then dried to produce a film adhesive.

[Evaluation]
The following evaluation was performed about the obtained film adhesive and the dicing tape with a film adhesive. The results are shown in Tables 3-4.

[Adhesion area]
(Evaluation method of Examples 8 to 10)
Using a wafer mounter (MA-3000III manufactured by Nitto Seiki Co., Ltd.), mirror silicon on the film adhesive of the dicing tape with film adhesive at an application speed of 10 mm / min and an application temperature of 40 ° C. The wafer was bonded.
A mirror silicon wafer placed on a dicing tape with a film adhesive is diced (divided into 10 mm × 10 mm □) using a dicer (DFD-6361 manufactured by DISCO Corporation) to obtain individual pieces. It was. Using a die bonder (SPA-300 manufactured by Shinkawa Co., Ltd.), the pieces were die-attached to the lead frame via a film adhesive at 120 ° C., 0.1 MPa, and 1 second. After the die attach, pressure curing was performed under the conditions shown in Table 3 using a pressure curing furnace (MODEL AC manufactured by Iwata Manufacturing Co., Ltd.). After curing, the adhesion area where the film adhesive adhered to the lead frame was observed using an ultrasonic microscope. The case where the adhesion area was 95% or more was judged as ◯, and the case where it was less than 95% was judged as x. In addition, regarding the bonding area, the larger the percentage value, the fewer voids exist between the film adhesive and the lead frame.
(Evaluation method of Comparative Examples 7 to 9)
The same method as in Examples 8 to 10 except that pressureless curing was performed under the conditions shown in Table 4 using a dryer (STC-120H manufactured by Espec Co., Ltd.) instead of the pressure curing furnace. The adhesion area was evaluated.

The embodiment according to the third aspect of the present invention has been described above.

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive layer 3 Film adhesive 4 Semiconductor wafer 5 Semiconductor chip 6 Substrate 7 Bonding wire 8 Sealing resin 10 Dicing tape 11 with film adhesive 11 Dicing tape

DESCRIPTION OF SYMBOLS 110 Dicing tape with a film adhesive 101 Dicing tape 111 Base material 112 Adhesive layer 103 Film adhesive 104 Semiconductor wafer 105 Semiconductor chip 106 Adhering body 161 Adhering body with a semiconductor chip 107 Bonding wire 108 Sealing resin

Claims

Containing conductive particles,
The conductive particles are at least one selected from the group consisting of gold particles, silver particles, copper particles and coated particles,
The coated particle comprises a core particle and a coating film that coats the core particle,
The coating film includes at least one selected from the group consisting of gold, silver and copper,
The conductive particles include plate-like particles having an aspect ratio of 5 or more,
A film adhesive in which the content of the plate-like particles in 100% by weight of the conductive particles is 5% by weight to 100% by weight.
The film adhesive according to claim 1, wherein the content of the conductive particles in the film adhesive is 30 wt% to 95 wt%.
The film adhesive according to claim 1 or 2, wherein the volume resistivity is 1 × 10 −6 Ω · m or more and 9 × 10 −2 Ω · m or less.
A dicing tape with a film adhesive, comprising: a dicing tape; and the film adhesive according to any one of claims 1 to 3 laminated on the dicing tape.
A method for manufacturing a semiconductor device, comprising a step of die-attaching a semiconductor chip to an adherend using the film adhesive according to any one of claims 1 to 3.
Containing conductive particles,
The conductive particles are at least one selected from the group consisting of gold particles, silver particles, copper particles and coated particles,
The coated particle comprises a core particle and a coating film that coats the core particle,
The coating film includes at least one selected from the group consisting of gold, silver and copper,
The conductive particles include spherical spherical particles,
In the particle size distribution of the spherical particles, there are two or more peaks,
Peak A exists in the particle size range of 0.2 μm to 0.8 μm, and Peak B exists in the particle size range of 3 μm to 15 μm,
A film adhesive in which the ratio of the particle size of the peak B to the particle size of the peak A is 5 to 15.
The film adhesive according to claim 6, wherein the content of the conductive particles in the film adhesive is 30% by weight to 95% by weight.
The film adhesive according to claim 6 or 7, wherein the volume resistivity is 1 × 10 −6 Ω · m or more and 9 × 10 −2 Ω · m or less.
A dicing tape with a film adhesive, comprising: a dicing tape; and the film adhesive according to any one of claims 6 to 8 laminated on the dicing tape.
A method for manufacturing a semiconductor device, comprising a step of die-attaching a semiconductor chip to an adherend using the film adhesive according to any one of claims 6 to 8.