JPS62121781A - Adhesive sheet for wafer dicing - Google Patents

Abstract

PURPOSE:To obtain the titled sheet having excellent strength and processability in a dicing process, by providing a self-adhesive layer on a butene polymer film. CONSTITUTION:A butene polymer (e.g., polybutene) is formed to give a film having a thickness of 30-200mum and, according to JIS K6781, a tensile modulus of 800-6,000kg/cm<2>, a stress at break of 150-700kg/cm<2>, an elongation at break of 150-600%, and a stress at 100% elongation of 50-300kg/cm<2>. A pressure-sensitive adhesive substance is uniformly applied or transferred in a thickness of 10-25mum to the surface of this film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a film for dicing semiconductor wafers.

[Conventional technology]

2. Description of the Related Art As a method for manufacturing semiconductor pellets, a method is known in which a semiconductor wafer on which a large number of semiconductor elements are formed is diced (cut) into pellets containing each element. In this case, as described in JP-A-58-147044, a semiconductor wafer with dicing grooves formed with a diamond blade or the like is adhered to an appropriate film, and the uncut portions of the dicing grooves are removed by pressing with a roller or the like. The mutually separated pellets are taken out individually by mechanical means such as cutting and pushing up from below the film.

As this dicing film,
No. 7044 proposes a flexible vinyl film with adhesive properties made by adding a plasticizer to a vinyl chloride copolymer. In addition, polyolefin films such as polyethylene, polyester films, and polystyrene films with adhesive layers formed on their surfaces are also used.

[Problem that the invention seeks to solve]

Although the conventionally used soft vinyl chloride film with self-adhesive properties has excellent stretchability as described below, it has the disadvantage that the plasticizer contained therein migrates to the wafer and contaminates it. Residual vinyl chloride monomer also has the disadvantage of contaminating the wafer. In addition, the other films described above have a disadvantage in that, since the film has poor stretchability, the workability is poor, such as the step of pushing up from below the film to take out the pellets individually after cutting the wafer.

[Means for solving problems]

The present inventors studied a film for dicing that has the strength necessary for dicing and does not have the above-mentioned drawbacks, and found that the following film was suitable, and completed the present invention.

That is, the present invention is a film for semiconductor wafer dicing, which is formed by laminating an adhesive layer on a butene-based polymer film.

Although JP-A-59-177943 describes that a polyolefin film such as that of the present invention can be used, there are no specific examples thereof, and there is no suggestion of a butene-based polymer at all. Not listed.

[Butene-based polymer]

As the butene-based polymer used in the film of the present invention, in addition to a homopolymer of 1-butene, a copolymer of 1-butene, ethylene, propylene, or an α-olefin having a Ct or higher can be used.

A copolymer containing two or more of these monomers other than 1-butene may also be used. 05 or more −
Examples of the α-olefin include 1-pentene, 1-hexane, 1-decene, 4-methyl-1-pentyne, and 3-methyl-1-pentene. Preferred is 4-methyl-1-pentene.

Here, particularly in the copolymer of 1-butene and ethylene, one having an ethylene content of 12 mol% or less is usually used, preferably 3 mol% or less. Also 1
- In the copolymer of butene and propylene, one having a propylene content of 35 mol% or less is usually used, preferably 20 mol% or less. Further, in a copolymer of 1-butene and an α-olefin having a Cs or higher, the content of the acid α-olefin is usually 35 mol% or less, preferably 15 mol% or less. If it exceeds the above range, the blow moldability and other formability of the film will be poor, so it is preferably within the above range.

In addition to the butene-based polymer, the butene-based polymer used in the present invention includes other olefin-based polymers such as polyethylene, polypropylene, ethylene/propylene copolymer,
Ethylene/1-butene copolymers, propylene/1-butene copolymers (in these copolymers, the 1-butene content is 50 mol% or less), etc. are used to improve the mechanical properties of films such as rigidity. It may be added for the purpose of In this case, the amount added is usually 40 wt% or less, preferably 20 wt% or less.

Other properties of the butene copolymer used in the present invention include M
F R (ASTM D1238B 5190°C) is 0.
01 to 30, preferably 0.1 to 10 g/10 m1n.

[Butene-based polymer]

The butene-based polymer film used in the present invention can be prepared by molding the butene-based polymer using the inflation molding method, the blow molding method, or the T.
- It is molded by a molding method commonly used for molding films, such as a die molding method.

The preferred properties of the film include a thickness of 30 to 20
0. crm, tensile modulus 8 according to JISK6781
00 to 6000kg/ci Stress at break 150 to 700kg/ctA Elongation at break 150 to 600
%, 100% elongation stress is 50 to 300 kg/cal.

[Adhesive layer]

The adhesive layer laminated on the film of the present invention is sufficient to fix the wafer, and after the wafer is cut, it can be used without contaminating (separating) the pellets in the above-mentioned pushing-off and separation process of the semiconductor pellets. Any pressure-sensitive adhesive material that has been used in the past can be used as is.

However, it is preferable to use one that does not contain a plasticizer such as that added to vinyl chloride resin. Something like this - for example:
Examples include those consisting of a block copolymer described in JP-A-59-177943, another rubber component, and a tackifying resin. In this case, other rubber components are not necessarily required depending on the block copolymer used. As the film of the present invention, it is preferable to use an adhesive layer mainly composed of a block copolymer used in JP-A-59-177943.

The pressure-sensitive adhesive layer made of the above-mentioned pressure-sensitive adhesive material is coated on the above-mentioned butene-based polymer film to a thickness of 1.
Uniformly coated or transferred in the range of 0 to 25 μm,
The film for semiconductor wafer dicing of the present invention is manufactured.

〔Effect of the invention〕

By using the dicing film of the present invention, the workability of the dicing process is improved because the wafer is not contaminated and the film has excellent stretchability.

[Example], Example 1 Styrene-isoprene-styrene block copolymer rubber (styrene/isoprene = 14/86 heavy fil ratio, Shell chemical type "Krayton G1657J > 27 heavy M parts, petroleum resin (Mitsui Petrochemical Co., Ltd.) “Highlets T-300
XJ) 3 parts by weight of a pressure-sensitive adhesive material with a thickness of 1
The adhesive film for wafer dicing of the present invention was obtained by coating a 00 μm polybutene film with a thickness of 10 μm.

In order to evaluate the characteristics of such an adhesive film for wafer dicing, the following tests were conducted.

(1) Tensile properties JI of adhesive film for wafer dicing
A test piece similar to the four-bow dumbbell test piece described in S K6301-1975, total length 50 mm, width at both ends 10 mm, chuck distance 30 mm, parallel part length 15 mm, parallel part width 51, The thickness of the parallel part is 0.
08n+m, R is 12mm, gauge distance is 15
mm test piece, test temperature 23℃, test speed 5
The tensile modulus, stress at break, elongation at break, and 100% elongation stress were determined according to JIS K6781 under the condition of 0 m+/min.

(2) Wafer adhesive residual test Fix the adhesive film for wafer dicing to the wafer,
After heating at 0°C for 30 minutes, the wafer was peeled off, and the presence or absence of any adhesive remaining on the wafer was examined under a 50x magnification microscope.

(3) CZ- remaining on the wafer after the wafer metal ion (C1-) residual test vs. wafer adhesive residual test was subjected to AI K=c line excitation (8 KV-30 mA) using Shimabara Manufacturing ESCA-750. The analysis was carried out.

The above results are listed in Table 1.

Comparative Example 1 20% dioctyl phthalate (DOP) as a plasticizer
A test was conducted according to Example 1 except that a film containing vinyl chloride (Zeon 103EP J film (thickness 100 μm) manufactured by Nippon Zeon Co., Ltd. was used as the adhesive film for wafer dicing. The results are shown in Table 1.

Comparative Example 2 The adhesive described in Example 1 was applied to a PE film (thickness 100 μm) (thickness 10 μm), and the same test was conducted. The results are shown in Table 1.

Claims (1)

[Claims] (1) A film for semiconductor wafer dicing, which is made by laminating an adhesive layer on a butene-based polymer film.