JP2024002081A - Manufacturing method of ruthenium-containing thin film - Google Patents

Abstract

To provide a manufacturing method capable of more easily manufacturing a ruthenium-containing thin film in a region selective manner by a CVD method or an ALD method.SOLUTION: A manufacturing method of a ruthenium-containing thin film by a CVD method or an ALD method using a ruthenium compound as a raw material manufactures the ruthenium-containing thin film in a region selective manner using a ruthenium compound and one or more types of a reduction gas.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a metal-containing thin film using a metal complex useful as a raw material for manufacturing semiconductor devices.

Ruthenium has features such as high conductivity, the ability to form conductive oxides, a high work function, excellent etching properties, and excellent lattice matching with copper. It is attracting attention as a material for memory electrodes, gate electrodes, copper wiring seed layers/adhesion layers, etc. of DRAM, etc. Next-generation semiconductor devices are employing highly detailed and three-dimensional designs to further improve storage capacity and responsiveness. Therefore, in order to use ruthenium as a material constituting next-generation semiconductor devices, it is necessary to establish a technology to uniformly form a ruthenium-containing thin film with a thickness of several nanometers to several tens of nanometers on a three-dimensional substrate. is necessary. Technologies for manufacturing ruthenium-containing thin films on three-dimensional substrates include the use of chemical reaction-based vapor deposition methods, such as atomic layer deposition (ALD) and chemical vapor deposition (CVD). is considered to be the most likely.

In semiconductor device manufacturing, in order to form a thin film by CVD or ALD, a material is selected that has appropriate vaporization characteristics and thermal stability and can be vaporized in a stable supply amount. Another necessary condition is the ability to form a thin film with a uniform thickness on the surface of a complex three-dimensional structure. Furthermore, in order to vaporize at a stable supply amount, it is preferable that the gas be in a liquid state at the time of supply.

Bis(ethylcyclopentadienyl)ruthenium and (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -ethylcyclopentadienyl) are used as raw materials for forming a ruthenium-containing thin film by the CVD method or the ALD method. The use of divalent ruthenium compounds such as ruthenium and (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium is being considered.

J. Phys. Chem. C 2014, 118, 10957-10962 ACS NANO Vol. 9, No. 9, 8710-8717 (2015)

Japanese Patent Application Publication No. 2021-105196 JP2022-017896A

In recent years, with the miniaturization of semiconductor devices, there has been a demand for technology for forming fine patterns of 30 nm or less. However, the conventional lithography method has become technically difficult due to optical factors and other factors. Therefore, a method has been proposed in which a pattern is formed by directly and region-selectively manufacturing a film on a substrate using a CVD method or an ALD method. (See Non-Patent Documents 1 and 2, Patent Documents 1 and 2)
For example, by treating two or more substrate regions of different materials with a surface treatment agent, only one region can be selectively chemically modified to have blocking performance against ALD or CVD methods, and the other region can be selectively modified with blocking performance against ALD or CVD methods. Techniques for region-selectively manufacturing membranes only in this region have been reported. However, in order to modify the substrate surface using such a method, in addition to the process of adsorbing the surface treatment agent to the substrate surface and treating it, there is also a removal process of removing the treatment agent adsorbed to the substrate surface by heating, etc. There is a disadvantage that it occurs additionally.

Therefore, an object of the present invention is to provide a manufacturing method that can more easily manufacture a membrane in a region-selective manner.

In view of the above-mentioned current situation, the present inventors have conducted intensive studies and found that by using a ruthenium compound as a raw material and forming a film under specific reaction conditions by the CVD method or ALD method, ruthenium can be contained selectively in regions. They discovered a method for manufacturing thin films and completed the present invention.

That is, the present invention includes the following embodiments.

[1] A method for producing a ruthenium-containing thin film by a CVD method or an ALD method using a ruthenium compound as a raw material, in which a ruthenium compound and one or more types of reducing gas are used to selectively form a ruthenium-containing thin film. A method for producing a ruthenium-containing thin film.

[2] The ruthenium compound has the general formula (1AB)

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ³ , R ⁴ and Z each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Z represents an oxygen atom or CH.) The method for producing a ruthenium-containing thin film according to the above [1].

[3] The ruthenium-containing thin film according to the above [2], wherein R ¹ and R ² are alkyl groups having 1 to 4 carbon atoms, R ³ and R ⁴ are methyl groups, and Z is an oxygen atom or CH. Production method.

[4] Production of the ruthenium-containing thin film according to [2] above, wherein R ¹ is an ethyl group, R ² is a hydrogen atom, R ³ and R ⁴ are methyl groups, and Z is an oxygen atom or CH Method.

[5] The method for producing a ruthenium-containing film according to any one of [1] to [4] above, using ammonia gas as the reducing gas.

[6] The method for producing a ruthenium-containing thin film according to any one of [1] to [4] above, using both ammonia gas and hydrogen gas as the reducing gas.

[7] A set for producing a region-selective ruthenium-containing thin film, which includes a ruthenium compound and one or more types of reducing gas.

By the manufacturing method of the present invention, a ruthenium-containing thin film can be manufactured in a region-selective manner.

1 is a diagram showing a CVD apparatus used in Examples 1 to 6 and Comparative Examples 1 and 2. FIG.

The present invention will be explained in more detail below.

First, the ruthenium compound used as a raw material will be explained.

Examples of the ruthenium compound include a ruthenium complex represented by the general formula (1AB), bis(η ⁵ -cyclopentadienyl)ruthenium, bis(η ⁵ -methylcyclopentadienyl)ruthenium, bis(η 5 -ethylcyclopentadienyl), and bis(η ⁵ -methylcyclopentadienyl)ruthenium. dienyl)ruthenium, bis(η ⁵ -propylcyclopentadienyl)ruthenium, bis(η ⁵ -isopropylcyclopentadienyl)ruthenium, bis(η ⁵ -butylcyclopentadienyl)ruthenium, bis(η ⁵ -( sec-butyl)cyclopentadienyl)ruthenium, bis(η ⁵ -isobutylcyclopentadienyl)ruthenium, bis(η ⁵ -(tert-butyl)cyclopentadienyl)ruthenium, bis(η ⁵ -pentylcyclopentadienyl) enyl)ruthenium, bis(η ⁵ -(cyclopentyl)cyclopentadienyl)ruthenium, bis(η ⁵ -hexylcyclopentadienyl)ruthenium, bis(η ⁵ -pentadienyl)ruthenium, bis(η ⁵ -2,4- dimethylpentadienyl)ruthenium, bis(η ⁵ -2,4-diethylpentadienyl)ruthenium, bis(η 5 -2,4-dipropylpentadienyl)ruthenium, bis(η ⁵ -2,4-dimethylpentadienyl)ruthenium, bis(η ⁵ -2,4-dipropylpentadienyl)ruthenium, (isopropyl)pentadienyl)ruthenium, bis(η ⁵ -2,4-dibutylpentadienyl)ruthenium, bis(η ⁵ -2,4-di(isobutyl)pentadienyl)ruthenium, bis(η 5 -2,4-dibutylpentadienyl)ruthenium, bis(η ⁵ -2,4-dibutylpentadienyl)ruthenium, (sec-butyl)pentadienyl)ruthenium, bis(η ⁵ -2,4-di(tert-butyl)pentadienyl)ruthenium, bis(η ⁵ -2,4-dipentylpentadienyl)ruthenium, bis(η ⁵ -2 , 4-dihexylpentadienyl) ruthenium, etc. Among them, ruthenium compounds represented by the general formula (1AB) have suitable vapor pressure and thermal stability as CVD materials and ALD materials. Complexes are preferred. One type or two or more types of these ruthenium compounds can also be used.

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ³ , R ⁴ and Z each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. (Z represents an oxygen atom or CH.)

The definitions of R ¹ and R ² in general formula (1AB) will be explained. The alkyl group having 1 to 6 carbon atoms represented by R ¹ and R ² may be linear, branched or cyclic, and specifically includes a methyl group, ethyl group, propyl group, isopropyl group, cyclo Propyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, pentyl group, 1-ethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, isopentyl group, neopentyl group, tert-pentyl group group, cyclopentyl group, cyclobutylmethyl group, hexyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethyl Butyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, cyclohexyl group, cyclopentylmethyl group, 1-cyclobutylethyl group, 2 -Cyclobutylethyl group, etc. can be exemplified. In that the ruthenium compound has vapor pressure and thermal stability suitable as a CVD material or ALD material, R ¹ and R ² are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ¹ is an ethyl group, It is further preferred that R ² is a hydrogen atom.

The alkyl group having 1 to 6 carbon atoms represented by R ³ and R ⁴ may be linear, branched or cyclic, and specifically includes a methyl group, ethyl group, propyl group, isopropyl group, cyclo Propyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, pentyl group, 1-ethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, isopentyl group, neopentyl group, tert-pentyl group group, cyclopentyl group, cyclobutylmethyl group, hexyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethyl Butyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, cyclohexyl group, cyclopentylmethyl group, 1-cyclobutylethyl group, 2 -Cyclobutylethyl group, etc. can be exemplified. Since the ruthenium compound has vapor pressure and thermal stability suitable for use as a CVD material or an ALD material, R ³ and R ⁴ are preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group.

Specific examples of the ruthenium compound represented by the general formula (1AB) include (η ⁵ -cyclopentadienyl)(η ⁵ -2,4-dimethylpentadienyl)ruthenium, (η ⁵ -2,4-dimethyl pentadienyl)(η ⁵ -methylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl pentadienyl)(η ⁵ -propylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -isopropylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl pentadienyl)(η ⁵ -butylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -isobutylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl pentadienyl)(η ⁵ -sec-butylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -tert-butylcyclopentadienyl)ruthenium, (η ⁵ -cyclopentadienyl) pentadienyl)(η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ - methylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl- 1-oxa-2,4-pentadienyl)(η ⁵ -propylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -isopropylcyclopentadienyl) enyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -butylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa- 2,4-pentadienyl)(η ⁵ -isobutylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -(sec-butyl)cyclopentadienyl) enyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -(tert-butyl)cyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl- 1-oxa-2,4-pentadienyl)(η ⁵ -pentylcyclopentadienyl)ruthenium, (η ⁵ -(cyclopentyl)cyclopentadienyl)(η ⁵ -2,4-dimethyl-1-oxa-2, Examples include ruthenium (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -hexylcyclopentadienyl). All of the exemplified ruthenium compounds can be used for the purpose of producing a ruthenium-containing thin film by the ALD method, and one type or two or more types can also be used, but ruthenium compounds are suitable as CVD materials and ALD materials. In terms of vapor pressure and thermal stability, (η ⁵ -cyclopentadienyl)(η ⁵ -2,4-dimethylpentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -Methylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium, (η ⁵ -cyclopentadienyl)(η ⁵ -2, 4-dimethyl-1-oxa-2,4-pentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -methylcyclopentadienyl)ruthenium, (η ^5-2,4 -dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium is preferred because it has a short film formation delay time and the purity of the obtained film is good. From a certain point, (η ⁵ -2,4-dimethylpentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium, (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)( Particularly preferred is η ⁵ -ethylcyclopentadienyl)ruthenium.

A method for producing a ruthenium-containing thin film using the ruthenium compound of the present invention as a raw material is a method for producing a ruthenium-containing thin film using a ruthenium compound as a raw material by a CVD method or an ALD method, in which the ruthenium compound is chemically reacted. By using a ruthenium compound and one or more types of reducing gas when depositing a ruthenium-containing thin film using a raw material for a vapor phase deposition method based on the method, a ruthenium-containing thin film can be produced in a region-selective manner.

The manufacturing method will be explained in detail below.

In the production method of the present invention, before forming the ruthenium compound into a film by CVD or ALD, pretreatment can be performed to further enhance the region selectivity, and the pretreatment method includes reducing gas It is preferable to introduce the substance into the chamber in advance.

Any reducing gas may be used for the pretreatment, such as ammonia, hydrogen, carbon monoxide, monosilane, hydrazine, monomethylhydrazine, borane-dimethylamine complex, borane-trimethylamine complex, etc. Amine complex, 1-butene, 2-butene, 2-methylpropene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 1- Hexene, 2-hexene, 3-hexene, 2-methyl-1-pentene, 2-methyl-2-pentene, 4-methyl-2-pentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 3-methyl-2-pentene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2,3-dimethyl-2-butene, 3,3-dimethyl-1-butene, but-1, 3-diene, penta-1,3-diene, penta-1,4-diene, 2-methylbuta-1,3-diene, hexa-1,3-diene, hexa-2,4-diene, 2-methylpenta-diene 1,3-diene, 3-methylpenta-1,3-diene, 4-methylpenta-1,3-diene, 2-ethylbuta-1,3-diene, 3-methylpenta-1,4-diene, 2,3-diene Chain unsaturated hydrocarbons such as dimethylbuta-1,3-diene, cyclohexa-1,3-diene, cyclohexa-1,4-diene, 1-methylcyclohexa-1,3-diene, 2-methylcyclohexa -1,3-diene, 5-methylcyclohexa-1,3-diene, 3-methylcyclohexa-1,4-diene, α-phellandrene, β-phellandrene, α-terpinene, β-terpinene, γ - Cyclic unsaturated hydrocarbons such as terpinene and limonene can be exemplified, and one type or two or more types of these can be used. Among them, it is preferable to use ammonia, hydrogen, and formic acid because they are less restricted by the specifications of the film forming apparatus and are easier to handle.

Further, when pre-processing the substrate by introducing a reducing gas into the chamber, it is preferable to heat the substrate to an arbitrary temperature, and the heating temperature is preferably 200°C or higher, and preferably 300°C or higher. is even more preferable.

The substrate used for film formation may have a surface made of a metal film, metal carbide film, metal oxide film, metal nitride film, metal silicide, metal oxycarbide film, metal oxynitride film, glass, resin, silicone resin, or any of these. Composite materials etc. can be used optionally. Specific examples of the metals include gold, silver, copper, platinum, cobalt, ruthenium, silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, Examples include molybdenum and alloys thereof. Among these substrates, substrates whose surfaces are made of a metal oxide film or a metal nitride film, particularly silicon oxide (SiO ₂ ), a composite metal oxide film, tantalum nitride, and titanium nitride, are preferable.

In the film formation of the present invention, a ruthenium-containing thin film is formed selectively in a region, and a substrate on which a ruthenium-containing thin film is easily formed is called a first region, and a substrate on which a ruthenium-containing thin film is difficult to be formed is called a second region. For the substrate in the first region where a ruthenium-containing thin film is likely to be formed, any material can be selected depending on the ruthenium compound used for film formation and the type and flow rate of one or more reducing gases, but examples include ruthenium, cobalt, platinum, tungsten, etc. , metal films such as titanium, tantalum, copper, etc. can be used.

On the other hand, for the second region where a ruthenium-containing thin film is difficult to form, any material can be selected depending on the ruthenium compound used for film formation, the type and flow rate of one or more reducing gases, and examples include metal oxide film, metal nitride film, etc. A film, glass, resin, silicone resin, etc. can be used.

Next, the process of manufacturing a film using the CVD method or the ALD method will be described below.

The vapor phase deposition method based on a chemical reaction in the present invention means a method of producing a metal-containing thin film by decomposing a vaporized metal-containing complex on a substrate. Specifically, CVD methods such as thermal CVD method, plasma CVD method, and optical CVD method, ALD method, etc. can be exemplified. The CVD method is particularly preferred because of its good film formation rate, and the ALD method is particularly preferred because it provides good step coverage. For example, when producing a metal-containing thin film by CVD or ALD, a metal-containing complex is vaporized and supplied to a reaction chamber, and the metal is decomposed on a substrate installed in the reaction chamber. Thin films can be produced. Methods for decomposing metal-containing complexes include the usual technical means used by those skilled in the art to produce metal-containing thin films. Specifically, examples include a method in which a metal-containing complex is reacted with a reactive gas, and a method in which heat, plasma, light, etc. are applied to a metal-containing complex.

When producing a metal-containing thin film by the CVD method or the ALD method, the metal-containing thin film can be produced by appropriately selecting and using these decomposition methods. It is also possible to use a combination of multiple decomposition methods. Methods for supplying the metal-containing complex to the reaction chamber include, for example, methods commonly used by those skilled in the art, such as bubbling and liquid vaporization supply systems, and are not particularly limited.

As the carrier gas, diluent gas, and purge gas when producing a metal-containing thin film by the CVD method or the ALD method, rare gases such as helium, neon, argon, krypton, and xenon, or nitrogen gas are preferable, and nitrogen gas is used for economical reasons. Or argon is more preferred. The flow rates of the carrier gas and diluent gas are adjusted as appropriate depending on the capacity of the reaction chamber. For example, when the capacity of the reaction chamber is 1 to 10 L, the flow rate of the carrier gas is not particularly limited, and is preferably 1 to 10,000 sccm, particularly 1 to 100 sccm, since this enables highly area-selective film formation.

The substrate temperature when producing a metal-containing thin film by the CVD method or the ALD method is less than 1000° C., and is appropriately selected depending on whether heat, plasma, light, etc. are used, the type of reaction gas, etc. For example, when ammonia, hydrogen, cyclic unsaturated hydrocarbon, or the like is used as a reactive gas without using light or plasma, there is no particular restriction on the substrate temperature, and for economical reasons, 100° C. to 600° C. is preferable. The temperature is preferably 200° C. to 400° C. in terms of a good film formation rate. Further, by appropriately using light, plasma, ozone, hydrogen peroxide, etc., a metal-containing thin film can be produced in a temperature range of 300° C. or lower.

Specific examples of reducing gases when producing metal-containing thin films by CVD or ALD include ammonia, hydrogen, carbon monoxide, monosilane, hydrazine, monomethylhydrazine, borane-dimethylamine complex, borane-trimethylamine complex, etc. Borane-amine complex, 1-butene, 2-butene, 2-methylpropene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 1-hexene, 2-hexene, 3-hexene, 2-methyl-1-pentene, 2-methyl-2-pentene, 4-methyl-2-pentene, 4-methyl-1-pentene, 3-methyl-1- Pentene, 3-methyl-2-pentene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2,3-dimethyl-2-butene, 3,3-dimethyl-1-butene, but- 1,3-diene, penta-1,3-diene, penta-1,4-diene, 2-methylbuta-1,3-diene, hexa-1,3-diene, hexa-2,4-diene, 2- Methylpenta-1,3-diene, 3-methylpenta-1,3-diene, 4-methylpenta-1,3-diene, 2-ethylbuta-1,3-diene, 3-methylpenta-1,4-diene, 2, Chain unsaturated hydrocarbons such as 3-dimethylbuta-1,3-diene, cyclohexa-1,3-diene, cyclohexa-1,4-diene, 1-methylcyclohexa-1,3-diene, 2-methyl Cyclohexa-1,3-diene, 5-methylcyclohexa-1,3-diene, 3-methylcyclohexa-1,4-diene, α-phellandrene, β-phellandrene, α-terpinene, β-terpinene Examples include cyclic unsaturated hydrocarbons such as , γ-terpinene, and limonene, and one type or two or more types of these can be used. Among them, it is preferable to use ammonia, hydrogen, and formic acid because they are less restricted by the specifications of the film forming apparatus and are easier to handle.

The flow rate of the reducing gas is adjusted as appropriate depending on the reactivity of the material and the capacity of the reaction chamber. For example, when the capacity of the reaction chamber is 1 to 10 L, the total flow rate of the reducing gas is not particularly limited, and for economic reasons it is preferably 1 to 10,000 sccm, more preferably 1 to 1,000 sccm, and particularly preferably 1 to 500 sccm.

Note that in this specification, sccm is a unit expressing the flow rate of gas, and 1 sccm indicates that gas is moving at a speed of 2.68 mmol/h when converted to ideal gas.

The set for manufacturing a region-selective ruthenium-containing thin film containing a ruthenium compound and one or more types of reducing gas of the present invention is a ruthenium-containing thin film produced region-selectively by CVD or ALD using a ruthenium compound as a raw material. By appropriately selecting other precursors, reducing gases, combinations of a plurality of reducing gases, and manufacturing conditions, a desired type of thin film such as a metal film or an oxide film can be formed. Examples of the composition of the manufactured thin film include a metal ruthenium thin film, a ruthenium oxide thin film, a ruthenium alloy, and a ruthenium-containing composite oxide thin film. Examples of the ruthenium alloy include Pt-Ru alloy. Examples of the ruthenium-containing composite oxide thin film include SrRuO ₃ . These thin films are widely used in the production of, for example, electrode materials for memory devices such as MRAM devices and DRAM devices, resistive films, diamagnetic films used in the recording layer of hard disks, and catalyst materials for polymer electrolyte fuel cells. It is used.

Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. The ruthenium compounds described in Examples 1 to 6 and Comparative Examples 1 and 2 were synthesized according to the method described in International Publication WO2014/088108.

Example 1
Using (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium as the material and ammonia as the reducing gas, region-selectively, A ruthenium-containing thin film was produced by a thermal CVD method. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 69°C, carrier gas flow rate: 20 sccm, ammonia flow rate: 100 sccm, diluent gas flow rate: 80 sccm, substrate temperature: 380°C, reaction chamber total pressure: 1.3 kPa, film formation time 60 minutes. Argon was used as carrier gas and diluent gas.

For region-selective production of a ruthenium-containing thin film, a substrate with a cobalt surface as the first region and a substrate with a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 11 nm in the first region and 0 nm in the second region. was confirmed to be generated.

Example 2
Using (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium as the material and ammonia as the reducing gas, region-selectively, A ruthenium-containing thin film was produced by a thermal CVD method. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 50°C, carrier gas flow rate: 30 sccm, ammonia flow rate: 100 sccm, diluent gas flow rate: 70 sccm, substrate temperature: 400°C, reaction chamber total pressure: 1.3 kPa, film formation time 30 minutes. Argon was used as carrier gas and diluent gas.

In order to fabricate a ruthenium-containing thin film in a region-selective manner, a substrate having a ruthenium surface as the first region and a substrate having a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 15 nm in the first region and 0 nm in the second region. was confirmed to be generated.

Example 3
Using (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium as the material and ammonia as the reducing gas, region-selectively, A ruthenium-containing thin film was produced by a thermal CVD method. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 69°C, carrier gas flow rate: 20 sccm, ammonia flow rate: 40 sccm, diluent gas flow rate: 140 sccm, substrate temperature: 400°C, reaction chamber total pressure: 1.3 kPa, film formation time 60 minutes. Argon was used as carrier gas and diluent gas.

For region-selective production of a ruthenium-containing thin film, a substrate with a cobalt surface as the first region and a substrate with a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 35 nm in the first region and 0 nm in the second region. was confirmed to be generated.

Example 4
(η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium is used as the material, and ammonia and hydrogen are used as reducing gases to achieve a region-selective method. Next, a ruthenium-containing thin film was fabricated by thermal CVD. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 55°C, carrier gas flow rate: 10 sccm, ammonia flow rate: 70 sccm, hydrogen gas flow rate: 30 sccm, diluent gas flow rate: 90 sccm, substrate temperature: 400°C, reaction chamber total pressure: 1.3 kPa, film formation time 30 minutes. . Argon was used as carrier gas and diluent gas.

For region-selective production of a ruthenium-containing thin film, a substrate with a cobalt surface as the first region and a substrate with a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 22 nm in the first region and 1 nm in the second region. was confirmed to be generated.

Example 5
(η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium is used as the material, and ammonia and hydrogen are used as reducing gases to achieve a region-selective method. Next, a ruthenium-containing thin film was fabricated by thermal CVD. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 55°C, carrier gas flow rate: 10 sccm, ammonia flow rate: 50 sccm, hydrogen gas flow rate: 50 sccm, diluent gas flow rate: 90 sccm, substrate temperature: 400°C, reaction chamber total pressure: 1.3 kPa, film formation time 30 minutes. . Argon was used as carrier gas and diluent gas.

In order to fabricate a ruthenium-containing thin film in a region-selective manner, a substrate having a ruthenium surface as the first region and a substrate having a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 21 nm in the first region and 0 nm in the second region. was confirmed to be generated.

Example 6
(η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium is used as the material, and ammonia and hydrogen are used as reducing gases to achieve a region-selective method. Next, a ruthenium-containing thin film was fabricated by thermal CVD. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 55°C, carrier gas flow rate: 10 sccm, ammonia flow rate: 140 sccm, hydrogen gas flow rate: 60 sccm, diluent gas flow rate: 90 sccm, substrate temperature: 400°C, reaction chamber total pressure: 1.3 kPa, film formation time 30 minutes. . Argon was used as carrier gas and diluent gas.

For region-selective production of a ruthenium-containing thin film, a substrate with a cobalt surface as the first region and a substrate with a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 12 nm in the first region and 0 nm in the second region. was confirmed to be generated.

Comparative example 1
Using (η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)ruthenium as a material, a ruthenium-containing thin film was formed using oxygen, an oxidizing gas. It was produced by thermal CVD method. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 69°C, carrier gas flow rate: 20 sccm, oxygen flow rate: 1 sccm, diluent gas flow rate: 179 sccm, substrate temperature: 300°C, reaction chamber total pressure: 1.3 kPa, film formation time 30 minutes. Argon was used as carrier gas and diluent gas.

For region-selective production of a ruthenium-containing thin film, a substrate with a cobalt surface as the first region and a substrate with a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 25 nm in the first region and 25 nm in the second region, and it was found that the film thickness was 25 nm in the first region and 25 nm in the second region. In this embodiment using , it was confirmed that no film was formed in a region-selective manner.

Comparative example 2
(η ⁵ -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η ⁵ -ethylcyclopentadienyl)Ruthenium is used as a material, and ammonia, which is a reducing gas, and oxygen, which is an oxidizing gas, are used as materials. A ruthenium-containing thin film was fabricated using the thermal CVD method. FIG. 1 shows a schematic diagram of the apparatus used to prepare the thin film. The thin film production conditions are as follows.

Material container temperature: 90°C, carrier gas flow rate: 10 sccm, NH3 flow rate: 140 sccm, oxygen flow rate: 1 sccm, diluent gas flow rate: 50 sccm, substrate temperature: 300°C, reaction chamber total pressure: 0.3 kPa, film formation time 30 minutes. Argon was used as carrier gas and diluent gas.

In order to fabricate a ruthenium-containing thin film in a region-selective manner, a substrate having a ruthenium surface as the first region and a substrate having a silicon oxide film surface as the second region were used.

When the produced thin film was measured by fluorescent X-ray analysis, the film thickness calculated from the intensity of characteristic X-rays based on the detected ruthenium was 10 nm in the first region and 8 nm in the second region, indicating that reducing gas and oxidizing gas In this embodiment in which both gases were used as reaction gases, it was confirmed that no film was formed in a region-selective manner.

In the production methods of Examples 1 to 6, in which one or more types of reducing gases are used, the ruthenium-containing thin film can be clearly produced region-selectively in the first region and the second region, whereas only the oxidizing gas In Comparative Example 1 using a reducing gas and Comparative Example 2 using a combination of a reducing gas and an oxidizing gas, a film was formed in both the first region and the second region, and it can be said that a region-selective ruthenium-containing thin film could not be produced. .

1 Material container 2 Constant temperature bath 3 Reaction chamber 4 Substrate 5 Reaction gas inlet 6 Dilution gas inlet 7 Carrier gas inlet 8 Mass flow controller 9 Mass flow controller 10 Mass flow controller 11 Oil rotary pump 12 Exhaust 13 Load lock chamber

Claims (7)

A method for manufacturing a ruthenium-containing thin film by a CVD method or an ALD method using a ruthenium compound as a raw material, the method comprising region-selectively manufacturing a ruthenium-containing thin film using a ruthenium compound and one or more types of reducing gas. A method for producing a ruthenium-containing thin film, characterized by: The ruthenium compound has the general formula (1AB)
(In the formula, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ³ , R ⁴ and Z each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The method for producing a ruthenium-containing thin film according to claim 1, wherein Z represents an oxygen atom or CH. The method for producing a ruthenium-containing thin film according to claim 2, wherein R ¹ and R ² are alkyl groups having 1 to 4 carbon atoms, R ³ and R ⁴ are methyl groups, and Z is an oxygen atom or CH. The method for producing a ruthenium-containing thin film according to claim 2, wherein R ¹ is an ethyl group, R ² is a hydrogen atom, R ³ and R ⁴ are methyl groups, and Z is an oxygen atom or CH. The method for producing a ruthenium-containing film according to any one of claims 1 to 4, wherein ammonia gas is used as the reducing gas. The method for producing a ruthenium-containing thin film according to any one of claims 1 to 4, wherein both ammonia gas and hydrogen gas are used as the reducing gas. A set for producing a region-selective ruthenium-containing thin film, comprising a ruthenium compound and one or more types of reducing gas.