METAL-CONTAINING THIN FILM PRODUCTION METHOD AND METAL-CONTAINING THIN FILM

Abstract

A method for producing a metal-containing thin film having excellent surface smoothness by means of a CVD method or an ALD method; a metal-containing thin film having excellent surface smoothness produced by this method; a method for producing a highly pure metal-containing thin film; and a highly pure metal-containing thin film produced by this method.　The present invention provides a method for producing a metal-containing thin film, said method being characterized by: using a metal complex as a starting material; and forming a film by means of a CVD method or an ALD method after subjecting a substrate to a pretreatment that is capable of inducing adsorption / nucleation of the metal complex. The present invention also provides a method for producing a metal-containing thin film by means of a CVD method or an ALD method using a metal complex as a starting material, said method being characterized by using an oxidizing gas and a reducing gas in combination.

Description

[Technical Field]

[0001] The present invention relates to a method for producing a metal-containing thin film by a CVD method or an ALD method, using a metal complex useful for manufacturing semiconductor devices as a raw material and carrying out a pretreatment that can induce adsorption and nucleation of the complex onto a substrate, and then producing a high-purity ruthenium-containing thin film by a CVD method or an ALD method, using an oxidizing gas and a reducing gas in combination to form the film, as well as a metal-containing thin film and a high-purity ruthenium-containing thin film with excellent surface smoothness obtained by these manufacturing methods. [Background technology]

[0002] Ruthenium has attracted attention as a material for memory electrodes, gate electrodes, copper wiring seed layers, and adhesion layers for DRAMs and other devices due to its high conductivity, ability to form conductive oxides, high work function, excellent etching properties, and excellent lattice matching with copper. Next-generation semiconductor devices employ highly miniaturized and three-dimensional designs to further improve memory capacity and responsiveness. Therefore, in order to use ruthenium as a material for next-generation semiconductor devices, it is necessary to establish a technology for uniformly forming ruthenium-containing thin films with thicknesses of several nanometers to several tens of nanometers on three-dimensional substrates. Chemical reaction-based vapor deposition methods, such as atomic layer deposition (ALD) and chemical vapor deposition (CVD), are considered promising technologies for producing ruthenium-containing thin films on three-dimensional substrates.

[0003] In semiconductor device manufacturing, materials that have suitable vaporization characteristics and thermal stability and can be vaporized at a stable rate are selected to form thin films using CVD or ALD. Another necessary condition is the ability to form thin films with uniform thickness on surfaces with complex three-dimensional structures. Furthermore, to vaporize at a stable rate, it is preferable for the materials to be liquid when they are supplied.

[0004] As a raw material for forming a ruthenium-containing thin film by the CVD method or the ALD method, (η 5 -2,4-dimethylpentadienyl)(η 5 The use of divalent ruthenium compounds such as bis(ethylcyclopentadienyl)ruthenium and bis(ethylcyclopentadienyl)ruthenium has been explored. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 6-283438 [Patent Document 2] Japanese Patent Publication No. 2000-212744 [Patent Document 3] Japanese Patent Publication No. 11-35589 Summary of the Invention [Problem to be solved by the invention]

[0006] Techniques for forming ruthenium-containing thin films by CVD or ALD using several ruthenium compounds as raw materials have been reported (Patent Documents 1 to 3). However, ruthenium compounds generally have a slow initial nucleation rate and a fast growth rate for the generated nuclei, so that the small number of nuclei generated tend to grow into crystals, forming discontinuous films or films with poor surface smoothness. In order to uniformly form ultrathin ruthenium-containing thin films on a substrate, with a thickness of several nanometers to several tens of nanometers, there is a demand for a manufacturing method for forming ruthenium-containing thin films with higher surface smoothness and continuity, and for ruthenium-containing films with higher surface smoothness and continuity. There have been no reports of high-purity ruthenium-containing thin films being obtained from the films obtained in Patent Documents 1 to 3. That is, there is a need for a manufacturing technique for forming a high-purity ruthenium-containing thin film using a liquid ruthenium compound that can be used in a CVD method or an ALD method, and for a high-purity ruthenium-containing thin film. [Means for solving the problem]

[0007] In view of the current situation described above, the inventors have conducted extensive research and have come to provide a method for producing a metal-containing thin film with excellent surface smoothness by using a metal complex as a raw material, subjecting a substrate to a specific pretreatment, and then depositing the film by a CVD method or an ALD method (production method A); a method for producing a high-purity metal-containing thin film by using a metal complex as a raw material and depositing the film by a CVD method or an ALD method under special reaction conditions (production method B); and a method for producing a metal-containing thin film by combining production methods A and B, as well as metal-containing thin films obtained by these production methods. [Effects of the Invention]

[0008] The manufacturing method of the present invention makes it possible to obtain a metal-containing thin film having excellent surface smoothness and a high-purity metal-containing thin film. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an ALD apparatus used in Examples 1 to 9, Comparative Examples 1 to 3, and Reference Example 1.

[0010] The present invention will be described in further detail below. First, the metal complexes used as raw materials in Production Methods A and B will be described. Examples of metal complexes include ruthenium compounds, iridium complexes such as (ethylcyclopentadienyl)(1,3-cyclohexadiene)iridium, (methylcyclopentadienyl)(1,3-cyclohexadiene)iridium, and (ethylcyclopentadienyl)(2,3-dimethyl-1,3-butadiene)iridium, ethene-1,2-diylbis(isopropylamido)bis(tert-pentyloxo)titanium, ethene-1,2-diylbis(tert-butylamido)diethoxotitanium, and ethene-1,2-diylbis( tert-butylamido)diisopropoxotitanium, ethene-1,2-diylbis(tert-butylamido)bis(tert-pentyloxo)titanium, ethene-1,2-diylbis(tert-butylamido)bis(1,1-diethylpropyloxo)titanium, ethene-1,2-diylbis(tert-butylamido)bis(1,1-diethyl-2-methylpropyloxo)titanium, ethene-1,2-diylbis(tert-butylamido)bis(2,2,2-trifluoroethoxo)titanium, ethene-1,2-di titanium complexes such as ethene-1,2-diylbis(tert-pentylamido)dimethoxotitanium, ethene-1,2-diylbis(tert-pentylamido)diethoxotitanium, ethene-1,2-diylbis(tert-pentylamido)diisopropoxotitanium, ethene-1,2-diylbis(tert-pentylamido)di(tert-butoxo)titanium, and ethene-1,2-diylbis(1,1,3,3-tetramethylbutyramido)diisopropoxotitanium; (tert-butylimido)tri(tert-butoxo)niobium; (1,1,3,)tri(tert-butoxo)niobium, (isopropylimido)tri(tert-butoxo)niobium, (methylimido)tri(tert-butoxo)niobium, (ethylimido)tri(tert-butoxo)niobium, (ethylimido)tri(tert-pentyloxo)niobium, (ethylimido)tri(1-ethyl-1-methylpropyloxo)niobium, (tert-butylimido)tri(tert-pentyloxo)niobium, (tert-pentylimido)tri(tert-butoxo)niobium, (1,1,3,)3-tetramethylbutylimido)tri(tert-butoxo)niobium, (methylimido)tris(1-ethyl-1-methylpropyloxo)niobium, (ethylimido)tris(1,1-diethylpropyloxo)niobium, (isopropylimido)tris(1-ethyl-1-methylpropyloxo)niobium, (tert-butylimido)tris(1,1-diethylpropyloxo)niobium, (1,3-dimethylbutylimido)tris(tert-butoxo)niobium, (tert-butylimido)tris(1-methyl-1-propyl Niobium complexes such as (sec-butylimido)tri(tert-butoxo)niobium, (sec-butylimido)tri(tert-butoxo)niobium, 1,1,3,3-tetramethylbutylimido)(triisopropoxo)niobium, (tert-butylimido)(triisopropoxo)niobium, (tert-butylimido)(triethoxo)niobium, (tert-pentylimido)(triisopropoxo)niobium, and (tert-pentylimido)(triethoxo)niobium; (ethylimido)tri(tert-pentyloxo)tantalum; and (ethylimido)tri(1-ethyl -1-methylpropyloxo)tantalum, (isopropylimido)tri(tert-butoxo)tantalum, (propylimido)tri(tert-butoxo)tantalum, (tert-butylimido)tri(tert-butoxo)tantalum, (tert-butylimido)tri(tert-pentyloxo)tantalum, (tert-butylimido)tris(1,1-diethylpropyloxo)tantalum, (tert-pentylimido)tri(tert-butoxo)tantalum, (1,1,3,3-tetramethylbutylimido)tri(t Tantalum complexes such as (tert-butoxo)tantalum, (methylimido)tris(1,1-diethylpropyloxo)tantalum, (ethylimido)tris(1,1-diethylpropyloxo)tantalum, (isopropylimido)tris(1,1-diethylpropyloxo)tantalum, (tert-butylimido)tris(1-ethyl-1-methylpropyloxo)tantalum, (tert-butylimido)tris(1-methyl-1-propylbutyloxo)tantalum, and (sec-butylimido)tri(tert-butoxo)tantalum, (η 5 -acetylcyclopentadienyl)(η4 -buta-1,3-diene)cobalt, (η 5 -acetylcyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -acetylcyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -acetylcyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 4 -buta-1,3-diene)(η 5 -propionylcyclopentadienyl)cobalt, [(1-4-η)-penta-1,3-diene](η 5 -propionylcyclopentadienyl)cobalt, (η 4 -2-methylbuta-1,3-diene)(η 5 -propionylcyclopentadienyl)cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)(η 5 -propionylcyclopentadienyl)cobalt, (η 4 -buta-1,3-diene)(η 5 -butyrylcyclopentadienyl)cobalt, (η 5 -butyrylcyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -butyrylcyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -butyrylcyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 4 -buta-1,3-diene)(η 5 -isobutyrylcyclopentadienyl)cobalt, (η 5 -isobutyrylcyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -isobutyrylcyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)(η 5-isobutyrylcyclopentadienyl)cobalt, (η 4 -buta-1,3-diene)(η 5 -valerylcyclopentadienyl)cobalt, [(1-4-η)-penta-1,3-diene](η 5 -valerylcyclopentadienyl)cobalt, (η 4 -2-methylbuta-1,3-diene)(η 5 -valerylcyclopentadienyl)cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)(η 5 -valerylcyclopentadienyl)cobalt, (η 4 -buta-1,3-diene)(η 5 -isovalerylcyclopentadienyl)cobalt, (η 5 -isovalerylcyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 4 -2-methylbuta-1,3-diene)(η 5 -isovalerylcyclopentadienyl)cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)(η 5 -isovalerylcyclopentadienyl)cobalt, (η 4 -buta-1,3-diene)[η 5 -(3-methylbutanoyl)cyclopentadienyl]cobalt, [η 5 -(3-methylbutanoyl)cyclopentadienyl][(1-4-η)-penta-1,3-diene]cobalt, (η 4 -2-methylbuta-1,3-diene)[η 5 -(3-methylbutanoyl)cyclopentadienyl]cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)[η 5 -(3-methylbutanoyl)cyclopentadienyl]cobalt, (η 4 -buta-1,3-diene)(η 5 -pivaloylcyclopentadienyl)cobalt, [(1-4-η)-penta-1,3-diene](η 5 -pivaloylcyclopentadienyl)cobalt, (η 4 -2-methylbuta-1,3-diene)(η5 -pivaloylcyclopentadienyl)cobalt, (η 4 -2,3-dimethylbuta-1,3-diene)(η 5 -pivaloylcyclopentadienyl)cobalt, (η 5 -formylcyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -formylcyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -formylcyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -formylcyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -(fluoroacetyl)cyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -(fluoroacetyl)cyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -(fluoroacetyl)cyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -(fluoroacetyl)cyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -(difluoroacetyl)cyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -(difluoroacetyl)cyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -(difluoroacetyl)cyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -(difluoroacetyl)cyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -(trifluoroacetyl)cyclopentadienyl)(η 4-buta-1,3-diene)cobalt, (η 5 -(trifluoroacetyl)cyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -(trifluoroacetyl)cyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -(trifluoroacetyl)cyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -(pentafluoropropionyl)cyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -(pentafluoropropionyl)cyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -(pentafluoropropionyl)cyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -(pentafluoropropionyl)cyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -(heptafluorobutyryl)cyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -(heptafluorobutyryl)cyclopentadienyl)[(1-4-η)-penta-1,3-diene]cobalt, (η 5 -(heptafluorobutyryl)cyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -(heptafluorobutyryl)cyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5-1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -buta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -2-methylbuta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylpenta-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylpenta-1,3-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -2-methylpenta-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -2-methylpenta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4-2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -2,3-dimethylbuta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -penta-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -penta-1,3-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -penta-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -penta-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -cyclohexa-1,3-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -cyclohexa-1,3-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -cyclohexa-1,3-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -cyclohexa-1,3-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -cycloocta-1,5-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η4 -cycloocta-1,5-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -cycloocta-1,5-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 -cycloocta-1,5-diene)cobalt, (η 5 -1-trimethylsilyloxycyclopentadienyl)(η 4 -norborna-2,5-diene)cobalt, (η 5 -3-methyl-1-trimethylsilyloxycyclopentadienyl)(η 4 -norborna-2,5-diene)cobalt, (η 5 -1,3,4,5-tetramethyl-2-trimethylsilyloxycyclopentadienyl)(η 4 -norborna-2,5-diene)cobalt, (η 5 -1-methyl-3,4-bis(trimethylsilyloxy)cyclopentadinyl)(η 4 Among these, ruthenium compounds are preferred. These metal complexes can be used singly or in combination of two or more kinds.

[0011] Ruthenium compounds preferred as metal complexes include, for example, ruthenium complexes represented by the following general formula (1AB), bis(η 5 -cyclopentadienyl)ruthenium, bis(η 5 -methylcyclopentadienyl)ruthenium, bis(η 5 -ethylcyclopentadienyl)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)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-di(isopropyl)pentadienyl)ruthenium, bis(η 5 -2,4-dibutylpentadienyl)ruthenium, bis(η 5 -2,4-di(isobutyl)pentadienyl)ruthenium, bis(η 5 -2,4-di(sec-butyl)pentadienyl)ruthenium, bis(η 5 -2,4-di(tert-butyl)pentadienyl)ruthenium, bis(η 5 -2,4-dipentylpentadienyl)ruthenium, bis(η 5 Among these, ruthenium complexes represented by general formula (1AB) are preferred because the ruthenium compounds have vapor pressure and thermal stability suitable for use as CVD or ALD materials. These ruthenium compounds can be used alone or in combination of two or more.

[0012] [ka] (In the formula, R 1 and R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R 3 and R 4 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Z represents an oxygen atom or CH.

[0013] R in general formula (1AB) 1 and R 2 The definition of R is explained. 1 and R 2 The alkyl group having 1 to 6 carbon atoms represented by the formula (I) may be linear, branched, or cyclic, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a cyclopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclobutyl group, a pentyl group, a 1-ethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, a cyclobutylmethyl group, a hexyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 4-methylpentyl group, a 1,1-dimethylbutyl group, a 1,2-dimethylbutyl group, a 1,3-dimethylbutyl group, a 2,2-dimethylbutyl group, a 2,3-dimethylbutyl group, a 3,3-dimethylbutyl group, a cyclohexyl group, a cyclopentylmethyl group, a 1-cyclobutylethyl group, and a 2-cyclobutylethyl group. Ruthenium compounds have suitable vapor pressure and thermal stability for use as CVD and ALD materials. 1 and R 2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R 1 is an ethyl group, and R 2 It is more preferable that is a hydrogen atom.

[0014] R 3 and R 4The alkyl group having 1 to 6 carbon atoms represented by the formula (I) may be linear, branched, or cyclic, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a cyclopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclobutyl group, a pentyl group, a 1-ethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, a cyclobutylmethyl group, a hexyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 4-methylpentyl group, a 1,1-dimethylbutyl group, a 1,2-dimethylbutyl group, a 1,3-dimethylbutyl group, a 2,2-dimethylbutyl group, a 2,3-dimethylbutyl group, a 3,3-dimethylbutyl group, a cyclohexyl group, a cyclopentylmethyl group, a 1-cyclobutylethyl group, and a 2-cyclobutylethyl group. Ruthenium compounds have suitable vapor pressure and thermal stability for use as CVD and ALD materials. 3 and R 4 is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group.

[0015] 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-dimethylpentadienyl)(η 5 -methylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -ethylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -propylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -isopropylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -butylcyclopentadienyl)ruthenium, (η 5-2,4-dimethylpentadienyl)(η 5 -isobutylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -sec-butylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethylpentadienyl)(η 5 -tert-butylcyclopentadienyl)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, (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)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)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-2,4-pentadienyl)ruthenium and (η 5 -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η 5 Any of the ruthenium compounds exemplified above can be used for the purpose of producing a ruthenium-containing thin film by a CVD method or an ALD method, and one or more types can be used. Among them, ruthenium compounds are preferred in that they have a vapor pressure and thermal stability suitable for use as a CVD material or an ALD material. 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, and (η 5 -2,4-dimethylpentadienyl)(η 5 -ethylcyclopentadienyl)ruthenium, (η 5 -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η 5 -ethylcyclopentadienyl)ruthenium is more preferred.

[0016] First, manufacturing method A will be described. Manufacturing method A uses a metal complex as a raw material, and after subjecting a substrate to a pretreatment that can induce adsorption and nucleation of the metal complex, a film is formed by CVD or ALD to produce a metal-containing thin film with excellent surface smoothness.

[0017] The pretreatment step will be described in detail below. The substrate used may be any substrate having a surface made of a metal film, metal carbide film, metal oxide film, metal nitride film, metal carbide oxide film, metal oxynitride film, glass, resin, silicon resin, or a composite material thereof. Specific examples of the metal include gold, silver, platinum, silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum, or alloys thereof. Among these substrates, substrates having a surface made of a metal oxide film or metal nitride film are particularly preferred, and substrates having a surface made of silicon oxide (SiO), a composite metal oxide film, tantalum nitride, or titanium nitride are particularly preferred. As a pretreatment method capable of inducing adsorption and nucleation of a metal complex on a substrate, any treatment can be used as long as it can improve the amount of adsorption and density of the raw material, and particularly, any of the following methods 1) to 4) is preferred. Note that the following treatment methods may be used alone or in combination.

[0018] 1) A method in which a reducing gas is introduced into a reaction chamber to treat the surface of a substrate before film formation. Any reducing gas may be used, for example, ammonia, hydrogen, carbon monoxide, hydrazine, monomethylhydrazine, etc., as well as hydrocarbon gases such as methane, ethane, ethylene, acetylene, propane, butane, butene, pentane, isobutane, and hexane, and among these, ammonia or hydrogen is preferred. When pretreating the substrate by introducing a reducing gas into the reaction chamber, it is preferable to heat the substrate to a desired temperature, preferably 200°C or higher, more preferably 300°C or higher.

[0019] 2) A method of generating plasma to treat the surface of the substrate before film deposition The environment in which the plasma is generated is arbitrary, and it can be generated in an atmosphere containing the reducing gas, or it can be heated to an arbitrary temperature. The RF power during plasma generation can be set arbitrarily, and is preferably in the range of 1 to 10,000 W, more preferably 1 to 1,000 W, and particularly preferably 20 to 500 W. The RF power refers to the power value of the high frequency wave that excites the plasma.

[0020] 3) A method of performing surface treatment by heating the substrate surface before film deposition The heating temperature when heating the substrate surface before film formation can be any temperature as long as it is a temperature at which surface treatment can be performed, and is preferably the film formation temperature or higher because it can remove impurities such as organic substances attached to the substrate surface. The atmosphere in the reaction chamber during heating may be a closed-circuit atmosphere or an inert gas atmosphere such as argon or nitrogen.

[0021] 4) A method of introducing a metal complex into a reaction chamber before film formation to adsorb the metal complex on the substrate surface, or a method of forming a precursor thin layer on the substrate surface using a decomposition product of the metal complex, or both of these methods are performed.

[0022] The metal complex may be introduced into the reaction chamber by any method, including continuous supply of vaporized metal complexes or alternate pulsation with an inert gas such as argon or nitrogen. The reaction chamber temperature can be set to any temperature, and it is preferable to supply the metal complex at a temperature equal to or higher than the film formation temperature, as this is expected to improve the nucleus density. Furthermore, it is particularly preferable that the reaction chamber temperature be equal to or higher than the thermal decomposition temperature of the metal complex used, as this is expected to result in a metal-containing thin film with higher smoothness.

[0023] Next, the process for producing a film by the CVD method or the ALD method will be described below. Regarding the film formation process using the CVD method or the ALD method, the film formation technique is not particularly limited. Vaporized vapor of the metal complex, along with optional reactive gases, diluent gases, and purge gases, are simultaneously or alternately introduced into a reaction chamber containing a substrate, and the metal complex is decomposed and / or chemically reacted in the vapor phase or on the substrate to grow and deposit a thin film on the substrate surface. Examples of CVD and ALD methods that can be used include chemical vapor deposition (CVD), atomic layer deposition (ALD), molecular layer deposition (MLD), plasma enhanced chemical vapor deposition (PECVD), plasma enhanced atomic layer deposition (PEALD), low-pressure chemical vapor deposition (LPCVD), atmospheric pressure CVD, and pulsed CVD. The CVD method is preferred due to its high film formation rate, and the ALD method is particularly preferred due to its excellent step coverage.

[0024] When a metal-containing thin film is produced on a substrate using a metal complex as a raw material by CVD or ALD, the metal complex is gasified and supplied to the substrate. Gasification methods include, for example, placing the metal complex in a heated thermostatic chamber and blowing in a carrier gas such as helium, neon, argon, krypton, xenon, or nitrogen. Alternatively, the metal complex may be prepared as a solution or as a solution using a solvent, which is then sent to a vaporizer, heated, and gasified. Examples of solvents used to prepare a solution include ethers such as 1,2-dimethoxyethane, diglyme, triglyme, dioxane, tetrahydrofuran, and cyclopentyl methyl ether, and hydrocarbons such as hexane, cyclohexane, methylcyclohexane, ethylcyclohexane, heptane, octane, nonane, decane, benzene, toluene, ethylbenzene, and xylene.

[0025] In the CVD and ALD methods, a metal-containing thin film can be produced by reacting the vapor of the metal complex supplied as a gas onto a substrate with a reactive gas. Decomposition can be achieved by heating alone, or by using plasma or light in combination. Any reactive gas can be used as needed, and examples of such gases include oxidizing gases, hydrocarbon gases, and reducing gases. Specific examples of oxidizing gases include oxygen, ozone, water vapor, hydrogen peroxide, hydrogen chloride, nitric acid gas, acetic acid, acetic anhydride, nitrogen dioxide, nitric oxide, laughing gas, hydrogen chloride, and nitric acid. Specific examples of hydrocarbon gases include methane, ethane, ethylene, acetylene, propane, butane, butene, pentane, isobutane, hexane, and organic amine compounds, including monoalkylamines, dialkylamines, trialkylamines, and alkylenediamines. Specific examples of reducing gases include ammonia, hydrogen, carbon monoxide, monosilane, hydrazine, monomethylhydrazine, borane-amine complexes such as borane-dimethylamine complexes and borane-trimethylamine complexes, 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, buta-1,3-diene, penta-1,3-diene, penta- Chain unsaturated hydrocarbons such as 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, and 2,3-dimethylbuta-1,3-diene; cyclohexa-1,3 Examples of cyclic unsaturated hydrocarbons include cyclohexene, 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-terpinene, and limonene. One or more of these reactive gases can be used. The reactive gases are preferably oxygen, ozone, water vapor, ammonia, hydrogen, formic acid, cyclohexa-1,3-diene, cyclohexa-1,4-diene, α-terpinene, β-terpinene, γ-terpinene, or limonene, because they are less restricted by the specifications of the film-forming apparatus and are easy to handle.

[0026] The flow rate of the reaction gas is adjusted appropriately depending on the reactivity of the material and the volume of the reaction chamber. For example, when the volume of the reaction chamber is 1 to 10 L, the flow rate of the reaction gas is not particularly limited, but for economic reasons, it is preferably 1 to 10,000 sccm, more preferably 1 to 1,000 sccm, and particularly preferably 10 to 500 sccm. In this specification, sccm is a unit of gas flow rate, and 1 sccm represents a gas moving at a rate of 2.68 mmol / h when converted to an ideal gas.

[0027] In the film formation process using the CVD method or the ALD method, the inert gas used as a carrier gas, diluent gas, or purge gas is preferably a rare gas or nitrogen, and from an economical standpoint, nitrogen, helium, neon, or argon is preferred. The flow rate of the inert gas is adjusted appropriately depending on the capacity of the reaction chamber, and 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 from an economical standpoint, it is preferably 1 to 10,000 sccm, more preferably 1 to 1,000 sccm, and particularly preferably 1 to 500 sccm.

[0028] In the production method A, a pretreatment capable of inducing adsorption and nucleation of the metal complex onto the substrate is carried out, and then a film is produced by the CVD method, as follows. After the pretreatment, the metal complex is gasified in the CVD apparatus using the method described above and introduced into the reaction chamber, where a decomposition reaction produces a metal-containing thin film on the substrate. The decomposition reaction may be caused by heat alone, or by the use of a reactive gas, or by the combined use of plasma or light. In addition to the vapor of the metal complex and the reactive gas, an inert gas may also be introduced as a diluent gas. As described above, a rare gas or nitrogen is preferably used as the diluent gas, and nitrogen, helium, neon, or argon are preferred for economic reasons.

[0029] In the CVD method, after the thin film deposition, an annealing treatment may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere to obtain better electrical properties, and a reflow step may be performed if step filling is required. The temperature in the annealing treatment and the reflow step is usually 100 to 1000°C, and preferably 200 to 500°C.

[0030] In Production Method A, a film formation method in which a film is produced by the ALD method after a pretreatment that can induce adsorption and nucleation of a metal complex onto a substrate is performed is described below. After the pretreatment, a thin film deposition cycle is performed by a series of operations consisting of a) a raw material introduction step, b) an evacuation and / or purging step, c) a reactive gas introduction step, and d) an evacuation and / or purging step. This cycle may be repeated multiple times until a thin film of the required thickness is obtained. Furthermore, when forming a metal-containing thin film by the ALD method, energy such as plasma, light, or voltage may be applied. The timing of applying this energy is not particularly limited, and may be during, for example, any of the pretreatment step, raw material introduction step, evacuation and / or purging step, and reactive gas introduction step, which can induce adsorption and nucleation of the metal complex on the substrate, or between the above steps.

[0031] In the ALD method, after the thin film deposition, an annealing treatment may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere to obtain better electrical properties, and a reflow step may be performed if step filling is required. The temperature in the annealing treatment and the reflow step is usually 100 to 1000°C, and preferably 200 to 500°C.

[0032] The reaction temperature (substrate temperature) in the film formation process using the CVD method or ALD method is appropriately selected depending on the use of heat, plasma, light, etc., the type of reactive gas, etc. For example, when oxygen is used as the reactive gas without the use of light or plasma, there are no particular limitations on the substrate temperature, and a temperature of room temperature to 1000°C is preferred because this is a temperature at which the metal complex used in the present invention reacts sufficiently. In terms of the film formation rate, the composition of the resulting film, and surface smoothness, a temperature of 100°C to 800°C is more preferred, and a temperature of 150°C to 400°C is particularly preferred. Furthermore, by appropriately using light, plasma, ozone, hydrogen peroxide, etc., a metal-containing thin film can be produced at a temperature range of 300°C or less.

[0033] In the case of thermal CVD and ALD, the reaction in the film formation process by the CVD method or ALD method is preferably carried out under reduced pressure conditions in order to achieve good film thickness uniformity, step coverage (coating ability), and film quality. The reaction pressure is more preferably 0 to 100 Torr, and particularly preferably 0 to 10 Torr.

[0034] After pretreatment using a metal complex, a film can be produced by CVD or ALD using a well-known chemical vapor deposition (CVD) or atomic layer deposition (ALD) system. Specific examples of the system include an ALD system capable of supplying precursors by bubbling, as shown in Figure 1, as well as a system with a vaporization chamber or a system capable of plasma treatment of reactive gases. Furthermore, the system is not limited to the single-wafer system shown in Figure 1; a system capable of simultaneously processing multiple wafers using a batch furnace can also be used.

[0035] The metal-containing thin film with excellent surface smoothness obtained by Production Method A can be made into a desired type of thin film, such as a metal, oxide ceramic, nitride ceramic, or glass, by appropriately selecting other precursors, reactive gases, and production conditions. Examples of the composition of the produced thin film include metal thin films, metal oxide thin films, metal alloys, and metal-containing complex oxide thin films. Examples of metal alloys include Pt—Ru alloys. Examples of metal-containing complex oxide thin films include SrRuO. These thin films are widely used in the production of electrode materials for memory elements, such as MRAM elements and DRAM elements, resistive films, diamagnetic films used in the recording layers of hard disks, and catalyst materials for polymer electrolyte fuel cells.

[0036] Next, manufacturing method B will be described. Production method B is a method for producing a metal-containing thin film by a CVD method or an ALD method using a metal complex as a raw material, and is characterized by using an oxidizing gas and a reducing gas in combination.

[0037] In the manufacturing method B, it is preferable to perform a pretreatment on the substrate in the manufacturing method A before forming a film by the CVD method or the ALD method, which is capable of inducing adsorption and nucleation of the metal complex. That is, it is preferable to use a metal complex as a raw material, subject the substrate to a pretreatment capable of inducing adsorption and nucleation of the metal complex, and then form a film by CVD or ALD using a combination of an oxidizing gas and a reducing gas. In the manufacturing method B, the same methods as those in the manufacturing method A can be used for the film formation process by the CVD method or the ALD method and the gasification method.

[0038] In production method B, the vapor of the metal complex supplied as a gas onto the substrate is reacted with an oxidizing gas and a reducing gas to decompose the metal complex adsorbed on the substrate, thereby producing a metal-containing thin film. Decomposition can be achieved using only two gases, an oxidizing gas and a reducing gas, and heat, or by using plasma or light in combination. The use of both oxidizing and reducing gases in manufacturing method B makes it possible to manufacture high-purity metal-containing thin films. In general film formation by CVD or ALD methods, either oxidizing or reducing gases are used, but by using them in combination, it is possible to reduce the impurity concentration in the film.

[0039] The oxidizing gas and reducing gas used in film formation will be described in detail below. Specific examples of the oxidizing gas include oxygen, ozone, water vapor, hydrogen peroxide, hydrogen chloride, nitric acid gas, acetic acid, acetic anhydride, nitrogen dioxide, nitric oxide, laughing gas, hydrogen chloride, and nitric acid, and these can be used alone or in combination. Of these, oxygen or ozone is preferred because of its good reactivity with the metal complex raw material, its ease of handling due to fewer restrictions imposed by the specifications of the film-forming apparatus, and its ease of use.

[0040] Specific examples of reducing gases include ammonia, hydrogen, carbon monoxide, monosilane, hydrazine, monomethylhydrazine, borane-amine complexes such as borane-dimethylamine complex and borane-trimethylamine 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, buta-1,3-diene, penta-1,3-diene, penta-1,4-diene, 2- Chain unsaturated hydrocarbons such as 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, and 2,3-dimethylbuta-1,3-diene; cyclohexa-1,3-diene; and cyclohexa-1,4-diene. Examples of cyclic unsaturated hydrocarbons include dienes, 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-terpinene, and limonene, and these can be used alone or in combination. Among these, ammonia, hydrogen, and formic acid are preferred, and ammonia or hydrogen is more preferred, in that they are less restricted by the specifications of the film-forming apparatus and are easy to handle.

[0041] The flow rates of the oxidizing gas and reducing gas are adjusted appropriately depending on the reactivity of the materials and the volume of the reaction chamber. For example, when the volume of the reaction chamber is 1 to 10 L, there are no particular restrictions on the flow rates of the oxidizing gas and reducing gas, but for economic reasons, 1 to 10,000 sccm is preferred, 1 to 1,000 sccm is more preferred, and 10 to 500 sccm is particularly preferred. In this specification, sccm is a unit of gas flow rate, and 1 sccm represents a gas moving at a rate of 2.68 mmol / h when converted to an ideal gas.

[0042] There are no particular restrictions on the ratio of oxidizing gas to reducing gas, and from the viewpoint of reactivity with the raw material gas, the ratio of oxidizing gas to reducing gas is preferably 100:1 to 1:100, more preferably 50:1 to 1:50, and particularly preferably 10:1 to 1:10. In the film formation process, the inert gas used as a carrier gas, dilution gas, or purge gas is preferably a rare gas or nitrogen, and from an economical standpoint, nitrogen, helium, neon, or argon is preferred. The flow rate of the inert gas is appropriately adjusted depending on the volume of the reaction chamber, and for example, when the volume of the reaction chamber is 1 to 10 L, the flow rate of the carrier gas is not particularly limited, and from an economical standpoint, it is preferably 1 to 10,000 sccm, more preferably 1 to 1,000 sccm, and particularly preferably 1 to 500 sccm.

[0043] The film formation method for producing a film in Production Method B is described below. Any method can be used to form a film as long as it uses vapor of the metal complex supplied as a gas onto a substrate, an oxidizing gas, and a reducing gas. In addition to these oxidizing and reducing gases, plasma or light can also be used. One example is a method in which one cycle consists of a series of operations: (a) a raw material introduction step, (b) an evacuation and / or purging step, (c) an oxidizing gas introduction step, (d) an evacuation and / or purging step, (e) a reducing gas introduction step, and (f) an evacuation and / or purging step. By repeating this cycle multiple times, a thin film of the required thickness can be obtained.

[0044] In addition, energy such as plasma, light, or voltage may be applied in forming the metal-containing thin film. The timing of applying such energy is not particularly limited, and may be, for example, during any of the raw material introduction step, exhaust and / or purging step, oxidizing gas introduction step, and reducing gas introduction step, or between the above steps.

[0045] In the manufacturing process, after thin film deposition, annealing may be performed in an inert, oxidizing, or reducing atmosphere to obtain better electrical properties, and a reflow step may be performed if step filling is required. The temperature in the annealing and reflow steps is usually 100 to 1000°C, and preferably 200 to 500°C.

[0046] The reaction temperature (substrate temperature) in the film formation process is appropriately selected depending on whether heat, plasma, light, etc. are used, the types of oxidizing gas and reducing gas, etc. For example, when oxygen is used as the oxidizing gas and ammonia as the reducing gas without using light or plasma, there are no particular limitations on the substrate temperature, and a temperature of room temperature to 1000°C is preferred because this is a temperature at which the metal complex used in the present invention reacts sufficiently. From the viewpoints of film formation rate, the composition of the resulting film, and surface smoothness, a temperature of 100°C to 800°C is preferred, and a temperature of 150°C to 400°C is more preferred. Furthermore, by appropriately using light or plasma, ozone, hydrogen peroxide, etc., a metal-containing thin film can be produced at a temperature range of 300°C or less. The reaction in the film formation step is preferably carried out under reduced pressure conditions in order to obtain good film thickness uniformity, step coverage (coating properties), and film quality, and the reaction pressure is more preferably 0 to 100 Torr, and particularly preferably 0 to 10 Torr.

[0047] As an apparatus for producing a film, a well-known chemical vapor deposition apparatus (CVD apparatus) or atomic layer deposition apparatus (ALD apparatus) can be used. Specific examples of the apparatus include an ALD apparatus capable of supplying precursors by bubbling, as shown in Figure 1, as well as an apparatus having a vaporization chamber or an apparatus capable of plasma treatment of reactive gases. Furthermore, the apparatus is not limited to the single-wafer apparatus shown in Figure 1, and an apparatus capable of simultaneously processing multiple wafers using a batch furnace can also be used.

[0048] The high-purity metal-containing thin film produced by Production Method B can be made into a desired type of thin film, such as a metal, oxide ceramic, nitride ceramic, or glass, by appropriately selecting other precursors, oxidizing gas, reducing gas, and production conditions. Examples of the composition of the produced thin film include metal thin films, metal oxide thin films, metal alloys, and metal-containing complex oxide thin films. Examples of metal alloys include Pt-Ru alloys. Examples of metal-containing complex oxide thin films include SrRuO. These thin films are widely used in the production of electrode materials for memory elements, such as MRAM elements and DRAM elements, resistive films, diamagnetic films used in the recording layers of hard disks, and catalyst materials for polymer electrolyte fuel cells. [Example]

[0049] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The ruthenium compounds described in Examples 1 to 9, Comparative Examples 1 to 3, and Reference Example 1 were synthesized according to the method described in JP-A-2003-342286.

[0050] Example 1 (η 5 -2,4-dimethylpentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Ammonia gas was introduced at 50 sccm into a reaction chamber in which a substrate to be used for film formation was placed, and the substrate was pretreated for 5 minutes while maintaining the substrate temperature at 250° C. and the total pressure in the reaction chamber at 300 Pa. (2)ALD film formation process Purge gas: argon, oxygen as a reactive gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor was vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa. The raw material gas was used as the raw material gas. The substrate temperature was 250°C and the total pressure in the reaction chamber was 300 Pa. One cycle consisted of the following steps (a) to (f), and the cycle was repeated 200 times for a total of 63 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of source gases is stopped and unreacted material is removed by a 5 second argon purge (150 sccm). (d) In addition to (a), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (e) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (f) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. The produced thin film was analyzed by X-ray fluorescence analysis, and characteristic X-rays due to ruthenium were detected. The film thickness was calculated from the intensity of the detected X-rays and was found to be 22 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 2.61.

[0051] Example 2 (η 5 -2,4-dimethylpentadienyl)(η 5Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Ammonia gas was introduced at 50 sccm into a reaction chamber containing a substrate to be used for film formation. The substrate temperature was kept at 250°C, the total pressure of the reaction chamber was kept at 300 Pa, plasma was generated at an RF power of 30 W, and the substrate was pretreated for 5 minutes. (2)ALD film formation process ALD film formation was carried out under the same conditions as in Example (1). The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays and was found to be 25 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 1.63.

[0052] Example 3 (η 5 -2,4-dimethylpentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Ammonia gas was introduced at 50 sccm into a reaction chamber in which a substrate to be used for film formation was placed, and the substrate was pretreated for 10 minutes while maintaining the substrate temperature at 250° C. and the total pressure in the reaction chamber at 1000 Pa. (2)ALD film formation process ALD film formation was carried out under the same conditions as in Example (1). The produced thin film was analyzed by X-ray fluorescence analysis, and characteristic X-rays due to ruthenium were detected. The film thickness was calculated from the intensity of the detected X-rays and was found to be 20 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 1.37.

[0053] Example 4 (η 5 -2,4-dimethylpentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Purge gas: argon, raw material gas, Carrier gas: argon 10sccm, The raw material vapor was vaporized by bubbling under the conditions of a material container temperature of 90° C. and a material vapor pressure of 38.1 Pa, and was used as the raw material gas. Under conditions of a substrate temperature of 500° C. and a total pressure in the reaction chamber of 1000 Pa, one cycle consisting of the following steps (a) and (b) was repeated 100 times for a total of 13 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds. (b) In addition to (a), the source gas is introduced into the reaction chamber for 5 seconds. (2)ALD film formation process Purge gas: argon, oxygen and ammonia as reactive gases, raw material gas The raw material vapor evaporated under the same conditions as in the pretreatment process was used as the raw material gas, and the following steps (a) to (l) were repeated 100 times for a total of 48 minutes under the conditions of a substrate temperature of 250°C and a total pressure in the reaction chamber of 300 Pa. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (e) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (i) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays, and it was found to be 7 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 0.72.

[0054] Example 5 (η 5 -2,4-dimethylpentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Purge gas: argon, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa was used as the raw material gas. Under the conditions of a substrate temperature of 250°C and a reaction chamber total pressure of 1000 Pa, the following steps (a) and (b) were considered as one cycle, and were repeated 100 times for a total of 13 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds. (b) In addition to (a), the source gas is introduced into the reaction chamber for 5 seconds. (2)ALD film formation process ALD film formation was carried out under the same conditions as in Example (4). The produced thin film was analyzed by X-ray fluorescence analysis, and characteristic X-rays due to ruthenium were detected. The film thickness was calculated from the intensity of the detected X-rays and was found to be 3 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 2.04.

[0055] Example 6 Using (2,4-dimethyl-pentadienyl) (ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method. The thin film production conditions are as follows. Purge gas: argon, oxygen as oxidizing gas, ammonia as reducing gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor was vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa. The raw material gas was used as the raw material gas. The substrate temperature was 250°C and the total pressure in the reaction chamber was 300 Pa. One cycle consisted of the following steps (a) to (l), and this was repeated 250 times for a total of 121 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. (e) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa.

[0056] (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (i) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays, and the composition of this ruthenium-containing thin film was analyzed by X-ray photoelectron spectroscopy, which revealed that the ruthenium content was 98 atom%.

[0057] Example 7 Using (2,4-dimethyl-pentadienyl)(ethylcyclopentadienyl)ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment process and (2) the ALD film formation process, are as follows.

[0058] (1) Pretreatment process Purge gas: argon, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa was used as the raw material gas. Under the conditions of a substrate temperature of 500°C and a reaction chamber total pressure of 1000 Pa, the following steps (a) and (b) were considered as one cycle, and were repeated 100 times for a total of 13 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds. (b) In addition to (a), the source gas is introduced into the reaction chamber for 5 seconds. (2)ALD film formation process Purge gas: argon, oxygen as oxidizing gas, ammonia as reducing gas, raw material gas, The raw material vapor evaporated under the same conditions as in the pretreatment process was used as the raw material gas, and the following steps (a) to (l) were repeated 300 times for a total of 145 minutes under the conditions of a substrate temperature of 250°C and a total pressure in the reaction chamber of 300 Pa. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. (e) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa.

[0059] (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. (i) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays, and the composition of this ruthenium-containing thin film was analyzed by X-ray photoelectron spectroscopy, which revealed that the ruthenium content was 97 atom%.

[0060] Example 8 (η 5 -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows. (1) Pretreatment process Purge gas: argon, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of material container temperature: 90°C, material vapor pressure: 35.7 Pa is used as the raw material gas, and is introduced into the reaction chamber for 30 minutes under the conditions of substrate temperature: 400°C, and reaction chamber total pressure: 300 Pa.

[0061] (2)ALD film formation process Purge gas: argon, oxygen as oxidizing gas, ammonia as reducing gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 35.7 Pa was used as the raw material gas, and the following steps (a) to (l) were considered as one cycle and were repeated 150 times for a total of 72.5 minutes under the conditions of a substrate temperature of 250°C and a reaction chamber total pressure of 300 Pa. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (e) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa.

[0062] (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (i) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays to be 7 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root-mean-square roughness (RMS) was 1.02. Furthermore, analysis of the composition of this ruthenium-containing thin film by X-ray photoelectron spectroscopy revealed that the ruthenium content was 94 atom%.

[0063] Example 9 (η 5 -2,4-dimethyl-1-oxa-2,4-pentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a Pt substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment step and (2) the ALD film formation step, are as follows.

[0064] (1) Pretreatment process The raw material vapor was vaporized by bubbling with purge gas: argon, raw material gas: carrier gas: argon 10 sccm, material container temperature: 90°C, material vapor pressure: 35.7 Pa, and introduced into the reaction chamber for 30 minutes under the following conditions: substrate temperature: 400°C, reaction chamber total pressure: 300 Pa.

[0065] (2)ALD film formation process Purge gas: argon, oxygen as oxidizing gas, ammonia as reducing gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 35.7 Pa was used as the raw material gas, and the following steps (a) to (l) were considered as one cycle and were repeated 150 times for a total of 72.5 minutes under the conditions of a substrate temperature of 250°C and a reaction chamber total pressure of 300 Pa. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. (e) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa.

[0066] (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. (i) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of argon as a purge gas is introduced into the reaction chamber for 1 second, and the pressure in the reaction chamber is increased. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays to be 7 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root-mean-square roughness (RMS) was 1.28. Furthermore, analysis of the composition of this ruthenium-containing thin film by X-ray photoelectron spectroscopy revealed that the ruthenium content was 98 atom%.

[0067] Comparative Example 1 (η 5 -2,4-dimethylpentadienyl)(η 5Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method. The thin film production conditions are as follows. Purge gas: argon, oxygen as a reactive gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor was vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa. The raw material vapor was used as the raw material gas. The substrate temperature was 250°C and the total pressure in the reaction chamber was 300 Pa. One cycle consisted of the following steps (a) to (f), and this was repeated 200 times for a total of 63 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of source gases is stopped and unreacted material is removed by a 5 second argon purge (150 sccm).

[0068] (d) In addition to (a), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (e) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (f) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays and was found to be 29 nm. Furthermore, AFM observation of this ruthenium-containing thin film revealed that the root mean square roughness (RMS) was 3.34.

[0069] Comparative Example 2 (η 5 -2,4-dimethylpentadienyl)(η 5 Using (-ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method. The thin film production conditions are as follows. Purge gas: argon, oxygen and ammonia as reactive gases, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa was used as the raw material gas, and the following steps (a) to (l) were considered as one cycle and were repeated 100 times for a total of 48 minutes under the conditions of a substrate temperature of 250°C and a reaction chamber total pressure of 300 Pa.

[0070] (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (e) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds.

[0071] (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. (i) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (j) In addition to (g), 50 sccm of ammonia gas is introduced into the reaction chamber for 3 seconds. (k) The introduction of ammonia gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gas and by-products. (l) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. When the produced thin film was examined by X-ray fluorescence analysis, characteristic X-rays due to ruthenium were detected. The film thickness was calculated from the intensity of the detected X-rays and was found to be 4 nm. Furthermore, when this ruthenium-containing thin film was observed by AFM, the root mean square roughness (RMS) was found to be 2.11.

[0072] Comparative Example 3 Using (2,4-dimethyl-pentadienyl) (ethylcyclopentadienyl) ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method. The thin film production conditions are as follows. Purge gas: argon, oxygen as oxidizing gas, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling under the conditions of a material container temperature of 90°C and a material vapor pressure of 38.1 Pa was used as the raw material gas, and the following steps (a) to (h) were considered as one cycle and were repeated 200 times for a total of 67 minutes under the conditions of a substrate temperature of 250°C and a reaction chamber total pressure of 300 Pa.

[0073] (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber.

[0074] (e) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. The produced thin film was analyzed by X-ray fluorescence analysis, which detected characteristic X-rays due to ruthenium. The film thickness was calculated from the intensity of the detected X-rays to be 21 nm. Furthermore, the composition of this ruthenium-containing thin film was analyzed by X-ray photoelectron spectroscopy, which revealed that the ruthenium content was 92 atom%.

[0075] Reference example 1 Using (2,4-dimethyl-pentadienyl)(ethylcyclopentadienyl)ruthenium as a raw material, a ruthenium-containing thin film was produced on a SiO2 substrate by the ALD method described in (2) after the pretreatment described in (1). The thin film production conditions, consisting of (1) the pretreatment process and (2) the ALD film formation process, are as follows.

[0076] (1) Pretreatment process Purge gas: argon, raw material gas, Carrier gas: argon 10sccm, The raw material vapor vaporized by bubbling at a material container temperature of 90°C and a material vapor pressure of 38.1 Pa was used as the raw material gas. The substrate temperature was 500°C and the total pressure in the reaction chamber was 1000 Pa. One cycle consisted of the following steps (a) and (b), and this was repeated 100 times for a total of 13 minutes. (a) 150 sccm of argon as a purge gas is introduced into the reaction chamber for 3 seconds. (b) In addition to (a), the source gas is introduced into the reaction chamber for 5 seconds.

[0077] (2)ALD film formation process The conditions were as follows: purge gas: argon, oxygen as oxidizing gas, raw material gas: raw material vapor evaporated under the same conditions as in the pretreatment process, substrate temperature: 250°C, total pressure in the reaction chamber: 300 Pa. One cycle consisted of the following steps (a) to (h), and was repeated 100 times for a total of 33 minutes. (a) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (b) In addition to (a), the source gas is introduced into the reaction chamber and allowed to adsorb on the substrate surface for 5 seconds. (c) The introduction of the source gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (d) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber.

[0078] (e) 150 sccm of purge argon gas is introduced into the reaction chamber for 3 seconds, and the reaction chamber pressure is set to 300 Pa. (f) In addition to (e), 100 sccm of oxygen gas is introduced into the reaction chamber for 3 seconds. (g) The introduction of oxygen gas is stopped, and the reaction chamber is evacuated for 2 seconds to remove unreacted gases and by-products. (h) 400 sccm of purge argon gas is introduced into the reaction chamber for 1 second to increase the pressure in the reaction chamber. When the produced thin film was examined by X-ray fluorescence analysis, characteristic X-rays due to ruthenium were detected. The film thickness was calculated from the intensity of the detected X-rays and was found to be 11 nm. Furthermore, when the composition of this ruthenium-containing thin film was analyzed by X-ray photoelectron spectroscopy, the ruthenium content was found to be 88 atom%.

[0079] The ruthenium-containing thin films obtained by the manufacturing methods of Examples 1 to 5 have a smaller root mean square roughness (RMS) than the ruthenium-containing thin films obtained by the manufacturing methods of Comparative Examples 1 and 2, and are excellent in surface smoothness. The ruthenium-containing thin films obtained by the manufacturing methods of Examples 6 and 7 have a higher ruthenium content and are higher purity films than the ruthenium-containing thin films obtained by the manufacturing methods of Comparative Example 3 and Reference Example 1, which do not use a reducing gas. Furthermore, the ruthenium-containing thin films obtained in Examples 8 and 9 are films with excellent surface smoothness, a high ruthenium content, and high purity.

[0080] The entire contents of the specifications, claims, drawings and abstracts of Japanese Patent Application No. 2020-047690 filed on March 18, 2020 and Japanese Patent Application No. 2020-055849 filed on March 26, 2020 are hereby incorporated by reference as the disclosure of the specification of the present invention. [Explanation of symbols]

[0081] 1 Material container 2 Constant temperature bath 3. Reaction Chamber 4 boards 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-sealed rotary pump 12 Exhaust

Claims

1. A method for producing a metal-containing thin film, characterized in that a ruthenium complex represented by the following general formula (1AB) is used as a raw material, and a reducing gas is introduced into a reaction chamber to perform surface treatment of the substrate as a pretreatment that can induce adsorption and nucleation of the ruthenium complex onto the substrate, and then a film is formed on the pretreated substrate using an oxidizing gas by the ALD method. [Chemical formula 1] (In the formula, R 1 and R 2 each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R 3 and R 4 each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and Z represents an oxygen atom or CH.)

2. A method for producing a metal-containing thin film as described in claim 1, characterized in that, in the film formation, after supplying an oxidizing gas, a reducing gas is further supplied.

3. A method for producing a metal-containing thin film according to claim 1 or 2, wherein in general formula (1AB), R 1 and R 2 are each independently an alkyl group having 1 to 6 carbon atoms, R 3 and R 4 are alkyl groups having 1 to 4 carbon atoms, and Z is an oxygen atom or CH.

4. A method for producing a metal-containing thin film according to any one of claims 1 to 3, wherein in general formula (1AB), R 1 and R 2 are each independently an alkyl group having 1 to 4 carbon atoms, R 3 and R 4 are each an alkyl group having 1 to 4 carbon atoms, and Z is an oxygen atom or CH.

5. In general formula (1AB), R １ and R ２ are each independently an alkyl group having 1 to 4 carbon atoms, and R ３ and R ４ 5. The method for producing a metal-containing thin film according to claim 1, wherein is a methyl group, and Z is an oxygen atom or CH.

6. In general formula (1AB), R １ is an ethyl group, and R ２ is a hydrogen atom, and R ３ and R ４ 6. The method for producing a metal-containing thin film according to claim 1, wherein is a methyl group, and Z is an oxygen atom or CH.

7. A method for producing a metal-containing thin film according to claim 1, wherein the substrate is heated to 200° C. or higher in the pretreatment.

8. A method for producing a metal-containing thin film according to claim 1, wherein ammonia gas or hydrogen gas is used as the reducing gas used in the pretreatment.

9. A method for producing a metal-containing thin film according to claim 1, wherein ammonia gas is used as the reducing gas used in the pretreatment.

10. A method for producing a metal-containing thin film as described in claim 2, wherein ammonia gas is used as the reducing gas used in the film formation.

11. A method for producing a metal-containing thin film according to claim 1, wherein oxygen gas or ozone gas is used as the oxidizing gas used in the film formation.

12. A method for producing a metal-containing thin film according to claim 1, wherein oxygen gas is used as the oxidizing gas used in the film formation.

13. The method for producing a metal-containing thin film according to claim 1, wherein the substrate has a surface made of a metal oxide film or a metal nitride film.

14. The method for producing a metal-containing thin film according to claim 13, wherein the substrate has a surface made of silicon oxide, a composite metal oxide film, tantalum nitride, or titanium nitride.

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