Method for Producing Metal or Metalloid Containing Films

Abstract

The present invention is in the field of methods for preparing inorganic metal- or semi-metal-containing films. The methods include: (a) depositing a gaseous metal or metalloid-containing compound onto a solid substrate; (b) treating a solid substrate with a compound represented by general formula (I), (II), or (III) in a gaseous state; [Formula 1] TIFF2022536111000031.tif50145 (wherein A is NR, NR2, PR, PR2, O, OR, S, or SR; E is N, NR, P, PR, O or S; n is 1, 2, or 3; R is an alkyl group, an alkenyl group, an aryl group, or a silyl group; R' is hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group; A, E, and n are selected such that the compound of general formula (I), (II), or (III) is electronically neutral. and contacting the compound of Includes:

Description

[Technical field]

[0001] The present invention is in the field of methods, particularly atomic layer deposition methods, for producing inorganic metal or metalloid containing films on substrates. [Background technology]

[0002] For example, in the semiconductor industry, the miniaturization increases the need for inorganic thin films on substrates, while the quality requirements for such films are stringent. Thin films of metals or metalloids are used for various purposes, e.g. barrier layers, conductive functions or capping layers. Several methods are known for forming metal or metalloid films. One of them is to deposit a film-forming compound from a gaseous state onto a substrate. In order to bring the metal or metalloid atoms into a gaseous state at moderate temperatures, it is necessary to provide volatile precursors, for example by complexing the metal or metalloid with suitable ligands. These precursors must be sufficiently stable against evaporation, but on the other hand must be sufficiently reactive to react with the surface of the deposit.

[0003] EP 3 121 309 A1 discloses a method for depositing aluminum nitride films from a tris(dialkylamino)aluminum precursor. However, this precursor is not stable enough for applications requiring high quality films.

[0004] In order to convert the deposited metal or metalloid complexes to metal or metalloid films, it is usually necessary to expose the deposited metal or metalloid complexes to a reducing agent. Typically, hydrogen gas is used to convert the deposited metal or metalloid complexes to metal or metalloid films. Hydrogen works well as a reducing agent for relatively noble metals such as copper or silver, but does not give satisfactory results for more electropositive metals such as titanium or aluminum.

[0005] WO 2013 / 070 702 A1 discloses a method for depositing metal films using aluminium hydride coordinated with diamines as reducing agents, which generally give good results, but for demanding applications higher vapor pressure, stability and / or reduction potential are required.

[0006] D. Mukherjee et al., Chemical Communications, Vol. 53 (2017), pp. 3593-3496, disclose alane complexes with chelating ligands. However, since the compounds are used only for organic synthesis in solution, their suitability for preparing inorganic metal- or metalloid-containing films is not recognized by the authors. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] EP 3 121 309 A1 [Patent Document 2] WO 2013 / 070 702 A1 [Non-patent literature]

[0008] [Non-Patent Document 1] D. Mukherjee et al., Chemical Communications, Vol. 53 (2017), pp. 3593-3496 Summary of the Invention [Problem to be solved by the invention]

[0009] It was therefore an object of the present invention to provide a method for preparing inorganic metal- or metalloid-containing films with low impurities in the film. The processing material is easy to handle; in particular, it is possible to evaporate it with as little decomposition as possible. Furthermore, the processing material does not decompose at the deposition surface under the process conditions, but at the same time has sufficient reactivity to participate in surface reactions. In order to avoid contamination of the film, all reaction by-products are volatile. Furthermore, it is possible to adjust the method so that the metal or metalloid atoms in the processing material are volatile or incorporated into the film. Furthermore, the method is versatile and can be applied to the production of a wide variety of metals, including electropositive metal or metalloid films. [Means for solving the problem]

[0010] These objectives are: (a) depositing a gaseous metal or metalloid containing compound onto a solid substrate; (b) treating a solid substrate with a compound represented by general formula (I), (II), or (III) in a gaseous state; [ka] wherein A is NR, NR2, PR, PR2, O, OR, S, or SR; E is N, NR, P, PR, O or S; n is 1, 2, or 3; R is an alkyl group, an alkenyl group, an aryl group, or a silyl group; R' is a hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group; A, E, and n are selected such that the compound of general formula (I), (II), or (III) is electronically neutral. and contacting the compound of This was accomplished by a method for preparing an inorganic metal or metalloid containing film, comprising:

[0011] The present invention further relates to the use of a compound of general formula (I), (II) or (III) as a reducing agent in a vapor deposition process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Preferred embodiments of the invention can be found in the specification and claims. Combinations of the different embodiments are within the scope of the invention.

[0013] The method according to the invention is suitable for preparing inorganic metal- or metalloid-containing films. Inorganic in the context of the present invention refers to a material that contains at least 5% by weight, preferably at least 10% by weight, more preferably at least 20% by weight, in particular at least 30% by weight of at least one metal or metalloid. Typically, inorganic films contain carbon only in the form of carbide phases, including mixed carbide phases, such as nitride carbide phases. The carbon content of carbon that is not part of the carbide phase in the inorganic film is preferably less than 5% by weight, more preferably less than 1% by weight, in particular less than 0.2% by weight. Preferred examples of inorganic metal- or metalloid-containing films include films containing metal or metalloid nitride films, metal or metalloid carbide films, metal or metalloid carbonitride films, metal or metalloid alloy films, intermetallic compound films, or mixtures thereof.

[0014] The film prepared by the method according to the invention contains a metal or metalloid. It is possible that the film contains one metal or metalloid, or two or more metals and / or metalloids. Metals include Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Bi. Metalloids include B, Si, Ge, As, Sb, Se, Te. Preferably, the metal or metalloid is more electropositive than Cu, more preferably more electropositive than Ni. In particular, the metal or semimetal is Ti, Ta, Mn, Mo, W, Ge, Ga, As, In, Sb, Te, Al or Si.

[0015] The solid substrate can be any solid material. These include, for example, metals, semi-metals, oxides, nitrides, and polymers. It is also possible for the substrate to be a mixture of different materials. Examples of metals include aluminum, steel, zinc, and copper. Examples of semi-metals include silicon, germanium, and gallium arsenide. Examples of oxides include silicon dioxide, titanium dioxide, and zinc oxide. Examples of nitrides include silicon nitride, aluminum nitride, titanium nitride, and gallium nitride. Examples of polymers include polyethylene terephthalate (PET), polyethylene naphthalene-dicarboxylic acid (PEN), and polyamides.

[0016] The solid substrates can have any shape. These include sheets, plates, films, fibers, substrates with particles of various sizes, grooves or other depressions. The solid substrates can have any size. If the solid substrate has a particulate shape, the size of the particles can range from less than 100 nm to several centimeters, preferably 1 μm to 1 mm. It is preferable to keep the particles or fibers moving while the metal or metalloid containing compound is deposited on them to avoid them sticking to each other. This can be achieved, for example, by stirring, rotating drum, or fluidized bed techniques.

[0017] According to the present invention, the solid substrate is contacted with a compound of general formula (I), (II), or (III) in the gas phase. R' in the compound of general formula (I), (II), or (III) is hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group, preferably hydrogen or an alkyl group, in particular hydrogen, methyl, or ethyl. R' may be the same or different from each other. Preferably, all R' are the same.

[0018] The alkyl group may be linear or branched. Examples of linear alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl. Examples of branched alkyl groups include iso-propyl, iso-butyl, sec-butyl, tert-butyl, 2-methyl-pentyl, neo-pentyl, 2-ethyl-hexyl, cyclopropyl, cyclohexyl, indanyl, and norbornyl. Preferably, the alkyl group is a C1-C8 alkyl group, more preferably a C1-C6 alkyl group, and especially a C1-C4 alkyl group, such as methyl, ethyl, iso-propyl, or tert-butyl.

[0019] Alkenyl groups contain at least one carbon-carbon double bond. This double bond can include the carbon atom where R' is attached to the rest of the molecule, or it can be located further away from where R' is attached to the rest of the molecule. Alkenyl groups can be straight-chained or branched. Examples of straight-chained alkenyl groups containing a double bond including the carbon atom where R' is attached to the rest of the molecule include 1-ethenyl, 1-propenyl, 1-n-butenyl, 1-n-pentenyl, 1-n-hexenyl, 1-n-heptenyl, 1-n-octenyl. Examples of straight-chained alkenyl groups containing a double bond that is located further away from where R' is attached to the rest of the molecule include 1-n-propen-3-yl, 2-buten-1-yl, 1-buten-3-yl, 1-buten-4-yl, 1-hexen-6-yl. Examples of branched alkenyl groups containing a double bond involving the carbon atom where R' is attached to the remainder of the molecule include 1-propen-2-yl, 1-n-buten-2-yl, 2-buten-2-yl, cyclopenten-1-yl, cyclohexen-1-yl. Examples of branched alkenyl groups containing a double bond that is located further away from where R' is attached to the remainder of the molecule include 2-methyl-1-buten-4-yl, cyclopenten-3-yl, cyclohexen-3-yl. Examples of alkenyl groups with more than one double bond include 1,3-butadien-1-yl, 1,3-butadien-2-yl, cyclopentadien-5-yl.

[0020] The aryl group includes aromatic hydrocarbons, such as phenyl, naphthalyl, anthracenyl, phenanthrenyl, and heteroaromatic groups, such as pyrryl, furanyl, thienyl, pyridinyl, quinoyl, benzofuryl, benzothiophenyl, thienothienyl. Also, a combination of these groups or groups, such as biphenyl, thienophenyl, or furanylthienyl, can be used. The aryl group can be substituted with halogens, such as fluoride, chloride, bromide, iodide, pseudohalogens, such as cyanide, cyanate, thiocyanate, alcohols, alkyl or alkoxy chains. Aromatic hydrocarbons are preferred, and phenyl is more preferred.

[0021] Silyl group is typically a silicon atom with three substituents. Preferably, silyl group has formula SiX3, where X is hydrogen, alkyl group, aryl group or silyl group, independently of each other. All three X can be the same, or two X are the same and the remaining X are different, or all three X can be different from each other, preferably all X are the same. Alkyl group and aryl group are as described above. Examples of silyl group include SiH3, methylsilyl, trimethylsilyl, triethylsilyl, tri-n-propylsilyl, tri-iso-propylsilyl, tricyclohexylsilyl, dimethyl-tert-butylsilyl, dimethylcyclohexylsilyl, methyl-di-iso-propylsilyl, triphenylsilyl, phenylsilyl, dimethylphenylsilyl, pentamethyldisilyl.

[0022] A in the compounds of general formula (I) or (II) is NR, NR2, PR, PR2, O, OR, S, or SR, i.e. a nitrogen atom carrying one or two substituents R, a phosphorus atom carrying one or two substituents R, an oxygen atom, an oxygen atom carrying a substituent R, a sulfur atom, or a sulfur atom carrying a substituent R. R is an alkyl group, an alkenyl group, an aryl group, or a silyl group. The same definition as for R' above applies. Preferably, R is an alkyl group or a silyl group, more preferably methyl, ethyl, iso-propyl, sec-butyl, tert-butyl, or trimethylsilyl, in particular methyl or ethyl. All A in the compounds of general formula (I) or (II) can be the same or different from each other.

[0023] E in the compounds of general formula (II) or (III) is N, NR, P, PR, O or S, i.e. nitrogen atom, nitrogen atom with substituent R, phosphorus atom, phosphorus atom with substituent R, oxygen atom or sulfur atom. The above definition of R applies. E in the compounds of general formula (II) or (III) can be the same or different from each other.

[0024] Every R and R' can be a separate substituent, or two R or two R', or R and R' together can form a ring, preferably a 4- to 8-membered ring, in particular a 5- or 6-membered ring.

[0025] According to the invention, n, the number of hydrogen atoms bonded to the aluminum atom in the compounds of general formula (I), (II) or (III), is 1, 2 or 3, preferably 1 or 2, in particular 1.

[0026] According to the present invention, A, E and n are selected so that the compound of general formula (I), (II) or (III) is electronically neutral. When A is NR, PR, O or S, A provides an anionic donor atom to the ligand, whereas when A is NR2, PR2, OR or SR, A provides a neutral donor atom. When E is N or P, E provides an anionic donor atom, whereas when E is NR, PR, O or S, it provides a neutral donor atom. To make the compound of general formula (I), (II) or (III) electronically neutral, the sum of the number of anionic donor atoms and the number of hydrogen atoms bonded to the aluminum atom is less than Al. 3+ It needs to be 3 to compensate for the charge of the atom.

[0027] Preferably, the compound of general formula (I) is one of the following general formulae:

[0028] [ka] TIFF0007636754000003.tif35150 TIFF0007636754000004.tif35150 TIFF0007636754000005.tif3598

[0029] Preferred examples of compounds of formula (I) with reference to these formulae are shown in the following table.

[0030] [Table 1] TIFF0007636754000007.tif250107 TIFF0007636754000008.tif148118

[0031] Et stands for ethyl.

[0032] The synthesis of some of the compounds of general formula (I) is described, for example, by C. Jones in the Journal of the Chemical Society, Dalton Transactions, volume 1996, pages 829-833.

[0033] Preferably, the compound of general formula (II) is one of the following general formulae:

[0034] [ka] TIFF0007636754000010.tif41145 TIFF0007636754000011.tif42145 TIFF0007636754000012.tif43145 TIFF0007636754000013.tif4395

[0035] Preferred examples of the compounds of formula (II) with reference to these formulae are shown in the following table.

[0036] [Table 2] TIFF0007636754000015.tif248109 TIFF0007636754000016.tif248105 TIFF0007636754000017.tif35112

[0037] Et stands for ethyl and Ph stands for phenyl.

[0038] Preferably, the compound of general formula (III) is one of the following general formulae:

[0039] [ka] TIFF0007636754000019.tif48141 TIFF0007636754000020.tif48141 TIFF0007636754000021.tif48141 TIFF0007636754000022.tif48141 TIFF0007636754000023.tif4845

[0040] Preferred examples of the compounds of formula (III) with reference to these formulae are shown in the following table.

[0041] [Table 3] TIFF0007636754000025.tif218114 TIFF0007636754000026.tif248106 TIFF0007636754000027.tif249107 TIFF0007636754000028.tif39110

[0042] Et stands for ethyl and Ph stands for phenyl.

[0043] Preferably, R does not have a hydrogen atom in position 1, i.e., R does not have a hydrogen atom bonded to a nitrogen or oxygen atom and thus to an atom in the beta position relative to the aluminum atom. Also, preferably, R'' does not have a hydrogen atom in position 1. More preferably, both R and R'' do not have a hydrogen atom in position 1. Examples include alkyl groups with two alkyl side groups in position 1, i.e. 1,1-dialkylalkyl, e.g. tert-butyl, 1,1-dimethylpropyl; alkyl groups with two halogens in position 1, e.g. trifluoromethyl, trichloromethyl, 1,1-difluoroethyl; trialkylsilyl groups, e.g. trimethylsilyl, triethylsilyl, dimethyl-tert-butylsilyl; aryl groups, especially phenyl, or alkyl-substituted phenyl, e.g. 2,6-diisopropylphenyl, 2,4,6-triisopropylphenyl. Alkyl groups with no hydrogen atom in position 1 are particularly preferred.

[0044] The compounds of general formula (I), (II) or (III) preferably have a molecular weight of less than or equal to 1000 g / mol, more preferably less than or equal to 800 g / mol, even more preferably less than or equal to 600 g / mol, in particular less than or equal to 500 g / mol.

[0045] Preferably, the compounds of general formula (I), (II) or (III) have a melting point in the range of −80 to 125° C., preferably −60 to 80° C., even more preferably −40 to 50° C., in particular −20 to 20° C. It is advantageous if the compounds of general formula (I), (II) or (III) are melted to obtain a transparent liquid that does not change up to the decomposition temperature.

[0046] The compounds of general formula (I), (II) or (III) preferably have a decomposition temperature of at least 80°C, more preferably at least 100°C, in particular at least 120°C, for example at least 150°C. In many cases, the decomposition temperature is not more than 250°C. The compounds of general formula (I), (II) or (III) have a high vapor pressure. The vapor pressure is preferably at least 1 mbar at 200°C, more preferably at 150°C, in particular at 120°C. Usually, the temperature at which the vapor pressure is 1 mbar is at least 50°C.

[0047] In order to obtain the best results, the compound of general formula (I), (II) or (III) used in the method according to the present invention is used with high purity.High purity means that the material used contains at least 90% by weight, preferably at least 95% by weight, more preferably at least 98% by weight, especially at least 99% by weight of the compound of general formula (I), (II) or (III) or the metal- or metalloid-containing compound.Purity can be determined by elemental analysis according to DIN 51721 (Pruefung fester Brennstoffe - Bestimmung des Gehaltes an Kohlenstoff und Wasserstoff - Verfahren nach Radmacher-Hoverath, August 2001).

[0048] The compounds of general formula (I), (II) or (III) are contacted with the solid substrate from the gaseous state. They can be brought into the gaseous state, for example, by heating them to a high temperature. In any case, a temperature below the decomposition temperature of the compounds of general formula (I), (II) or (III) must be selected. The decomposition temperature is the temperature at which the original compounds of general formula (I), (II) or (III) start to change their chemical structure and composition. The heating temperature is preferably in the range of 0°C to 300°C, more preferably 10°C to 250°C, even more preferably 20°C to 200°C, in particular 30°C to 150°C.

[0049] Another method of putting the compound of general formula (I), (II) or (III) into a gaseous state is direct liquid injection (DLI), for example as described in US 2009 / 0 226 612 A1. In this method, the compound of general formula (I), (II) or (III) is usually dissolved in a solvent and sprayed in a carrier gas or vacuum. If the vapor pressure and temperature of the compound of general formula (I), (II) or (III) are sufficiently high and the pressure is sufficiently low, the compound of general formula (I), (II) or (III) will be in a gaseous state. Various solvents can be used, provided that the compound of general formula (I), (II) or (III) shows sufficient solubility in the solvent, such as at least 1 g / l, preferably at least 10 g / l, more preferably at least 100 g / l. Examples of these solvents include coordinating solvents such as tetrahydrofuran, dioxane, diethoxyethane, pyridine, or non-coordinating solvents such as hexane, heptane, benzene, toluene or xylene. Mixtures of solvents are also suitable.

[0050] Alternatively, the compound of general formula (I), (II), or (III) can be brought into a gaseous state by direct liquid evaporation (DLE), for example as described by J. Yang et al. (Journal of Materials Chemistry, 2015). In this method, the compound of general formula (I), (II), or (III) is mixed with a solvent, for example a hydrocarbon such as tetradecane, and heated below the boiling point of the solvent. The compound of general formula (I), (II), or (III) is brought into a gaseous state by evaporating the solvent. This method has the advantage that no particulate contaminants are formed on the surface.

[0051] It is preferred to bring the compound of general formula (I), (II) or (III) into a gaseous state under reduced pressure. In this way, the method of the present invention can usually be carried out at a low heating temperature, which leads to a reduction in the decomposition of the compound of general formula (I), (II) or (III). It is also possible to use high pressure to push the compound of general formula (I), (II) or (III) in a gaseous state towards the solid substrate. For this purpose, inert gases such as nitrogen or argon are often used as carrier gases. The pressure is preferably between 10 bar and 10 bar. -7 mbar, more preferably 1 bar to 10 -3 It is in millibars, in particular between 1 and 0.01 millibars, for example 0.1 millibars.

[0052] Typically, the compound of general formula (I), (II), or (III) acts as a reducing agent in the method of the present invention. According to the present invention, the metal or metalloid containing compound is deposited on the solid substrate from the gaseous state before contacting with the compound of general formula (I), (II), or (III). The metal or metalloid containing compound is usually reduced to a metal, a metal nitride, a metal carbide, a metal carbonitride, a metal alloy, an intermetallic compound, or a mixture thereof. A metal film in the context of the present invention is generally a metal having a molecular weight of at least 10 ... 4 S / m, preferably at least 10 5 S / m, especially at least 10 6 It is a metal or semi-metal containing film with high electrical conductivity, S / m.

[0053] The compounds of general formula (I), (II), or (III) have a low tendency to form permanent bonds with the surface of the solid substrate on which the metal- or metalloid-containing compounds are deposited. As a result, the metal- or metalloid-containing films are less likely to be contaminated with reaction by-products of the compounds of general formula (I), (II), or (III). Preferably, the metal- or metalloid-containing films contain less than 5% by weight, more preferably less than 1% by weight, particularly less than 0.5% by weight, for example less than 0.2% by weight, of nitrogen in total.

[0054] The metal or metalloid-containing compound contains at least one metal or metalloid atom. Metals include Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Bi. Metalloids include B, Si, Ge, As, Sb, Se, Te. Preferably, the metal or metalloid-containing compound contains a metal or metalloid that is more electropositive than Cu, more preferably more electropositive than Ni. In particular, the metal or metalloid containing compound contains Ti, Ta, Mn, Mo, W, Ge, Ga, As, In, Sb, Te, Al or Si. It is also possible that two or more metal or metalloid containing compounds are deposited on a surface simultaneously or sequentially. When two or more metal or metalloid containing compounds are deposited on a solid substrate, all metal or metalloid containing compounds can contain the same metal or metalloid, or different metals or metalloids, and preferably they contain different metals or metalloids.

[0055] Metal or metalloid-containing compounds that can be put into a gaseous state are suitable.These compounds include metal or metalloid alkyls, such as dimethylzinc, trimethylaluminum; metal alkoxylates, such as tetramethoxysilicon, tetra-isopropoxyzirconium or tetra-isopropoxytitanium; metal or metalloid cyclopentadienyl complexes, such as pentamethylcyclopentadienyl-trimethoxytitanium or di(ethylcyclopentadienyl)manganese; metal or metalloid carbenes, such as tris(neopentyl)neopentylidenetantalum or bisimidazolidinylideneruthenium chloride; metal or metalloid halides, such as aluminum trichloride. , tantalum pentachloride, titanium tetrachloride, molybdenum pentachloride, germanium tetrachloride, gallium trichloride, arsenic trichloride or tungsten hexachloride; carbon monoxide complexes such as chromium hexacarbonyl or nickel tetracarbonyl; amine complexes such as bis(tert-butylimino)bis(dimethylamino)molybdenum, bis(tert-butylimino)bis(dimethylamino)tungsten or tetrakis(dimethylamino)titanium; diketonate complexes such as tris(acetylacetonato)aluminum or bis(2,2,6,6-tetramethyl-3,5-heptanedionato)manganese. Metal or semimetal halides are preferred, especially aluminum chloride, aluminum bromide and aluminum iodide. The molecular weight of the metal or semimetal containing compound is preferably 1000 g / mol or less, more preferably 800 g / mol or less, in particular 600 g / mol or less, for example 500 g / mol or less.

[0056] Preferably, the method of the invention comprises the following sequence of steps: (a) depositing a gaseous metal or metalloid containing compound onto a solid substrate; (b) contacting the solid substrate having the metal or metalloid-containing compound deposited thereon with a compound of general formula (I), (II), or (III); The process is carried out as an atomic layer deposition (ALD) method, comprising: (a) and (b). Preferably, the sequence of steps including (a) and (b) is carried out at least twice, more preferably at least 5 times, even more preferably at least 10 times, and especially at least 50 times. In many cases, the sequence of steps including (a) and (b) is carried out 1000 times or less.

[0057] In general, it is preferable to purge the substrate and the surrounding equipment with an inert gas each time the solid substrate is contacted with a gaseous metal or metalloid-containing compound or a compound of general formula (I), (II), or (III). Preferred examples of the inert gas are nitrogen and argon. Purging can be performed for 1 second to 1 minute, preferably 5 to 30 seconds, more preferably 10 to 25 seconds, and particularly 15 to 20 seconds.

[0058] Preferably, the temperature of the substrate is 5° C. to 40° C., for example 20° C., higher than the temperature at which the metal- or metalloid-containing compound is converted into a gaseous state. The temperature of the substrate is preferably from room temperature to 400° C., more preferably from 100 to 300° C., for example from 150 to 220° C.

[0059] Preferably, after depositing the metal or metalloid-containing compound on the solid substrate, and before contacting the solid substrate with the deposited metal or metalloid-containing compound with a compound of general formula (I), (II), or (III), the solid substrate with the deposited metal or metalloid-containing compound is contacted with an acid in the gas phase. Without being bound by theory, it is believed that protonation of the ligand of the metal or metalloid-containing compound promotes its decomposition and reduction. Suitable acids include hydrochloric acid and carboxylic acids, preferably carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, or trifluoroacetic acid, especially formic acid.

[0060] Alternatively, aluminum can be deposited from a compound of general formula (I), (II), or (III). In this case, the compound of general formula (I), (II), or (III) is adsorbed on the surface of the solid substrate, for example, because the surface of the solid substrate has reactive groups such as OH groups or the temperature of the solid substrate is high enough. Preferably, the adsorbed compound of general formula (I), (II), or (III) is decomposed.

[0061] The decomposition can be carried out in various ways. The temperature of the solid substrate can be raised above the decomposition temperature. In this case, the method of the invention is a chemical vapor deposition (CVD) method. Typically, the solid substrate is heated to a temperature in the range of 300-1000°C, preferably in the range of 350-600°C.

[0062] Furthermore, it is possible to expose the deposited compound of general formula (I), (II) or (III) to a plasma, for example an oxygen plasma, a hydrogen plasma, an ammonia plasma or a nitrogen plasma; to an oxidant, for example oxygen, oxygen radicals, ozone, nitrous oxide (NO), nitric oxide (NO), nitrogen dioxide (NO) or hydrogen peroxide; to ammonia or an ammonia derivative, for example tert-butylamine, iso-propylamine, dimethylamine, methylethylamine or diethylamine; to hydrazine or a hydrazine derivative, for example N,N-dimethylhydrazine; to a solvent, for example water, an alkane or a tetrachlorocarbon; or to a boron compound, for example a borane. The choice depends on the chemical structure of the desired layer. In the case of aluminum oxide, it is preferred to use an oxidant, a plasma or water, in particular oxygen, water, an oxygen plasma or ozone. In the case of aluminum nitride, ammonia, hydrazine, a hydrazine derivative, a nitrogen plasma or an ammonia plasma are preferred. In the case of aluminum boride, a boron compound is preferred. In the case of aluminum carbide, an alkane or a tetrachlorocarbon is preferred. In the case of aluminum carbonitride, mixtures containing alkanes, tetrachlorocarbons, ammonia and / or hydrazine are preferred.

[0063] Preferably, the method of the invention comprises the following sequence of steps: (c) contacting the solid substrate with a compound of general formula (I), (II), or (III); (d) decomposing the adsorbed compound of general formula (I), (II), or (III); Preferably, the sequence of steps including (c) and (d) is performed at least twice, more preferably at least 5 times, even more preferably at least 10 times, and especially at least 50 times. In many cases, the sequence of steps including (c) and (d) is performed 1000 times or less.

[0064] In this case, the temperature of the substrate is preferably 5° C. to 40° C., for example 20° C. higher than the temperature of the place where the metal- or metalloid-containing compound is made into a gaseous state. The temperature of the substrate is preferably from room temperature to 400° C., more preferably from 100 to 300° C., for example from 150 to 220° C.

[0065] When the temperature of the substrate is maintained below the decomposition temperature of the metal or metalloid-containing compound in the method according to the invention, typically a monolayer is deposited on the solid substrate. Once molecules of the metal or metalloid-containing compound are deposited on the solid substrate, they are usually unlikely to be further deposited thereon. Thus, the deposition of the metal or metalloid-containing compound on the solid substrate preferably represents a self-limiting process step. Typical layer thicknesses of self-limiting deposition process steps are 0.01-1 nm, preferably 0.02-0.5 nm, more preferably 0.03-0.4 nm, in particular 0.05-0.2 nm. The layer thickness is typically measured by ellipsometry as described in PAS 1022 DE (References zur Bestimmung von optischen und dielektrischen Materialeigenschaften sowie der Schichtdicke duenner Schichten mittels Ellipsometrie; February 2004).

[0066] Exposure of the substrate to the compound of general formula (I), (II), or (III), or the metal- or metalloid-containing compound, can take place for milliseconds to minutes, preferably 0.1 seconds to 1 minute, especially 1 second to 10 seconds. The longer the exposure of the solid substrate to the compound of general formula (I), (II), or (III), or the metal- or metalloid-containing compound, at a temperature below the decomposition temperature of the compound of general formula (I), (II), or (III), or the metal- or metalloid-containing compound, the more ordered the film formed, with fewer defects.

[0067] A particular advantage of the method according to the invention is that the compounds of general formula (I), (II) or (III) are very versatile, which allows the parameters of the method according to the invention to be varied in a wide range, and thus the method according to the invention includes both CVD and ALD methods.

[0068] The method according to the invention results in an inorganic metal or semi-metal containing film. The film can be only a monolayer of metal or can be as thick as 0.1 nm to 1 μm, preferably 0.5 to 50 nm. The film may contain defects such as holes. However, these defects generally occupy less than half of the surface area covered by the film. Preferably, the film has a very uniform film thickness, meaning that there is little variation in film thickness at different locations on the substrate, usually less than 10%, preferably less than 5%. Furthermore, preferably, the film is a conformal film on the surface of the substrate. Suitable methods for determining film thickness and uniformity are XPS or ellipsometry.

[0069] The film obtained by the method according to the invention can be used in electronic devices. The electronic devices can have structural features of various sizes, for example from 1 nm to 100 μm, such as 10 nm, 14 nm or 22 nm. The method for forming the film for electronic devices is particularly suitable for very fine structures. Electronic devices with sizes below 1 μm are therefore preferred. Examples of electronic devices include field effect transistors (FETs), solar cells, light emitting diodes, sensors or capacitors. In optical devices such as light emitting diodes or light sensors, the film obtained by the method according to the invention helps to increase the refractive index of the light reflecting layer.

[0070] A preferred electronic device is a transistor. Preferably, the film functions as a chemical barrier metal in the transistor. A chemical barrier metal is a material that reduces diffusion of adjacent layers while maintaining electrical connectivity.

Claims

1. (a) depositing a gaseous metal or metalloid containing compound onto a solid substrate; (b) treating the solid substrate with a gaseous mixture of a compound represented by general formula (I), (II), or (III) 【Chemistry 1】 (Wherein, A is NR, NR ２ , P.R. ２ , O or OR; E is N, NR, P, PR or O; n is 1, 2, or 3; R is an alkyl group, an alkenyl group, an aryl group, or a silyl group; R' is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a silyl group; A, E, and n are selected such that the compound of general formula (I), (II), or (III) is electronically neutral. and contacting the compound with 1. A method for preparing an inorganic metal or metalloid containing film comprising:

2. 2. The method of claim 1, wherein R is methyl, ethyl, iso-propyl, sec-butyl, tert-butyl, trimethylsilyl.

3. 3. The method of claim 1 or 2, wherein R does not have a hydrogen atom at the 1-position.

4. 4. The method of claim 1, wherein n is 1 or 2.

5. The method according to any one of claims 1 to 4, wherein the compound of general formula (I), (II) or (III) has a melting point of -80 to 125°C.

6. 6. The method of any one of claims 1 to 5, wherein the metal or metalloid containing compound contains Ti, Ta, Mn, Mo, W, Ge, Ga, As, In, Sb, Te, Al, or Si.

7. 7. The method of claim 1, wherein the metal or metalloid containing compound is a metal or metalloid halide.

8. 8. The method of any one of claims 1 to 7, wherein the inorganic metal or metalloid containing film contains a metal, a metal nitride, a metal carbide, a metal carbonitride, a metal alloy, an intermetallic compound, or a mixture thereof.

9. The method according to any one of claims 1 to 8, wherein the sequence of steps including steps (a) and (b) is carried out at least twice.

10. 10. The method of claim 1 , which is an atomic layer deposition method.

11. 11. The method according to any one of claims 1 to 10, wherein the compound of general formula (I), (II) or (III) has a molecular weight of less than or equal to 600 g / mol.

12. 12. The method according to any one of claims 1 to 11, wherein the compound of general formula (I), (II) or (III) has a vapour pressure of at least 1 mbar at a temperature of 200°C.

13. 13. The method of any one of claims 1 to 12, wherein the inorganic metal or metalloid containing film contains less than 5% by weight of nitrogen.

14. A method of using a compound of general formula (I), (II) or (III) as a reducing agent in a vapor deposition process.

15. The method of claim 14, wherein the vapor deposition process is an atomic layer deposition process.

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