Group 13 metal compounds for ald applications

Abstract

The present invention relates to aluminum, gallium and indium metal complexes, and methods of using these complexes as precursors for depositing metal-containing films, particularly by atomic layer deposition.

Description

[0001] Invention Field This invention relates to aluminum, gallium, and indium metal complexes, and methods for using these complexes as precursors for depositing metal-containing films, particularly by atomic layer deposition. Background Technology

[0002] Metal-containing films are used in semiconductor and electronic applications. Chemical vapor deposition (CVD) and atomic layer deposition (ALD) have been the primary deposition techniques for producing thin films for semiconductor devices. These methods enable the creation of conformal films (metals, metal oxides, metal nitrides, metal silicides, etc.) through the chemical reaction of metal-containing compounds (precursors). The chemical reaction occurs on surfaces that may include metals, metal oxides, metal nitrides, metal silicides, and other surfaces. In CVD and ALD, precursor molecules play a crucial role in obtaining high-quality films with high conformability and low impurities. The precursor needs to have appropriate vapor pressure and sufficient thermal stability. Furthermore, it needs to be vaporized in a stable supply to form the film via CVD or ALD methods. In CVD and ALD processes, substrate temperature is an important consideration in selecting precursor molecules. Precursor molecules should preferably be stable at typical substrate temperatures, for example, in the range of 150 to 600°C. Furthermore, the preferred precursor can be delivered to the reaction vessel in either a liquid or gas phase. A liquid precursor at its evaporation temperature generally delivers the precursor to the reaction vessel more uniformly than a solid precursor. While it is sufficient for the precursor to be liquid at the delivery temperature, it is preferred that the precursor be liquid at room temperature. This has the advantage of reducing the likelihood of condensation should any cold spots exist in the precursor delivery system. Furthermore, handling compounds that are liquid at room temperature is technically easier, for example, in filling the container to which the precursor is thus applied.

[0003] The ALD process uses two or more different vapor-phase precursors to deposit thin layers of solid materials. The substrate surface on which the film is deposited is exposed to a specific dose of the vapor from a first precursor. Any excess unreacted vapor from this precursor is then pumped away, for example, by purging with an inert gas. Next, a dose of vapor from a second precursor is brought to the surface and causes it to react. This cycle can be repeated to build thicker films. A particularly important aspect of this method is that the ALD reaction is self-limiting, as only a certain maximum thickness can be formed in each cycle, after which no further deposition is possible, even if excess reactants are available. Due to this self-limiting characteristic, the ALD reaction produces coatings with highly uniform thickness not only on flat substrate surfaces but also in narrow holes and trenches, as well as on other three-dimensional surfaces, making this technology indispensable to the semiconductor industry.

[0004] Indium-containing thin films hold significant technological importance. Such films can contain metallic indium or indium compounds, such as indium oxide, indium nitride, and indium sulfide. In thin-film photovoltaic devices, mixed oxide-sulfide forms of indium are used as electron transport layers, and copper-indium-gallium sulfides are used as absorber layers. The most common application to date is in indium tin oxide (ITO), a transparent conductive oxide (TCO) widely used in flat panel displays, touch-sensitive displays, and thin-film solar cells. Furthermore, indium gallium zinc oxide (IGZO) from the TCO group is gaining increasing attention in the semiconductor industry. Due to the increasing demand for highly conformal, very thin indium-containing films as part of multi-component compositions, it is advantageous to use low-melting-point, highly volatile compounds with low and wide ALD windows as precursors for indium-containing films.

[0005] Possible applications for Ga-containing films include, for example, IGZO thin films in the semiconductor industry or gallium nitride thin films as important III-V semiconductors in the display industry. Aluminum oxide films formed from ALDs can be used, for example, as gate dielectrics or protective coatings, such as gas barrier layers. For instance, metallic aluminum can be used as a metal for interconnects.

[0006] Precursors for ALD (Alternating Current Deposition) of films containing Group 13 metals are primarily alkyl precursors, such as trimethylindium (TMI), trimethylgallium (TMG), or trimethylaluminum (TMA). These precursors share highly volatile and extremely reactive properties, enabling a wide variety of ALD processes on diverse materials, including metals, metal oxides, metal nitrides, metal sulfides, and several inorganic-organic hybrids. However, their high flammability poses a significant drawback, resulting in high risks when handling these compounds and necessitating stringent safety regulations to mitigate their hazardous nature in the event of an accident. Therefore, it is highly desirable to replace these compounds with those that do not exhibit this drawback. Furthermore, thermal stability is an issue, particularly in the case of TMI, which results in a narrow ALD window and a maximum deposition temperature of 250°C. Additionally, TMI is a solid at room temperature, leading to fluctuations in evaporation rates.

[0007] Furthermore, metal amidine complexes (AMDs) are known as precursors for ALD applications. WO2004 / 046417 discloses the use of volatile metal amidine complexes in ALD applications involving a wide variety of metals, wherein the amidine ligand can be substituted with a wide variety of substituents, such as H, alkyl, aryl, alkynyl, etc. Examples disclose complexes with various transition metals and with main group metals Bi and Sr, wherein the amidine ligand is substituted with isopropyl, sec-butyl, and / or tert-butyl. This document suggests using longer alkyl chains and / or alkyl chains having more than one stereoisomer as substituents on the amidine group to lower the melting point.

[0008] GB2295392 A1 discloses a metal amidine complex ML3, wherein M = Al, Ga, or In, and L is an amidine ligand substituted with a substituent such as H, alkyl, haloalkyl, cycloalkyl, phenyl, etc. These complexes are disclosed for use in CVD. Examples only disclose complexes in which the N atom of the amidine ligand is substituted with a phenyl group. As can be seen from the TGA curves, these complexes are not volatile, as evidenced by their high TGA content at around 400°C. 50% Temperature-proven, and not thermally stable, as indicated by a high residual mass exceeding 10%, which can be explained by partial decomposition that may have occurred during or before evaporation.

[0009] EP4134372 discloses metal amidine complexes, wherein the amidine ligand is C 1-5 Alkyl substitution, wherein at least one H atom of the substituent is replaced by F. By using fluorinated ligands, complexes with high vapor pressures and low melting points are obtained. However, due to the toxicity of fluorinated hydrocarbons and their harmful environmental effects, it is desirable to avoid the use of fluorinated compounds. A further disadvantage of fluorinated compounds is that fluorine is generally known to be incorporated into thin films, which drastically alters the properties of the film.

[0010] US2016 / 0017485 discloses indium-tris(N,N'-diisopropylacetamidine) as a precursor for indium sulfide ALD. However, no melting point was observed for this precursor at temperatures as high as 320°C, where the material begins to decompose, meaning it is impossible to operate the precursor in liquid form.

[0011] Furthermore, indium-tris(N,N'-diisopropylmethylammonium) and indium-tris(N,N'-diisopropylethylammonium) as precursors for ALD are disclosed in various scientific publications (e.g., SB Kim et al., Chem. Eur. J. 2018, 24, 9525-9529 and further publications), and they show greater stability than TMI. Although indium-tris(N,N'-diisopropylmethylammonium) enables ALD of indium oxide to use H2O as a co-reactant on the surface in a temperature range of 150-275 °C, it has the disadvantages of low volatility and a high melting point of 270 °C compared to TMI. As mentioned above, indium-tris(N,N'-diisopropylethylammonium) has a considerably high and narrower ALD window of 225-300 °C in similar reactions with H2O, and lacks a melting point where decomposition does not occur.

[0012] US2023 / 0167548 describes gallium-tris(N,N'-diisopropylamidine) complexes as precursors for ALD applications. Aluminum-tris(N,N'-diisopropylacetamidine) is known as a precursor for ALD applications from AL Brazeau, Inorg. Chem. 2006, 45, 2276-2281. As can be seen from thermogravimetric analysis, this aluminum complex does not exhibit clean evaporation without decomposition.

[0013] In methods for forming thin films by vaporization of compounds (e.g., CVD or ALD methods), the compounds used as film-forming precursors (reactants) need to possess the following important properties: high vapor pressure; low melting point, and preferably being liquid at room temperature; high thermal stability; and the ability to produce high-quality films with high productivity, i.e., high reactivity with the surface, co-reactants, and deposited material, and a clean reaction, i.e., the reaction produces virtually no undesirable byproducts on the surface. As mentioned above, there is still room for improvement regarding prior art amidine compounds. Therefore, the object of the present invention is to provide new compounds that, compared with prior art amidine compounds, have high vapor pressure, low melting point, and, when used as film-forming raw materials, can each produce high-quality films with high productivity.

[0014] Surprisingly, it was found that changing the alkyl substituent on the amidine ligand in the metal amidine complex significantly reduces the melting and evaporation temperatures of the resulting metal compounds compared to known metal complexes in the prior art. These compounds also possess suitable thermal stability and volatility, and can be used in CVD or ALD processes to form metal-containing films. Therefore, such compounds are the object of this invention. Summary of the Invention

[0015] The disclosed and claimed subject matter relates to compounds of formula (1): Equation (1) The symbols used are as follows: M is Al, Ga, or In; R N1 R N2 Each time it appears, it is either the same or different alkyl group having 1, 2 or 3 carbon atoms; R C Each occurrence may be the same or different of H, D, methyl, or ethyl; The condition is that when M is In or Ga, the substituent R in the same amidine ligand binds to... N1 and R N2 Not simultaneously isopropyl (iPr); And the condition is that when M is Al and R CWhen the methyl or ethyl group is involved, the substituent R in the same amidine ligand... N1 and R N2 It is not simultaneously isopropyl (iPr).

[0016] Each group [R] in the compound of formula (1) N1 NC(R C )-NR N2 ] - It is called a "ligand" or "amidinyl ligand".

[0017] The disclosed and claimed subjects further include compositions and formulations containing compounds of formula (1), methods of using compounds of formula (1) as precursors for depositing metal-containing films, and metal-containing films derived from compounds of formula (1).

[0018] Detailed description All references cited herein (including publications, patent applications and patents) are incorporated herein by reference as if each reference were individually and explicitly indicated to be incorporated herein by reference and listed in full.

[0019] In describing the disclosed and claimed subject matter (particularly in the context of the following claims), the terms “a,” “an,” and “the,” and similar designations, should be interpreted as encompassing both singular and plural forms, unless otherwise stated herein or the context explicitly contradicts this. The terms “comprising,” “having,” “including,” and “containing” should be interpreted as open-ended terms (i.e., meaning “including but not limited to”), unless otherwise stated. The enumeration of numerical ranges herein is intended merely as a way of abbreviating each individual numerical value falling within that range, unless otherwise stated herein, and each individual numerical value is incorporated into the specification as if it were separately enumerated herein. All methods described herein may be performed in any suitable order, unless otherwise stated herein or the context explicitly contradicts this. The use of any and all instances or exemplary language (e.g., “such as”) provided herein is intended only to better elucidate the disclosed and claimed subject matter and, unless otherwise required, does not constitute a limitation on the scope of the disclosed and claimed subject matter. No language in the specification should be construed as indicating that any unclaimed element is necessary for practicing the disclosed and claimed subject matter. The terms “comprising” or “including” used in the specification and claims include the narrower terms “consistent with” and “comprises from”.

[0020] Implementations of the disclosed and claimed subject matter have been described herein, including the best mode for implementing the disclosed and claimed subject matter. Variations of these examples may become apparent to those skilled in the art upon reading the foregoing description. The inventors expect those skilled in the art to adopt these variations where appropriate, and the inventors intend for the disclosed and claimed subject matter to be practiced in ways other than those specifically described herein. Therefore, the disclosed and claimed subject matter includes all modifications and equivalents of the subject matter recited in the appended claims, where permitted by applicable law. Furthermore, unless otherwise stated herein or the context clearly contradicts, the disclosed and claimed subject matter encompasses any combination of the foregoing elements in all possible variations.

[0021] When describing the use of compounds according to the invention in CVD or ALD deposition techniques, the compounds are also referred to as “precursors” or “reactants”.

[0022] For ease of reference, "microelectronic device" or "semiconductor device" refers to a semiconductor wafer having manufactured integrated circuits, memory, and other electronic structures thereon, as well as flat panel displays, phase-change memory devices, solar panels, and other products manufactured for use in microelectronic, integrated circuit, or computer chip applications, including solar substrates, photovoltaic devices, and microelectromechanical systems (MEMS). Solar substrates include, but are not limited to, silicon, amorphous silicon, polycrystalline silicon, monocrystalline silicon, CdTe, copper indium selenide, copper indium sulfide, and gallium-on-gallium arsenide. Solar substrates may be doped or undoped. It should be understood that the terms "microelectronic device" or "semiconductor device" are not intended to be limited in any way, but rather to include any substrate that will ultimately become a microelectronic device or microelectronic assembly.

[0023] As defined herein, the term "barrier material" refers to any material in the art used to seal metal wires (e.g., copper interconnects) to minimize the diffusion of said metal (e.g., copper) into the dielectric material. Preferred barrier layer materials include tantalum, titanium, ruthenium, hafnium, and other refractory metals and their nitrides and silicides.

[0024] Unless otherwise stated, "alkyl" refers to a hydrocarbon group that can be straight-chain (e.g., methyl, ethyl, n-propyl) or branched (e.g., isopropyl).

[0025] "Substantially free of" is defined herein as less than 0.001% by weight. "Substantially free of" also includes 0.000% by weight. The term "free of" refers to 0.000% by weight. As used herein, "about" or "approximately" is intended to correspond to within ±5% of the stated value.

[0026] In all such compositions, where specific components of the composition are discussed with reference to a range including a zero lower limit of weight percentage (or “weight%” or “wt.%”), it should be understood that such components may or may not be present in various specific embodiments of the composition, and where such components are present, their concentration may be as low as 0.001% by weight based on the total weight of the composition in which such components are used. All percentages of components are weight percentages and are based on the total weight of the composition, i.e., 100%.

[0027] Furthermore, when the compositions described herein are referred to as % by weight or wt.%, it should be understood that in any case, the total weight percentage of all components (including non-essential components, such as impurities) does not exceed 100% by weight. In compositions “consisting primarily of the said components,” such components may total 100% by weight of the composition or may total less than 100% by weight. In cases where the total component percentage is less than 100% by weight, such compositions may contain small amounts of non-essential contaminants or impurities. For example, in one such embodiment, the formulation may contain 2% by weight or less of impurities. In another embodiment, the formulation may contain 1% by weight or less of impurities. In a further embodiment, the formulation may contain 0.05% by weight or less of impurities. In other such embodiments, the components may form at least 90% by weight, more preferably at least 95% by weight, more preferably at least 99% by weight, more preferably at least 99.5% by weight, and most preferably at least 99.9% by weight, and may include other components that do not or do not significantly affect the deposition process. Otherwise, if there are no significant non-essential impurity components, it should be understood that the composition of all essential components substantially totals 100% by weight.

[0028] Any reference to “one or more” or “at least one” includes “two or more” and “three or more”, etc.

[0029] The headings used in this article are not intended to be restrictive; rather, they are included for organizational purposes only.

[0030] In a preferred embodiment of the invention, M is indium or aluminum. In a particularly preferred embodiment, M is indium.

[0031] In a further preferred embodiment of the invention, the three amidine ligands in the compound of formula (1) are identical. Therefore, it is preferred that all groups R N1 Same, all groups R N2 The same, and all groups R C same.

[0032] In one embodiment of the invention, when M is Al, the substituent R bound in the same amidine ligand N1 and RN2 It is not simultaneously isopropyl (iPr).

[0033] Therefore, R N1 R N2 and R c Suitable combinations are compounds 1 to 82 in Table 1. Preferred compounds are 1 to 55 in Table 1, i.e., In or Al compounds, and particularly preferred compounds are 1 to 27 in Table 1, i.e., In compounds.

[0034] Table 1:

[0035] In a further preferred embodiment of the invention, R in each ligand N1 R N2 and R C The total number of carbon atoms is 2 to 6, more preferably 3 to 6, and even more preferably 4, 5 or 6.

[0036] In a further preferred embodiment of the invention, R C It is H or methyl, with R being particularly preferred. C It's H.

[0037] In one embodiment of the present invention, R N1 and R N2 They are the same. In a further preferred embodiment of the invention, R N1 and R N2 They are different from each other.

[0038] Preferred embodiments of the invention are compounds 5, 6, 7, 8, 11, 14, and 23 wherein M = indium, compounds 32, 33, 34, 35, 37, 39, 42, and 51 wherein M = aluminum, and compounds 60, 61, 62, 63, 66, 69, and 78 wherein M = gallium. Preferably, compounds 5, 6, 7, 8, 11, 14, and 23 wherein M = indium and compounds 32, 33, 34, 35, 37, 39, 42, and 51 wherein M = aluminum are preferred, and even more preferably, compounds 5, 6, 7, 8, 11, 14, and 23 wherein M = indium are preferred. Particularly preferred are compound 5 wherein M = indium and compound 32 wherein M = aluminum, i.e., compounds wherein M = indium or aluminum, R... C = H and R N1 = R N2 =Ethyl compounds, and compound 8 wherein M = indium and compound 35 wherein M = aluminum, i.e., wherein M = indium or aluminum, RC = H and R N1 = R N2 =A compound with n-propyl groups. A further preferred embodiment of the invention is wherein M = aluminum, R = n-propyl groups. C = H and R N1 = R N2 =Isopropyl compound 37.

[0039] Preferably, the compound of formula (1) or the preferred embodiment is substantially free of impurities. This specifically refers to metallic impurities, organic byproducts, and halogen impurities. The content of each impurity metallic element is preferably 10 ppm or less, more preferably 1 ppm or less, and their total content is preferably 50 ppm or less, more preferably 10 ppm or less. The total content of impurity halogens is preferably 100 ppm or less, more preferably 10 ppm or less, and most preferably 1 ppm or less.

[0040] Compounds of formula (1) and preferred embodiments can be synthesized by reacting a suitable metal precursor MX3 (where M is Al, Ga, or In, and X is a counter anion, such as a halide (F, Cl, Br, I, preferably Cl), trifluoromethanesulfonate, or p-toluenesulfonate) with a desired amidine salt (such as LiAMD, NaAMD, or KAMD, preferably LiAMD), where AMD represents an amidine group. The amidine salt can be prepared in situ from the corresponding amidine by deprotonation in a solvent, preferably a polar or nonpolar aprotic solvent, such as THF dioxane, diethyl ether, methyl tert-butyl ether, dibutyl ether, hexane, pentane, or toluene, or mixtures thereof. Examples of suitable bases for deprotonation are alkyllithium, such as butyllithium or hexyllithium; alkali metal hydrides, such as LiH, NaH, or KH; or hexamethyldisilazane salts, such as LiHMDS, NaHMDS, or KHMDS.

[0041] Therefore, the present invention further relates to a method for preparing a compound of formula (1) or a preferred embodiment, wherein the compound MX3 (where M = Al, Ga or In, and X is a counterion, preferably F, Cl, Br, I, trifluoromethanesulfonate or p-toluenesulfonate, particularly preferably Cl) reacts with an amidine salt, preferably Li, Na or K salt, particularly preferably Li salt.

[0042] How to use The disclosed compounds can be used as precursors (reactants) for depositing metal-containing films using any chemical vapor deposition process known to those skilled in the art. Precursors for forming thin films, also referred to as "thin film formation precursors," include compounds according to the invention and optionally further compounds, depending on the manufacturing process to which the precursor is applied. For example, when producing a thin film containing only metal atoms M as metals, the thin film formation precursors of the invention do not contain metal compounds other than those represented by general formula (1). Meanwhile, when producing a thin film containing two or more metals, the thin film formation precursors of the invention may contain compounds containing the desired metals other than the phase of the compound represented by general formula (1). The thin film formation precursors of the invention may further contain organic solvents. As mentioned above, the physical properties of the compounds represented by general formula (1) are suitable for use as precursors in CVD methods; therefore, the thin film formation precursors of the invention can be used as CVD precursors. In particular, the thin film formation precursors of the invention are particularly suitable for ALD methods because the compounds represented by general formula (1) exhibit self-limiting reaction behavior at the surface, i.e., they do not react with adsorbed surface precursor substances.

[0043] As used herein, the term “chemical vapor deposition process” (CVD) refers to any process in which the substrate is exposed to one or more volatile precursors that react and / or decompose on the substrate surface to produce the desired deposition. As used herein, the term “atomic layer deposition process” (ALD) refers to a self-limiting (e.g., the amount of film material deposited is constant in each reaction cycle), sequential surface chemistry process for depositing a film of material onto a substrate of varying compositions. Although precursors, reagents, and co-reagents used herein may sometimes be described as “gaseous,” it should be understood that precursors may be liquid or solid at room temperature and / or elevated temperatures and may be delivered to the reactor by direct vaporization, bubbling, or sublimation, with or without an inert gas. In some cases, vaporized precursors may pass through a plasma generator. The term “reactor” as used herein includes, but is not limited to, reaction chambers (reaction vessels, deposition chambers).

[0044] The chemical vapor deposition processes in which the disclosed and claimed compounds can be used as precursors include, but are not limited to, those processes used for fabricating semiconductor-type microelectronic devices, such as ALD, CVD, pulsed CVD, plasma-enhanced ALD (PEALD), and / or plasma-enhanced CVD (PECVD). Examples of deposition processes suitable for the methods disclosed herein include, but are not limited to, cyclic CVD (CCVD), MOCVD (metal-organic CVD), thermochemical vapor deposition, plasma-enhanced chemical vapor deposition (“PECVD”), high-density PECVD, photon-assisted CVD, plasma-photon-assisted CVD (“PPECVD”), low-temperature chemical vapor deposition, chemical-assisted vapor deposition, hot-filament chemical vapor deposition, CVD with liquid polymer precursors, supercritical fluid deposition, low-energy CVD (LECVD), roll-to-roll ALD, space ALD, and atmospheric pressure ALD. In some embodiments, the metal-containing film is deposited via atomic layer deposition (ALD), plasma-enhanced ALD (PEALD), or plasma-enhanced cyclic CVD (PECCVD) processes.

[0045] In one embodiment, a metal-containing film is deposited using an ALD process. In another embodiment, a metal-containing film is deposited using a CCVD process. In a further embodiment, a thermal CVD process is used to deposit the metal-containing film.

[0046] There are no particular limitations on suitable substrates on which the disclosed and claimed precursors can be deposited, and these vary depending on the intended end use. For example, the substrate can be selected from oxides, such as HfO2-based materials, TiO2-based materials, ZrO2-based materials, rare earth oxide-based materials, ternary oxide-based materials, etc., or nitride-based materials. Other substrates may include solid substrates, such as metal substrates (e.g., Au, Pd, Rh, Ru, W, Al, Ni, Ti, Co, Pt), metal silicide-containing substrates (e.g., TiSi2, CoSi2, and NiSi2), metal nitride-containing substrates (e.g., TaN, TiN, WN, TaCN, TiCN, TaSiN, and TiSiN), semiconductor materials (e.g., Si, SiGe, GaAs, InP, diamond, GaN, and SiC), insulators (e.g., SiO2, Si3N4, SiON, HfO2, Ta2O5, ZrO2, TiO2, Al2O3, and barium strontium titanate), and combinations thereof. Preferred substrates include TiN, Ru, and Si type substrates.

[0047] In such deposition methods and processes, co-reactants, such as oxidants, are typically used. "Oxidant" in this application is understood to refer to a compound that transfers oxygen to the metal-containing film. Oxidants are typically introduced in gaseous form. Examples of suitable oxidants include, but are not limited to, oxygen, water vapor, ozone, oxygen plasma, or mixtures thereof.

[0048] Further possible co-reactants are reducing agents such as H2, H2 plasma, hydrazine, or aminoborane; nitrogen-containing co-reactants such as hydrazine, NH3, N2, or N2 plasma; sulfur-containing co-reactants such as H2S or elemental sulfur; or peroxides such as H2O2 or HOOtBu.

[0049] Deposition methods and processes may also involve a purging step, typically accomplished using one or more purging gases. The purging gas used to purge unconsumed reactants and / or reaction byproducts is an inert gas that does not react with the precursors and the formed film. Exemplary purging gases include, but are not limited to, argon (Ar), nitrogen (N2), helium (He), neon (Ne), and mixtures thereof. For example, a purging gas, such as Ar, is supplied to the reactor at a flow rate ranging from about 10 to about 2000 sccm for about 0.1 to 10000 seconds to purge unreacted material and any byproducts that may remain in the reactor.

[0050] The deposition methods and processes require the application of energy to at least one of the precursors, co-reactants, or combinations thereof according to the invention to induce a reaction and form a metal-containing film or coating on a substrate. This energy can be provided by, but is not limited to, temperature (thermally induced), plasma, pulsed plasma, helical wave plasma, high-density plasma, inductively coupled plasma, X-ray, electron beam, photon, remote plasma methods, and combinations thereof. In some methods, a secondary RF frequency source can be used to modify the plasma characteristics at the substrate surface. When using plasma, the plasma generation process can include a direct plasma generation process (where plasma is generated directly in the reactor), or alternatively, a remote plasma generation process (where plasma is generated outside the reactor and supplied to the reactor).

[0051] When used in such deposition methods and processes, suitable precursors, such as the compounds of the present invention, can be delivered to the reaction chamber, such as a CVD or ALD reactor, in a variety of ways. A preferred method of delivering the precursor to the reaction chamber is by vaporization of the precursor, for example by vacuum-driven thermal vaporization or by active vaporization using a carrier gas. In other cases, liquid delivery systems or combined liquid delivery and rapid vaporization process units can be employed to enable the metered delivery of low-volatility materials, resulting in repeatable delivery and deposition without thermal decomposition of the precursor. The precursor compositions described herein can be effectively used as reagents by direct liquid injection (DLI) or by vacuum-driven evaporation to provide a vapor stream of these metal precursors to the ALD or CVD reactor. Vacuum-driven vaporization is a preferred method of delivering precursors according to the present invention.

[0052] When used in these deposition methods and processes, the disclosed and claimed compounds may include hydrocarbon solvents, which are particularly desirable due to their ability to be dried to sub-ppm water content. Exemplary hydrocarbon solvents that can be used in precursors include, but are not limited to, toluene, mesitylene, cumene (isopropylbenzene), p-cymene (4-isopropyltoluene), 1,3-diisopropylbenzene, octane, dodecane, 1,2,4-trimethylcyclohexane, n-butylcyclohexane, and decahydronaphthalene (naphthalene). The disclosed and claimed compounds may also be stored and used in stainless steel containers. In some embodiments, the hydrocarbon solvent is a high-boiling solvent or has a boiling point of 100°C or higher. The disclosed and claimed compounds may also be mixed with other suitable metal compounds (which may be used as precursors), and the mixture is used to simultaneously deliver two metals for the growth of binary metal-containing films.

[0053] A stream of argon and / or other gases may be used as a carrier gas to help deliver vapor containing at least one of the disclosed and claimed precursors to the reaction chamber during precursor pulses. When delivering the precursor, the process pressure in the reaction chamber is between 1 and 50 Torr, preferably between 5 and 20 Torr.

[0054] Substrate temperature can be a significant process variable when depositing high-quality metal-containing films. Typical substrate temperatures range from approximately 100°C to approximately 550°C. Higher temperatures can promote higher film growth rates but may result in bulk CVD rather than ALD. Furthermore, at higher substrate temperatures, there is a risk of precursor desorption from the substrate, leading to a lower growth rate. If the substrate temperature is not high enough, it may be too low to allow the precursor to react sufficiently with the surface, also resulting in a lower growth rate, and / or the precursor may condense on the surface, leading to an increased growth rate.

[0055] In view of the foregoing, those skilled in the art will recognize that the disclosed and claimed subject matter further includes using the disclosed and claimed compounds as precursors in chemical vapor deposition (CVD) processes.

[0056] In one embodiment, the disclosed and claimed subject matter includes a method for forming a metal-containing film on at least one surface of a substrate, wherein the metal is Al, Ga, or In, the method comprising the following steps: (a) Providing at least one surface of the substrate in the reaction vessel; and (b) Using at least one compound of formula (1) or a preferred embodiment as a precursor of a metal source compound for a deposition process, a metal-containing film is formed on at least one surface by at least one deposition process selected from chemical vapor deposition (CVD) and atomic layer deposition (ALD).

[0057] In a further aspect of this embodiment, the method includes introducing at least one co-reactant into a reaction vessel. The co-reactant is a reactant used for depositing a metal-containing film, in addition to the precursor of the invention. In a further aspect of this embodiment, the method includes introducing at least one co-reactant into a reaction vessel, wherein the at least one co-reactant is selected from water, oxygen (O2), oxygen plasma, ozone (O3), NO, N2O, NO2, CO, CO2, and combinations thereof. These co-reactants are typically used to form metal oxide thin films. In another aspect of this embodiment, the method includes introducing at least one co-reactant into a reaction vessel, wherein the at least one co-reactant is selected from ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, and combinations thereof. These co-reactants are typically used to form metal nitride thin films, but if the metal is indium, ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, ammonia plasma, and combinations thereof can also be used to form a metal film. In another aspect of this embodiment, the method includes introducing at least one co-reactant into a reaction vessel, wherein the at least one co-reactant is selected from hydrogen, hydrogen plasma, mixtures of hydrogen and helium, mixtures of hydrogen and argon, hydrogen / helium plasma, hydrogen / argon plasma, boron-containing compounds, silicon-containing compounds, and combinations thereof. These co-reactants are typically used to form metal films, i.e., to form elemental metals.

[0058] In one embodiment, the disclosed and claimed subject matter includes a method for forming a metal-containing film by an atomic layer deposition (ALD) process or an ALD-like process, wherein the metal is Al, Ga, or In, the method comprising the following steps: (a) Providing a substrate in the reaction vessel; (b) Introducing one or more compounds of formula (1) or preferred embodiments as precursors into the reaction vessel; (c) Purging procedure, especially purging the reaction vessel with a first purging gas; (d) Introduce co-reactants into the reaction vessel; (e) Purging steps, particularly purging the reaction vessel with a second purging gas; (f) Repeat steps (b) to (e) sequentially until a metal-containing film of the desired thickness is obtained.

[0059] Depending on the desired composition of the resulting metal-containing thin film, steps (b), (c), (d), and (e) can also be repeated with the second co-reactant in step (d) and optionally a third or more co-reactants, as well as a purging step with a third purging gas and optionally a fourth or more purging gases.

[0060] Furthermore, in step (b), two or more precursors may be introduced, wherein at least one precursor is a compound of formula (1) or a preferred embodiment. These two or more precursors may be introduced as a mixture from the same container, or they may be introduced from different containers.

[0061] Furthermore, two or more co-reactants may be introduced in step (d). These two or more co-reactants may be introduced as a mixture from the same source container, or they may be introduced from different containers.

[0062] In a further aspect of this embodiment, the co-reactant is one or more oxygen-containing co-reactants selected from water, O2, oxygen plasma, O3, NO, N2O, NO2, CO, CO2, and combinations thereof. In another aspect of this embodiment, the co-reactant is one or more nitrogen-containing co-reactants selected from ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, and mixtures thereof. In another aspect of this embodiment, the co-reactant is selected from hydrogen, hydrogen plasma, mixtures of hydrogen and helium, mixtures of hydrogen and argon, hydrogen / helium plasma, hydrogen / argon plasma, boron-containing compounds, silicon-containing compounds, and combinations thereof. In a further aspect of this embodiment, the first and second purge gases in the method are one or more independently selected from argon, nitrogen, helium, neon, and combinations thereof. Additionally or alternatively, a vacuum may be applied to one or more purge steps. In a further aspect of this embodiment, the method further includes applying energy to at least one of the precursor, co-reactant, substrate, and combinations thereof, wherein the energy is one or more of heat, plasma, pulsed plasma, helical wave plasma, high-density plasma, inductively coupled plasma, capacitively coupled plasma, X-ray, electron beam, photon, remote plasma methods, and combinations thereof. In a preferred aspect of this embodiment, step (b) of the method includes introducing the precursor into the reaction vessel using thermal energy and vacuum. In a further aspect of this embodiment, step (b) of the method further includes introducing the precursor into the reaction vessel using a carrier gas flow to deliver the vapor of the precursor into the reaction vessel. In a further aspect of this embodiment, step (b) of the method further includes using a solvent medium comprising one or more of toluene, mesitylene, isopropylbenzene, 4-isopropyltoluene, 1,3-diisopropylbenzene, octane, dodecane, 1,2,4-trimethylcyclohexane, n-butylcyclohexane, and decahydronaphthalene, and combinations thereof.

[0063] The shape of the substrate is not particularly limited and can be, for example, plate-like, spherical, fibrous, or scaly. The surface of the substrate can be planar or can have a three-dimensional structure, such as a trench structure.

[0064] Furthermore, examples of the aforementioned production conditions include reaction temperature (substrate temperature), reaction pressure, and deposition rate. The reaction temperature is preferably from room temperature to 500°C, more preferably from 100°C to 300°C. Additionally, in the case of thermal CVD or optical CVD, the reaction pressure is preferably from 10 Pa to atmospheric pressure, and in the case of using plasma, the reaction pressure is preferably from 10 Pa to 2,000 Pa. For ALD, when this step is performed, the system pressure (in the film formation chamber) is preferably from 1 Pa to 10,000 Pa, more preferably from 10 Pa to 1,000 Pa.

[0065] Furthermore, the deposition rate can be controlled by the precursor supply conditions (vaporization temperature and vaporization pressure), reaction temperature, and reaction pressure. When the deposition rate is high, the properties of the resulting film may deteriorate. When the deposition rate is low, productivity may be problematic. Therefore, for chemical CVD processes, the deposition rate is preferably from 0.01 nm / min to 100 nm / min, more preferably from 1 nm / min to 50 nm / min. Additionally, in the case of the ALD method, the desired film thickness can be obtained by controlling the deposition rate through the number of cycles. In the ALD process, typical deposition rates are from 0.01 nm / cycle to 0.2 nm / cycle, more typically from 0.05 nm / cycle to 1.3 nm / cycle. Furthermore, as the above production conditions, the temperature and pressure at which the film formation precursor is vaporized to obtain the precursor gas are given. The step of vaporizing the film formation precursor to obtain the precursor gas can be carried out in a precursor container or an evaporation chamber. In any case, it is preferred that the film formation precursor of the present invention is vaporized at a temperature between 0°C and 150°C. In addition, when the membrane formation precursor is vaporized in a precursor container or vaporization chamber to obtain a precursor gas, the pressure in the precursor container and the pressure in the vaporization chamber are preferably from 1 Pa to 10,000 Pa.

[0066] Furthermore, in the method for producing the thin film of the present invention, after film deposition, annealing can be performed under an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere to obtain more satisfactory electrical properties. The annealing temperature is from 200°C to 1000°C, preferably from 250°C to 500°C.

[0067] Brief description of the attached figures Figure 1 TGA curves of various indium compounds according to the present invention and comparative indium compounds are shown.

[0068] Figure 2 TGA curves of various aluminum compounds according to the present invention and comparative aluminum compounds are shown.

[0069] Figure 3 The results of the thermal decomposition study of In(Et2-fAMD)3 on SiO2 and TiN are shown.

[0070] Figure 4 The saturation study of In(Et2-fAMD)3 on SiO2 with O3 as a co-reactant is shown at a substrate temperature of 300 °C.

[0071] Figure 5SEM micrographs of the top, middle, and bottom locations of a Si (natural oxide) trench substrate with an aspect ratio of 17:1, coated with indium oxide of In(Et2-fAMD)3 and O3 at 300 °C, are shown, along with estimated film thicknesses (from SEM) and calculated step coverage values ​​at the specified locations. Detailed Implementation

[0072] Example Reference will now be made to more specific embodiments of this disclosure and experimental results supporting these embodiments. The examples given below are intended to illustrate the disclosed subject matter more fully and should not be construed as limiting the disclosed subject matter in any way.

[0073] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed subject matter and the specific embodiments provided herein without departing from the spirit or scope of the disclosed subject matter. Therefore, the disclosed subject matter (including the description provided by the following embodiments) is intended to cover modifications and variations of the disclosed subject matter that fall within the scope of any claims and their equivalents.

[0074] Materials and methods: Unless otherwise stated, all solvents and starting materials were purchased from Sigma-Aldrich.

[0075] General synthesis procedure: In a Schlenk flask, the corresponding amidine (AMDH) (3 eq) of the complexes shown below was dissolved in THF (27 eq) and cooled to -78 °C. 1.6 M of n-butyllithium (nBuLi) in hexane (3 eq) was added dropwise to the solution. The mixture was allowed to warm to room temperature and stirred for 2 hours. The mixture was cooled to 0 °C and slowly transferred through a sleeve to a cold solution of the corresponding metal chloride (InCl3, GaCl3, or AlCl3) in THF (18 eq) at 0 °C. After the addition, the reaction mixture was stirred overnight at room temperature. The solvent was removed under reduced pressure, and the crude mixture was extracted with toluene. The suspension was filtered, and the solvent in the filtrate was removed under reduced pressure. The crude product was sublimated under the given conditions to obtain the spectroscopically pure complexes. In the following text, fAMD represents formamidinium, and MeAMD represents acetamidine. The amidines used are known in the literature.

[0076] Example 1: In(Et2-fAMD)3 M = In, R N1 = R N2 =Ethyl and R C = compounds of H.

[0077] 1H NMR (500 MHz, C6D6) δ 7.37 (s, 3H), 3.25 (q, J = 7.2 Hz, 12H), 1.17(t, J = 7.2 Hz, 18H). TGA: T 1% = 111 ℃, T 50% = 193 ℃, m Rest = 1.5% The vapor pressure of TGA: Lg(p[Pa]) = -2822.2 1 / T[K] + 9.6281  T 1托 = 103 ℃ DSC: T 熔点 = 38.0 ℃ Example 2: In(nPr2-fAMD)3 M = In, R N1 = R N2 =n-propyl and R C = compounds of H.

[0078] 1 H NMR (500 MHz, C6D6) δ 7.38 (s, 3H), 3.19 (t, J = 6.8 Hz, 12H), 1.56 (q, J = 7.1 Hz, 12H), 0.95 (t, J = 7.4 Hz, 18H). TGA: T 1% = 102 ℃, T 50% = 233 ℃, m Rest = 1.0% The vapor pressure of TGA: Lg(p[Pa]) = -3628.2 1 / T[K] + 10.825  T 1托 = 144 ℃ DSC: T 熔点 <-50 ℃ Example 3: In(Et-Me-MeAMD)3 M = In, R N1 =Ethyl, R N2 =Methyl and R C =A compound containing methyl groups.

[0079] 1H NMR (500 MHz, C6D6) δ 3.31 – 3.19 (m, 6H), 3.05 – 2.92 (m, 9H), 1.57 – 1.39 (m, 9H), 1.34 – 1.18 (m, 9H). TGA: T 1% = 137 ℃, T 50% = 216 ℃, m Rest = 4.4% DSC: T 熔点 = 110 ℃ Example 4: In(Me2-MeAMD)3 M = In and R N1 = R N2 = R C =A compound containing methyl groups.

[0080] 1 H NMR (500 MHz, C6D6) δ 3.01 (s, 18H), 1.42 (s, 9H). TGA: T 1% = 115 ℃, T 50% = 215 ℃, m Rest = 12.9% DSC: T 熔点 = 183 ℃ Example 5: Al(Et2-fAMD)3 M = Al and R N1 = R N2 =Ethyl and R C = compounds of H.

[0081] 1 H NMR (500 MHz, C6D6) δ 7.33 (s, 3H), 3.14 (q, J = 7.1 Hz, 12H), 1.15(t, J = 7.2 Hz, 18H). TGA: T 1% = 98 ℃, T 50% = 179 ℃, m Rest = 0.2% DSC: T 熔点 = Not observed Example 6: Al(nPr2-fAMD)3 M = Al and R N1 = RN2 =n-propyl and R C = compounds of H.

[0082] 1 H NMR (500 MHz, C6D6) δ 7.35 (s, 3H), 3.06 (t, J = 7.1 Hz, 12H), 1.54 (q, J = 7.3 Hz, 12H), 0.94 (t, J = 7.4 Hz, 18H). TGA: T 1% = 130 ℃, T 50% = 231 ℃, m Rest = 0.2% DSC: T 熔点 =< -50 ℃ Example 7: Al(iPr2-fAMD)3 M = Al, R N1 = R N2 =Isopropyl and R C = compounds of H.

[0083] 1 H NMR (500 MHz, C6D6) δ 7.58 (s, 3H), 3.47 (hept, J = 6.5 Hz, 6H), 1.21 (d, J = 6.5 Hz, 36H). TGA: T 1% = 152 ℃, T 50% = 235 ℃, m Rest = 0.4% DSC: T 熔点 = 132 ℃ Comparative Example 1: In(iPr2-fAMD)3 M = In, R N1 = R N2 =Isopropyl and R C = compounds of H.

[0084] 1 H NMR (500 MHz, C6D6) δ 7.44 (s, 3H), 3.53 (hept, J = 6.4 Hz, 6H), 1.24 (d, J = 6.4 Hz, 36H). TGA: T 1% = 159 ℃, T 50% = 236 ℃, m Rest= 0.5% DSC: T 熔点 = 260 ℃ Analysis through TGA TGA curves were determined for the indium precursors of Examples 1-4 and Comparative Example 1, and the aluminum precursors of Examples 5-7. For the TGA experiments, the sample mass for each compound was 10 mg. The TGA curves for the indium complexes are shown in [Figure number missing]. Figure 1 The TGA curves of the aluminum complex are shown below. Figure 2 .

[0085] Discussion of Results The compound of Comparative Example 1 is known, for example from SB Kim et al., Chem. Eur. J. 2018, 24, 9525-9529. This compound has a melting point of 260 °C. Surprisingly, it was found that by introducing small, unbranched alkyl residues to replace the isopropyl group, the melting point could be significantly reduced to substances with melting points below 40 °C or even liquid at room temperature. Furthermore, TGA experiments showed that the volatility of the precursor was improved compared to In(iPr2-fAMD)3, as indicated by T... 1% and T 50% Value proof (see) Figure 1 (See Table 1). It is particularly advantageous if the compound is liquid at the evaporation temperature, especially at room temperature, because condensation is less likely to occur if any cold spots exist in the precursor delivery system. Furthermore, the handling of compounds that are liquid at room temperature is technically easier, for example, by filling the container to which the precursor is applied.

[0086] Table 1. Amidrine In precursors of Examples 1 to 4 and In (iPr2-fAMD) of Comparative Example 1 at the start of evaporation (T 1% ), 50% mass loss (T) 50% A comparison of melting point and other aspects.

[0087] The properties of the aluminum compounds are summarized in Table 2. All compounds are stable during evaporation and show clean evaporation profiles. Figure 2 Compounds with n-propyl (Example 6) and isopropyl (Example 7) substituents on the N atom exhibit similar volatility. Surprisingly, it was found that by introducing a n-propyl residue instead of an isopropyl residue, the melting point could be significantly lowered, yielding a compound that is liquid at room temperature. Volatility can be further increased when an ethyl substituent is used instead of a propyl substituent on the N atom, as seen from T… 1% and T 50% Value proof ( Figure 2 (and Table 2).

[0088] Table 2. Results obtained using the aluminum amidine precursors of Examples 5 to 7.

[0089] ALD using Indium Oxide Film of In(Et2-fAMD)3 - General Procedure Atomic layer deposition of indium oxide films using the precursors of this invention was demonstrated using an Atomic Premium CN-1 200 mm reactor. The precursor In(Et2-fAMD)3 was supplied from an SS316 ampoule (container) maintained at 88°C (ampoule wall temperature). The precursor vapor was delivered to the reaction chamber using an argon carrier gas flow of 25 sccm. The reaction chamber pressure was 1.2–1.5 Torr. Ozone was used as a co-reagent. Indium oxide films were deposited using silicon with native oxides and a TiN substrate. The thickness of the indium oxide film was measured using X-ray fluorescence (XRF) calibrated by XRR of the deposited indium oxide film.

[0090] Example 7: Precursor thermal decomposition test on Si and TiN wafers In this experiment, In(Et2-fAMD)3 precursor vapor was delivered to the deposition chamber in a pulsed pattern separated by argon purging. The pulse sequence was: 6 s precursor pulse followed by 30 s argon purging. The total number of precursor / Ar purging cycles was 50. Oxidant pulses were not used in this experiment to demonstrate the good thermal stability of the precursor in the absence of an oxidant. Good thermal stability (lack of deposition in the absence of an oxidant) is an important precursor property for atomic layer deposition processes. The wafer temperature varied between 150-400 °C. After the experiment, the indium layer density on the surface was measured by X-ray fluorescence analysis, and as shown... Figure 3 As shown, no increase in indium concentration was observed on silicon and TiN wafers with natural oxides at temperatures up to 400°C, indicating the excellent thermal stability of this precursor in the vapor phase and its potential use in vapor deposition applications.

[0091] Example 8: Precursor saturation behavior during deposition In this experiment, indium oxide films were deposited using an atomic layer deposition method that includes the following steps: a. Provide a Si or SiO2 substrate in the reaction vessel; b. Introduce the (Et2-fAMD)3 precursor into the reaction vessel; c. Purge the reaction vessel with argon gas; d. Introduce ozone into the reaction vessel; e. Purging the reaction vessel with a pump and argon gas; and f. Repeat steps b to e sequentially until an indium-containing film of the desired thickness is obtained.

[0092] The In(Et2-fAMD)3 precursor pulse duration varied from 2 s to 8 s to demonstrate saturation behavior with increasing pulse duration. The Ar purge following the precursor pulse was 30 s, followed by a 2 s ozone pulse, a 30 s pumping step, and a 30 s Ar purge. The ALD cycle number was 50. Figure 4 The study demonstrates excellent saturation behavior of a 6-s pulse of In(Et2-fAMD)3 at 300°C. Saturation behavior is one of the key characteristics of atomic layer deposition processes.

[0093] Example 9: Deposition of indium oxide film on trench substrate (aspect ratio 17:1) In this experiment, indium oxide films were deposited using an atomic layer deposition method that includes the following steps: a. Provide a Si or SiO2 substrate in the reaction vessel; b. Introduce the (Et2-fAMD)3 precursor into the reaction vessel; c. Purge the reaction vessel with argon gas; d. Introduce ozone into the reaction vessel; e. Purging the reaction vessel with a pump and argon gas; and f. Repeat steps b to e sequentially until an indium-containing film of the desired thickness is obtained.

[0094] The In(Et2-fAMD)3 precursor pulse lasts 6 seconds. Following the precursor pulse, there is a 30-second Ar purge, a 2-second ozone pulse, and a 30-second pump followed by a 30-second Ar purge. The ALD cycle count is 260. The wafer temperature is 300°C. Figure 5 A cross-sectional SEM image of an indium oxide film deposited on a structured wafer at 300 °C is shown. Figure 5 The film thickness at the top, middle, and bottom of the trenches on the patterned wafer is shown. TEM reveals a smooth and dense film deposition. Experiments also show only small thickness variations at different sites, indicating good ALD performance. Beyond theoretical limitations, it is believed that step coverage can be further improved through process optimization, such as longer precursor pulses and purge times.

[0095] The foregoing description is primarily for illustrative purposes. Although the disclosed and claimed subject matter has been shown and described with respect to exemplary embodiments thereof, those skilled in the art will understand that various foregoing and other changes, omissions, and additions may be made to its form and details without departing from the spirit and scope of the disclosed and claimed subject matter.

Claims

1. Compounds of formula (1): Equation (1) The symbols used are as follows: M is Al, Ga, or In; R N1 R N2 Each time it appears, it is the same or different alkyl group having 1, 2 or 3 carbon atoms; R C It may be H, D, methyl, or ethyl in each occurrence, either the same or different. The condition is that when M is In or Ga, the substituent R in the same amidine ligand binds to... N1 and R N2 Not simultaneously isopropyl (iPr) group; And the condition is that when M is Al and R C When the methyl or ethyl group is involved, the substituent R in the same amidine ligand... N1 and R N2 It is not simultaneously an isopropyl (iPr) group.

2. The compound according to claim 1, characterized in that... M is indium or aluminum, preferably indium.

3. The compound according to claim 1 or 2, characterized in that... All three amidoyl ligands are identical.

4. The compound according to one or more of claims 1 to 3, characterized in that... R in each ligand N1 R N2 and R C The total number of carbon atoms is between 2 and 6.

5. The compound according to claim 4, characterized in that... R in each ligand N1 R N2 and R C The total number of carbon atoms is 4, 5, or 6.

6. The compound according to one or more of claims 1 to 5, characterized in that... R C For H.

7. The compound according to one or more of claims 1 to 6, wherein the following symbols are applicable: M = In, R N1 = Ethyl, R N2 = Ethyl, R C = H; or M = In, R N1 = Ethyl, R N2 = n-propyl, R C = H; or M = In, R N1 = Ethyl, R N2 = Isopropyl, R C = H; or M = In, R N1 = n-propyl, R N2 = n-propyl, R C = H; or M = In, R N1 = Methyl, R N2 = Ethyl, R C = Methyl; or M = In, R N1 = Ethyl, R N2 = Ethyl, R C = Methyl; or M = In, R N1 = Ethyl, R N2 = Ethyl, R C = Ethyl; or M = Al, R N1 = Ethyl, R N2 = Ethyl, R C = H; or M = Al, R N1 = Ethyl, R N2 = n-propyl, R C = H; or M = Al, R N1 = Ethyl, R N2 = Isopropyl, R C = H; or M = Al, R N1 = n-propyl, R N2 = n-propyl, R C = H; or M = Al, R N1 = Isopropyl, R N2 = Isopropyl, R C = H; or M = Al, R N1 = Methyl, R N2 = Ethyl, R C = Methyl; or M = Al, R N1 = Ethyl, R N2 = Ethyl, R C = Methyl; or M = Al, R N1 = Ethyl, R N2 = Ethyl, R C = Ethyl; or M = Ga, R N1 = Ethyl, R N2 = Ethyl, R C = H; or M = Ga, R N1 = Ethyl, R N2 = n-propyl, R C = H; or M = Ga, R N1 = Ethyl, R N2 = Isopropyl, R C = H; or M = Ga, R N1 = n-propyl, R N2 = n-propyl, R C = H; or M = Ga, R N1 = Methyl, R N2 = Ethyl, R C = Methyl; or M = Ga, R N1 = Ethyl, R N2 = Ethyl, R C = Methyl; or M = Ga, R N1 = Ethyl, R N2 = Ethyl, R C = Ethyl.

8. A method for preparing the compound according to one or more of claims 1 to 7, characterized in that... Compounds of formula MX3 react with amidine salts, where M = Al, Ga, or In, and X = F, Cl, Br, I, trifluoromethanesulfonate, or p-toluenesulfonate.

9. Use of the compound according to one or more of claims 1 to 7 for depositing metal-containing films.

10. A method for forming a metal-containing film on at least one surface of a substrate, wherein the metal is Al, Ga, or In, the method comprising the steps of: (a) Providing at least one surface of the substrate in a reaction vessel; as well as (b) Using at least one compound according to one or more of claims 1 to 7 as a precursor of a metal source compound for a deposition process, a metal-containing film is formed on the at least one surface by a deposition process selected from chemical vapor deposition (CVD) and atomic layer deposition (ALD).

11. The method of claim 10, further comprising introducing at least one co-reactant into the reaction vessel.

12. The method according to claim 11, characterized in that... The co-reactants are selected from water, oxygen, oxygen plasma, ozone, NO, N2O, NO2, CO, CO2, ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, hydrogen, hydrogen plasma, mixtures of hydrogen and helium, mixtures of hydrogen and argon, hydrogen / helium plasma, hydrogen / argon plasma, boron-containing compounds, silicon-containing compounds, and combinations thereof.

13. A method for forming a metal-containing film by atomic layer deposition (ALD) or an ALD-like process, wherein the metal is Al, Ga, or In, the method comprising the following steps: (a) Providing a substrate in the reaction vessel; (b) Introducing one or more of the compounds according to one or more of claims 1 to 7 as precursors into the reaction vessel; (c) A purging step, particularly purging the reaction vessel with a first purging gas; (d) Introduce the co-reactant into the reaction vessel; (e) A purging step, particularly purging the reaction vessel with a second purging gas; (f) Repeat steps (b) through (e) sequentially until the metal-containing film of the desired thickness is obtained.

14. The method according to claim 13, characterized in that... At least one co-reactant in step (d) is selected from water, O2, O3, NO, N2O, NO2, CO, CO2, ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, hydrogen, a mixture of hydrogen and helium, a mixture of hydrogen and argon, hydrogen / helium plasma, boron-containing compounds, silicon-containing compounds and combinations thereof, or plasmas of these co-reactants.

15. The method according to one or more of claims 10 to 14, characterized in that... The compound according to one or more of claims 1 to 7 is introduced into the reaction vessel by vaporization using thermal energy and vacuum.

Images