Precursors for deposition of molybdenum-containing films

Abstract

Molybdenum-containing films are deposited on semiconductor substrates in ALD and CVD processes using the reaction of molybdenum-containing precursors. In some embodiments, the precursors may be used to deposit molybdenum metal films with low incorporation amounts of carbon and nitrogen. In some embodiments, the film is deposited with a fluorine-free precursor in the presence of an exposed silicon-containing layer, but without the use of an etch stop layer. In some embodiments, the precursor is a compound comprising molybdenum, at least one halogen forming a bond with molybdenum, and at least one organic ligand comprising an element selected from the group consisting of N, O, and S, which forms a bond with molybdenum. In another aspect, the precursor is a molybdenum compound having at least one sulfur-containing ligand, and preferably does not have a molybdenum-carbon bond.

Description

This application is a divisional application of the invention patent application with application number 202080020646.X, application date March 6, 2020, and invention name “Precursor for depositing molybdenum-containing films”. Incorporated by Reference

[0001] The PCT application form is filed concurrently with this specification as a part of this application. Each application to which this application claims the benefit or priority as identified in the concurrently filed PCT application form is incorporated herein by reference in its entirety and for all purposes. Technical Field

[0002] The present invention relates to methods for making semiconductor devices. In particular, embodiments of the present invention relate to precursors for depositing molybdenum-containing films in semiconductor processing. Background Art

[0003] In integrated circuit (IC) manufacturing, deposition and etching techniques are used to form patterns of materials, such as for forming metal lines embedded in dielectric layers. Some patterning schemes require conformal deposition of materials, where the deposited layer should follow the contours of raised and / or recessed features on the substrate surface. Atomic layer deposition (ALD) is generally the preferred method for forming conformal films on substrates because ALD relies on the adsorption of one or more reactants (precursors) to the substrate surface, and the subsequent chemical conversion of the adsorbed layer to the desired material. Because ALD uses sequential reactions that occur on the substrate surface, are separated in time, and are generally limited by the amount of adsorbed reactants, the method can provide thin conformal layers with excellent step coverage.

[0004] Chemical vapor deposition (CVD) is another deposition method widely used in semiconductor processing. In CVD, the reaction occurs within the volume of the processing chamber and is not limited by the amount of reactants adsorbed onto the substrate. Therefore, CVD deposited films are generally less conformal than ALD deposited films. CVD is often used in applications where step coverage is less important.

[0005] ALD and CVD may employ plasma to promote the reaction of the deposition precursors, thereby forming the desired film. Methods utilizing plasma are known as plasma enhanced ALD (PEALD) and plasma enhanced CVD (PECVD). Methods that do not employ plasma are known as thermal ALD and thermal CVD.

[0006] Although ALD and CVD are most commonly used for the deposition of silicon-containing films, such as silicon oxide, silicon nitride, and silicon carbide, these methods are also applicable to the deposition of certain metals, notably tungsten and cobalt.

[0007] The background description provided here is for the purpose of generally presenting the context of the present disclosure. The work of the presently designated inventors is neither explicitly nor implicitly admitted to be prior art against the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed. Summary of the invention

[0008] Methods for depositing molybdenum-containing films, such as metallic molybdenum, molybdenum nitride (MoN x )、Molybdenum carbide (MoC x ), molybdenum boride (MoB x ), Molybdenum silicide (MoSi x ) and combinations thereof, such as molybdenum carbonitride (MoC x N y ), molybdenum boron carbide (MoB x C y ). Precursors for depositing molybdenum-containing films are also provided.

[0009] In one aspect, a precursor for depositing a molybdenum-containing film comprises molybdenum, at least one halogen that forms a bond with the molybdenum, and at least one organic ligand that comprises an element selected from the group consisting of N, O, and S that forms a bond with the molybdenum, provided that the compound is not a molybdenum complex containing both imide and guanidinate organic ligands. In some embodiments, the precursor compound is Mo(X)m(L)n, wherein each X is a halogen that is independently selected from the group consisting of F, Cl, Br, and I; each L is an organic ligand that comprises an element selected from the group consisting of N, O, and S, and wherein m is selected from 1-4, and n is selected from 1-3. In some embodiments, the one or more organic ligands are independently selected from the group consisting of amidinates, amines, amidates, iminopyrrolidinates, diazadienes, beta-iminoamides, alpha-imino alkoxides, beta-aminoalkoxides, beta-diketiminates, beta-ketoiminates, beta-diketonates, thioethers, thiolates, dithiolates, dithiolenes, and pyrazolates, each of which may be substituted or unsubstituted.

[0010] In another aspect, a precursor for depositing a molybdenum-containing film comprises: molybdenum, at least one substituted or unsubstituted 1,4-diazabutadiene-1,3-diene (DAD) ligand bound to the molybdenum, and at least one second ligand. In some embodiments, the DAD ligand is selected from the group consisting of: neutral DAD (neutral DAD) ), monoanion DAD (monoanion (radical anion) ), and dianion DAD (dianion ).

[0011] wherein each R is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents. The second ligand is selected from the group consisting of anionic ligands and neutral ligands, with the proviso that the compound does not include CO as the only second ligand. In some embodiments, the precursor compound is Mo(DAD) m (L) n (X) p , wherein each L is the neutral ligand, each X is the anionic ligand, m is selected from 1-3, n is selected from 0-4, and p is selected from 0-4, wherein n and p are not simultaneously zero. In some embodiments, each neutral ligand L is independently selected from the group consisting of CO, amine, phosphine, nitrile, isonitrile, and thioether, and each anionic ligand X is independently selected from the group consisting of halogen, alkyl, allyl, cyclopentadienyl, alkoxide, amide, and imide.

[0012] In another aspect, a precursor for depositing a molybdenum-containing film is provided, wherein the precursor is Mo2L n , wherein each L is independently an amidinate or guanidinate ligand, n is selected from 2-5, and wherein the precursor comprises a plurality of molybdenum-molybdenum bonds. In some embodiments, the amidinate ligand is: (amidino), wherein each R is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents. In some embodiments, the guanidino ligand is: (guanidinyl), wherein each R is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents.

[0013] On the other hand, the precursor for depositing a molybdenum-containing film is a compound including molybdenum and at least one α-iminothiolene ligand 23 bound to the molybdenum, wherein each R in the α-iminothiolene 23 is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino and alkoxy substituents.

[0014] In some embodiments, the molybdenum-containing precursors provided herein have a vaporization temperature of 200° C. or less.

[0015] In another aspect, a method of forming a molybdenum-containing layer (e.g., molybdenum metal, molybdenum nitride, molybdenum carbide, molybdenum boride, or molybdenum silicide) on a semiconductor substrate is provided, wherein the method comprises: introducing any of the molybdenum-containing precursors disclosed herein into a processing chamber containing the semiconductor substrate; and reacting the molybdenum-containing precursor to form a molybdenum-containing layer on the semiconductor substrate. In some embodiments, the precursor used for deposition is as described above. In one embodiment, the molybdenum-containing precursor is Mo2L n , wherein each L is independently selected from the group consisting of amidate, amidinate and guanidinate ligands, wherein n is selected from 2-5, and wherein the molybdenum-containing precursor includes a plurality of molybdenum-molybdenum bonds.

[0016] In some embodiments, a method for selectively depositing a molybdenum-containing layer on a dielectric layer in the presence of an exposed metal layer on a semiconductor substrate is provided. The method comprises: (a) providing a semiconductor substrate having an exposed metal layer and an exposed dielectric layer, wherein the dielectric layer comprises exposed Si-OH bonds; (b) contacting the semiconductor substrate with a molybdenum-containing precursor, the precursor comprising a ligand having deprotonated nitrogen that forms a bond with molybdenum; and (c) reacting the molybdenum-containing precursor to selectively form the molybdenum-containing layer on the dielectric layer.

[0017] In some embodiments, a method for selectively depositing a molybdenum-containing layer on a metal layer in the presence of an exposed dielectric layer on a semiconductor substrate is provided. The method comprises: (a) providing a semiconductor substrate having an exposed metal layer and an exposed dielectric layer; (b) contacting the semiconductor substrate with a molybdenum-containing precursor, the precursor comprising molybdenum and at least one of a radical anion ligand dithiolene 21 and alpha-iminothiolene 23 bonded to molybdenum, wherein each R is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylamino, alkylsilyl, and alkoxy; and (c) reacting the molybdenum-containing precursor to selectively form a molybdenum-containing layer on the metal layer.

[0018] In some embodiments, a method for forming a platinum metal layer (e.g., a high-purity platinum metal layer) on a semiconductor substrate is provided. In some embodiments, the method includes: (a) introducing a platinum-containing precursor into a processing chamber that accommodates the semiconductor substrate, and (b) reacting the platinum-containing precursor to form platinum metal on the semiconductor substrate. The platinum-containing precursor can be any precursor described herein. On the one hand, the precursor is a compound comprising platinum, at least one halogen that forms a bond with platinum, and at least one organic ligand, the organic ligand comprising an element selected from the group consisting of N, O and S, which forms a bond with platinum. On the other hand, the precursor is a compound comprising platinum and at least one sulfur-containing ligand that forms a platinum-sulfur bond with platinum, wherein the compound does not include a platinum-carbon bond. On the other hand, the platinum precursor is a compound comprising a platinum-molybdenum multiple bond. The precursor may be reacted with at least one reactant selected from the group consisting of hydrogen (H2), ammonia (NH3), hydrazine, amine, diborane (B2H6), silane (SiH4), disilane (Si2H6), water, alcohol, H2S, and thiol, optionally with plasma activation. In some embodiments, the precursor is first reacted with one of the reactants from the group and then with a different reactant from the group. For example, the precursor may be reacted with water, thiol, or H2S and then treated with H2, wherein the H2 treatment may be performed with or without plasma. The reactions in some embodiments occur only on the surface of the substrate. In other embodiments, the reactions may occur within the volume of the processing chamber.

[0019] These methods can be used to deposit molybdenum metal having a low carbon content, such as molybdenum metal having a carbon content less than about 5 atomic percent.

[0020] In another aspect, a system for processing a semiconductor substrate is provided, wherein the system comprises: (a) a processing chamber having a substrate holder and one or more inlets for introducing reactants into the processing chamber; and (b) a system controller comprising program instructions for performing any of the methods provided herein. In some embodiments, the system controller comprises program instructions for: (i) causing any of the molybdenum-containing precursors described herein to be introduced into the processing chamber; and (ii) reacting the molybdenum-containing precursor and forming a molybdenum-containing layer on the semiconductor substrate. In some embodiments, the system controller comprises program instructions for: (i) causing a molybdenum-containing precursor to be introduced into the processing chamber, wherein the molybdenum-containing precursor is Mo2L n, wherein each L is independently selected from the group consisting of amidate, amidinate, and guanidinate ligands, wherein n is 2-5, and wherein the molybdenum-containing precursor comprises a plurality of molybdenum-molybdenum bonds; and (ii) reacting the molybdenum-containing precursor and forming a molybdenum-containing layer on a semiconductor substrate. In some embodiments, the system controller includes program instructions for: (i) causing a molybdenum-containing precursor to be introduced into the processing chamber, wherein the molybdenum-containing precursor comprises molybdenum and at least one organic ligand bonded to molybdenum, wherein the organic ligand comprises at least one of N, O, and S; and (ii) reacting the molybdenum-containing precursor and forming a molybdenum-containing layer on a semiconductor substrate. In some embodiments, the molybdenum-containing precursor comprises molybdenum and at least one sulfur-containing ligand bonded to molybdenum.

[0021] In another aspect, a non-transitory computer machine readable medium comprising program instructions for controlling a deposition tool is provided, wherein the program instructions include code for causing any of the methods described herein.

[0022] The methods and apparatus described herein can be integrated with processes and apparatuses that perform photolithographic patterning. In one aspect, a system is provided, wherein the system includes any apparatus described herein and a stepper.

[0023] The molybdenum-containing precursors described herein can be used in ALD and CVD to deposit molybdenum-containing films in various applications. In some embodiments, the precursors are used to form conformal films. In other embodiments, the precursors are used to fill recessed features with molybdenum-containing materials (e.g., molybdenum metal). For example, the provided precursors and methods can be used to fill contact holes with high-purity molybdenum metal. The provided precursors can be used to deposit high-purity molybdenum with low doping levels of other elements (e.g., O, N, and S).

[0024] These and other aspects of implementations of the subject matter described in this specification are set forth in the drawings and the description that follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1A Examples of ligands that can be used for molybdenum precursors according to embodiments provided herein are provided.

[0026] Figure 1B Examples of sulfur-containing ligands that may be used in molybdenum precursors according to embodiments provided herein are provided.

[0027] Figure 2 Examples of molybdenum precursors according to embodiments provided herein are listed.

[0028] Figure 3 Shown are chemical reaction schemes that can be used to synthesize the molybdenum precursors provided herein.

[0029] Figure 4A is a process flow diagram of a method for forming a molybdenum-containing film according to an embodiment provided herein.

[0030] Figure 4B is a process flow chart of a method for forming a molybdenum metal film according to an embodiment provided herein.

[0031] Figure 5 Illustrative reactions are provided that explain the selective deposition of molybdenum-containing films on dielectrics in the presence of metals.

[0032] Figures 6A-6C A cross-sectional view of a substrate during deposition of a molybdenum-containing film according to embodiments provided herein is shown.

[0033] Figure 7 is a schematic diagram of an apparatus suitable for depositing molybdenum-containing films according to embodiments provided herein.

[0034] Figure 8 A schematic diagram of a multi-station processing system according to embodiments provided herein is shown.

[0035] Fig. 9 A schematic diagram of a multi-station processing system according to embodiments provided herein is shown. DETAILED DESCRIPTION

[0036] Methods and precursors for depositing molybdenum-containing films on semiconductor substrates are provided. These methods and precursors can be used, for example, to deposit a blanket molybdenum-containing layer on a planar substrate, to deposit a conformal molybdenum-containing layer on a substrate having one or more recessed or protruding features, and to fill recessed features with a molybdenum-containing material. In some embodiments, methods and precursors are provided to selectively deposit a molybdenum-containing layer on a dielectric in the presence of exposed metal, or to selectively deposit a molybdenum-containing layer on a metal in the presence of exposed dielectrics.

[0037] These methods can be used to deposit various molybdenum-containing materials, including but not limited to molybdenum metal, molybdenum nitride (MoN x )、Molybdenum carbide (MoC x ), molybdenum boride (MoB x ), Molybdenum silicide (MoSi x ), molybdenum boron carbide (MoB x C y ) and molybdenum carbonitride (MoC x N y ), wherein x and y represent the stoichiometry of these compounds which may vary. The provided precursors are particularly suitable for the deposition of molybdenum metal, for example, the deposition of high purity molybdenum metal with low doping of other elements.

[0038] As used herein, "platinum metal" or "metallic platinum" refers to a material consisting essentially of molybdenum (Mo). Other elements (e.g., C, N, or O) may be present in the platinum metal in small amounts (e.g., a total content of less than about 15 atomic %, or less than about 10%, wherein hydrogen is not included in the calculation). As used herein, "high purity platinum metal" refers to platinum metal containing less than about 5% of other elements (e.g., less than about 1% of other elements), wherein hydrogen is not included in the calculation.

[0039] Molybdenum Nitride (MoN x )、Molybdenum carbide (MoC x ), molybdenum boride (MoB x ), Molybdenum silicide (MoSi x ), molybdenum boron carbide (MoB x C y ) and molybdenum carbonitride (MoC x N y ) refers to a material consisting essentially of molybdenum and nitrogen (MoN x ); Molybdenum and carbon (MoC x ); molybdenum and boron (MoB x ); Molybdenum and Silicon (MoSi x ); molybdenum, boron and carbon (MoB x C y ); and molybdenum, carbon, and nitrogen (MoC x N y ) wherein x and y represent the stoichiometry of these compounds which may vary. Other elements may be present in these compounds in small amounts, such as less than about 10 atomic percent, wherein hydrogen is excluded from the calculations.

[0040] As used herein, the term "semiconductor substrate" refers to a substrate at any stage of semiconductor device manufacturing, which contains semiconductor material anywhere within its structure. It should be understood that the semiconductor material in the semiconductor substrate does not need to be exposed. A semiconductor wafer with multiple layers of other materials (e.g., dielectrics) covering the semiconductor material is an example of a semiconductor substrate. The following detailed description assumes that the disclosed implementation is implemented on a semiconductor wafer (e.g., a 200mm, 300mm, or 450mm semiconductor wafer). However, the disclosed implementation is not limited thereto. The workpiece can have various shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces that can utilize the disclosed implementation include various products, such as printed circuit boards, etc.

[0041] Unless otherwise indicated, the term "about" used in reference to a numerical value includes a range of ±10% of the numerical value being described.

[0042] As used herein, the term "alkyl" refers to a saturated substituent containing exclusively carbon and hydrogen atoms. Alkyl includes straight chain, branched and cyclic groups. Examples of straight chain alkyls include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, etc. Examples of branched chain alkyls include, but are not limited to, isopropyl, isobutyl, sec-butyl and tert-butyl. Examples of cycloalkyls include, but are not limited to, cyclopropyl, cyclopentyl, cyclohexyl, etc.

[0043] As used herein, the term "fluoroalkyl" refers to an alkyl group containing one or more fluorine substituents. In some embodiments, the fluoroalkyl group exclusively contains fluorine substituents, for example in the form of CF3, C2F5, C3F7. The fluoroalkyl group can be linear, branched, and cyclic.

[0044] As used herein, the term "alkylsilyl" refers to a SiR3 group, wherein at least one R is an alkyl group, and each R is independently selected from H and an alkyl group. Alkylsilyl groups include mono-, di-, and tri-alkylsilyl groups. Examples of alkylsilyl groups include trimethylsilyl, dimethylsilyl, methylsilyl, triethylsilyl, diethylsilyl, and ethylsilyl.

[0045] As used herein, the term "alkylamino" refers to a NR2 group wherein at least one R is an alkyl group and each R is independently selected from H and an alkyl group. Examples of alkylamino substituents include dimethylamino and diethylamino substituents.

[0046] The term "alkoxy" refers to an OR group, wherein R is an alkyl group. Examples of alkoxy groups include methoxy, ethoxy, propoxy.

[0047] The term "independently selected" when referring to the selection of R substituents in a molecule containing multiple R groups means that the selection of R substituents on different atoms of the molecule is independent and that the selection of R substituents on an atom with multiple R substituents is also independent.

[0048] Molybdenum metal films have not been widely used in semiconductor processing, at least in part because molybdenum has a high affinity for carbon, nitrogen, and oxygen, making it difficult to obtain molybdenum metal with low doping levels and thus low resistivity. Many common molybdenum deposition precursors exhibit low thermal stability, which results in insufficient step coverage in high aspect ratio features. Existing organometallic molybdenum precursors with molybdenum-carbon bonds can provide high doping levels of carbon into the deposited molybdenum, resulting in high resistivity. For example, the use of molybdenum carbonyl compounds, such as MO(CO)6, can result in a large amount of carbon (e.g., at least 5 atomic %) being incorporated into the growing molybdenum metal film, because molybdenum can act as a catalyst for the dissociation of CO. Although molybdenum halides do not have this problem, existing halide-based molybdenum-containing deposition precursors have many other undesirable characteristics. For example, when molybdenum is deposited on a substrate containing an exposed fluorine-sensitive layer (e.g., a silicon-containing material, such as a silicon oxide-based dielectric), the use of molybdenum hexafluoride (MoF6) requires a fluorine barrier layer and an etch stop layer. Molybdenum pentachloride (MoCl5) is another conventional precursor that has several disadvantages: it has a high melting point and can cause etching of growing molybdenum films. Modification of homoleptic halogenated precursors by exchanging halide ligands for oxo ligands (e.g., in the form of molybdenum oxychlorides MoOCl4 and MoO2Cl2) increases volatility, but these precursors are difficult to reduce to pure molybdenum metal due to the strong molybdenum-oxygen double bond. In addition, MoCl5, MoOCl4, and MoO2Cl2 are all high melting point corrosive solids that are undesirable in high volume manufacturing.

[0049] The molybdenum precursor and deposition method provided herein can overcome one or more of these shortcomings. In some embodiments, a high-purity platinum metal film is deposited by using the provided precursor and method, wherein the deposited high-purity platinum metal film is substantially composed of platinum and has less than about 5% atoms of other elements, such as less than about 3% atoms of other elements, or less than about 1% atoms of other elements (excluding hydrogen from the calculation). In some embodiments, a platinum metal film having a resistivity less than about 50 μΩ·cm is provided, such as a 100A thick film less than about 30 μΩ·cm. In some embodiments, especially when using a fluorine-free precursor, platinum metal can be directly deposited onto a substrate containing exposed fluorine-sensitive materials, and no etching stop layer is required to protect them. For example, platinum metal or other molybdenum-containing films can be deposited onto a substrate containing exposed silicon oxide-based dielectrics, silicon-containing dielectrics (such as silicon nitride and silicon carbide), or amorphous or crystalline silicon or silicon germanium. As used herein, silicon oxide based dielectrics refer to dielectrics containing silicon-oxygen bonds and include thermally grown silicon oxides, silicates, TEOS (tetraethyl orthosilicate)-deposited oxides, and the like.

[0050] The precursors provided herein are selected so that they can be easily reduced to platinum metal and preferably do not contain a platinum-oxygen double bond. In addition, they can be vaporized and are stable at the target temperature and pressure. For example, in some embodiments, the precursor is used for the deposition reaction at a temperature of less than about 450° C. (e.g., less than about 400° C.).

[0051] To maintain appropriate volatility, in many of the embodiments discussed herein, a precursor is selected to have a molecular weight of less than about 450 g / mol (eg, less than about 400 g / mol).

[0052] In general, the molybdenum precursor may include a wide range of molybdenum in oxidation states ranging from 0 to + 6. In some embodiments, molybdenum compounds having molybdenum in the low oxidation states +3, +4, and +5 are preferred.

[0053] Heteroleptic molybdenum compounds containing halides

[0054] In one aspect, a heteroleptic molybdenum compound (i.e., a compound having different types of ligands) containing a halide is used as a precursor for the deposition of a molybdenum-containing film (e.g., for the deposition of molybdenum metal, molybdenum nitride, or molybdenum carbide). In one embodiment, the precursor is a compound comprising molybdenum, at least one halide that forms a bond with the molybdenum, and at least one organic ligand having any of the elements N, O, and S, wherein an atom of any of these elements forms a bond with the molybdenum. Examples of suitable organic ligands that provide nitrogen or oxygen bonding include amidinates, amidates, iminopyrrolidinates, diazadienes, beta-iminoamides, alpha-imino alkoxides, beta-aminoalkoxides, beta-diketiminates, beta-ketoiminates, beta-diketonates, amines, and pyrazolates. Examples of suitable organic ligands that provide sulfur bonding include thioethers, thiolates, dithiolenes, dithiolates, and a-imino thiolenes. These ligands may be substituted or unsubstituted. In some embodiments, the ligands include one or more substituents independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents. The organic ligands can be neutral or anionic (e.g., monoanionic or dianionic), and the platinum can be in various oxidation states, such as +1, +2, +3, +4, +5, and +6.

[0055] The structures of exemplary suitable N and / or O-containing organic ligands 1-17 are shown in FIG1 , while the structures of exemplary suitable S-containing organic ligands 18-25 are shown in Figure 2In some embodiments, each R is independently selected from H, alkyl, fluoroalkyl, alkylsilyl, alkylamino and alkoxy. In some embodiments, each R is independently selected from H, alkyl and fluoroalkyl. In some embodiments, each R is independently selected from H, methyl, ethyl, n-propyl, isopropyl, isobutyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, cyclopropylethyl, cyclopropylpropyl, cyclobutylmethyl and cyclobutylethyl. In some embodiments, each R is an independently selected alkyl. In some embodiments, ligands with branched alkyl substituents (e.g., isopropyl and isobutyl) are preferred because these ligands provide more volatile platinum precursors.

[0056] In some embodiments, at least one organic ligand in the precursor is an amine. Suitable amines include monodentate amines (e.g., monoalkylamines, dialkylamines), bidentate amines (e.g., unsubstituted or N-alkyl-substituted ethylenediamine), and amines of higher denticities (e.g., substituted or unsubstituted diethylenetriamine). An example of a monodentate amine is amine 1 shown in FIG. 1 , wherein at least one R is an alkyl or fluoroalkyl group, and each R is independently selected from the group consisting of H, alkyl, and fluoroalkyl groups. In some embodiments, at least one R is an alkyl group, and each R is independently selected from H and alkyl groups. In some embodiments, at least one organic ligand is an amide group, such as a monoanionic amide group 16, wherein at least one R is an alkyl or fluoroalkyl group, and each R is independently selected from H, alkyl, and fluoroalkyl groups. In some embodiments, at least one organic ligand is an imide group, such as a dianionic imide group 17, wherein R is an alkyl or fluoroalkyl group. Although generally the imido group-containing precursor can be used for the deposition of various molybdenum-containing films (including molybdenum metal), in some embodiments, it is preferably used for the deposition of molybdenum nitride and molybdenum carbonitride (because strong molybdenum-nitrogen bonds are formed), and can be used as a nitrogen source for the resulting film. In some embodiments, at least one organic ligand in the precursor is an amidine group. An example of an amidine group is amidine group 2 shown in Figure 1, wherein each R is independently selected from H, alkyl and fluoroalkyl. Amidine group 2 is a monoanionic ligand that can form two molybdenum-nitrogen bonds, which acts as a bidentate ligand.

[0057] In some embodiments, at least one organic ligand in the precursor is an amide. An example of an amide is amide 3 shown in FIG1 , wherein each R is independently selected from H, alkyl, and fluoroalkyl. Amide 3 is a monoanionic ligand that can form one molybdenum-nitrogen and one molybdenum-oxygen bond, which acts as a bidentate ligand.

[0058] In some embodiments, at least one organic ligand in the precursor is a diazadiene. Examples of diazadienes are 1,4-diazabutadiene-1,3-diene (DAD) 5, 6 and 7, wherein each R is independently selected from H, alkyl and fluoroalkyl. The interesting property of this ligand is that it can exist in a neutral form 5, a monoanionic radical form 6, and a dianionic form 7. Due to the redox activity of the monoanionic (radical) form 6, it can be relatively easily removed during deposition, making the complex of DAD 6 particularly suitable for the deposition of platinum metal and high-purity platinum metal. DAD ligands 5, 6 and 7 can act as bidentate ligands, each of which forms two platinum-nitrogen bonds. In some embodiments, the platinum precursor includes DAD ligands 5, 6 or 7 as organic ligands, wherein each R is independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl.

[0059] In some embodiments, the at least one organic precursor is an iminopyrrolidinyl group (e.g., iminopyrrolidinyl group 4, wherein each R is independently selected from H, alkyl and fluoroalkyl), a β-iminoamide group (e.g., β-iminoamide group 8, wherein each R is independently selected from H, alkyl and fluoroalkyl), an α-iminoalkoxy group (e.g., α-iminoalkoxy group 9, wherein each R is independently selected from H, alkyl and fluoroalkyl), a β-diketoimino group (e.g., β-diketoimino group 10, wherein each R is independently selected from H, alkyl and fluoroalkyl), a β-ketoimino group (e.g., β-ketoimine 11, wherein each R is independently selected from H, alkyl and fluoroalkyl), β-diketone (e.g., β-diketone 12, wherein each R is independently selected from H, alkyl and fluoroalkyl), pyrazol (e.g., pyrazol 13, wherein each R is independently selected from H, alkyl and fluoroalkyl), β-aminoalkoxy (e.g., β-aminoalkoxy 14, wherein each R is independently selected from H, alkyl and fluoroalkyl), or guadinidate 15 (e.g., guadinidate 15, wherein each R is independently selected from H, alkyl and fluoroalkyl). These are monoanionic ligands that can bind to platinum in a bidentate manner.

[0060] In some embodiments, at least one organic precursor is a sulfur-containing ligand capable of forming a molybdenum-sulfur bond. In some embodiments, at least one organic ligand in the precursor is a thioether. The term "thioether" is used broadly herein to include monodentate and polydentate (e.g., bidentate or tridentate) thioethers, as well as ligands containing both thioether and thiol (or other) moieties. An example of a monodentate thioether is a dialkyl sulfide RS, where each R is an alkyl group, such as dimethyl sulfide, diethyl sulfide, diisobutyl sulfide, and the like. An example of a polydentate thioether ligand that also includes a thiol moiety is (SCHCHSCHCHS) 2- Examples of monodentate sulfides are Figure 2The thioether 18 shown in the figure, wherein each R is independently selected from the group consisting of alkyl and fluoroalkyl. In some embodiments, each R is independently selected from the group consisting of methyl, ethyl, n-propyl, isopentyl, n-butyl, isobutyl, sec-butyl and tert-butyl. In some embodiments, the at least one organic ligand is a thiol group, such as a monoanionic thiol group 19, wherein R is an alkyl or fluoroalkyl group. For example, R can be methyl, ethyl, n-propyl, isopentyl, n-butyl, sec-butyl, isobutyl, or tert-butyl. In some embodiments, the thiol group is a dithiol group, such as a dianionic α-dithiol group 24 (wherein each R is independently selected from H, alkyl and fluoroalkyl) or a dianionic β-dithiol group 25 (wherein each R is independently selected from H, alkyl and fluoroalkyl). The dithiol group is capable of forming two platinum-sulfur bonds with platinum.

[0061] In some embodiments, at least one organic ligand in the precursor is a dithiolene. Examples of dithiolene are structures 20, 21 and 22, wherein each R is independently selected from H, alkyl and fluoroalkyl. The ligand (similar to DAD) can exist in a neutral form 20, a monoanionic radical form 21 and a dianionic form 22. Due to the redox activity of the monoanionic radical form 21, it can be relatively easily removed during the deposition and reduction of the platinum precursor, making the complex of dithiolene 21 particularly suitable for the deposition of platinum metal and high-purity platinum metal. Dithiolene ligands 20, 21 and 22 can be used as bidentate ligands, each of which can form two platinum-sulfur bonds. In some embodiments, the platinum precursor includes dithiolene ligands 20, 21 and / or 22 as organic ligands, wherein each R is independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl.

[0062] In some embodiments, the at least one organic ligand in the precursor is an α-iminothiol ene, such as structure 23, wherein each R is independently selected from H, alkyl, and fluoroalkyl. In some embodiments, each R substituent on a carbon atom is independently selected from H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents, and the R substituent on nitrogen is independently selected from alkyl and fluoroalkyl. In some embodiments, the R substituent on nitrogen is independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert-butyl. The ligand (similar to DAD and dithiolene) has a monoanionic radical form as shown in structure 23, which is redox active and easily removed during the reduction process.

[0063] In some embodiments, the molybdenum-containing precursor preferably does not contain a molybdenum-oxygen or molybdenum-nitrogen double bond. In some embodiments, the molybdenum compound does not include both imido and guanidino ligands. In some embodiments, the molybdenum compound does not include imido ligands or guanidino ligands. In some embodiments, the molybdenum compound does not include CO, alkyl, or cyclopentadiene ligands.

[0064] In some embodiments, the precursor is a compound having the formula Mo(X)m(L)n, wherein m is 1-4, n is 1-3, each X is a halide independently selected from F, Cl, Br and I, and each L is an organic ligand as described above, for example, independently selected from amidinates, amidates, iminopyrrolidinates, diazadienes, beta-imino amides, alpha-iminoalkoxides, beta-aminoalkoxys, In some embodiments, in a given ligand, each R is independently selected from the group consisting of H, alkyl and fluoroalkyl.

[0065] In some embodiments, L is a bidentate ligand. Suitable precursors of formula MO(L)C14 utilizing bidentate ligands are exemplified in Figure 3 These are Mo(V) compounds and include amidine-molybdenum complex 27, DAD complex 28, β-diketimine complex 29, pyrazol complex 30, amide complex 31, β-iminoamide complex 32, β-ketoimine complex 33, β-aminoalkoxy complex 34, iminopyrrole complex 35, α-iminoalkoxy complex 36 and β-diketone complex 37.

[0066] Heterolate complexes with halogenated molybdenum bonds and organic ligands described herein can be synthesized by reacting a molybdenum halide starting material with a compound containing an organic ligand in neutral or anionic form. For example, a molybdenum (V) precursor can be prepared using MOCl5 as a starting material. A Mo (III) precursor can be prepared using MOX3(THF)3 as a starting material, wherein X is selected from chlorine, bromine and iodine, and THF is tetrahydrofuran. These starting materials can be treated with ligands in neutral or anionic form (e.g., salts such as lithium or sodium salts) to form heterolate complexes described herein. Examples of reactions that can be used to prepare these complexes are shown in FIG4. Formula 1 shows the use of molybdenum pentachloride to react with lithium amidinate to prepare amidino molybdenum tetrachloride (V). Formula 2 shows the use of molybdenum pentachloride to react with two equivalents of lithium amidinate to prepare bisamidino molybdenum trichloride (V). The stoichiometry of the molybdenum precursor (the number of halides and organic ligands in the resulting precursor) can be controlled by controlling the stoichiometric ratio of the starting materials.

[0067] The reaction can be carried out in various aprotic solvents. For example, the reaction can be carried out in ether solvents (such as tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, methyl tert-butyl ether, 1,2-dimethoxyethane), in hydrocarbon solvents (such as toluene, benzene, heptane, hexane, pentane) or in halogenated hydrocarbon solvents (such as chlorobenzene, dichlorobenzene, fluorobenzene, difluorobenzene, dichloromethane, chloroform, etc.). The reaction can be carried out in a wide temperature range, depending on the boiling point of the solvent and the solubility of the product. In some embodiments, starting material, reaction intermediate and desired product are unstable to moisture and oxygen. Accordingly, the reaction process should utilize protective inert gas (such as nitrogen or argon) to carry out under anhydrous and air-free conditions.

[0068] Heterolate molybdenum compounds containing molybdenum halide bonds and organic ligands described herein can advantageously provide high purity molybdenum metal in CVD and ALD depositions. In addition, the use of these compounds can be associated with reduced etching of substrate materials compared to conventional homoleptic molybdenum halides. These advantages are described for illustrative purposes and are not intended to limit the use of these compounds to only deposition of molybdenum metal or deposition on etch-sensitive substrates.

[0069] In some embodiments, when deposition is performed on fluorine-sensitive materials (e.g., silicon-containing materials), the precursor is selected to be fluorine-free, for example including any of Cl, Br, and I as the halide in the complex. In addition, the use of compounds with fluorinated alkyl substituents can be avoided in these embodiments.

[0070] Sulfur-containing molybdenum compounds

[0071] On the one hand, sulfur-containing molybdenum compounds are used as precursors for depositing molybdenum-containing films, for example, for depositing molybdenum metal, molybdenum sulfide, molybdenum nitride or molybdenum carbide. In some embodiments, the molybdenum compound includes molybdenum and at least one sulfur-containing ligand that provides molybdenum-sulfur bonding. Molybdenum precursors based on sulfur-containing ligands can be used to deposit molybdenum-containing films that are substantially free of impurities, because sulfur impurities are easy to remove compared to oxygen, carbon and nitrogen impurities. In some embodiments, the molybdenum compound does not include a molybdenum-carbon bond and / or does not include a molybdenum-oxygen double bond. In some embodiments, the molybdenum compound does not include a molybdenum-nitrogen double bond. In some embodiments, in the provided molybdenum precursor, molybdenum only forms a bond with a sulfur atom.

[0072] Examples of suitable sulfur-containing ligands that provide sulfur bonding include thioethers, thiols, dithiols, dithiols, thiocarbamates, and α-iminothiolenes. These ligands may include one or more substituents independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylsilyl, alkylamino, and alkoxy substituents. These ligands may be neutral or anionic (e.g., monoanions or dianions), and the platinum may be in various oxidation states, such as 0, +1, +2, +3, +4, +5, and +6.

[0073] In some embodiments, the sulfur-containing ligand is Figure 2 Ligands 18-25 are shown, wherein the R substituents are as described above. Examples of suitable molybdenum precursors include molybdenum thiolates MO(SR)4, wherein R is an alkyl group, such as methyl, ethyl, propyl, butyl. In a specific example, the precursor is tetrakis (tert-butylthiol) molybdenum (IV): MO(SR)4, wherein R is tert-butyl. Another example of a suitable molybdenum precursor is molybdenum thiocarbamate, such as tetrakis (diethyl dithiocarbamate) molybdenum (IV): Each R is independently selected from alkyl (e.g., ethyl, methyl, propyl, butyl) and fluoroalkyl (e.g., CF3). In a specific example, the precursor is tetrakis(diethyldithiocarbamate) molybdenum(IV).

[0074] In some embodiments, dithiol ene complexes of molybdenum are provided, wherein the dithiol ene can be in a neutral form 20, an anionic radical form 21, and a dianionic form 22, wherein each R is independently H, alkyl, or fluoroalkyl.

[0075] The dithiol-ene complex is redox active and can support molybdenum in various oxidation states. The redox reaction of dithiol-ene ligands 20, 21, and 22 is shown in Equation 3:

[0076] In one embodiment, the precursor is MO(21)3, wherein each R in 21 is independently selected from H, alkyl and fluoroalkyl. For example, R can be methyl, ethyl, CF3, etc. This is a homocoordinated Mo(III) compound containing exclusively molybdenum-sulfur bonds.

[0077] In some embodiments, the ligand can provide nitrogen bonding in addition to sulfur bonding. An example of such a ligand is α-iminothiolene 23, which is a redox-active radical anion ligand that can exhibit behavior similar to that of thiols. In some embodiments, the precursor is a Mo(III) compound MO(23)3, wherein each R in compound 23 is independently selected from H, alkyl, and fluoroalkyl.

[0078] In some embodiments, the precursor is MoL n Compounds wherein n is 2 to 6 and L is a sulfur-containing ligand, such as any of the sulfur-containing ligands described herein. In some embodiments, each L is the same sulfur-containing ligand. In other embodiments, the precursor may include different sulfur-containing ligands L. Examples of precursors include Mo(19)2, Mo(19)3, Mo(19)4, Mo(19)5, Mo(19)6, Mo(19)2(18)2, Mo(19)3(18), Mo(19)4(18)2, Mo(21)3, Mo(20)(21)2, Mo(22)3, Mo(21)(22)2, Mo(20)(22)2, Mo(23)3, Mo(24)3, Mo(25)3. The sulfur-containing molybdenum compounds described herein can be synthesized by reacting a molybdenum halide starting material with a compound containing an organic sulfur-containing ligand in neutral or anionic form. For example, a molybdenum (V) precursor can be prepared using MOCl5 as a starting material. Mo(III) or Mo(IV) precursors can be prepared using the corresponding halides or MOX3(L)3 or MOX4(L)2 as starting materials, wherein X is selected from chlorine, bromine and iodine, and L is a neutral Lewis base, such as tetrahydrofuran or diethyl ether. The starting materials can be treated with the desired sulfur-containing ligand in neutral or anionic form (e.g., salts such as lithium or sodium salts) to form the sulfur-containing complexes described herein.

[0079] In one example, the Mo(IV) thiol complex is prepared by reacting molybdenum tetrachloride with lithium thiolate. For example, MOCl4 can react with t-BuSLi in 1,2-dimethoxyethane solvent to form MO(t-BUS)4 compound.

[0080] α-Iminothiolene ligands can be prepared from the corresponding α-iminoketones by thionation using appropriate reagents, such as Lawesson's reagent. The radical anion form of the α-iminothiolene can then be prepared by treatment with an alkali metal such as lithium. The resulting ligands and ligand salts can be reacted with platinum halides to form platinum compounds containing α-iminothiolene.

[0081] Platinum complexes can also be prepared using zero-valent starting materials, such as molybdenum hexacarbonide. The starting material can be treated with a neutral ligand, such as a thioether (dialkyl sulfide), to cause redox neutral ligand exchange. Zero-valent starting materials can also be treated with a ligand precursor, such as bis(diethylthiocarbamoyl) disulfide or bis(trifluoromethyl)-1,2-dithiocyclobutene (bis(triflluoromethyl)-1,2-dithiete), to cause oxidative addition and form the sulfur-containing complexes described herein.

[0082] The reaction can be carried out in various aprotic solvents. For example, the reaction can be carried out in ether solvents, such as tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, methyl tert-butyl ether, 1,2-dimethoxyethane; in hydrocarbon solvents, such as toluene, benzene, heptane, hexane, pentane; or in halogenated hydrocarbon solvents, such as chlorobenzene, dichlorobenzene, fluorobenzene, difluorobenzene, dichloromethane, chloroform, etc. The reaction can be carried out over a wide temperature range, depending on the boiling point of the solvent and the solubility of the product. In some embodiments, the starting material, the reaction intermediate and the desired product are unstable to moisture and oxygen. Therefore, the reaction process should be carried out under anhydrous and air-free conditions using a protective inert gas (such as nitrogen or argon).

[0083] Precursors containing 1,4-diazabutadiene (DAD)

[0084] On the other hand, a platinum precursor containing DAD is provided. DAD can be combined with platinum in its neutral form 5, its free radical-anion form 6 and its dianion form 7. In some embodiments, a homogeneous coordination DAD complex of formula Mo(DAD)m is provided, wherein m is 1 to 3, and each DAD is independently selected from neutral DAD5, free radical-anion DAD6 and dianion DAD7. The oxidation state of platinum in these complexes ranges from 0 to +6. Non-limiting examples of suitable homogeneous coordination DAD complexes include tri-DADMo(III) precursor Mo(6)3, bis-DADMo(IV) precursor Mo(7)2, bis-DADMo(III) precursor Mo(6)(7) and bis-DADMo(II) precursor Mo(6)2.

[0085] In some embodiments, a homocoordinated DAD complex (i.e., a compound having the same ligand) is prepared by reacting a molybdenum halide with a source of a DAD ligand having a desired electronic configuration. For example, the tri-DADMo(III) precursor Mo(6)3 can be synthesized by reacting MoCl3 with three equivalents of a DAD ligand in the form of a radical anion, which can be prepared from a neutral form of the DAD ligand by treating it with an alkali metal (e.g., lithium) in a solvent (e.g., THF), as shown in Formula 4 below:

[0086] In some embodiments, a hetero-coordinated DAD-containing molybdenum compound is provided. In some implementations, the precursor includes molybdenum, at least one DAD ligand bonded to the molybdenum, and at least one second ligand, wherein the DAD may be a neutral DAD6, a radical anion DAD7, or a dianion DAD8, and the second ligand is independently selected from an anionic ligand and a neutral ligand. In some embodiments, the precursor does not contain a CO ligand as the only second ligand. In some embodiments, the precursor is Mo(DAD)m(L)n(X)p, wherein L is a neutral Lewis base ligand, and each L is independently selected from CO, an amine, a phosphine, a thioether, a nitrile and an isonitrile, X is an anionic ligand, and each X is independently selected from a halide, an alkyl, an allyl and a cyclopentadienyl, and m is 1-3, n is 0-4, and p is 0-4. Nitriles are RCN compounds, wherein R is an alkyl. Isonitriles are RNC compounds, wherein R is an alkyl. Other suitable anionic ligands include alkoxy groups, amide groups, imide groups, and any other anionic ligands including donor atoms selected from C, N, O, B, S, Si, Al, and P.

[0087] Examples of heteroleptic DAD-containing precursors include, but are not limited to, Mo(7)2(RCN)Cl, Mo(7)2(RNC)Cl, Mo(8)(CO)3, Mo(6)(13)Cl, Mo(6)(18)Cl2, Mo(6)2Cl, Mo(6)2(14), Mo(6)2(19), and Mo(6)2(24).

[0088] Heterolate DAD-containing precursors can be prepared by a one-pot reaction or by sequential salt metathesis using multiple steps. Molybdenum halide starting materials (e.g., Mo(V), Mo(IV), or Mo(III) halides) can be treated with DAD ligands or other anionic ligands in anionic form. Neutral Lewis base ligands can be displaced using thermal treatment or photoinduced emission.

[0089] Heterolate DAD-containing precursors can also be prepared using zero-valent molybdenum starting materials (eg, molybdenum hexacarbonyl), which can undergo oxidative addition with a redox-active ligand (eg, a DAD ligand).

[0090] In some embodiments, the precursor containing the radical anion DAD ligand 8 is particularly preferred for depositing platinum metal and high purity platinum metal. In the radical anion form 7, the DAD ligand is electronically coupled to the empty platinum d-orbital and is considered to be an electron source for reducing the platinum ion to a zero-valent metal state. After the electron transfer from the ligand to the metal, the volatile neutral DAD ligand 6 can be swept away from the platinum metal growth surface. Since the DAD ligand can be completely removed from the growth surface, the incorporation of impurity elements (such as C and N) is reduced when using the DAD precursor compared to other metal organic precursors. Therefore, the platinum precursor containing the radical anion DAD ligand can be used to deposit high purity platinum metal at low temperatures.

[0091] Molybdenum disulfide precursor

[0092] In another aspect, the precursors used to deposit the molybdenum-containing films are di-molybdenum compounds containing molybdenum-molybdenum bonds (e.g., multiple molybdenum-molybdenum bonds, such as double bonds or any multiple bonds with a bond order of 2 to 5). These precursors are particularly useful for depositing molybdenum metal and high purity molybdenum metal because these compounds are more easily reduced to metallic molybdenum than many mononuclear molybdenum compounds.

[0093] In some embodiments, a precursor for depositing a molybdenum-containing film is provided, wherein the precursor is Mo2L n , wherein each L is independently selected from amido, amidino and guanidino ligands, n is 2-5, and wherein the precursor comprises a plurality of molybdenum-molybdenum bonds. In some embodiments, each L is independently selected from amidino ligand 2, amido ligand 3 and guanidino ligand 15, wherein each R in amidino, amido and guanidino is independently selected from H, alkyl, fluoroalkyl, alkylsilyl, alkylamino and alkoxy substituents. In some embodiments, each R is independently selected from H, alkyl and fluoroalkyl. In some embodiments, each L is amido, and the precursor has the formula Mo2(L)3 or Mo2(L)4. In some embodiments, each L is amido, and the precursor has the formula Mo2(L)3 or Mo2(L)4. In some embodiments, each L is guanidino, and the precursor has the formula Mo2(L)3 or Mo2(L)4. In these complexes, molybdenum has the lower oxidation state 2+ (in Mo2(L)3) as well as 3+ (in Mo2(L)4), making these complexes particularly suitable for easy reduction to molybdenum metal.

[0094] An exemplary structure of an amide paddlewheel dimolybdenum(II) precursor having quadruple molybdenum-molybdenum bonds is shown in Structure 38:

[0095] In some embodiments, each of R and R' is independently selected from alkyl, such as methyl, ethyl, isopropyl, and tert-butyl. In some embodiments, one, two, three, or four amido ligands in 38 may be substituted with amidino or guanidino ligands.

[0096] Diplatinum precursors as described herein can use diplatinum tetraacetate as starting material, by being synthesized with ligand salt (such as lithium amidate) treatment.On the one hand, a container is provided, which holds any precursor as described herein in solid or liquid form.On the other hand, a solution of any one of these precursors is provided, wherein the solvent may include, for example, a high boiling hydrocarbon solvent, such as a higher alkane.In some embodiments, the container holding the platinum precursor (solid or liquid form or solution) is filled with an inert gas, such as nitrogen (N2) or argon (Ar), to prevent the precursor from contacting with air, and the possible decomposition caused by contacting with moisture and / or air.In some embodiments, the container is suitable for vaporizing the precursor in the container.For example, the container may include an inlet and an outlet, wherein the inlet is suitable for being connected with a carrier gas source, and the carrier gas may flow through or pass through the precursor, thereby contributing to the vaporization of the precursor.The outlet is suitable for removing carrier gas and precursor vapor from the container, and is configured to be connected to a conduit, which can be used for transporting the precursor vapor to the treatment chamber. The inlet and outlet each have a closed position and an open position, and for example, a manual valve may be included, which may be used to switch from a closed position to an open position and back. When the container is stored or transported, the inlet and outlet are closed. When the container is assembled to the deposition device used, the inlet and outlet valves may be opened, and the carrier gas may flow into the inlet, and flow out from the outlet and carry the precursor vapor. In some embodiments, the container has an overflow (flow-over) design, wherein the inlet and outlet are located above the surface of the precursor. For example, in a cylindrical container, the inlet and outlet may be located at similar vertical heights (for example, the vertical distance between the inlet and outlet may be less than about 20% of the height of the cylinder). In other embodiments, the container has a bubbler design, wherein the inlet is located below the surface of the precursor, and the outlet is located above the inlet (for example, above the surface of the precursor). For example, in a cylindrical container, the inlet and outlet may be located at a distance from each other in the vertical direction (for example, the vertical distance between the inlet and outlet may be greater than about 30% of the height of the cylinder, for example, greater than about 50%, or greater than about 80%).

[0097] Deposition of Molybdenum-containing Materials

[0098] The molybdenum-containing material can be deposited using the precursors described herein by various deposition methods, such as CVD (including thermal and PECVD) and ALD (including thermal and PEALD). Exemplary methods are deposited by Figure 4AThe process flow chart shown is illustrated. The process starts at 401, which is introduced into a processing chamber that accommodates a semiconductor substrate by introducing a molybdenum precursor described herein. The precursor can be introduced into an inert gas flow in a vaporized form, such as argon, helium or nitrogen (N2). In operation 403 (which can be carried out before, after or during the introduction of the molybdenum-containing precursor 401), the second reactant is introduced into the processing chamber that accommodates the substrate. In some embodiments, the introduction of the molybdenum precursor and the second reactant is in sequence. The chemical properties of the second reactant depend on the chemical properties of the target molybdenum-containing film. For example, in order to deposit platinum metal, the second reactant is generally a reducing reactant (including a reactant that forms a reducing environment after activation in a plasma). Examples of suitable reactants for forming platinum metal include hydrogen (H2), ammonia (NH3), hydrazine (N2H4), amine, diborane (B2H6), silane (SiH4), disilane (Si2H6), alcohol, hydrogen sulfide (H2S) or mercaptan. In some embodiments, H2 is a preferred reducing reactant for depositing platinum metal. In some embodiments, the molybdenum-containing precursor reacts with several reactants in sequence. For example, in some embodiments, the platinum metal is deposited in the following manner: adsorbing a molybdenum-containing precursor layer on a substrate, reacting it with a second reactant, and then reacting it with a third reactant. In one implementation, the molybdenum-containing precursor (first reactant) first reacts with at least one of water, H2S and thiol (second reactant). Then, the substrate containing the reaction precursor is treated with hydrogen (H2) (third reactant). In some embodiments, after introducing each reactant, the treatment chamber is cleaned and / or evacuated. In some embodiments, the first reactant (e.g., water, H2S or thiol) is selected to facilitate the removal of ligands from the molybdenum precursor, and the third reactant (e.g., H2) is selected to remove the residues of the ligands (e.g., containing C, N, S, O impurities) and / or reduce the molybdenum to a zero oxidation state from the surface of the substrate, and form a high-purity platinum metal.

[0099] When depositing a molybdenum-containing film other than platinum metal, a second reactant may be selected so that it is a source of essential elements for the molybdenum-containing film, although in some embodiments these elements may be derived exclusively from ligands. Process conditions (e.g., temperature, pressure, reactant flow rate, and optional plasma power) may be adjusted to favor the chemical properties of a particular film. For example, in some embodiments, borane and silane reactants may be used to deposit materials containing molybdenum boride or molybdenum silicide, and under different conditions, these reactants may produce molybdenum metal alone or in combination with other reactants (e.g., H2). In order to deposit molybdenum nitride, a nitrogen-containing second reactant may be selected in some embodiments, and process conditions may be adjusted so that nitrogen can be included in the film. For example, NH3, N2H4, N2, alkylamines, and alkylhydrazines may be used as second reactants to deposit molybdenum nitride. In order to deposit molybdenum carbide, a carbon-containing second reactant may be used, and process conditions may be adjusted so that carbon can be included in the film. For example, a hydrocarbon may be introduced as a second reactant to form molybdenum carbide. Molybdenum carbonitride films can be formed by introducing nitrogen-containing reactants and / or carbon-containing reactants. In some embodiments, the nitrogen-containing and carbon-containing ligands of the molybdenum precursor can themselves serve as sources of nitrogen and / or carbon. Molybdenum oxide films can be formed by introducing an oxygen-containing second reactant (e.g., O2, O3, N2O, CO2, etc.). The second reactant can be introduced into the processing chamber in the form of a mixture with an inert carrier gas (N2, argon or helium). Molybdenum sulfide films can be deposited using sulfur-containing reactants or by adjusting process conditions so that sulfur from the sulfur-containing molybdenum precursor can be included in the film. Sulfur-containing reactants include H2S, dialkylsulfides, dialkyldisulfides, and mercaptans (e.g., methyl mercaptan, tert-butyl mercaptan).

[0100] In some embodiments, the precursor and the second reactant are allowed to mix in the body of the treatment chamber. In other embodiments, after the molybdenum precursor has been introduced and adsorbed on the surface of the substrate, the treatment chamber is purged with an inert gas and / or evacuated to remove the unadsorbed precursor from the treatment chamber. In some embodiments, the precursor layer on the substrate is adsorption-limited. In other embodiments, before cleaning and / or evacuating the treatment chamber, a thicker molybdenum precursor layer can be formed on the surface of the substrate. Note that when the precursor and the second reactant are introduced in sequence, the order of introduction of the precursor and the second reactant can be reversed. In some embodiments, the second reactant is first introduced and allowed to be adsorbed on the surface of the substrate. Then, clean and / or evacuate the treatment chamber to remove the second reactant from the volume of the treatment chamber, and then introduce the molybdenum precursor.

[0101] Referring to operation 405, the molybdenum precursor reacts with the second reactant to form a layer of molybdenum-containing material on the substrate, wherein the reaction occurs on the surface of the substrate and / or in the body of the processing chamber, and is optionally assisted by plasma. For example, in a CVD process, the precursor may react with the second reactant in the body of the processing chamber. The reaction may be performed thermally or by plasma activation. In an ALD process, the reaction occurs only on the surface and is limited by the amount of adsorbed material on the surface (limited by the amount of molybdenum precursor and / or limited by the amount of adsorbed second reactant). In surface-limited reactions (e.g., in ALD), plasma activation is also possible. For example, an adsorbed layer of a molybdenum precursor may react with a plasma formed in a gas including a hydrogen-containing second reactant (e.g., H2, NH3, CO, alcohol, etc.) to form a molybdenum metal layer. In general, the plasma may be generated directly in the processing chamber housing the substrate (direct plasma), or remotely in a separate compartment, and the generated plasma-activated species is fed into the processing chamber (remote plasma). The temperature during the reaction process may be, for example, between about 20-600°C. In some embodiments, low temperature deposition of about 450° C. or less (e.g., about 400° C. or less, such as between about 100-400° C.) may be performed, which is particularly advantageous for deposition of molybdenum metal. The pressure in the process chamber may be in the range of about 0.1 to 100 Torr, such as between about 0.5-5 Torr in a PEALD process and between 1-60 Torr in a thermal ALD process.

[0102] After the reaction is completed, the formed molybdenum-containing layer can be optionally annealed, as shown in operation 407. Annealing can be performed by increasing the temperature. For example, if the reaction is performed at a relatively low temperature (e.g., a temperature below about 450° C., such as below about 400° C.), the temperature can be increased by, for example, 50-200° C. during annealing. In some embodiments, annealing is performed at a temperature between about 300-500° C.

[0103] An example of a surface-based deposition process for forming a molybdenum metal film on a substrate is provided by Figure 4BThe process flow chart shown is illustrated. In operation 411, a layer of a molybdenum precursor and / or a reduction reactant is formed on the surface of the substrate. In some embodiments, the layer is an adsorption-limited layer. Then, in operation 413, the treatment chamber is cleaned and / or evacuated. This step ensures that the molybdenum precursor and / or the reduction reactant are only present on the surface of the substrate, not in the volume of the treatment chamber. Then, in 415, the molybdenum precursor is optionally activated with plasma to react with the reduction reactant on the surface of the substrate. For example, if only the molybdenum precursor is adsorbed on the surface of the substrate in 411, the reducing agent can be introduced into the treatment chamber and can react with the molybdenum precursor on the surface. If both the molybdenum precursor layer and the reduction reactant layer are formed on the surface of the substrate in 411, the process conditions (for example, using the plasma treatment or temperature increase of the surface) can be adjusted in 413 to activate the reaction. Then, in 417, the treatment chamber is cleaned and / or evacuated, and in 419, operations 411-417 are repeated to form more molybdenum metals. In some embodiments, each cycle of operations 411-417 deposits an average of about In some embodiments, 2-100 cycles are performed. For example, 2-20 cycles may be performed. Between (e.g. ) can be formed with a high degree of control over the layer thickness. This method can be used to form a conformal layer of molybdenum metal with excellent step coverage.

[0104] The molybdenum-containing film can be deposited on a variety of surfaces, including on metals (e.g., copper, nickel, cobalt, tungsten, etc.), dielectrics (e.g., silicon oxide-based dielectrics, silicon nitride, silicon carbide, metal oxides, metal nitrides, etc.), and amorphous silicon and crystalline silicon. In some embodiments, the molybdenum-containing film (e.g., molybdenum metal) is deposited on a substrate including an exposed layer of a dielectric and an exposed layer of a metal.

[0105] In some embodiments, the molybdenum-containing film is selectively deposited on the dielectric in the presence of the exposed metal, and in other embodiments, is deposited on the metal in the presence of the exposed dielectric. As used herein, "selective deposition" refers to a higher rate of deposition on the target surface than on the non-target surface. In some embodiments, the selectivity (the ratio of the deposition rate on the target surface to the deposition rate on the non-target surface) is greater than 2, for example, greater than 5. In some embodiments, the molybdenum-containing film is deposited on the dielectric (e.g., a silicon oxide-based dielectric) and is substantially not deposited on the exposed metal surface.

[0106] Selectivity for deposition on dielectrics in the presence of metals can be achieved by using a molybdenum precursor containing a ligand that is an effective proton acceptor. For example, a ligand containing a basic deprotonated nitrogen atom can be protonated by Si-OH groups on the surface of the substrate, thereby resulting in preferential deposition on silicon oxide-based dielectrics. Examples of these ligands include amidinates, amidates, iminopyrrolidinates, beta-imino amides, alpha-imino alkoxides, beta-amino alkoxides, beta-diketiminates, beta-ketoiminates, beta-diketonates, and pyrazolates. An illustration of the reaction of an amidinated molybdenum precursor with a dielectric surface containing Si-OH groups is shown in Figure 5 middle.

[0107] The selectivity of deposition on metal in the presence of dielectric can be achieved by using self-redox ligands (redox non-innocent ligand) that can serve as electron acceptors. These include radical anion DAD ligand 6, radical anion dithiol ene 21 and α-iminothiol ene 23. In some embodiments, the molybdenum-containing film is selectively deposited on the metal surface in the presence of an exposed dielectric by reacting a molybdenum-containing precursor of a molybdenum-containing compound with dithiol ene 21 radical anion ligand and / or α-iminothiol ene 23 radical anion ligand to form a molybdenum-containing layer. The R groups in 21 and 23 can be any group as described above. In some embodiments, each R is independently selected from H, alkyl and fluoroalkyl. Molybdenum-containing films can be deposited for various applications in semiconductor processing. In some embodiments, a molybdenum-containing film (e.g., platinum metal) is deposited as a conformal layer on a substrate containing one or more recessed or protruding features to a thickness between about 0.1-10nm. In some embodiments, the recessed features are filled with a molybdenum-containing material (e.g., molybdenum metal). A schematic cross-sectional view of an exemplary substrate is shown in Fig. 6A , which shows a substrate 601 having a recessed feature 603. In general, the substrate 601 can include a variety of materials, including dielectrics, metals, metal nitrides, etc. A conformal layer of a molybdenum-containing material 605 is deposited on the substrate 601 using the methods and precursors described herein (e.g., using ALD). The resulting structure is shown in Figure 6B In some applications, the process continues and the recessed feature 603 is filled with a molybdenum-containing material 605 (e.g., a molybdenum-containing metal), such as Figure 6CIn some embodiments, the molybdenum-containing film is deposited using a series of ALD cycles using multiple depositions of conformal films (e.g. Figures 6A-6C In other embodiments, the recessed features can be filled using bottom-up film growth.

[0108] The molybdenum-containing films provided herein, especially high-purity molybdenum metal, can be used in interconnect metallization (e.g., for filling recessed features to form contacts), in logic gate applications in FinFETs, as an adhesion layer or diffusion barrier, and in 3D NAND manufacturing. Application examples include logic and memory contact filling, DRAM buried wordline filling, vertical integrated memory gate and wordline filling, and 3D integration using through-silicon vias (TSVs). Molybdenum has better resistivity adjustment (scale) than tungsten, and in some embodiments, molybdenum is a particularly advantageous metal for filling narrow recessed features (e.g., features with a width of less than about 20nm). In one of the exemplary applications, molybdenum metal is used to make unobstructed contacts. In this application, molybdenum metal is deposited directly into a recessed feature (contact hole) having a width of about 5-100 nm (e.g., about 5-20 nm), wherein the recessed feature is formed in a dielectric layer and includes an exposed dielectric such as silicon oxide, silicon nitride, or a low-k material such as silicon oxycarbide at the sidewalls, exposed silicon or silicon germanium at the bottom. In alternative embodiments, the contact hole prior to deposition may be lined with a barrier layer such as WN, MoN, MoC, or TiN on which the molybdenum metal is deposited. Device

[0109] The deposition methods described herein can be performed in a variety of apparatuses. One suitable apparatus includes: a process chamber having one or more inlets for introducing reactants; a substrate holder in the process chamber configured to hold the substrate in place during deposition; and optionally, a plasma generating mechanism configured to generate a plasma in a process gas. The apparatus may include a controller having program instructions for causing any of the method steps described herein to be performed. The deposition methods described herein may be performed in corresponding ALD and CVD apparatus (available from Lam Research Corp. (Fremont, CA), such as and tool).

[0110] For example, in some embodiments, the apparatus includes a controller having program instructions including instructions for: introducing a molybdenum precursor into a process chamber, wherein the precursor is any of the precursors described herein; and causing a reaction between the molybdenum precursor and a second reactant to form a molybdenum-containing material layer on a substrate. The controller may include program instructions for causing any of the methods described herein.

[0111] Figure 7 An example of a deposition apparatus suitable for depositing molybdenum-containing films using the provided methods is shown. Figure 7 Schematically illustrates an embodiment of a process station 700 that can be used to deposit materials using atomic layer deposition (ALD) and / or chemical vapor deposition (CVD), either of which can be plasma enhanced. For simplicity, the process station 700 is depicted as a stand-alone process station having a process chamber body 702 for maintaining a low pressure environment. However, it should be understood that multiple process stations 700 can be included in a common process tool environment. In addition, it should be understood that in some embodiments, one or more hardware parameters of the process station 700, including those discussed in detail below, can be programmatically adjusted by one or more computer controllers.

[0112] The processing station 700 is in fluid communication with a reactant delivery system 701 to deliver process gases to a distribution showerhead 706. The reactant delivery system 701 includes a mixing vessel 704 for blending and / or conditioning process gases for delivery to the showerhead 706. One or more mixing vessel inlet valves 720 can control the introduction of process gases into the mixing vessel 704. Similarly, a showerhead inlet valve 705 can control the introduction of process gases into the showerhead 706.

[0113] Some molybdenum-containing precursors may be stored in solid or liquid form prior to vaporization at a processing station and subsequently transported to a processing station. Figure 7 Embodiments include a vaporization point 703, which is used to vaporize solid reactants to be supplied to a mixing container 704. In some embodiments, the vaporization point 703 can be a heated evaporator. In some embodiments, an inert gas stream flows through a heated solid molybdenum precursor at less than atmospheric pressure, or bubbles through a heated liquid molybdenum precursor, and transports the precursor vapor to a processing chamber. The precursor vapor produced from such an evaporator will condense in a downstream delivery pipeline. Incompatible gases exposed to condensed reactants can produce small particles. These small particles may block pipelines, hinder valve operation, contaminate substrates, etc. Some methods for dealing with these problems involve cleaning and / or evacuating delivery pipelines to remove residual reactants. However, cleaning delivery pipelines can increase the processing station cycle time and reduce the processing station throughput. Therefore, in some embodiments, the delivery pipeline downstream of the vaporization point 703 can be heat traced. In some examples, the mixing container 704 can also be heat traced. In one non-limiting example, the conduit downstream of vaporization point 703 has an increasing temperature profile from about 100° C. to about 200° C. at mixing vessel 704 .

[0114] The showerhead 706 distributes process gases toward the substrate 712. Figure 7In the illustrated embodiment, substrate 712 is located below showerhead 706 and is shown as being disposed on pedestal 708. It should be understood that showerhead 706 can have any suitable shape and can have any suitable number and arrangement of ports to distribute process gases to substrate 712. Although not explicitly shown, in some embodiments, showerhead 706 is a dual-chamber showerhead comprising at least two types of conduits, wherein the first type of conduit is dedicated to the delivery of molybdenum-containing precursor vapor, and the second type of conduit is dedicated to the delivery of the second (or other) reactant. In these embodiments, the molybdenum-containing precursor is not allowed to mix with the reactant in the conduit before entering the processing chamber, and if continuously delivered to the chamber, the conduit is not shared.

[0115] In some embodiments, microvolume 707 is located below showerhead 706. Performing ALD and / or CVD processes in a microvolume rather than in the entire volume of a processing station can reduce reactant exposure and purge time, can reduce the time to change process conditions (e.g., pressure, temperature, etc.), can limit the exposure of the processing station robot to process gases, etc. Exemplary microvolume sizes include, but are not limited to, volumes between 0.1 liters and 2 liters. This microvolume also affects productivity throughput. When the deposition rate per cycle decreases, the cycle time is also reduced. In some cases, for a given target film thickness, the effect of the cycle time reduction is significant enough to increase the overall yield of the module.

[0116] In some embodiments, the pedestal 708 can be raised or lowered to expose the substrate 712 to the microvolume 707 and / or to change the volume of the microvolume 707. For example, during a substrate transfer phase, the pedestal 708 can be lowered so that the substrate 712 can be loaded on the pedestal 708. During a deposition process phase, the pedestal 708 can be raised to position the substrate 712 within the microvolume 707. In some embodiments, the microvolume 707 can completely surround the substrate 712 and a portion of the pedestal 708 to form an area of ​​high flow impedance during the deposition process.

[0117] Optionally, the pedestal 708 can be lowered and / or raised during portions of the deposition process to adjust process pressure, reactant concentrations, etc. within the microvolume 707. In one case where the process chamber body 702 is maintained at a base pressure during the deposition process, lowering the pedestal 708 can allow the microvolume 707 to be evacuated. Exemplary ratios of microvolume to process chamber volume include, but are not limited to, volume ratios between 1:700 and 1:10. It should be understood that in some embodiments, the pedestal height can be programmatically adjusted by a suitable computer controller.

[0118] Although the exemplary microvolume variations described herein relate to a height-adjustable pedestal, it should be understood that in some embodiments, the position of the showerhead 706 can be adjusted relative to the pedestal 708 to change the volume of the microvolume 707. In addition, it should be understood that the vertical position of the pedestal 708 and / or showerhead 706 can be changed by any suitable mechanism within the scope of the present disclosure. In some embodiments, the pedestal 708 may include a rotation axis for rotating the orientation of the substrate 712. It should be understood that in some embodiments, one or more of these exemplary adjustments can be performed programmatically by one or more appropriate computer controllers.

[0119] Back to Figure 7 In the embodiment shown, the showerhead 706 and the base 708 are in electrical communication with the RF power source 714 and the matching network 716 for powering the plasma. In other embodiments, a device without a plasma generator is used to deposit a molybdenum-containing film using the provided method. In some embodiments, the energy of the plasma can be controlled by controlling one or more of the pressure of the processing station, the concentration of the gas, the radio frequency (RF) source power, the RF source frequency, and the plasma power pulse timing. For example, the RF power source 714 and the matching network 716 can be operated at any suitable power to form a plasma with a component of a desired free radical substance. Similarly, the RF power source 714 can provide RF power of any appropriate frequency. In some embodiments, the RF power source 714 can be configured to control a high-frequency RF power source and a low-frequency RF power source that are independent of each other. Exemplary low-frequency RF frequencies may include, but are not limited to, frequencies between 50kHz and 700kHz. Exemplary high-frequency RF frequencies may include, but are not limited to, frequencies between 1.8MHz and 2.45GHz. It should be understood that any suitable parameter can be adjusted discretely or continuously to provide plasma energy for surface reactions. In one non-limiting example, the plasma power may be intermittently pulsed to reduce ion bombardment of the substrate surface relative to a continuously powered plasma.

[0120] In some embodiments, the plasma can be monitored in situ by one or more plasma monitors. In one case, the plasma power can be monitored by one or more voltage and current sensors (e.g., VI probes). In another case, the plasma density and / or the concentration of the process gas can be measured by one or more optical emission spectrometer sensors (OES). In some embodiments, one or more plasma parameters can be adjusted programmatically based on the measurement results from such an in-situ plasma monitor. For example, an OES sensor can be used in a feedback loop to provide programmatic control of the plasma power. It should be understood that in some embodiments, other monitors can be used to monitor plasma and other process characteristics. Such monitors may include, but are not limited to, infrared (IR) monitors, acoustic monitors, and pressure sensors.

[0121] In some embodiments, plasma can be controlled via input / output control (IOC) sequencing instructions. In one example, instructions for setting plasma conditions for a plasma treatment phase may be included in a corresponding plasma activation recipe phase of a deposition process recipe. In some cases, the process recipe phases may be arranged in sequence so that all instructions for a deposition process phase are executed simultaneously with the process phase. In some embodiments, instructions for setting one or more plasma parameters may be included in a recipe phase before the plasma treatment phase. For example, a first recipe phase may include instructions for setting the flow rate of an inert gas and / or a reactant gas, instructions for setting a plasma generator to a power set point, and time delay instructions for a first recipe phase. A second subsequent recipe phase may include instructions for enabling a plasma generator and time delay instructions for a second recipe phase. A third recipe phase may include instructions for disabling a plasma generator and time delay instructions for a third recipe phase. It should be understood that these recipe phases may be further subdivided and / or iterated in any suitable manner within the scope of the present disclosure.

[0122] In some embodiments, the susceptor 708 can be temperature controlled by a heater 710. Additionally, in some embodiments, pressure control of the deposition processing station 700 can be provided by a butterfly valve 718. Figure 7 In the embodiment shown in FIG. 7 , butterfly valve 718 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some embodiments, the pressure control of the process station 700 can also be adjusted by changing the flow rate of one or more gases introduced into the process station 700.

[0123] Figure 8A schematic diagram of an embodiment of a multi-station processing tool 800 is shown, which has an inbound load lock 802 and an outbound load lock 804, one or both of which may include a remote plasma source. Such a tool can be used to process substrates using the methods provided herein. At atmospheric pressure, a robot 806 is configured to move a wafer from a box loaded by a wafer boat 808 into the inbound load lock 802 via an atmospheric port 810. The wafer is placed on a pedestal 812 in the inbound load lock 802 by the robot 806, the atmospheric port 810 is closed, and the load lock is evacuated. When the inbound load lock 802 includes a remote plasma source, the wafer can be exposed to a remote plasma treatment in the load lock before being introduced into the processing chamber 814. In addition, the wafer can also be heated in the inbound load lock 802, for example to remove moisture and adsorbed gases. Next, a chamber transfer port 816 leading to the processing chamber 814 is opened, and another robot (not shown) places the wafer into the reactor on a pedestal at the first station shown in the reactor for processing. Although Figure 8 The illustrated embodiment includes a load lock, but it will be appreciated that in some embodiments, wafers may be allowed to enter the processing station directly.

[0124] The depicted processing chamber 814 contains four processing stations, Figure 8 In the embodiment shown, the stations are numbered 1 to 4. Each station has a heated susceptor (shown as 818 for station 1) and a gas line inlet. It should be understood that in some embodiments, each processing station can have different or multiple uses. Although the processing chamber 814 depicted includes four stations, it should be understood that the processing chamber according to the present disclosure can have any suitable number of stations. For example, in some embodiments, the processing chamber can have five or more stations, while in other embodiments, the processing chamber can have three or fewer stations.

[0125] Figure 8 Also depicted is an embodiment of a wafer handling system 890 for transferring wafers within the processing chamber 814. In some embodiments, the wafer handling system 890 can transfer wafers between various processing stations and / or between a processing station and a load lock. It should be understood that any suitable wafer handling system can be used. Non-limiting examples include a wafer turntable and a robot for handling wafers. Figure 8 Also depicted is an embodiment of a system controller 850 for controlling process conditions and hardware states of the processing tool 800. The system controller 850 may include one or more memory devices 856, one or more mass storage devices 854, and one or more processors 852. The processor 852 may include a CPU or computer, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0126] In some embodiments, the system controller 850 controls all activities of the processing tool 800. The system controller 850 executes system control software 858 stored in the mass storage device 854, loaded into the memory device 856, and executed on the processor 852. The system control software 858 can include instructions for controlling timing, mixing of gases, chamber and / or station pressures, chamber and / or station temperatures, purge conditions and timing, wafer temperature, RF power level, RF frequency, substrate, pedestal, chuck and / or pedestal position, and other parameters of the specific processing performed by the processing tool 800. The system control software 858 can be configured in any suitable manner. For example, various processing tool component subroutines or control objects can be written to control the operation of the processing tool components necessary to perform various processing tool processes according to the disclosed methods. The system control software 858 can be encoded in any suitable computer-readable programming language.

[0127] In some embodiments, the system control software 858 may include input / output control (IOC) sequencing instructions for controlling the various parameters described above. For example, each stage of the ALD process may include one or more instructions for execution by the system controller 850. Instructions for setting process conditions for the ALD process stage may be included in the corresponding ALD recipe stage. In some embodiments, the ALD recipe stages may be arranged sequentially so that all instructions for the ALD process stage are executed simultaneously with the process stage.

[0128] In some embodiments, other computer software and / or programs stored on the mass storage device 854 and / or the memory device 856 associated with the system controller 850 may be employed. Examples of programs or program segments used for this purpose include substrate positioning programs, process gas control programs, pressure control programs, heater control programs, and plasma control programs.

[0129] The substrate positioning program may contain program code for processing tool components used to load a substrate into the pedestal 818 and control the spacing between the substrate and other parts of the processing tool 800.

[0130] The process gas control program may include code for controlling gas composition and flow rate and optionally for flowing gas into one or more process stations prior to deposition to stabilize the pressure in the process station. The process gas control program may include code for controlling gas composition and flow rate within any disclosed range. The pressure control program may include code for controlling the pressure within the process station by adjusting, for example, a throttle valve in the exhaust system of the process station, gas flow into the process station, etc. The pressure control program may include code for maintaining the pressure in the process station within any disclosed pressure range.

[0131] The heater control program may include code for controlling the flow of current to a heating unit that is used to heat the substrate. Alternatively, the heater control program may control the delivery of a heat transfer gas (e.g., helium) to the substrate. The heater control program may include instructions for maintaining the temperature of the substrate within any disclosed range.

[0132] The plasma control program may include code for setting the RF power level and frequency applied to the processing electrodes in one or more processing stations, for example using any RF power level disclosed herein. The plasma control program may also include code for controlling the duration of each plasma exposure.

[0133] In some embodiments, there may be a user interface associated with the system controller 850. The user interface may include a display screen, a graphical software display of apparatus and / or process conditions, and user input devices such as a pointing device, keyboard, touch screen, microphone, and the like.

[0134] In some embodiments, the parameters adjusted by the system controller 850 may relate to process conditions. Non-limiting examples include process gas composition and flow rate, temperature, pressure, plasma conditions (e.g., RF power level, frequency, and exposure time), etc. These parameters may be provided to the user in the form of a recipe, which may be entered using the user interface.

[0135] Signals for monitoring the process may be provided from various process tool sensors by analog and / or digital input connections of the system controller 850. Signals for controlling the process may be output through analog and / or digital output connections of the process tool 800. Non-limiting examples of process tool sensors that may be monitored include mass flow controllers, pressure sensors (e.g., manometers), thermocouples, etc. Appropriately programmed feedback and control algorithms may be used with the data from these sensors to maintain process conditions.

[0136] Any suitable chamber may be used to implement the disclosed embodiments. Exemplary deposition equipment includes, but is not limited to, Product range of devices, facts The product line is available from Lam Research Corp. (Fremont, California). Two or more stations can perform the same function. Similarly, two or more stations can perform different functions. Each station can be designed / configured as needed to perform a specific function / method.

[0137] Fig. 9900 is a block diagram of a processing system suitable for performing a thin film deposition process according to certain embodiments. System 900 includes a transfer module 903. The transfer module 903 provides a clean, pressurized environment to minimize the risk of contamination when the substrate being processed moves between the various reactor modules. According to certain embodiments, mounted on the transfer module 903 are two multi-station reactors 909 and 910, each reactor capable of performing atomic layer deposition (ALD) and / or chemical vapor deposition (CVD). Reactors 909 and 910 may include multiple stations 911, 913, 915, and 917, which may perform operations sequentially or non-sequentially according to the disclosed embodiments. These stations may include a heated pedestal or substrate support, one or more gas inlets or nozzles, or a dispersion plate.

[0138] Mounted on the transfer module 903 may also be one or more single or multi-station modules 907 that are capable of performing plasma or chemical (non-plasma) pre-cleaning, or any other process associated with the disclosed method. In some cases, the module 907 may be used for various processes, such as preparing a substrate for a deposition process. The module 907 may also be designed / configured to perform various other processes, such as etching or polishing. The system 900 also includes one or more wafer source modules 901, in which wafers are stored before and after processing. An atmospheric manipulator (not shown) in the atmospheric transfer chamber 919 may first move the wafer from the source module 901 to the load lock 921. The wafer transfer device (typically a robot unit) in the transfer module 903 moves the wafer from the load lock 921 to the module mounted on the transfer module 903 and to the module mounted on the transfer module 903.

[0139] In various embodiments, the system controller 929 is used to control process conditions during the deposition process. The controller 929 will typically include one or more memory devices and one or more processors. The processor may include a CPU or calculator, analog and / or digital input / output connections, a stepper motor controller board, and the like.

[0140] The controller 929 can control all of the activities of the deposition apparatus. The system controller 929 executes system control software, which includes a set of instructions for controlling timing, mixtures of gases, chamber pressure, room temperature, wafer temperature, radio frequency (RF) power levels, wafer chuck or pedestal position, and other parameters of a particular process. Other computer programs stored in a memory device associated with the controller 929 may be employed in some embodiments.

[0141] There will typically be a user interface associated with the controller 929. The user interface may include a display screen, a graphical software display of the apparatus and / or process conditions, and user input devices such as a pointing device, keyboard, touch screen, microphone, and the like.

[0142] The system control logic can be configured in any suitable manner. In general, the logic can be designed or configured in hardware and / or software. The instructions for controlling the drive circuit can be hard-coded or provided as software. The instructions can be provided by "programming". Such programming is understood to include any form of logic, including hard-coded logic in digital signal processors, application-specific integrated circuits, and other devices with specific algorithms implemented as hardware. Programming is also understood to include software or firmware instructions that can be executed on a general-purpose processor. The system control software can be encoded in any suitable computer-readable programming language.

[0143] The computer program code for controlling the germanium-containing reducing agent pulses, hydrogen gas flow, and tungsten-containing precursor pulses, as well as other processes in the process sequence, can be written in any commonly used computer-readable programming language: for example, assembly language, C, C++, Pascal, Fortran, or others. The compiled object code or script is executed by a processor to perform the tasks identified in the program. Also as indicated, the program code can be hard-coded.

[0144] Controller parameters are related to process conditions such as, for example, process gas composition and flow rate, temperature, pressure, cooling gas pressure, substrate temperature, and chamber wall temperature. These parameters are provided to the user in the form of recipes and can be input using the user interface. Signals for monitoring the process can be provided through analog and / or digital input connections of the system controller 929. Signals for controlling the process are output through analog and digital output connections of the deposition apparatus 900.

[0145] The system software may be designed or configured in many different ways. For example, various chamber component subroutines or control objects may be written to control the operation of chamber components necessary to perform deposition processes (and in some cases other processes) in accordance with the disclosed embodiments. Examples of programs or program segments for this purpose include substrate positioning code, process gas control code, pressure control code, and heater control code.

[0146] In some implementations, the controller 929 is part of a system that can be part of the above-described embodiments. Such a system can include a semiconductor processing device that includes one or more processing tools, one or more processing chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operations before, during, and after processing semiconductor wafers or substrates. The electronic device can be referred to as a "controller," which can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or the type of system, the controller 929 can be programmed to control any process disclosed herein, including controlling process gas delivery, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings in some systems, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out of tools and other transfer tools and / or load locks connected to or connected to a specific system through an interface.

[0147] In a broad sense, a controller can be defined as an electronic device with various integrated circuits, logic, memory and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. The integrated circuit can include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions transmitted to the controller in the form of various separate settings (or program files), which define operating parameters for performing specific processing on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer for completing one or more processing steps during the preparation of one or more (kinds) of layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0148] In some implementations, the controller may be part of or coupled to a computer that is integrated with, coupled to, or connected to the system or a combination thereof via a network. For example, the controller may be in the "cloud" or all or part of a wafer fab host system, thereby allowing remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of a current process, set processing steps to follow the current process, or start a new process. In some embodiments, a remote computer (e.g., a server) may provide a process recipe to the system via a network, which may include a local network or the Internet. The remote computer may include a user interface that allows input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some embodiments, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be for the type of process to be performed and the type of tool to which the controller is configured to connect or control the tool type. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers that are networked together and work toward a common goal (e.g., the processes and controls described herein). An embodiment of a distributed controller for these purposes may be one or more integrated circuits on the chamber that communicate with one or more remote integrated circuits (e.g., at a platform level or as part of a remote computer) that are combined to control the processes within the chamber.

[0149] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin cleaning chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the preparation and / or manufacture of semiconductor wafers.

[0150] As described above, depending on the process step or steps to be performed by the tool, the controller may communicate with one or more of: other tool circuits or modules, other tool components, combination tools, other tool interfaces, adjacent tools, adjacent tools, tools located throughout the factory, a host computer, another controller, or a material handling tool used in moving containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing facility. Further implementation plans

[0151] The apparatus and processes described herein can be used in conjunction with photolithographic patterning tools or processes, e.g., for preparing or manufacturing semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, though not necessarily, these apparatus and processes will be used or operated together in a common manufacturing facility. Photolithographic patterning of films typically includes some or all of the following steps, each of which enables multiple available tools: (1) applying photoresist to a workpiece, i.e., a substrate, using a spin coating or spray coating tool; (2) curing the photoresist using a hot plate or oven or UV curing tool; (3) exposing the photoresist to visible light or ultraviolet light or x-rays using a tool such as a wafer stepper; (4) developing the resist to selectively remove the resist and thereby pattern it using a tool such as a wet bench; (5) transferring the resist pattern to an underlying film or workpiece by using a dry or plasma assisted etching tool; and (6) removing the resist using a tool such as an RF or microwave plasma resist stripper.

Claims

1. A method for forming a molybdenum metal layer on a semiconductor substrate, the method comprising: (a) introducing a molybdenum-containing precursor into a processing chamber containing the semiconductor substrate, wherein the precursor is a compound comprising: molybdenum; at least one halogen that forms a bond with the molybdenum; and at least one organic ligand comprising an element selected from the group consisting of N, O, and S that forms a bond with molybdenum; and (b) reacting the molybdenum-containing precursor with at least one reactant to form molybdenum metal on the semiconductor substrate.

2. The method according to claim 1, wherein (b) includes reacting the molybdenum-containing precursor with at least one reactant selected from a group consisting of hydrogen (H2), ammonia (NH3), diborane (B2H6), water, H2S, thiols, alcohols, amines, hydrazine, silane (SiH4) and disilane (Si2H6) to form a molybdenum metal layer.

3. The method of claim 2, wherein (b) comprises reacting the molybdenum-containing precursor with hydrogen (H2) with or without plasma. The method according to claim 1 , wherein the reaction in (b) is performed only on the surface of the substrate.

5. The method of claim 1, wherein the reaction in (b) is performed on a surface of the semiconductor substrate, and wherein the method comprises: adsorbing the molybdenum-containing precursor onto the substrate and removing unadsorbed molybdenum-containing precursor from the process chamber prior to the reaction; The adsorbed molybdenum-containing precursor is reacted with a reactant selected from a group consisting of water, alcohol, H2S and thiol, and after the reaction, the surface of the semiconductor substrate is treated with hydrogen (H2) in the presence or absence of plasma to form the molybdenum metal layer.

6. The method according to claim 1, wherein the precursor is Mo(X)m(L)n, wherein Each X is a halogen independently selected from the group consisting of F, Cl, Br and I; and Each L is an organic ligand independently selected from the group consisting of amidine, amine, amide, iminopyrrolidino, diazadiene, β-iminoamido, α-iminoalkoxy, β-aminoalkoxy, β-diketimino, β-ketoimino, β-diketone, thioether, thiol, dithiol, dithiolene and pyrazol, wherein m is 1-4 and n is 1-3.

7. A method for forming a molybdenum metal layer on a semiconductor substrate, the method comprising: (a) introducing a molybdenum-containing precursor into a processing chamber containing the semiconductor substrate, wherein the precursor is a compound comprising: molybdenum; at least one sulfur-containing ligand that forms a molybdenum-sulfur bond with the molybdenum, wherein the compound does not include a molybdenum-carbon bond; and (b) reacting the molybdenum-containing precursor to form molybdenum metal on the semiconductor substrate.

8. The method of claim 7, wherein in the precursor, molybdenum forms only molybdenum-sulfur bonds.

9. The method of claim 7, wherein the at least one sulfur-containing ligand is selected from the group consisting of 18, 19, 20, 21, 22, 23, 24, 25, wherein each R is independently selected from the group consisting of H, alkyl, fluoroalkyl, alkylamino, alkylsilyl, and alkoxy.

10. A method according to claim 7, wherein (b) includes reacting the molybdenum-containing precursor with a reactant selected from a group consisting of hydrogen (H2), ammonia (NH3), diborane (B2H6), water, H2S, thiols, alcohols, amines, silane (SiH4), disilane (Si2H6) and hydrazine to form a molybdenum metal layer.

11. The method of claim 7, wherein the reaction in (b) is performed on a surface of the semiconductor substrate, and wherein the method comprises: adsorbing the molybdenum-containing precursor onto the substrate and removing unadsorbed molybdenum-containing precursor from the process chamber prior to the reaction; The adsorbed molybdenum-containing precursor is reacted with a reactant selected from a group consisting of water, alcohol, H2S and thiol, and after the reaction, the surface of the semiconductor substrate is treated with hydrogen (H2) in the presence or absence of plasma to form the molybdenum metal layer.

12. A precursor for depositing a molybdenum-containing film, wherein the precursor is a compound comprising: molybdenum; at least one halogen which forms a bond with the molybdenum, and At least one organic ligand comprising an element selected from the group consisting of N, O and S, which forms a bond with molybdenum, provided that the compound is not a molybdenum complex containing both imido and guanidino organic ligands.

13. The precursor according to claim 12, wherein the organic ligand is a bidentate ligand.

14. The precursor of claim 12, wherein the precursor does not contain molybdenum-carbon bonds.

15. A system for processing a semiconductor substrate, the system comprising: (a) a process chamber having a substrate holder and one or more inlets for introducing reactants into the process chamber; as well as (b) a system controller including program instructions for: (i) causing a molybdenum-containing precursor to be introduced into the process chamber, the molybdenum-containing precursor being a compound comprising: molybdenum; at least one halogen which forms a bond with the molybdenum, and at least one organic ligand comprising an element selected from the group consisting of N, O, and S that forms a bond with molybdenum; and (ii) reacting the molybdenum-containing precursor and forming a molybdenum-containing layer on the semiconductor substrate.

16. A system for processing a semiconductor substrate, the system comprising: (a) a process chamber having a substrate holder and one or more inlets for introducing reactants into the process chamber; as well as (b) a system controller including program instructions for: (i) causing a molybdenum-containing precursor to be introduced into the process chamber, the molybdenum-containing precursor being a compound comprising: molybdenum; at least one sulfur-containing ligand that forms a molybdenum-sulfur bond with the molybdenum, wherein the compound does not include a molybdenum-carbon bond; and (ii) reacting the molybdenum-containing precursor and forming a molybdenum-containing layer on the semiconductor substrate.

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