Dinuclear molybdenum precursors for deposition of molybdenum-containing films

Abstract

To provide a molybdenum precursor that does not contain oxygen, halogen, or carbonyl groups, and that reacts to form molybdenum metal and molybdenum-based films.SOLUTION: A metal coordination complex is provided which comprises a dinuclear molybdenum and a sterically or electronically compatible phosphine ligand or derivative thereof, and which substantially does not contain oxygen, halogen, or carbonyl groups.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001]

[0001] Embodiments of the present disclosure relate to molybdenum precursors and methods for depositing molybdenum-containing films. More particularly, embodiments of the present disclosure are directed to binuclear molybdenum precursors containing sterically and electronically matched phosphine ligands and methods for using the same. [Background technology]

[0002]

[0002] The semiconductor processing industry continues to strive for higher production yields while increasing the uniformity of layers deposited on substrates with larger surface areas. These same factors, combined with new materials, also increase the density of circuits per unit area of the substrate. As circuit density increases, the need for uniformity and process control over layer thickness increases. As a result, various techniques have been developed for depositing layers on substrates in a cost-effective manner while maintaining control over the layer's properties.

[0003] Chemical vapor deposition (CVD) is one of the most common deposition processes used to deposit layers on substrates. CVD is a flux-dependent deposition technique that requires precise control of the substrate temperature and precursors introduced into the processing chamber to produce a desired layer of uniform thickness. These requirements become more important as substrate size increases, necessitating more complex chamber designs and gas flow techniques to maintain adequate uniformity.

[0004]

[0004] One type of CVD that exhibits excellent process coverage is cyclic deposition, or atomic layer deposition. Cyclic deposition is based on atomic layer epitaxy (ALE), which uses chemisorption techniques to deliver precursor molecules onto a substrate surface in successive cycles. The cycles expose the substrate surface to a first precursor, a purge gas, a second precursor, and a purge gas. The first and second precursors react to form a product compound as a film on the substrate surface. The cycles are repeated to form a layer to a desired thickness.

[0005]

[0005] The increasing complexity of advanced microelectronic devices places stringent demands on currently used deposition techniques. Unfortunately, there are only a limited number of viable chemical precursors available that possess the requisite properties of robust thermal stability, high reactivity, and vapor pressure suitable for film growth to occur. Furthermore, precursors that often meet these requirements still exhibit poor long-term stability and produce thin films that contain high concentrations of contaminants, such as oxygen, nitrogen, and halides, which are often detrimental to the target film application.

[0006] Molybdenum and molybdenum-based films have attractive material and conductive properties. These films have been proposed and tested for applications ranging from front-end to back-end portions of semiconductor and microelectronic devices. However, molybdenum precursors often contain halogens, oxygen, and carbonyl groups. Halogen and oxygen contamination can affect device performance, necessitating additional removal procedures. Carbonyl groups bind strongly to metals, requiring higher thermal budgets or the use of additional reagents for their removal. Furthermore, carbonyl groups can redeposit and contaminate other metal surfaces. The use of high-temperature processes is undesirable for temperature-sensitive substrates (e.g., logic devices). Therefore, there is a need in the art for oxygen-, halogen-, and carbonyl-free molybdenum precursors that react to form molybdenum metal and molybdenum-based films. Summary of the Invention

[0007]

[0007] One or more embodiments of the present disclosure relate to a metal coordination complex. In one or more embodiments, the metal coordination complex comprises a dinuclear molybdenum and a sterically or electronically matched phosphine ligand or derivative thereof, and is substantially free of oxygen, halogen, and carbonyl.

[0008]

[0008] One or more embodiments of the present disclosure relate to a method of depositing a film, in one or more embodiments, the method of depositing a film comprises depositing a compound represented by Formula (I), Formula (II), Formula (III), or Formula (IV): TIFF2025121921000002.tif125170 [wherein Mo-Mo is dinuclear molybdenum, L and TIFF2025121921000003.tif14170 is independently a sterically or electronically matched phosphine ligand or derivative thereof, and one or more of L1 and L2 are independently a sterically or electronically matched phosphine ligand or derivative thereof, or a carbonyl ligand or derivative thereof, and exposing the substrate to a reactant to form a molybdenum-containing film on the substrate.

[0009]

[0009] Further embodiments of the present disclosure relate to methods of depositing films. In one or more embodiments, the method of depositing films includes forming a molybdenum-containing film in a process cycle that includes sequentially exposing a substrate to a dinuclear molybdenum coordination complex precursor, a purge gas, a reactant, and a purge gas.

[0010]

[0010] So that the above-mentioned features of the present disclosure can be understood in detail, a more particular description of the present disclosure briefly summarized above can be made by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only typical embodiments of the present disclosure and therefore should not be considered as limiting its scope. [Brief explanation of the drawings]

[0011] [Figure 1] 1 illustrates a process flow diagram of a method according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] Before describing several exemplary embodiments of the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or carried out in various ways.

[0013]

[0013] Embodiments of the present disclosure provide precursors and processes for depositing molybdenum-containing films. The precursor comprises a dinuclear molybdenum coordination complex. In one or more embodiments, the dinuclear molybdenum coordination complex comprises dinuclear molybdenum and one or more ligands coordinated to the dinuclear molybdenum. In some embodiments, the ligand comprises a phosphine ligand. In some embodiments, the phosphine ligand is sterically and electronically adapted to stabilize and provide highly reactive and thermally sensitive molybdenum(VI) species under ALD and CVD conditions. The processes of various embodiments provide molybdenum-containing films using deposition techniques such as atomic layer deposition (ALD) or chemical vapor deposition (CVD). The dinuclear molybdenum precursor of one or more embodiments is volatile and thermally stable, making it suitable for deposition.

[0014]

[0014] The dinuclear molybdenum coordination complex of one or more embodiments is substantially free of oxygen, halogens, and carbonyl groups. As used herein, the term "substantially free" means that less than about 5% halogen is present in the molybdenum-containing film, on an atomic basis, including less than about 4%, less than about 3%, less than about 2%, less than about 1%, and less than about 0.5%. In some embodiments, the molybdenum-containing film is substantially free of carbonyl groups, and less than about 5% carbonyl groups are present in the molybdenum-containing film, on an atomic basis, including less than about 4%, less than about 3%, less than about 2%, less than about 1%, and less than about 0.5%.

[0015] As used herein, "substrate" refers to any substrate or material surface formed on a substrate upon which a film treatment is performed during a manufacturing process. For example, substrate surfaces upon which treatment can be performed include, depending on the application, materials such as silicon, silicon oxide, strained silicon, silicon-on-insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, but are not limited to, semiconductor wafers. Substrates may be subjected to pretreatment processes to polish, etch, reduce, oxidize, hydroxylate, anneal, and / or bake the substrate surface. In addition to direct film treatment on the surface of the substrate itself, the present invention also allows any of the disclosed film treatment steps to be performed on an underlying layer formed on the substrate, as disclosed in more detail below, and the term "substrate surface" is intended to include such underlying layers as the context indicates. Thus, for example, if a film / layer or partial film / layer is being deposited on a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0016] According to one or more embodiments, the method uses an atomic layer deposition (ALD) process. In such embodiments, the substrate surface is exposed to precursors (or reactive gases) sequentially or substantially sequentially. As used throughout this specification, "substantially sequentially" means that the majority of the precursor exposure period does not overlap with exposure to a co-reagent, although there may be some overlap.

[0017]

[0017] As used in this specification and the appended claims, the terms "precursor," "reactant," "reactive gas," and the like are used interchangeably to refer to any gas species capable of reacting with a film formed on a substrate surface.

[0018] As used herein, "atomic layer deposition" or "cyclic deposition" refers to the sequential exposure of two or more reactive compounds to deposit layers of material on a substrate surface. As used herein and in the appended claims, the terms "reactive compound," "reactive gas," "reactive species," "precursor," "process gas," and the like are used interchangeably to mean a substance having species capable of reacting with a substrate surface or materials on the substrate surface in a surface reaction (e.g., chemisorption, oxidation, reduction). A substrate or a portion of a substrate is sequentially exposed to two or more reactive compounds introduced into a reaction zone of a processing chamber. In a time-domain ALD process, exposure to each reactive compound is separated by a time delay to allow each compound to adhere to and / or react with the substrate surface. In a spatial ALD process, different portions of the substrate surface, or materials on the substrate surface, are exposed to two or more reactive compounds simultaneously, so that no point on the substrate is exposed to multiple reactive compounds at substantially the same time. As used in this specification and the appended claims, the term "substantially" as used in this respect means that a small portion of the substrate may be exposed to multiple reactive gases simultaneously due to diffusion, and simultaneous exposure may not be intended, as will be understood by those skilled in the art.

[0019] In one aspect of a time-domain ALD process, a first reactive gas (i.e., a first precursor or compound A) is pulsed into the reaction zone, followed by a first time delay. Then, a second precursor or compound B is pulsed into the reaction zone, followed by a second delay. During each delay, a purge gas, such as argon, is introduced into the process chamber to purge the reaction zone or remove residual reactive compounds or by-products from the reaction zone. Alternatively, the purge gas may flow continuously throughout the deposition process, with only the purge gas flowing during the time delay between pulses of reactive compounds. The reactive compounds are alternately pulsed until the desired film or film thickness is formed on the substrate surface. In either scenario, the ALD process of pulsing compound A, purge gas, compound B, and purge gas constitutes one cycle. The cycle begins with either compound A or compound B, and continues in each order until the desired film thickness is achieved.

[0020] In one aspect of spatial ALD processing, a first reactive gas and a second reactive gas (e.g., hydrogen radicals) are simultaneously supplied to a reaction zone but separated by an inert gas curtain and / or a vacuum curtain, and the substrate is moved relative to the gas supply system so that any point on the substrate is exposed to both the first reactive gas and the second reactive gas.

[0021] Without intending to be bound by theory, it is believed that the presence of halogens, carbonyl groups, and in some cases, oxygen in the structure of molybdenum (Mo) precursors can present challenges because halogen and oxygen contamination can affect device performance and require additional removal steps. Carbonyls (CO) bind strongly to metals, so their removal requires higher thermal loads or the use of additional reagents. Carbonyls (CO) can redeposit and contaminate other metal surfaces.

[0022] Molybdenum (Mo) can be grown by atomic layer deposition or chemical vapor deposition for many applications. One or more embodiments of the present disclosure advantageously provide an atomic layer deposition or chemical vapor deposition process for forming a molybdenum-containing film. As used in this specification and the appended claims, the term "molybdenum-containing film" refers to a film containing molybdenum atoms, and has about 1 atomic % or more of molybdenum, about 2 atomic % or more of molybdenum, about 3 atomic % or more of molybdenum, about 4 atomic % or more of molybdenum, about 5 atomic % or more of molybdenum, about 10 atomic % or more of molybdenum, about 15 atomic % or more of molybdenum, about 20 atomic % or more of molybdenum, about 25 atomic % or more of molybdenum, about 30 atomic % or more of molybdenum, about 35 atomic % or more of molybdenum, about 40 atomic % or more of molybdenum, about 45 atomic % or more of molybdenum, about 50 atomic % or more of molybdenum, or about 60 atomic % or more of molybdenum. In some embodiments, the molybdenum-containing film comprises one or more of molybdenum metal (elemental molybdenum), molybdenum oxide (MoO, MoO), molybdenum carbide (MoC, MoC), molybdenum silicide (MoSi), or molybdenum nitride (MoN). x It will be appreciated that the use of a molecular formula such as does not imply a particular stoichiometric relationship between the elements, but simply the identity of the major components of the film. For example, MoSi x refers to a film that is primarily composed of molybdenum and silicon atoms. In some embodiments, the primary composition of a particular film (i.e., the sum of the atomic percentages of a particular atom) is greater than or equal to about 95%, 98%, 99%, or 99.5% of the film on an atomic basis.

[0023] 1, one or more embodiments of the present disclosure relate to a method 100 for depositing a film. The method shown in FIG. 1 represents an atomic layer deposition (ALD) process in which a substrate or substrate surface is sequentially exposed to reactive gases in a manner that prevents or minimizes gas-phase reaction of the reactive gases. In some embodiments, the method includes a chemical vapor deposition (CVD) process in which the reactive gases are mixed in a process chamber to enable gas-phase reaction of the reactive gases and deposition of a thin film.

[0024] In some embodiments, method 100 includes a pretreatment operation 105. The pretreatment may be any suitable pretreatment known to those skilled in the art. Suitable pretreatments include, but are not limited to, preheating, cleaning, soaking, removing native oxides, or depositing an adhesion layer (e.g., titanium nitride (TiN)). In one or more embodiments, an adhesion layer such as titanium nitride is deposited in operation 105.

[0025] In deposition 110, a process is performed to deposit a molybdenum-containing film on a substrate (or substrate surface). The deposition process can include one or more operations for forming a molybdenum-containing film on the substrate. In operation 112, the substrate (or substrate surface) is exposed to a molybdenum precursor to deposit a precursor film on the substrate (or substrate surface). The molybdenum precursor can be any suitable molybdenum-containing compound that can react with (i.e., adsorb or chemisorb) the substrate surface to leave a molybdenum-containing species on the substrate surface.

[0026] Current molybdenum precursors for ALD of metal films use halogen- and carbonyl-based ligands to provide sufficient stability at the expense of reduced reactivity and increased processing temperatures. Amide ligands can contribute to nitride impurities. Therefore, one or more embodiments use one or more sterically or electronically matched phosphine ligands or their derivatives to stabilize the resulting complex. This combination provides a molybdenum precursor with improved thermal stability while maintaining high volatility.

[0027]

[0027] In one or more embodiments, the molybdenum precursor comprises a dinuclear molybdenum coordination complex. In one or more embodiments, the dinuclear molybdenum coordination complex comprises one or more of cyclopentadienyl, pentamethylcyclopentadienyl, or derivatives thereof. In one or more embodiments, the dinuclear molybdenum coordination complex has the structure of formula (I), where Mo-Mo is dinuclear molybdenum and L is independently a sterically or electronically matched phosphine ligand or derivative thereof. TIFF2025121921000004.tif65170

[0028] Unless otherwise indicated, the terms "lower alkyl," "alkyl," or "alk," as used herein alone or as part of another group, include both linear and branched hydrocarbon groups, typically containing 1 to 20 carbon atoms in the chain, or 1 to 10 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, isobutyl, pentyl, hexyl, isohexyl, heptyl, 4,4-dimethylpentyl, octyl, 2,2,4-trimethylpentyl, nonyl, decyl, undecyl, dodecyl, and various branched isomers thereof. Such groups may optionally contain from 1 to 4 substituents. Alkyl may be substituted or unsubstituted.

[0029]

[0029] Without intending to be bound by theory, bulky alkyl groups, such as, but not limited to, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, CH2-t-butyl, etc., provide steric protection, prevent "pi-pi stacking" of aromatic rings within ligand L, and increase the volatility of the dinuclear molybdenum precursor.

[0030] In one or more embodiments, phosphine-based ligands, L, are used to prevent ligand dissociation (as a potential decomposition pathway) and increase the thermal stability of the molybdenum precursor.

[0031]

[0031] Thus, in one or more embodiments, L comprises a phosphine ligand or a derivative thereof. In some embodiments, L independently represents TIFF2025121921000005.tif17170, wherein R is independently a substituted or unsubstituted C1 to C 10 In one or more embodiments, R is selected from the group consisting of Me-, Et-, iPr-, tBu-, and TIFF2025121921000006.tif8170 substituents are independently selected from the group consisting of:

[0032] In one or more embodiments, a molybdenum dimer complex having one or more first ligands is exposed to one or more phosphine-based ligands to form a dinuclear molybdenum coordination complex of formula (I). In some embodiments, the first ligand comprises a carbonyl ligand or a derivative thereof. In some embodiments, the molybdenum dimer complex has the structure of formula (III), where Mo-Mo is dinuclear molybdenum, L is independently a sterically or electronically matched phosphine ligand or a derivative thereof, and one or more of L1 and L2 is independently a sterically or electronically matched phosphine ligand or a derivative thereof, or a carbonyl ligand or a derivative thereof. TIFF2025121921000007.tif62170

[0033] In some embodiments, the dinuclear molybdenum precursor has a structure of formula (II), where Mo—Mo is dinuclear molybdenum: TIFF2025121921000008.tif14170 are independently sterically or electronically adapted phosphine ligands or derivatives thereof. TIFF2025121921000009.tif64170

[0034] In some embodiments, TIFF2025121921000010.tif14170 is independent TIFF2025121921000011.tif24170, wherein R is independently substituted or unsubstituted C1 to C 10 In some embodiments, R is Me-, Et-, iPr-, tBu-, and TIFF2025121921000012.tif8170 substituents are independently selected from the group consisting of:

[0035] In one or more embodiments, a molybdenum dimer complex having one or more first ligands is exposed to one or more phosphine-based ligands to form a dinuclear molybdenum coordination complex of formula (II). In some embodiments, the first ligand comprises a carbonyl ligand or a derivative thereof. In some embodiments, the molybdenum dimer complex has the structure of formula (IV), where Mo-Mo is dinuclear molybdenum: TIFF2025121921000013.tif14170 are independently a sterically or electronically matched phosphine ligand or a derivative thereof, and one or more of L1 and L2 are independently a sterically or electronically matched phosphine ligand or a derivative thereof, or a carbonyl ligand or a derivative thereof. TIFF2025121921000014.tif63170

[0036] In one or more embodiments, the dinuclear molybdenum precursor has a structure of Formula (I) or Formula (II), where Mo—Mo is dinuclear molybdenum, L and One or more of TIFF2025121921000015.tif14170 is independently a sterically or electronically adapted phosphine ligand or derivative thereof. TIFF2025121921000016.tif65170

[0037] In some embodiments, L independently represents Represented as TIFF2025121921000017.tif17170, TIFF2025121921000018.tif14170 is independent TIFF2025121921000019.tif23170, wherein R is independently a substituted or unsubstituted C1 to C6 10 In some embodiments, R is Me-, Et-, iPr-, tBu-, and TIFF2025121921000020.tif8170 substituents are independently selected from the group consisting of:

[0038] In one or more embodiments, a molybdenum dimer complex having one or more first ligands is exposed to one or more phosphine-based ligands to form a dinuclear molybdenum precursor of Formula (I) or Formula (II). In some embodiments, the first ligand comprises a carbonyl ligand or a derivative thereof. In some embodiments, the molybdenum dimer complex has the structure of Formula (III) or Formula (IV), where Mo-Mo is dinuclear molybdenum, L and TIFF2025121921000021.tif14170 are independently a sterically or electronically matched phosphine ligand or a derivative thereof, and one or more of L1 and L2 are independently a sterically or electronically matched phosphine ligand or a derivative thereof, or a carbonyl ligand or a derivative thereof. TIFF2025121921000022.tif62170

[0039] As used herein, "substrate surface" refers to any substrate surface upon which a layer may be formed. A substrate surface may have one or more features formed therein, one or more layers formed thereon, and combinations thereof. The substrate (or substrate surface) may be pretreated prior to deposition of a molybdenum-containing layer, for example, by polishing, etching, reducing, oxidizing, halogenating, hydroxylating, annealing, baking, etc.

[0040] The substrate can be any substrate on which a material can be deposited, such as a silicon substrate, a III-V compound substrate, a silicon germanium (SiGe) substrate, an epitaxial substrate, a silicon-on-insulator (SOI) substrate, a display substrate such as a liquid crystal display (LCD), a plasma display, or an electroluminescent (EL) lamp display, a solar array, a solar panel, a light-emitting diode (LED) substrate, a semiconductor wafer, or the like. In some embodiments, one or more additional layers can be disposed on the substrate such that a molybdenum-containing layer is at least partially formed thereon. For example, in some embodiments, a layer including a metal, a nitride, an oxide, or the like, or a combination thereof, can be disposed on the substrate, and a molybdenum-containing layer can be formed on such layer.

[0041] In operation 114, the processing chamber is optionally purged to remove unreacted molybdenum precursor, reaction products, and by-products. When used in this manner, the term "processing chamber" does not encompass the entire interior region of the processing chamber, but also includes the portion of the processing chamber adjacent to the substrate surface. For example, in spatially separated processing chamber sectors, the portion of the processing chamber adjacent to the substrate surface is purged of molybdenum precursor by any suitable technique, including, but not limited to, moving the substrate through a gas curtain to a portion or sector of the processing chamber that is free or substantially free of molybdenum precursor. In one or more embodiments, purging the processing chamber includes applying a reduced pressure. In some embodiments, purging the processing chamber includes flowing a purge gas over the substrate. In some embodiments, the portion of the processing chamber refers to a microvolume or small-volume processing station within the processing chamber. The term "adjacent" in reference to the substrate surface refers to the physical space adjacent to the substrate surface that can provide sufficient space for surface reactions (e.g., precursor adsorption) to occur. In one or more embodiments, the purge gas is selected from one or more of nitrogen (N2), helium (He), and argon (Ar).

[0042] In operation 116, the substrate (or substrate surface) is exposed to a reactant to form one or more molybdenum-containing films on the substrate. The reactant can react with molybdenum-containing species on the substrate surface to form a molybdenum-containing film. In some embodiments, the reactant includes a reducing agent. In one or more embodiments, the reducing agent can include any reducing agent known to those of skill in the art. In other embodiments, the reactant includes an oxidizing agent. In one or more embodiments, the oxidizing agent can include any oxidizing agent known to those of skill in the art. In further embodiments, the reactant includes one or more oxidizing agents and a reducing agent.

[0043] In certain embodiments, the reactant is selected from one or more of 1,1-dimethylhydrazine (DMH), alkylamines, hydrazine, alkylhydrazines, arylhydrazines, hydrogen (H), ammonia (NH), alcohols, water (H0), oxygen (O), ozone (O), nitrous oxide (NO), nitrogen dioxide (NO), peroxides, and plasmas thereof. In some embodiments, the alkylamine is selected from one or more of tert-butylamine (tBuNH), isopropylamine (iPrNH), ethylamine (CHCHNH), diethylamine ((CHCH)NH), or butylamine (BuNH). In some embodiments, the reactants include one or more compounds having the formula R'NH, R'NH, R'N, R'SiNH, (R'Si)NH, (R'Si)N, where each R' is independently H or an alkyl group having 1 to 12 carbon atoms. In some embodiments, the alkylamine consists essentially of one or more of tert-butylamine (tBuNH), isopropylamine (iPrNH), ethylamine (CHCHNH), diethylamine ((CHCH)NH), or butylamine (BuNH).

[0044] In operation 118, the processing chamber is optionally purged after exposure to the reactants. Purging the processing chamber in operation 118 may be the same process as purging in operation 114, or may be a different process. Purging the processing chamber, a portion of the processing chamber, an area adjacent to the substrate surface, etc., removes unreacted reactants, reaction products, and by-products from the area adjacent to the substrate surface.

[0045] In decision 120, the thickness of the deposited film or the number of cycles of the molybdenum precursor and reactant is considered. When the deposited film reaches a predetermined thickness or a predetermined number of processing cycles have been performed, the method 100 moves to an optional post-processing operation 130. In some embodiments, the processing cycle includes sequential exposure of the substrate to a molybdenum precursor, a purge gas, a reactant, and a purge gas. If the deposited film thickness or the number of processing cycles has not reached a predetermined threshold, the method 100 returns to operation 110, where the substrate surface is again exposed to the molybdenum precursor in operation 112, and continues.

[0046] The optional post-treatment operation 130 may be, for example, a process to modify the film properties (e.g., annealing) or a further film deposition process to grow an additional film (e.g., an additional ALD or CVD process). In some embodiments, the optional post-treatment operation 130 may be a process to modify the properties of the deposited film. In some embodiments, the optional post-treatment operation 130 includes annealing the as-deposited film. In some embodiments, the annealing is performed at a temperature in the range of about 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, or 1000°C. The annealing environment in some embodiments includes one or more of an inert gas (e.g., molecular nitrogen (N), argon (Ar)) or a reducing gas (e.g., molecular hydrogen (H) or ammonia (NH)), or an oxidizing agent such as, but not limited to, oxygen (O), ozone (O), or a peroxide. The annealing may be performed for any suitable time. In some embodiments, the film is annealed for a predetermined time ranging from about 15 seconds to about 90 minutes, or from about 1 minute to about 60 minutes. In some embodiments, annealing the as-deposited film increases the film's density, decreases its resistivity, and / or increases the film's purity.

[0047] Method 100 can be performed at any suitable temperature, depending, for example, on the molybdenum precursor, the reactants, or the thermal budget of the apparatus. In one or more embodiments, the use of high temperature processes may be undesirable for temperature-sensitive substrates, such as logic devices. In some embodiments, exposure to the molybdenum precursor (operation 112) and exposure to the reactants (operation 116) occurs at the same temperature. In some embodiments, the substrate is maintained at a temperature between 20°C and 650°C, between 20°C and 500°C, between 20°C and 400°C, between 20°C and 300°C, between 50°C and 650°C, between 50°C and 500°C, between 50°C and 400°C, between 50°C and 300°C, between 100°C and 650°C, between 100°C and 500°C, between 100°C and 400°C, or between 100°C and 300°C. In some embodiments, the substrate is maintained at a temperature of 20°C to <650°C, 20°C to <500°C, 20°C to <400°C, 20°C to <300°C, 50°C to <650°C, 50°C to <500°C, 50°C to <400°C, 50°C to <300°C, 100°C to <650°C, 100°C to <500°C, 100°C to <400°C, or 100°C to <300°C.

[0048] In some embodiments, the exposure to the molybdenum precursor (operation 112) is performed at a different temperature than the exposure to the reactant (operation 116). In some embodiments, the substrate is exposed to the molybdenum precursor (operation 112) at a first temperature in the range of 20°C to 650°C, 20°C to 500°C, 20°C to 400°C, 20°C to 300°C, 50°C to 650°C, 50°C to 500°C, 50°C to 400°C, 50°C to 300°C, 100°C to 650°C, 100°C to 500°C, 100°C to 400°C, or 100°C to 300°C. In some embodiments, the substrate is exposed to the molybdenum precursor at a first temperature in the range of 20°C to <650°C, 20°C to <500°C, 20°C to <400°C, 20°C to <300°C, 50°C to <650°C, 50°C to <500°C, 50°C to <400°C, 50°C to <300°C, 100°C to <650°C, 100°C to <500°C, 100°C to <400°C, or 100°C to <300°C (operation 112). In some embodiments, the reactants react with the precursor film at a temperature ranging from 20°C to 650°C, 20°C to 500°C, 20°C to 400°C, 20°C to 300°C, 50°C to 650°C, 50°C to 500°C, 50°C to 400°C, 50°C to 300°C, 100°C to 650°C, 100°C to 500°C, 100°C to 400°C, or 100°C to 300°C (operation 116). In some embodiments, the reactants react with the precursor film at a temperature in the range of 20°C to <650°C, 20°C to <500°C, 20°C to <400°C, 20°C to <300°C, 50°C to <650°C, 50°C to <500°C, 50°C to <400°C, 50°C to <300°C, 100°C to <650°C, 100°C to <500°C, 100°C to <400°C, or 100°C to <300°C (operation 116).

[0049] In the embodiment shown in Figure 1, the substrate (or substrate surface) is sequentially exposed to the molybdenum precursor and reactant in the deposition operation 110. In another embodiment, not shown, the substrate (or substrate surface) is simultaneously exposed to the molybdenum precursor and reactant in a CVD reaction. In a CVD reaction, the substrate (or substrate surface) can be exposed to a gaseous mixture of the molybdenum precursor and reactant to deposit a molybdenum-containing film having a predetermined thickness. In a CVD reaction, the molybdenum-containing film can be deposited in a single exposure to the reactive gas mixture, or multiple exposures to the reactive gas mixture with intervening purges can be used.

[0050] In some embodiments, the formed molybdenum-containing film comprises elemental molybdenum. In other words, in some embodiments, the molybdenum-containing film comprises a metal film containing molybdenum. In some embodiments, the metal film consists essentially of molybdenum. As used in this manner, the term "consisting essentially of molybdenum" means that the molybdenum-containing film is greater than or equal to about 80%, 85%, 90%, 95%, 98%, 99%, or 99.5% molybdenum on an atomic basis. Measurements of the composition of molybdenum-containing films refer to the bulk of the film, excluding interfacial regions where diffusion of elements from adjacent films may occur.

[0051] In other embodiments, the molybdenum-containing film is a molybdenum oxide (MoO) film having an oxygen content of about 5%, 7.5%, 10%, 12.5, or 15% or more on an atomic basis. x In some embodiments, the molybdenum-containing film comprises an oxygen content in the range of about 2% to about 30%, or in the range of about 3% to about 25%, or in the range of about 4% to about 20%, on an atomic basis.

[0052] In other embodiments, the molybdenum-containing film is molybdenum carbide (MoC) having a carbon content of about 5%, 7.5%, 10%, 12.5, or 15% or more on an atomic basis. xIn some embodiments, the molybdenum-containing film comprises a carbon content in the range of about 2% to about 30%, or in the range of about 3% to about 25%, or in the range of about 4% to about 20%, on an atomic basis.

[0053]

[0053] Deposition operation 110 can be repeated to form one or more of a molybdenum oxide, molybdenum carbide, molybdenum silicide, or molybdenum nitride film having a predetermined thickness. In some embodiments, deposition operation 110 is repeated to form one or more of a molybdenum oxide, molybdenum carbide, molybdenum silicide, or molybdenum nitride film having a thickness in the range of about 0.3 nm to about 100 nm, or in the range of about 30 Å to about 3000 Å.

[0054] One or more embodiments of the present disclosure relate to methods for depositing molybdenum-containing films in high aspect ratio features. High aspect ratio features are trenches, vias, or pillars having height:width ratios of about 10, 20, or 50 or more. In some embodiments, the molybdenum-containing film is conformally deposited on the high aspect ratio feature. When used in this manner, the conformal film has a thickness near the top of the feature that is in the range of about 80-120% of the thickness at the bottom of the feature.

[0055] Some embodiments of the present disclosure relate to methods for bottom-up gap filling of features. A bottom-up gap filling process fills a feature from the bottom, whereas a conformal process fills the feature from the bottom and the sides. In some embodiments, the feature has a first material (e.g., nitride) on the bottom and a second material (e.g., oxide) on the sidewalls. A molybdenum-containing film is deposited selectively on the first material relative to the second material such that the molybdenum-containing film fills the feature in a bottom-up manner.

[0056] According to one or more embodiments, the substrate is subjected to processing before and / or after the formation of the layer. This processing can be performed in the same chamber or in one or more separate processing chambers. In some embodiments, the substrate is moved from the first chamber to a separate, second chamber for further processing. The substrate can be moved directly from the first chamber to another processing chamber, or it can be moved from the first chamber to one or more transfer chambers and then to another processing chamber. Thus, the processing equipment can include multiple chambers in communication with a transfer station. This type of equipment is sometimes referred to as a "cluster tool" or a "cluster system," among other terms.

[0057] Generally, a cluster tool is a modular system containing multiple chambers that perform various functions, including substrate center detection and orientation, degassing, annealing, deposition, and / or etching. According to one or more embodiments, the cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber can house a robot capable of shuttled substrates between processing chambers and load lock chambers. The transfer chamber is typically maintained at reduced pressure and provides an intermediate stage for shuttled substrates from one chamber to another and / or to a load lock chamber located at the front end of the cluster tool. Two well-known cluster tools that can be adapted for the present disclosure are the Centura® and Endura®, both available from Applied Materials, Inc. of Santa Clara, California. However, the exact arrangement and combination of chambers can be varied to perform specific steps of the processes described herein. Other processing chambers that may be used include, but are not limited to, cyclic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, pre-cleaning, chemical cleaning, thermal treatments such as RTP, plasma nitridation, degassing, alignment, hydroxylation, and other substrate processing. Performing processing in a cluster tool chamber avoids surface contamination of the substrate from atmospheric impurities without oxidation before depositing the next film.

[0058] According to one or more embodiments, the substrate is continuously under reduced pressure or "load-lock" conditions and is not exposed to ambient air as it moves from one chamber to the next. The transfer chamber is therefore under reduced pressure and is "pumped down" under reduced pressure. An inert gas may be present in the processing chamber or transfer chamber. In some embodiments, an inert gas is used as a purge gas to remove some or all of the reactants (e.g., reactants). According to one or more embodiments, a purge gas is injected into the outlet of the deposition chamber to prevent the reactants (e.g., reactants) from moving from the deposition chamber to the transfer chamber and / or additional processing chambers. Thus, the flow of inert gas forms a curtain at the outlet of the chamber.

[0059] Substrates can be processed in a single-substrate deposition chamber, where a single substrate is loaded, processed, and unloaded before another substrate is processed. Substrates can also be processed continuously, similar to a conveyor system, where multiple substrates are individually loaded into a first portion of the chamber, moved through the chamber, and unloaded from a second portion of the chamber. The geometry of the chamber and associated conveyor system can form a linear or curved path. Additionally, the processing chamber can be a carousel, where multiple substrates move about a central axis and are exposed to processes such as deposition, etching, annealing, cleaning, etc., throughout the carousel path.

[0060] During processing, the substrate may be heated or cooled. Such heating or cooling can be achieved by any suitable means, including, but not limited to, altering the temperature of the substrate support and flowing heated or cooled gases over the substrate surface. In some embodiments, the substrate support includes a heater / cooler that can be controlled to conductively change the substrate temperature. In one or more embodiments, the gas used (either a reactive gas or an inert gas) is heated or cooled to locally change the substrate temperature. In some embodiments, a heater / cooler is positioned within the chamber adjacent to the substrate surface to convectively change the substrate temperature.

[0061] The substrate can be stationary or rotated during processing. A rotating substrate can be rotated (about the substrate axis) continuously or in discrete steps. For example, the substrate can be rotated throughout the entire process, or the substrate can be rotated only a small amount between exposures to different reactive or purge gases. Rotating the substrate (continuously or in steps) during processing can help minimize the effects of local variations in gas flow profiles, for example, and produce a more uniform deposition or etching.

[0062] The present disclosure will now be described with reference to the following examples. Before describing certain exemplary embodiments of the present disclosure, it is to be understood that the present disclosure is not limited to the details of construction or process steps set forth in the following description. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways.

[0063] Example

[0064] Example 1: Preparation of phosphine-substituted dinuclear molybdenum complexes

[0065] The target compounds bearing monodentate or bidentate phosphine ligands were prepared by dissolving the starting Cp-based Mo precursor in acetonitrile followed by the addition of the corresponding alkylphosphine. The resulting mixture was heated under reflux to monitor the reaction progress. 31 The reaction was monitored by P NMR spectroscopy. Upon completion, all volatiles were removed under vacuum to afford the molybdenum dinuclear system in good to moderate yield.

[0064]

[0066] Example 2: Atomic layer deposition of molybdenum-containing films

[0067] General Procedure: A silicon substrate is positioned in a processing chamber. A molybdenum precursor is flowed into the processing chamber in a nitrogen (N2) gas atmosphere over the silicon substrate, leaving the surface terminated with the molybdenum precursor. Unreacted precursor and by-products are purged from the chamber. A co-reactant is then introduced into the chamber and reacts with the surface-bound molybdenum species. Again, excess co-reactant and by-products are removed from the chamber. The resulting material on the substrate is a molybdenum-containing film.

[0065]

[0068] Spatially relative terms such as "beneath," "below," "lower," "above," "upper," and the like may be used herein to describe the relationship of one element or feature to another element or feature shown in the figures for ease of description. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, an element described as "below" or "beneath" another element or feature would therefore be oriented "above" the other element or feature. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatially relative descriptors used herein interpreted accordingly.

[0066]

[0069] The use of the terms "a," "an," and "the" and similar referents in the context of describing the materials and methods discussed herein (particularly in the context of the claims below) should be construed to cover both the singular and the plural unless otherwise stated herein or clearly contradicted by context. The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each individual value falling within the range, unless otherwise stated herein, and each individual value is incorporated into the specification as if set forth individually herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "etc."), provided herein is intended merely to better clarify the materials and methods and does not impose a limitation on scope unless otherwise specified in the claims. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosed materials and methods.

[0067]

[0070] References throughout this specification to "one embodiment," "a particular embodiment," "one or more embodiments," or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of phrases such as "in one or more embodiments," "a particular embodiment," "in an embodiment," or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment of the present disclosure. In one or more embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner.

[0068]

[0071] Although the disclosure herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed method and apparatus without departing from the spirit and scope of the present disclosure. Therefore, it is intended that the present disclosure cover modifications and variations that come within the scope of the appended claims and their equivalents.

Claims

1. A metal coordination complex comprising a dinuclear molybdenum and a sterically or electronically matched phosphine ligand or derivative thereof, which is substantially free of oxygen, halogen, and carbonyl.

2. Formula (I), Formula (II), Formula (III), or Formula (IV), [wherein Mo—Mo is dinuclear molybdenum; L and are independently a sterically or electronically adapted phosphine ligand or derivative thereof; L １ and L ２ one or more of which are independently a sterically or electronically matched phosphine ligand or derivative thereof, or a carbonyl ligand or derivative thereof.

2. The metal coordination complex of claim 1 having the structure:

3. L becomes independent or became independent and R is independently substituted or unsubstituted C １ ~C １０ 3. The metal coordination complex of claim 2, wherein the alkyl group is an alkyl group.

4. R is Me-, Et-, iPr-, tBu-, and 4. The metal coordination complex of claim 3, wherein the substituents are independently selected from:

5. Formula (I), Formula (II), Formula (III), or Formula (IV), [wherein Mo—Mo is dinuclear molybdenum; L and are independently a sterically or electronically adapted phosphine ligand or derivative thereof; L １ and L ２ one or more of which are independently a sterically or electronically matched phosphine ligand or derivative thereof, or a carbonyl ligand or derivative thereof. exposing the substrate to a dinuclear molybdenum coordination complex having the structure: exposing the substrate to a reactant to form a molybdenum-containing film on the substrate; A method of depositing a film comprising:

6. L becomes independent and became independent and R is independently substituted or unsubstituted C １ ~C １０ The method of claim 5, wherein the group is an alkyl group.

7. R is Me-, Et-, iPr-, tBu-, and 7. The method of claim 6, wherein the aryl group is independently selected from:

8. The method of claim 5 , wherein the method is one or more of chemical vapor deposition or atomic layer deposition.

9. The method of claim 5, wherein the reactant reacts with the film at a temperature ranging from 100°C to <400°C.

10. The method of claim 5 , wherein the reactants include one or more of an oxidizing agent and a reducing agent.

11. 6. The method of claim 5, wherein the molybdenum-containing film comprises one or more of a molybdenum metal (elemental Mo) film, a molybdenum oxide film, a molybdenum carbide film, a molybdenum silicide film, and a molybdenum nitride film.

12. The method of claim 5 , wherein the substrate is exposed to the dinuclear molybdenum coordination complex and the reactant sequentially.

13. The method of claim 5 , wherein the substrate is exposed to the dinuclear molybdenum coordination complex and the reactant simultaneously.

14. 6. The method of claim 5, further comprising purging the dinuclear molybdenum coordination complex from the substrate prior to exposing the substrate to the reactant.

15. The method of claim 14 , wherein the purging comprises one or more of applying a vacuum or flowing a purge gas over the substrate.

16. 6. The method of claim 5, further comprising repeating the method to provide a molybdenum-containing film having a thickness of about 0.3 to about 100 nm.

17. The purge gas is nitrogen (N ２ 20. The method of claim 15, wherein the gas comprises one or more of: helium (He), and argon (Ar).

18. A method of depositing a film comprising forming a molybdenum-containing film in a process cycle comprising sequentially exposing a substrate to a dinuclear molybdenum coordination complex precursor, a purge gas, a reactant, and a purge gas.

19. The dinuclear molybdenum coordination complex is represented by formula (I), formula (II), formula (III), or formula (IV): [wherein Mo—Mo is dinuclear molybdenum; L and are independently a sterically or electronically adapted phosphine ligand or derivative thereof; L １ and L ２ one or more of which are independently a sterically or electronically matched phosphine ligand or derivative thereof, or a carbonyl ligand or derivative thereof.

20. The method of claim 18 having the structure:

20. L becomes independent and became independent and R is independently substituted or unsubstituted C １ ~C １０ 20. The method of claim 19, wherein the group is an alkyl group.

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