Method for forming transition metal-containing film on substrate by periodic deposition process

Abstract

To provide a method for forming a transition metal-containing film on a substrate by a periodic deposition process, especially a method for forming a cobalt- or nickel-containing film.SOLUTION: A method for forming a transition metal-containing film having a film thickness below 50 nanometers and an electric resistivity below 50 μΩ-cm includes steps of: bringing a substrate into contact with a first vapor-phase reaction substance containing a transition metal halide compound containing a bidentate nitrogen-containing additional ligand; and bringing the substrate into contact with a second vapor-phase reaction substance containing a reducing agent precursor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] Parties to the Joint Research Agreement The invention claimed in this application was made by, for, and / or in connection with a Joint Research Agreement between the University of Helsinki and ASM Microchemistry Oy, which was in effect on or before the date the claimed invention was made, and which was made as a result of activities undertaken within the scope of the Agreement.

[0002] The present disclosure relates generally to methods for forming transition metal-containing films, particularly cobalt or nickel-containing films, on a substrate by a cyclic deposition process. [Background technology]

[0003] Semiconductor device manufacturing processes at advanced technology nodes generally require state-of-the-art deposition techniques to form transition metal-containing films, such as, for example, one or more elemental transition metals or transition metal nitrides.

[0004] A common requirement for the deposition of transition metal-containing films is that the deposition process is highly conformal. For example, conformal deposition is often required to uniformly deposit transition metal-containing films on three-dimensional structures including high aspect ratio features. Another common requirement for the deposition of transition metal-containing films is that the deposition process is capable of depositing continuous ultra-thin films over large substrate areas. In the specific case where the transition metal-containing film is conductive, the deposition process may need to be optimized to produce a film with low electrical resistivity.

[0005] Cyclic deposition processes, such as atomic layer deposition (ALD) and cyclic chemical vapor deposition (CCVD), sequentially introduce one or more precursors (reactants) into a reaction chamber where the precursors react with the surface of a substrate, one at a time, in a sequential, self-limiting manner. Cyclic deposition processes have been demonstrated to produce metal-containing films with excellent conformality and atomic-level thickness control.

[0006] Cyclic deposition processes may be used to deposit transition metal-containing films. However, suitable chemical precursors for cyclic deposition of transition metal-containing films, and in particular films containing cobalt or nickel, are uncommon and cost prohibitive. Furthermore, transition metal-containing films may benefit from having low electrical resistivity, especially when the transition metal-containing films may be used as electrode components in semiconductor device structures.

[0007] Thus, cyclic deposition techniques are desirable for forming transition metal-containing films, particularly cobalt or nickel-containing films having low electrical resistivity. Summary of the Invention [Means for solving the problem]

[0008] This Summary is provided to introduce a selection of concepts in a simplified form that are described in further detail below in the Detailed Description of Exemplary Embodiments of this Disclosure. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0009] In some embodiments of the present disclosure, a method is provided for forming a transition metal-containing film on a substrate by a cyclic deposition process. The method may include contacting the substrate with a first gas phase reactant comprising a transition metal halide compound comprising a bidentate nitrogen-containing additional ligand and contacting the substrate with a second gas phase reactant comprising a reducing agent precursor, wherein the transition metal-containing film has an electrical resistivity of less than 50 μΩ-cm at a film thickness of less than 50 nanometers.

[0010] For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention are described herein above. Of course, it should be understood that not necessarily all such objects or advantages may be achieved by any particular embodiment of the invention. Thus, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages, for example, as taught or suggested herein, without necessarily achieving other objects or advantages as may be taught or suggested herein.

[0011] All of these embodiments are intended to be within the scope of the invention disclosed herein. These and other embodiments will be readily apparent to those skilled in the art from the following detailed description of several embodiments, taken in conjunction with the accompanying drawings, and the invention is not limited to any particular embodiment disclosed. [Brief description of the drawings]

[0012] While the specification concludes with claims particularly pointing out and distinctly claiming what are regarded as embodiments of the present disclosure, the advantages of the presently disclosed embodiments may be more readily ascertained from the following description of certain specific examples of the presently disclosed embodiments when read in conjunction with the accompanying drawings.

[0013] [Figure 1] FIG. 1 illustrates an exemplary cyclic deposition process flow according to an embodiment of the present disclosure.

[0014] [Diagram 2] FIG. 2 shows X-ray photoelectron spectroscopy data obtained from an exemplary transition metal-containing film deposited according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Although several embodiments and examples are disclosed below, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments and / or applications of the present invention, as well as obvious modifications and equivalents thereof, and therefore it is not intended that the scope of the disclosed invention should be limited by the specific disclosed embodiments described below.

[0016] The figures shown herein are not meant to be actual illustrations of any particular materials, structures or devices, but merely idealized representations used to explain embodiments of the present disclosure.

[0017] As used herein, the term "cyclic deposition" refers to the sequential introduction of precursors (reactants) into a reaction chamber to deposit a film on a substrate, and includes atomic layer deposition and cyclic deposition. These include deposition techniques such as chemical vapor deposition.

[0018] As used herein, the term "cyclic chemical vapor deposition" can refer to any process in which a substrate is sequentially exposed to two or more volatile precursors that react and / or decompose on the substrate to produce a desired deposit.

[0019] As used herein, the term "substrate" may refer to any underlying material or materials that may be used or upon which a device, circuit or film may be formed.

[0020] The term "atomic layer deposition" (ALD) as used herein can refer to a vapor deposition process in which a deposition cycle, preferably multiple consecutive deposition cycles, are performed in a process chamber. Typically, during each cycle, a precursor chemisorbs to the deposition surface (e.g., the surface of a substrate or a surface of a previously deposited underlayer, such as a material deposited using a previous ALD cycle) and forms a monolayer or submonolayer that does not readily react with additional precursors (i.e., a self-limiting reaction). If necessary, a reactant (e.g., another precursor or a reactant gas) can then be introduced into the process chamber for use in converting the chemisorbed precursor to the desired material on the deposition surface. Typically, this reactant can further react with the precursor. Additionally, a purge step can be utilized during each cycle to remove excess precursor from the process chamber after conversion of the chemisorbed precursor and / or to remove excess reactants and / or reaction by-products from the process chamber. Additionally, the term "atomic layer deposition" as used herein is also meant to include processes indicated by related terms, such as, for example, "chemical vapor deposition atomic layer deposition," "atomic layer epitaxy" (ALE), molecular beam epitaxy (MBE), gas source MBE, or metalorganic MBE, as well as chemical beam epitaxy when performed with alternating pulses of precursor compositions, reactive gases, and purge (e.g., inert carrier) gases.

[0021] As used herein, the terms "film," "thin film," "layer," and "thin layer" are intended to mean any continuous or discontinuous structures and materials deposited by the methods disclosed herein. "Film," "thin film," "layer," and "thin layer" can include, for example, 2D materials, nanorods, nanotubes, nanolaminates, or nanoparticles, or partial or complete molecular layers, or partial or complete atomic layers, or clusters of atoms and / or molecules. "Film," "thin film," "layer," and "thin layer" can include materials or layers that have pinholes, but are still at least partially continuous.

[0022] As used herein, the term "transition metal-containing film" can refer to films that contain transition metal species, including, but not limited to, elemental transition metals, transition metal oxides, transition metal nitrides, transition metal silicides, transition metal selenides, transition metal phosphides, transition metal borides, and mixtures thereof. Additionally, the term "transition metal-containing film" can refer to films that contain transition metal species as well as carbon and / or hydrogen containing films.

[0023] It should be noted that many example materials are provided throughout the embodiments of this disclosure, and the chemical formulas provided for each of the example materials should not be construed as limiting, nor should the non-limiting example materials provided be limited by certain example stoichiometries.

[0024] The present disclosure includes methods for forming transition metal-containing films on a substrate, and specific methods for cyclic deposition of transition metal-containing films on a substrate. Embodiments of the present disclosure may include, for example, a method for cyclic deposition of a transition metal-containing film, such as a cobalt-containing film or a nickel-containing film.

[0025] Accordingly, embodiments of the present disclosure may include a method of forming a transition metal-containing film on a substrate by a cyclic deposition process. The method may include contacting the substrate with a first gas phase reactant comprising a transition metal halide compound comprising a bidentate nitrogen-containing additional ligand and contacting the substrate with a second gas phase reactant comprising a reducing agent precursor, wherein the transition metal-containing film has an electrical resistivity of less than 50 μΩ-cm at a film thickness of less than 50 nanometers.

[0026] In some embodiments of the present disclosure, transition metal-containing films can be deposited by a cyclic deposition process that utilizes a transition metal halide compound as a metal precursor. A non-limiting exemplary embodiment of the cyclic deposition process includes atomic layer deposition (ALD), which is based on a typical self-limiting reaction whereby sequential and alternating pulses of reactants are used to deposit approximately one atomic (or molecular) monolayer of material per deposition cycle. Deposition conditions and precursors are typically selected to provide a self-saturating reaction, such that an adsorbed layer of one reactant leaves a surface termination that is unreactive with the gas phase reactant of the same reactant. The substrate is then contacted with a different reactant that reacts with the previous termination, allowing for successive depositions. Thus, each cycle of alternating pulses typically leaves approximately one monolayer or less of the desired material. However, as noted above, one skilled in the art will recognize that more than one monolayer of material can be deposited in one or more ALD cycles, for example, if several gas phase reactions occur despite the nature of the alternating process.

[0027] In an ALD-type process for depositing a transition metal-containing film, one deposition cycle can include contacting a substrate with a first reactant, removing any unreacted first reactant and reaction by-products from the reaction space, and contacting the substrate with a second reactant, followed by a second removing step. The first reactant can include a transition metal halide compound ("metal precursor") and the second reactant can include a reducing agent precursor.

[0028] The precursors can be separated by an inert gas, such as argon (Ar) or nitrogen (N2), to prevent gas-phase reactions between the reactants and to allow self-saturating surface reactions. However, in some embodiments, the substrate can be moved to contact the first and second gas-phase reactants separately. Since the reaction is self-saturating, strict temperature control of the substrate and precise dosage control of the precursors may not be necessary. However, the substrate temperature is preferably such that the incident gas species do not condense into a monolayer and do not decompose at the surface. Before contacting the substrate with the next reactive chemical, excess chemicals and reaction by-products, if any, are removed from the substrate surface, for example by purging the reaction space or by moving the substrate. Undesired gas molecules can be effectively evacuated from the reaction space using an inert purge gas. A vacuum pump can be used to facilitate purging.

[0029] Any reactor that can be used to deposit transition metal-containing films can be used for deposition. Such reactors include ALD reactors equipped with appropriate devices and means for supplying precursors, as well as CVD reactors. According to some embodiments, showerhead reactors can be used. According to some embodiments, cross-flow, batch, mini-batch, or spatial ALD reactors can be used.

[0030] In some embodiments of the present disclosure, a batch reactor may be used. In some embodiments, the wafers are rotated during processing. In some embodiments, the batch reactor comprises a mini-batch reactor configured to accommodate 10 or fewer wafers, 8 or fewer wafers, 6 or fewer wafers, 4 or fewer wafers, or 2 or fewer wafers. In some embodiments where a batch reactor is used, the wafer-to-wafer non-uniformity is less than 3% (1 sigma), less than 2%, less than 1%, or even less than 0.5%.

[0031] The deposition methods described herein can be optionally performed in a reactor or reaction chamber connected to a cluster tool. In a cluster tool, the temperature of the reaction chambers in each module can be kept constant since each reaction chamber is dedicated to one type of process, improving throughput compared to reactors that heat the substrate to a process temperature before each run. Additionally, in a cluster tool, it is possible to reduce the time to evacuate the reaction chamber to the desired process pressure level between substrates. In some embodiments of the present disclosure, the deposition process can be performed in a cluster tool including multiple reaction chambers, each individual reaction chamber can be used to expose the substrate to an individual precursor gas, and the substrate can be transported between different reaction chambers to be exposed to multiple precursor gases, with the substrate transport being performed under a controlled ambient environment to avoid oxidation / contamination of the substrate. In some embodiments of the present disclosure, the deposition process can be performed in a cluster tool with multiple reaction chambers, each individual reaction chamber can be configured to heat the substrate to a different deposition temperature.

[0032] A stand-alone reactor is equipped with a load lock, in which case there is no need to cool the reaction space between each run. In some embodiments, the deposition process for deposition of transition metal-containing films can include multiple deposition cycles, such as ALD cycles or cyclic CVD cycles.

[0033] In some embodiments, a cyclic deposition process is used to form a transition metal-containing film on a substrate, and the cyclic deposition process can be an ALD-type process. In some embodiments, the cyclic deposition can be a hybrid ALD / CVD or cyclic CVD process. For example, in some embodiments, the growth rate of an ALD process can be low compared to a CVD process. One approach to increase the growth rate is to operate at a higher substrate temperature than typically used in an ALD process, resulting in a chemical vapor deposition process, but still utilizing sequential introduction of precursors, such a process can be referred to as cyclic CVD. In some embodiments, the cyclic CVD process can include the introduction of two or more precursors into a reaction chamber, with periods of overlap between the two or more precursors in the reaction chamber resulting in both the ALD component of the deposition and the CVD component of the deposition. For example, the cyclic CVD process can include a continuous flow of one precursor and periodic pulses of a second precursor into the reaction chamber.

[0034] According to some embodiments of the present disclosure, ALD processes can be used to deposit transition metal-containing films on substrates, such as partially fabricated semiconductor device structures. In some embodiments of the present disclosure, each ALD cycle includes two distinct deposition steps or phases. In the first phase of the deposition cycle (the "metal phase"), the surface of the substrate on which deposition is desired is contacted with a first gas-phase reactant that includes a metal precursor that chemisorbs onto the surface of the substrate and forms about one monolayer or less of the reactant species on the surface of the substrate. In the second phase of deposition, the substrate surface on which deposition is desired is contacted with a second gas-phase reactant that includes a reducing agent precursor, where the second gas-phase reactant can react with the transition metal species on the surface of the substrate to form a transition metal-containing film on the substrate, such as, for example, an elemental transition metal, or a transition metal nitride, or a mixture thereof.

[0035] In some embodiments of the present disclosure, the first gas phase reactant can include a metal-containing precursor, also referred to herein as a "metal compound." In some embodiments, the first gas phase reactant can include a transition metal compound having an adduct-forming ligand. In some embodiments, the first gas phase reactant can include a transition metal compound. In some embodiments, the first gas phase reactant can include a transition metal halide compound. In some embodiments, the first gas phase reactant can include a transition metal compound having an adduct-forming ligand, such as a monodentate, bidentate, or polydentate adduct-forming ligand. In some embodiments, the first gas phase reactant can include a transition metal halide compound having an adduct-forming ligand, such as a monodentate, bidentate, or polydentate adduct-forming ligand. In some embodiments, the first gas phase reactant can include a transition metal compound having a nitrogen-containing adduct-forming ligand, such as a nitrogen-containing monodentate, bidentate, or polydentate adduct-forming ligand. In some embodiments, the first gas phase reactant may include a transition metal compound having a phosphorous, oxygen, or sulfur-containing adduct forming ligand, such as a monodentate, bidentate, or polydentate adduct forming ligand including phosphorous, oxygen, or sulfur. For example, in some embodiments, the transition metal halide compound may include a transition metal chloride, a transition metal iodide, a transition metal fluoride, or a transition metal bromide. In some embodiments of the present disclosure, the transition metal halide compound may include a transition metal species including, but not limited to, at least one of cobalt or nickel. In some embodiments of the present disclosure, the transition metal halide compound may include at least one of cobalt chloride or nickel chloride. In some embodiments, the transition metal halide compound may include a bidentate nitrogen-containing adduct forming ligand. In some embodiments, the transition metal halide compound may include an adduct forming ligand including two nitrogen atoms, where each of the nitrogen atoms is bonded to at least one carbon atom. In some embodiments of the present disclosure, the transition metal halide compound includes one or more nitrogen atoms bonded to a central transition metal atom, thereby forming a metal complex.

[0036] In some embodiments of the present disclosure, the first vapor phase reactant may include a transition metal compound having the following formula (I): (adduct) n -MX a (I) wherein each of the "adducts" is an adduct-forming ligand, which may be independently selected to be a monodentate, bidentate, or polydentate adduct-forming ligand or mixtures thereof, where for monodentate forming ligands, n is 1-4, and for bidentate or polydentate adduct-forming ligands, n is 1-2, M is a transition metal, such as, for example, cobalt (Co) or nickel (Ni), and X a is another ligand, which can be independently selected to be a halide or other ligand, where a is 1-4, and in some examples, a is 2.

[0037] In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound, such as the transition metal halide compound, may include monodentate, bidentate, or polydentate adduct-forming ligands that are coordinated to the transition metal atom of the transition metal compound through at least one of a nitrogen atom, a phosphorous atom, an oxygen atom, or a sulfur atom. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include cycloaddition ligands. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include a monoamine, a diamine, or a polyamine. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include a monoether, a diether, or a polyether. In some embodiments, the adduct-forming ligands in the transition metal compound may include a monophosphine, a diphosphine, or a polyphosphine. In some embodiments, the adduct-forming ligands in the transition metal compound may include carbon in addition to nitrogen, oxygen, phosphorous, or sulfur in the adduct-forming ligand.

[0038] In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include one monodentate adduct-forming ligand. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include two monodentate adduct-forming ligands. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include three monodentate adduct-forming ligands. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include four monodentate adduct-forming ligands. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include one bidentate adduct-forming ligand. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include two bidentate adduct-forming ligands. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include one polydentate adduct-forming ligand. In some embodiments of the present disclosure, the adduct-forming ligands in the transition metal compound may include two polydentate adduct-forming ligands.

[0039] In some embodiments of the present disclosure, the adduct forming ligands include nitrogen, such as amine, diamine, or polyamine adduct forming ligands. In such embodiments, the transition metal compound may be selected from the group consisting of triethylamine (TEA), N,N,N',N'-tetramethyl-1,2-ethylenediamine (CAS: 110-18-9) (TMEDA), N,N,N',N'-tetraethylethylenediamine (CAS: 150-77-6) (TEEDA), N,N'-diethyl-1,2-ethylenediamine (CAS: 111-74-0) (DEEDA), N,N'-diisopropylethylenediamine (CAS: 4013-94-9), N,N,N',N'-tetramethyl-1,3-propanediamine (CAS: 110-95-2) (TMPDA), N,N,N',N'-tetramethylmethanediamine (CAS: 51-80-9) (TMMDA), N,N,N',N'',N''-pentamethyldiethylenetriamine (CAS: 30 30-47-5)(PMDETA), diethylenetriamine (CAS:111-40-0)(DIEN), triethylenetetramine (CAS:112-24-3)(TRIEN), tris(2-aminoethyl)amine (CAS:4097-89-6)(TREN, TAEA), 1,1,4,7,10,10-hexamethyltriethylenetetramine (CAS:3083-10-1)( HMTETA), 1,4,8,11-tetraazacyclotetradecane (CAS: 295-37-4) (Cyclam), 1,4,7-trimethyl-1,4,7-triazacyclononane (CAS: 96556-05-7), or 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane (CAS: 41203-22-9).

[0040] In some embodiments of the present disclosure, the adduct-forming ligand comprises a phosphorous acid, such as a phosphine, diphosphine, or polyphosphine adduct-forming ligand. For example, the transition metal compound may comprise at least one of triethylphosphine (CAS: 554-70-1), trimethylphosphite (CAS: 121-45-), 1,2-bis(diethylphosphino)ethane (CAS: 6411-21-8) (BDEPE), or 1,3-bis(diethylphosphino)propane (CAS: 29149-93-7).

[0041] In some embodiments of the present disclosure, the adduct-forming ligand comprises oxygen, such as an ether, diether, or polyether adduct-forming ligand. For example, the transition metal compound can comprise at least one of 1,4-dioxane (CAS: 123-91-1), 1,2-dimethoxyethane (CAS: 110-71-4) (DME, monoglyme), diethylene glycol dimethyl ether (CAS: 111-96-6) (diglyme), triethylene glycol dimethyl ether (CAS: 112-49-2) (triglyme), or 1,4,7,10-tetraoxacyclododecane (CAS: 294-93-9) (12-crown-4).

[0042] In some embodiments of the present disclosure, the adduct-forming ligand may include a thioether or mixed ether amine, such as at least one of 1,7-diaza-12-crown-4:1,7-dioxa-4,10-diazacyclododecane (CAS: 294-92-8), or 1,2-bis(methylthio)ethane (CAS: 6628-18-8).

[0043] In some embodiments, the transition metal halide compound may include cobalt chloride N,N,N',N'-tetramethyl-1,2-ethylenediamine (CoCl2(TMEDA)). In some embodiments, the transition metal halide compound may include cobalt bromide tetramethylethylenediamine (CoBr2(TMEDA)). In some embodiments, the transition metal halide compound may include cobalt iodide tetramethylethylenediamine (Col2(TMEDA)). In some embodiments, the transition metal halide compound may include cobalt chloride N,N,N',N'-tetramethyl-1,3-propanediamine (CoCl2(TMEDA)). In some embodiments of the present disclosure, the transition metal halide compound may include nickel chloride tetramethyl-1,3-propanediamine (NiCl2(TMPDA)), or nickel iodide tetramethyl-1,3-propanediamine (NiI2(TMPDA)).

[0044] In some embodiments of the present disclosure, contacting the substrate with a first gas phase reactant comprising a transition metal halide compound, i.e., a transition metal halide comprising an adduct-forming ligand, can include exposing the substrate to the transition metal halide compound, i.e., contacting the substrate for about 0.01 seconds to about 60 seconds, about 0.05 seconds to about 10 seconds, or about 0.1 seconds to about 5.0 seconds. In addition, during pulse injection of the transition metal halide compound, the flow rate of the transition metal halide compound can be less than 2000 sccm, or less than 500 sccm, or even 100 sccm. In addition, during pulse injection of the transition metal halide compound onto the substrate, the flow rate of the transition metal halide compound can vary from about 1 to 2000 sccm, from about 5 to 1000 sccm, or from about 10 to about 500 sccm.

[0045] Excess transition metal halide compounds and reaction by-products, if any, may be removed from the surface, for example, by pumping with an inert gas. For example, in some embodiments of the present disclosure, the method may include a purge cycle in which the surface of the substrate is purged for a time period of less than about 2.0 seconds. Excess transition metal halide compounds and reaction by-products may be removed using a vacuum generated by a pump system in fluid communication with the reaction chamber.

[0046] In a second stage of the deposition cycle, the substrate can be contacted with a second gas-phase reactant that includes a reducing agent precursor. In some embodiments, the second gas-phase reactant can include a reducing agent, and the transition metal-containing films deposited by the cyclic deposition methods disclosed herein can include elemental transition metals, or transition metal nitrides, or mixtures thereof.

[0047] In some embodiments of the present disclosure, the reducing agent precursor is hydrogen (H2), hydrogen (H2) plasma, ammonia (NH3), ammonia (NH3) plasma, hydrazine (N2H4), silane (SiH4), disilane (Si2H6), trisilane (Si3H8), germane (GeH4), digermane (Ge2H6), borane (BH3), diborane (B2H6), tertiary butyl hydrazine (C4H 12 The reducing agent precursor may include at least one of a hydrazine precursor, a selenium precursor, a boron precursor, a phosphorous precursor, a sulfur precursor, an organic precursor (e.g., an alcohol, an aldehyde, or a carboxylic acid), or a hydrogen precursor. In some embodiments, the reducing agent precursor may include a hydrazine or a substituted hydrazine precursor. In some embodiments, the reducing agent precursor, such as a substituted hydrazine precursor, may include tertiary butyl hydrazine (CH 12N2). In some embodiments of the present disclosure, the method can further include selecting the substituted hydrazine to include an alkyl group having at least 4 carbon atoms, where "alkyl group" refers to a saturated or unsaturated hydrocarbon chain of at least 4 carbon atoms in length, such as, but not limited to, butyl, pentyl, hexyl, heptyl, and octyl, and isomers thereof, such as, but not limited to, n-, iso-, sec-, and tert-isomers thereof. The alkyl group can be linear or branched and can include all structural isomeric forms of the alkyl group. In some embodiments, the alkyl chain can be substituted. In some embodiments of the present disclosure, the alkyl hydrazine can include at least one hydrogen bonded to the nitrogen. In some embodiments of the present disclosure, the alkyl hydrazine can include at least two hydrogens bonded to the nitrogen. In some embodiments of the present disclosure, the alkyl hydrazine can include at least one hydrogen bonded to the nitrogen and at least one alkyl chain bonded to the nitrogen. In some embodiments of the present disclosure, the reducing agent precursor may include an alkyl hydrazine and may further include one or more of tert-butyl hydrazine (C4H9N2H3), dimethyl hydrazine, or diethyl hydrazine. In some embodiments of the present disclosure, the substituted hydrazine has at least one hydrocarbon group bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine has at least two hydrocarbon groups bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine has at least three hydrocarbon groups bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine has at least one C1-C3 hydrocarbon group bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine has at least one C4-C10 hydrocarbon group bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine has a straight chain, branched chain, or cyclic or aromatic hydrocarbon group bonded to the nitrogen. In some embodiments of the present disclosure, the substituted hydrazine includes a substituted hydrocarbon group bonded to the nitrogen.

[0048] In some embodiments of the present disclosure, the substituted hydrazine has the formula: R I R II -N-NR III R IV (1) In the formula, R I can be selected from hydrocarbon groups, such as linear, branched, cyclic, aromatic or substituted hydrocarbon groups, and R II , R III , R IV Each of the groups can be independently selected to be a hydrogen group or a hydrocarbon group, such as a straight chain, branched chain, cyclic, aromatic or substituted hydrocarbon group.

[0049] In some embodiments, R in formula (1) I , R II , R III , R IV Each of the groups can be a C1-C10 hydrocarbon, a C1-C3 hydrocarbon, a C4-C10 hydrocarbon, or hydrogen, such as a straight chain, branched chain, cyclic, aromatic, or substituted hydrocarbon group. I , R II , R III , R IV At least one of the groups includes an aromatic group, such as a phenyl group. In some embodiments, R I , R II , R III , R IV At least one of the groups comprises a methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, tert-butyl group, or a phenyl group. I , R II , R III , R IV At least two of the groups can be independently selected to include a methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, tert-butyl group, or a phenyl group. II , R III and R IV In some embodiments, R II , RIII and R IV At least one of the two groups is hydrogen. In some embodiments, R II , R III and R IV At least one of the groups is hydrogen. In some embodiments, R II , R III and R IV All of the groups are hydrocarbons.

[0050] In some embodiments of the present disclosure, the reducing agent precursor may include organic compounds such as alcohols, aldehydes, or carboxylic acids, or other organic compounds may be utilized, such as organic compounds that do not have metals or metalloids, but do contain -OH groups. The alcohols can be primary alcohols, secondary alcohols, tertiary alcohols, polyhydroxy alcohols, cyclic alcohols, aromatic alcohols, and other derivatives of alcohols.

[0051] A primary alcohol has an -OH group attached to a carbon atom which is bonded to another carbon atom, in particular a primary alcohol according to the general formula (III). R1-OH (III) where R1 is a straight or branched C1-C20 alkyl or alkenyl group such as methyl, ethyl, propyl, butyl, pentyl or hexyl. Examples of primary alcohols include methanol, ethanol, propanol, butanol, 2-methylpropanol and 2-methylbutanol.

[0052] Secondary alcohols have an -OH group attached to a carbon atom that is bonded to two other carbon atoms. In particular, secondary alcohols have the following general formula (IV): [ka] wherein each R1 is independently selected from the group of linear or branched C1-C20 alkyl and alkenyl groups, such as methyl, ethyl, propyl, butyl, pentyl, or hexyl. Examples of secondary alcohols include 2-propanol and 2-butanol.

[0053] Tertiary alcohols have an -OH group attached to a carbon atom that is bonded to three other carbon atoms. In particular, tertiary alcohols have the following general formula (V): [ka] wherein each R1 is independently selected from the group of straight or branched C1-C20 alkyl and alkenyl groups, such as methyl, ethyl, propyl, butyl, pentyl, or hexyl. An example of a tertiary alcohol is tert-butanol.

[0054] Polyhydroxy alcohols, such as diols and triols, have primary, secondary and / or tertiary alcohol groups as described above. Examples of polyhydroxy alcohols are ethylene glycol and glycerol.

[0055] Cyclic alcohols have an --OH group attached to at least one carbon atom that is part of a ring of 1 to 10 carbon atoms, such as 5 to 6 carbon atoms.

[0056] Aromatic alcohols have at least one --OH group attached either to a benzene ring or to a carbon atom in a side chain.

[0057] The organic compound may contain at least one aldehyde group (-CHO) selected from the group consisting of compounds having the general formula (VI), alkanedial compounds having the general formula (VII), halogenated aldehydes and other derivatives of aldehydes.

[0058] Thus, in one embodiment, the organic compound is an aldehyde having the general formula (VI). R3-CHO (VI) wherein R3 is selected from the group consisting of hydrogen and linear or branched C1-C20 alkyl and alkenyl groups, such as methyl, ethyl, propyl, butyl, pentyl, or hexyl. In some embodiments, R3 is selected from the group consisting of methyl or ethyl. Exemplary compounds according to formula (VI) include, but are not limited to, formaldehyde, acetaldehyde, and butyraldehyde.

[0059] In another embodiment, the organic compound is an aldehyde having the general formula (VII). OHC-R4-CHO (VII) wherein R4 is a straight or branched chain C1-C20 saturated or unsaturated hydrocarbon. Alternatively, the aldehyde groups may be directly bonded to each other (R4 is null).

[0060] The organic compound containing at least one -COOH group may be selected from the group consisting of compounds of general formula (VIII), polycarboxylic acids, halogenated carboxylic acids and other derivatives of carboxylic acids.

[0061] Thus, in one embodiment, the organic compound is a carboxylic acid having the general formula (VIII). R5-COOH (VIII) wherein R5 is hydrogen or a linear or branched C1-C20 alkyl or alkenyl group such as methyl, ethyl, propyl, butyl, pentyl, or hexyl, e.g., methyl or ethyl. In some embodiments, R5 is a linear or branched C1-C3 alkyl or alkenyl group. Examples of compounds according to formula (VII) are formic acid, propanoic acid, and acetic acid, and in some embodiments, formic acid (HCOOH).

[0062] In some embodiments of the present disclosure, exposing or contacting the substrate with the second gas phase reactant may include pulsing the second gas phase reactant on the substrate for a time period between 0.1 seconds and 2.0 seconds, or between about 0.01 seconds and about 10 seconds, or less than about 20 seconds, less than about 10 seconds, or less than about 5 seconds. During pulsing of the second gas phase reactant on the substrate, the flow rate of the second gas phase reactant can be less than 50 sccm, or less than 25 sccm, or less than 15 sccm, or even less than 10 sccm.

[0063] For example, excess second gas phase reactant and reaction by-products, if any, may be removed from the surface of the substrate by pulses of purge gas and / or a vacuum created by an evacuation system. The purge gas is preferably any inert gas, such as, but not limited to, argon (Ar), nitrogen (N2), helium (He), or, in some cases, hydrogen (H2) may be used. One stage is generally considered to follow immediately after another stage if there is an intervening purge (i.e., purge gas pulse) or other reactant removal step.

[0064] The deposition cycle of alternately contacting the substrate with a first gas-phase reactant (i.e., a metal halide compound) and a second gas-phase reactant (e.g., a reducing agent precursor) may be repeated one or more times until a transition metal-containing film of a desired thickness is deposited. Of course, in some embodiments of the present disclosure, the order of contacting the substrate with the first and second gas-phase reactants may be such that the substrate is first contacted with the second gas-phase reactant followed by contact with the first gas-phase reactant. Furthermore, in some embodiments, the cyclic deposition process may include contacting the substrate with the first gas-phase reactant one or more times before contacting the substrate with the second gas-phase reactant one or more times, or equivalently, contacting the substrate with the second gas-phase reactant one or more times before contacting the substrate with the first gas-phase reactant one or more times.

[0065] Additionally, some embodiments of the present disclosure may be free of plasma reactants, e.g., the first and second gas phase reactants are substantially free of ionized reactants. In some embodiments, the first and second gas phase reactants are substantially free of ionized reactants, excited species, and radical species. For example, both the first and second gas phase reactants may be free of plasma reactants to prevent ionization damage of the underlying substrate and associated defects created thereby. The use of non-plasma reactants may be particularly useful when the underlying substrate includes fragile fabricated or at least partially fabricated semiconductor device structures, as energetic plasma species may damage and / or degrade performance characteristics of the device.

[0066] The cyclic deposition processes described herein utilizing a first gas phase reactant comprising a transition metal halide compound and a second gas phase reactant comprising a reducing agent precursor for depositing a transition metal-containing film may be carried out in an ALD or CVD deposition system using a heated substrate. For example, in some embodiments, the method may include heating the substrate to a temperature of about 150° C. to about 300° C., or further heating the substrate to a temperature of about 200° C. to about 250° C. Of course, the appropriate temperature window for any given cyclic deposition process, such as an ALD reaction, will depend on the surface termination and reactant species involved. Here, the temperature will vary depending on the precursors used and is generally about 700° C. or less. In some embodiments, for vapor deposition processes, the deposition temperature is generally about 100° C. or more, in some embodiments, the deposition temperature is about 100° C. to about 300° C., and in some embodiments, the deposition temperature is about 150° C. to about 250° C. In some embodiments, the deposition temperature is less than about 500° C., or less than about 400° C., or less than about 350° C., or less than about 300° C. In some embodiments, the deposition temperature may be less than about 300° C., or less than about 250° C., or less than about 200° C., or less than about 100° C. In some cases, the deposition temperature may be greater than about 20° C., greater than about 50° C., and greater than about 75° C. In some embodiments of the present disclosure, the deposition temperature, i.e., the temperature of the substrate during deposition, is about 250° C.

[0067] In some embodiments, the growth rate of the transition metal-containing film is about 0.005 Å / cycle to about 5 Å / cycle, about 0.01 Å / cycle to about 2.0 Å / cycle. In some embodiments, the growth rate of the transition metal-containing film is greater than about 0.05 Å / cycle, greater than about 0.1 Å / cycle, greater than about 0.15 Å / cycle, greater than about 0.20 Å / cycle, greater than about 0.25 Å / cycle, or greater than about 0.3 Å / cycle. In some embodiments, the growth rate of the transition metal-containing film is less than about 2.0 Å / cycle, less than about 1.0 Å / cycle, less than about 0.75 Å / cycle, less than about 0.5 Å / cycle, or less than 0.2 Å / cycle. In some embodiments of the present disclosure, the growth rate of the transition metal-containing film can be about 0.8 Å / cycle.

[0068] An embodiment of the present disclosure can include cyclic deposition, which can be illustrated in more detail by the exemplary cyclic deposition method 100 of FIG. 1. The method 100 can begin by process block 110, which includes providing at least one substrate into a reaction chamber and heating the substrate to a deposition temperature. For example, the substrate can include one or more partially fabricated semiconductor device structures, the reaction chamber can comprise an atomic layer deposition reaction chamber, and the substrate can be heated to a deposition temperature of less than about 300° C. In addition, the pressure in the reaction chamber can be controlled to reduce the atmosphere in the reaction chamber. For example, the pressure in the reaction chamber during the cyclic deposition process can be less than 1000 mbar, or less than 100 mbar, or less than 10 mbar, or less than 5 mbar, or even less than 1 mbar in some cases.

[0069] The exemplary method 100 may continue with process block 120, which includes contacting the substrate with a transition metal halide compound, for example, the substrate may be contacted with the transition metal halide compound for less than 2 seconds. In some embodiments of the present disclosure, the transition metal compound may contact the substrate for between about 0.01 seconds and about 60 seconds, between about 0.05 seconds and about 10 seconds, or between about 0.1 seconds and about 5 seconds. Furthermore, during pulse injection of the transition metal precursor onto the substrate, the flow rate of the transition metal precursor may be less than 2000 sccm, or less than 1000 sccm, or less than 500 sccm, or less than 200 sccm, or even less than 100 sccm.

[0070] Once the substrate is contacted with the transition metal halide compound, the excess metal precursor and any reaction by-products can be removed from the reaction chamber by a purge / evacuation process.

[0071] The method 100 may continue at process block 130 with contacting the substrate with a second vapor phase reactant comprising a reducing agent precursor. The second vapor phase reactant, for example, tertiary butyl hydrazine (CH 12 N2) may contact the substrate for approximately 4 seconds. In some embodiments of the present disclosure, the second gas phase reactant can contact the substrate for between about 0.01 seconds and about 60 seconds, or between about 0.05 seconds and about 10 seconds, or between about 0.1 seconds and about 5.0 seconds. Additionally, during pulsing of the second gas phase reactant on the substrate, the flow rate of the second gas phase reactant can be less than 2000 sccm, or less than 1000 sccm, or less than 500 sccm, or less than 200 sccm, or even less than 100 sccm.

[0072] Once the substrate has been contacted with the second gas phase reactant precursor, excess second gas phase reactant and any reaction by-products can be removed from the reaction chamber by a purge / evacuation process.

[0073] The exemplary cyclic deposition method 100, in which the substrate is alternately and sequentially contacted with a transition metal halide compound (process block 120) and a second vapor phase reactant (process block 130), may constitute one deposition cycle. In some embodiments of the present disclosure, the method of depositing a transition metal-containing film may include repeating the deposition cycle one or more times. For example, the method 100 may continue with a decision gate 140 that determines whether the cyclic deposition method 100 continues or ends via process block 150. The decision gate 140 is determined based on the thickness of the deposited transition metal-containing film, e.g., if the thickness of the transition metal-containing film is insufficient for the desired device structure, the method 100 may return to process block 120 and repeat the process of contacting the substrate with a transition metal halide compound and contacting the substrate with a second vapor phase reactant one or more times. Once the transition metal-containing film is deposited to a desired thickness, the method ends via process block 150, and the transition metal-containing film and the underlying semiconductor structure may undergo additional processes to form one or more device structures.

[0074] In some embodiments of the present disclosure, the transition metal-containing film formed by the methods disclosed herein can include elemental transition metal, transition metal nitride, or mixtures thereof. In some embodiments, the transition metal-containing film can include both elemental transition metal and transition metal nitride. In some embodiments, the transition metal-containing film can include both elemental nickel and nickel nitride. In some embodiments, the nickel nitride can include Ni6N2. In other embodiments, the transition metal-containing film can include both elemental cobalt and cobalt nitride. In some embodiments, the transition metal-containing film can consist essentially of elemental transition metal, such as, for example, nickel or cobalt.

[0075] In some embodiments of the present disclosure, the method of forming a transition metal-containing film may further include heating the transition metal-containing film after deposition, i.e., once the transition metal-containing film has been deposited to a desired thickness. For example, in some embodiments, the cyclic deposition method disclosed herein may be utilized to deposit a transition metal-containing film that includes both elemental transition metal and transition metal nitride. In such embodiments, a post-deposition heat treatment may be applied to the transition metal-containing film to reduce the transition metal nitride content in the deposited film to obtain a film that consists essentially of elemental transition metal. As a non-limiting example, the cyclic deposition method disclosed herein may be utilized to deposit a transition metal-containing film that includes both elemental nickel and nickel nitride, and a post-deposition heat treatment, i.e., thermal annealing of the transition metal-containing film, may result in a film that consists essentially of elemental nickel.

[0076] In some embodiments of the present disclosure, the post-deposition heating or annealing process may further include heating the deposited transition metal-containing film to a temperature less than 800° C., or less than 600° C., or less than 500° C., or even less than 400° C. In some embodiments, post-deposition heating of the transition metal-containing film may include heating the transition metal-containing film to a temperature between 800° C. and 400° C., or between 500° C. and 150° C., or even between 400° C. and 200° C.

[0077] In some embodiments of the present disclosure, a post-deposition heat treatment or annealing process can be performed in a reaction chamber having a selected atmosphere. In some embodiments, the post-deposition heat treatment can be performed in an inert atmosphere, such as, for example, a noble gas (e.g., He or Ar). In some embodiments, the post-deposition heat treatment can be performed in a reducing atmosphere, such as, for example, forming gas (N2+H2). In some embodiments of the present disclosure, the pressure in the reaction chamber during the post-deposition heat treatment can be adjusted to less than 100 Torr, or less than 1 Torr, or even less than 0.001 Torr.

[0078] The film or layer comprising a transition metal deposited according to some embodiments described herein may be a continuous thin film. In some embodiments, the thin film comprising a transition metal deposited according to some embodiments described herein may be continuous with a thickness of less than about 100 nanometers, or less than about 60 nanometers, or less than about 50 nanometers, or less than about 40 nanometers, or less than about 30 nanometers, or less than about 25 nanometers, or less than about 20 nanometers, or less than about 15 nanometers, or less than about 10 nanometers, or less than about 5 nanometers, or even less. The continuity referred to herein can be physical continuity or electrical continuity. In some embodiments, the thickness at which a film can be physically continuous may not be the same as the thickness at which a film is electrically continuous, and the thickness at which a film can be electrically continuous may not be the same as the thickness at which a film is physically continuous.

[0079] In some embodiments, the transition metal-containing films deposited according to some embodiments described herein can have a thickness of about 20 nanometers to about 100 nanometers. In some embodiments, the transition metal-containing films deposited according to some embodiments described herein can have a thickness of about 20 nanometers to about 60 nanometers. In some embodiments, the transition metal-containing films deposited according to some embodiments described herein can have a thickness of more than about 20 nanometers, or more than about 30 nanometers, or more than about 40 nanometers, or more than about 50 nanometers, or more than about 60 nanometers, or more than about 100 nanometers, or more than about 250 nanometers, or more than about 500 nanometers, or even more. In some embodiments, the transition metal-containing films deposited according to some embodiments described herein can have a thickness of less than about 50 nanometers, less than about 30 nanometers, less than about 20 nanometers, less than about 15 nanometers, less than about 10 nanometers, less than about 5 nanometers, less than about 3 nanometers, less than about 2 nanometers, or less than about 1 nanometer.

[0080] In some embodiments of the present disclosure, the transition metal-containing film may be deposited on three-dimensional structures, such as non-planar substrates including high aspect ratio features. In some embodiments, the step coverage of the transition metal-containing film may be about 50% or more, or about 80% or more, or about 90% or more, or about 95% or more, or about 98% or more, or about 99% or more, or more, in structures with aspect ratios (height / width) greater than about 2, greater than about 5, greater than about 10, greater than about 25, greater than about 50, or even greater than about 100.

[0081] In some embodiments of the present disclosure, the transition metal-containing film deposited according to embodiments of the present disclosure may contain less than about 50 atomic % oxygen, less than about 25 atomic % oxygen, less than about 10 atomic % oxygen, less than about 5 atomic % oxygen, less than about 2 atomic % oxygen, or even less than about 1 atomic % oxygen. In another embodiment, the transition metal-containing film may contain less than about 5 atomic % hydrogen, or less than about 2 atomic % hydrogen, or less than about 1 atomic % hydrogen, or even less than about 0.5 atomic % hydrogen. In yet another embodiment, the transition metal-containing film may contain less than about 5 atomic % carbon, or less than about 2 atomic % carbon, or less than about 1 atomic % carbon, or even less than about 0.5 atomic % carbon. In yet another embodiment, the transition metal-containing film may contain less than about 5 atomic % halide species, or less than about 2 atomic % halide species, or less than about 1 atomic % halide species, or even less than about 0.5 atomic % halide species. In some embodiments, the atomic % of the transition metal-containing material may be determined using Time of Flight Elastic Recoil Detection (ToF-ERDA) or X-ray Photoelectron Spectroscopy (XPS).

[0082] In some embodiments of the present disclosure, the transition metal-containing films deposited according to embodiments of the present disclosure can include both elemental transition metal and transition metal nitride. In such embodiments, the transition metal-containing films can include greater than 70 atomic % elemental transition metal, or greater than 80 atomic % elemental transition metal, or greater than 90 atomic % elemental transition metal. Further, in such embodiments, the transition metal-containing films can include less than 25 atomic % nitrogen, or less than 20 atomic % nitrogen, or even less than 15 atomic % nitrogen.

[0083] As a non-limiting example, Figure 2 shows X-ray photoelectron spectroscopy (XPS) data for a transition metal-containing film that includes both elemental nickel and nickel nitride. A review of Figure 2 shows that the exemplary film includes a nickel atomic % of about 80 atomic %. Further review of Figure 2 shows that the exemplary film includes a nitrogen atomic % of about 17 atomic % at the surface of the film and a nitrogen atomic % ranging from about 5 atomic % to about 12 atomic % within the bulk of the deposited film.

[0084] In some embodiments of the present disclosure, the transition metal-containing films deposited according to some embodiments described herein can have an electrical resistivity of less than 50 μΩ-cm at a film thickness of less than 50 nanometers, or less than 25 nanometers, or less than 10 nanometers. In some embodiments of the present disclosure, the transition metal-containing films deposited according to some embodiments described herein can have an electrical resistivity of less than 25 μΩ-cm at a film thickness of less than 50 nanometers, or less than 25 nanometers, or less than 10 nanometers. In some embodiments of the present disclosure, the transition metal-containing films deposited according to some embodiments described herein can have an electrical resistivity of less than 10 μΩ-cm at a film thickness of less than 50 nanometers, or less than 35 nanometers, or less than 10 nanometers.

[0085] In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than about 20 μΩ-cm at a thickness of less than 60 nanometers, or less than 50 nanometers, or less than 40 nanometers, or less than 30 nanometers, or less than 25 nanometers, or less than 20 nanometers, or less. In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than about 15 μΩ-cm at a thickness of less than 60 nanometers, or less than 50 nanometers, or less than 40 nanometers, or less than 30 nanometers, or less than 25 nanometers, or even less than 10 nanometers, or less. In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than about 10 μΩ-cm at a thickness of less than 60 nanometers, or less than 50 nanometers, or less than 40 nanometers, or less than 30 nanometers, or less than 25 nanometers, or less than 20 nanometers, or less.

[0086] In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than 10 μΩ-cm at a thickness of less than 35 nanometers. In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than 15 μΩ-cm at a thickness of less than 15 nanometers.

[0087] In some embodiments, the deposited transition metal-containing film can have an electrical resistivity of less than 200 μΩ-cm, or less than 100 μΩ-cm, or less than 50 μΩ-cm, or less than 30 μΩ-cm, or less than 20 μΩ-cm, or less than 18 μΩ-cm, or less than 15 μΩ-cm, or less than 12 μΩ-cm, or less than 10 μΩ-cm, or less than 8 μΩ-cm, at a film thickness of less than 100 nanometers.

[0088] In some embodiments, the deposited transition metal-containing film can include both elemental nickel and nickel nitride, and in such embodiments, the transition metal-containing film can have an electrical resistivity of less than 200 μΩ-cm, or less than 100 μΩ-cm, or less than 50 μΩ-cm, or less than 30 μΩ-cm, or less than 20 μΩ-cm, or less than 18 μΩ-cm, or less than 15 μΩ-cm, or less than 12 μΩ-cm, or less than 10 μΩ-cm, or less than 8 μΩ-cm, or less than 5 μΩ-cm, or lower, at a thickness of less than about 100 nanometers. Further, in such embodiments, the transition metal-containing film can have an electrical resistivity of less than 20 μΩ-cm, or less than 18 μΩ-cm, or less than 15 μΩ-cm, or less than 12 μΩ-cm, or less than 10 μΩ-cm, or less than 8 μΩ-cm, or less than 5 μΩ-cm, or lower, at a thickness of less than 50 nanometers. Further, in such embodiments, the transition metal-containing film can have an electrical resistivity of less than 4 μΩ-cm, or an electrical resistivity of less than 3 μΩ-cm, or even an electrical resistivity of less than 2 μΩ-cm. As a non-limiting example, a transition metal-containing film deposited by the methods of the present disclosure to a thickness of about 50 nanometers includes both elemental nickel and nickel nitride with an electrical resistivity of less than about 10 μΩ-cm.

[0089] In some embodiments, the deposited transition metal-containing film can include both elemental cobalt and cobalt nitride, and in such embodiments, the transition metal-containing film can have an electrical resistivity of less than about 200 μΩ-cm, or less than about 100 μΩ-cm, or less than about 50 μΩ-cm, or less than about 30 μΩ-cm, or less than about 20 μΩ-cm, or less than about 18 μΩ-cm, or less than about 15 μΩ-cm, or less than about 12 μΩ-cm, or less than about 10 μΩ-cm, or less than about 8 μΩ-cm, or less than about 5 μΩ-cm, at a film thickness of less than about 100 nanometers. Further, in such embodiments, the transition metal-containing film can have an electrical resistivity of less than about 20 μΩ-cm, or less than about 18 μΩ-cm, or less than about 15 μΩ-cm, or less than about 12 μΩ-cm, or less than about 10 μΩ-cm, or less than about 8 μΩ-cm, or less than about 5 μΩ-cm, or lower, at a film thickness of less than about 50 nanometers. Further, in such embodiments, the transition metal-containing film can have an electrical resistivity of less than 4 μΩ-cm, or less than 3 μΩ-cm, or even less than 2 μΩ-cm. As a non-limiting example, transition metal-containing films deposited by the methods of the present disclosure to a thickness of less than 50 nanometers and containing both elemental cobalt and cobalt nitride have an electrical resistivity of less than 10 μΩ-cm.

[0090] The exemplary embodiments of the present disclosure described above are merely examples of embodiments of the present invention, as defined by the appended claims and their legal equivalents, and therefore do not limit the scope of the present invention. Any equivalent embodiments are intended to be within the scope of the present invention. Indeed, various modifications of the present disclosure in addition to those shown and described herein may become apparent to those skilled in the art from the description, such as alternative useful combinations of the described elements. Such modifications and embodiments are also intended to fall within the scope of the appended claims.

[0091] [1] A method for forming a transition metal-containing film on a substrate by a cyclic deposition process, comprising: contacting the substrate with a first gas phase reactant comprising a transition metal halide compound comprising a bidentate nitrogen-containing additional ligand; contacting the substrate with a second gas phase reactant comprising a reducing agent precursor; The method of claim 1, wherein the transition metal-containing film has an electrical resistivity of less than 50 μΩ-cm at a thickness of less than 50 nanometers. [2] The method of [1], wherein the additional ligand comprises two nitrogen atoms, each of which is bonded to at least one carbon atom. [3] The method of [1], wherein the transition metal halide compound comprises a transition metal chloride. [4] The method according to [3], wherein the transition metal chloride compound comprises at least one of cobalt chloride or nickel chloride. [5] The method of [4], wherein the transition metal chloride compound comprises at least one of cobalt chloride (TMEDA) or nickel chloride (TMPDA). [6] The reducing agent precursor is tertiary butyl hydrazine (CH 12 2. The method of claim 1, wherein the catalytic converter is selected from the group including silane (SiH4), disilane (Si2H6), trisilane (Si3H8), germane (GeH4), digermane (Ge2H6), borane (BH3), or diborane (B2H6). [7] The reducing agent precursor is tertiary butyl hydrazine (CH 12 The method according to claim 6, further comprising: [8] The method of [1], wherein the transition metal-containing film comprises both an elemental transition metal and a transition metal nitride. [9] The method of [8], wherein the transition metal-containing film comprises both elemental nickel and nickel nitride.

[10] The method of [9], wherein the nickel nitride comprises Ni6N2.

[11] The method of [8], wherein the transition metal-containing film comprises both elemental cobalt and cobalt nitride.

[12] The method of [1], wherein the cyclic deposition process comprises an atomic layer deposition process.

[13] The method of [1], wherein the cyclic deposition process comprises a cyclic chemical vapor deposition process.

[14] The method of [1], wherein the transition metal-containing film has an electrical resistivity of less than 10 μΩ-cm at a thickness of less than 35 nanometers.

[15] The method of [1], wherein the transition metal-containing film has an electrical resistivity of less than 15 μΩ-cm at a thickness of less than 15 nanometers.

[16] The method of [1], further comprising heating the substrate to a temperature less than 250°C.

[17] The method of [1], further comprising heating the transition metal-containing film after deposition.

[18] The method of

[17] , wherein the transition metal-containing film is heated to a temperature less than 800° C.

[19] The method according to [1], wherein the reducing agent precursor is selected from the group including substituted hydrazines.

[20] The method according to [1], wherein the reducing agent precursor is selected from the group including alkyl-hydrazines.

Claims

[Claim 1] 1. A method for forming a transition metal-containing film on a substrate by a cyclic deposition process, comprising: contacting the substrate with a first vapor phase reactant comprising a transition metal halide compound comprising a bidentate nitrogen-containing additional ligand; contacting the substrate with a second gas phase reactant comprising a reducing agent precursor; the transition metal-containing film has an electrical resistivity of less than 50 μΩ-cm at a thickness of less than 50 nanometers; The reducing agent precursor is tertiary butyl hydrazine (C ４ H １２ N ２ ) or hydrogen (H ２ ).

Images