Transition Metal Nitride Deposition Method

Abstract

The present disclosure relates to methods and apparatus for depositing materials containing transition metal nitrides on substrates in the field of manufacturing semiconductor devices. The method according to the present disclosure includes a cyclic deposition process, wherein a substrate is provided in a reaction chamber, an organic metal transition metal precursor is provided to the reaction chamber in a gas phase, and a nitrogen precursor is provided to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. The present disclosure also relates to transition metal nitride layers, semiconductor structures and devices, and deposition assemblies for depositing transition metal nitrides on substrates.

Description

Technical Field

[0001] The present disclosure relates to methods and apparatus for fabricating semiconductor devices. More particularly, the present disclosure relates to methods and systems for depositing metal nitride-containing materials on substrates and layers containing metal nitrides. Background Art

[0002] Semiconductor device manufacturing processes often use advanced deposition methods to form metal-containing layers with specific properties. Transition metal nitrides from Group 4 (titanium, zirconium, hafnium), Group 5 (vanadium, niobium, tantalum), and Group 6 (chromium, molybdenum, and tungsten) are potentially useful for a range of semiconductor applications. In particular, these materials have been proposed for back-end-of-line (BEOL) barrier and liner applications where low resistivity is important. In addition, many applications require low-temperature deposition of these materials, typically 350°C or less, due to integration thermal budget constraints. Molybdenum nitride-containing materials, in particular, are often deposited at temperatures that are incompatible with BEOL applications.

[0003] Furthermore, methods that avoid fluorine (F) or chlorine (Cl) are preferred over methods that use these elements in precursors or co-reactants. Unfortunately, most methods that avoid F and Cl are based on metal organic or organometallic precursors that contain carbon, which is incorporated into the film in significant concentrations and serves to increase resistivity. The present invention provides a low temperature ALD route that is free of F and Cl to obtain low resistivity metal nitride films with low carbon content.

[0004] Any discussion set forth in this section (including discussion of problems and solutions) has been included in the present disclosure merely to provide context for the present disclosure. Such discussion should not be construed as an admission that any or all information was known at the time the present invention was made, or constitutes prior art. Summary of the invention

[0005] This Summary may introduce some concepts in a simplified form that are further described below. This Summary is not intended to necessarily 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.

[0006] Various embodiments of the present disclosure relate to methods of depositing transition metal nitride-containing materials on substrates, transition metal nitride layers, semiconductor structures and devices, and deposition assemblies for depositing transition metal nitride-containing materials on substrates.

[0007] In one aspect, a method for depositing a material containing a transition metal nitride on a substrate by a cyclic deposition process is disclosed. The method includes providing a substrate in a reaction chamber, providing an organometallic transition metal precursor to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. In the method, the transition metal precursor includes a transition metal from any one of Groups 4 to 6 of the periodic table.

[0008] In some embodiments, the transition metal precursor comprises a transition metal of Group 6 according to the periodic table. In some embodiments, the transition metal of Group 6 is selected from molybdenum and tungsten. In some embodiments, the transition metal of Group 6 is molybdenum. In some embodiments, the transition metal precursor comprises only molybdenum, carbon and hydrogen. In some embodiments, the transition metal precursor comprises bis(ethylbenzene) molybdenum. In some embodiments, the transition metal precursor comprises benzene or cyclopentadienyl. In some embodiments, the nitrogen precursor comprises only nitrogen and hydrogen. In some embodiments, the nitrogen precursor is selected from a mixture of NH3, NH2NH2 and gaseous H2 and N2.

[0009] In some embodiments, the method according to the present disclosure also includes providing an auxiliary reactant to the reaction chamber in a gas phase. In some embodiments, the auxiliary reactant includes a halogen selected from bromine and iodine. In some embodiments, the auxiliary reactant includes an organic group. In some embodiments, the auxiliary reactant includes a halogenated hydrocarbon. In some embodiments, the auxiliary reactant includes two or more halogen atoms. In some embodiments, at least two halogen atoms are connected to different carbon atoms. In some embodiments, two halogen atoms in the auxiliary reactant are connected to adjacent carbon atoms of the carbon chain. In some embodiments, the auxiliary reactant includes 1,2-dihaloalkane or 1,2-dihaloalkene or 1,2-dihaloalkyne or 1,2-dihaloaromatic hydrocarbon. In some embodiments, the two halogen atoms of the auxiliary reactant are the same halogen. In some embodiments, the auxiliary reactant includes 1,2-diiodoethane. In some embodiments, the auxiliary reactant is used to adjust the resistivity of the deposited transition metal nitride material.

[0010] In some embodiments, the auxiliary reactant comprises a Group 14 element selected from Si, Ge, or Sn. In some embodiments, the auxiliary reactant has the general formula R a MX b or R c X d M—MR c X d , wherein a is 0, 1, 2 or 3, b is 4-a, c is 0, 1 or 2, d is 3-c, R is a hydrocarbon, M is Si, Ge or Sn, and each X is independently any ligand. In some embodiments, X in the auxiliary reactant is hydrogen, substituted or unsubstituted alkyl or aryl or halogen. In some embodiments, the cyclic deposition process includes a thermal deposition process.

[0011] In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the transition metal precursor into the reaction chamber. In some embodiments, the transition metal nitride is deposited as a layer on the substrate.

[0012] On the other hand, a transition metal nitride layer produced by a cyclic deposition process is disclosed. The method includes providing a substrate in a reaction chamber, providing a transition metal precursor to the reaction chamber in a gas phase; and providing an auxiliary reactant to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. The transition metal precursor in the method includes a transition metal from any one of Groups 4 to 6 of the periodic table. In some embodiments, the transition metal nitride layer according to the present disclosure has a resistivity of less than about 600 μΩ·cm. In some embodiments, the transition metal nitride layer according to the present disclosure has a carbon content of less than about 20 atomic %.

[0013] In one aspect, a semiconductor structure comprising a transition metal nitride deposited by a cyclic deposition process is disclosed. The method comprises providing a substrate in a reaction chamber, providing a transition metal precursor to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. In the method, the transition metal precursor comprises a transition metal from any one of Groups 4 to 6 of the periodic table. Thus, a semiconductor structure comprising a transition metal nitride deposited according to the method of the present disclosure is disclosed.

[0014] In another aspect, a semiconductor device comprising a transition metal nitride deposited by a cyclic deposition process is disclosed. The method comprises providing a substrate in a reaction chamber, providing a transition metal precursor to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. In the method, the transition metal precursor comprises a transition metal from any one of Groups 4 to 6 of the periodic table. Thus, a semiconductor device comprising a transition metal nitride deposited according to the method of the present disclosure is disclosed.

[0015] In another aspect, a deposition assembly for depositing a material containing a transition metal nitride on a substrate is disclosed, the deposition assembly comprising one or more reaction chambers and a precursor injector system, the reaction chamber being constructed and arranged to hold a substrate, the precursor injector system being constructed and arranged to provide a transition metal precursor, an auxiliary reactant, and a nitrogen precursor to the reaction chamber in a gas phase. The deposition assembly also comprises a precursor container, the precursor container being constructed and arranged to contain a transition metal precursor, the transition metal precursor comprising a transition metal from any one of Groups 4 to 6 of the periodic table, and the assembly being constructed and arranged to provide the transition metal precursor, the auxiliary reactant, and the nitrogen precursor to the reaction chamber through the precursor injector system to deposit the material containing a transition metal nitride on the substrate.

[0016] In the present disclosure, any two numbers of a variable may constitute a feasible range for the variable, and any range indicated may include or exclude endpoints. In addition, any values ​​of the indicated variables (regardless of whether they are expressed as "about") may refer to exact values ​​or approximate values, and include equivalents, and may refer to average values, median values, representative values, majority values, etc. In addition, in the present disclosure, the terms "including", "consisting of" and "having" independently refer to "generally or broadly including", "including", "essentially consisting of" or "consisting of" in some embodiments. In the present disclosure, in some embodiments, the meaning of any definition does not necessarily exclude the common and customary meanings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are included to provide a further understanding of the present disclosure and constitute a part of this specification, illustrate exemplary embodiments and together with the description help to explain the principles of the present disclosure. In the drawings:

[0018] Figures 1A-1D is a block diagram of an exemplary embodiment of a method according to the present invention.

[0019] Figure 2 is a schematic diagram of a transition metal nitride layer deposited according to the present invention.

[0020] Figure 3 is a schematic diagram of a deposition assembly according to the present invention. DETAILED DESCRIPTION

[0021] The descriptions of exemplary embodiments of methods, structures, devices, and deposition assemblies provided below are merely exemplary and are for illustrative purposes only. The following description is not intended to limit the scope of the present disclosure or the claims. In addition, the description of multiple embodiments having the features shown is not intended to exclude other embodiments having additional features or other embodiments incorporating different combinations of the features. For example, various embodiments are set forth as exemplary embodiments and may be described in dependent claims. Unless otherwise stated, the exemplary embodiments or parts thereof may be combined or may be applied separately from each other. The headings provided here, if any, are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.

[0022] Overall process

[0023] In one aspect, a method for depositing a transition metal nitride-containing material on a substrate by a cyclic deposition process is disclosed. As used herein, the term "transition metal nitride-containing material" may refer to a material comprising at least a transition metal component and a nitrogen component. The formal oxidation state of the nitrogen may be -3.

[0024] The transition metal in the transition metal is selected from Groups 4, 5 and 6 of the periodic table. Therefore, in some embodiments, the transition metal nitride according to the present disclosure is titanium nitride. In some embodiments, the transition metal nitride according to the present disclosure is zirconium nitride. In some embodiments, the transition metal nitride according to the present disclosure is hafnium nitride. In some embodiments, the transition metal nitride according to the present disclosure is vanadium nitride. In some embodiments, the transition metal nitride according to the present disclosure is niobium nitride. In some embodiments, the transition metal nitride according to the present disclosure is tantalum nitride. In some embodiments, the transition metal nitride according to the present disclosure is chromium nitride. In some embodiments, the transition metal nitride according to the present disclosure is molybdenum nitride. In some embodiments, the transition metal nitride according to the present disclosure is tungsten nitride.

[0025] Transition metal nitride layer

[0026] In some embodiments, the transition metal nitride is deposited as a layer on the substrate. In such embodiments, the transition metal nitride forms a transition metal nitride layer. As used herein, a "transition metal nitride layer" may be a material layer comprising a transition metal and nitrogen, and they exist at least in part as a transition metal nitride. In some embodiments, the transition metal and nitrogen exist primarily as transition metal nitrides. For example, in some embodiments, at least 30% of the nitrogen in the transition metal nitride layer is a nitride. In some embodiments, at least 50% of the nitrogen in the transition metal nitride layer is a nitride. In some embodiments, at least 70% of the nitrogen in the transition metal nitride layer is a nitride. In some embodiments, at least 90% of the nitrogen in the transition metal nitride layer is a nitride. In some embodiments, at least 95% of the nitrogen in the transition metal nitride layer is a nitride.

[0027] As used herein, the terms "layer" and / or "film" may refer to any continuous or discontinuous structure and material, such as materials deposited by the methods disclosed herein. For example, a layer and / or film may include a two-dimensional material, a three-dimensional material, nanoparticles, or even a partial or complete molecular layer or a partial or complete atomic layer or atom and / or molecular cluster. A film or layer may include a material or layer having pinholes, which may be at least partially continuous. A seed layer may be a discontinuous layer used to increase the nucleation rate of another material. However, a seed layer may also be substantially or completely continuous.

[0028] Without limiting the present disclosure to any particular theory, in some embodiments, it is possible to produce a transition metal nitride layer with a low resistivity. The resistivity of the transition metal nitride layer according to the present disclosure can be less than about 600 μΩ·cm. In some embodiments, the resistivity of the transition metal nitride layer is less than about 500 μΩ·cm, such as about 400 μΩ·cm. In some embodiments, the resistivity of the transition metal nitride layer is less than about 300 μΩ·cm, such as 250 μΩ·cm. In some embodiments, the resistivity of the transition metal nitride layer is less than about 200 μΩ·cm, such as 170 μΩ·cm.

[0029] In some embodiments, the transition metal nitride layer may include, for example, about 60 to about 99 atomic percent (atomic %) transition metal and nitrogen, or about 75 to about 99 atomic % transition metal and nitrogen, or about 75 to about 95 atomic % transition metal and nitrogen, or about 75 to about 89 atomic % transition metal and nitrogen. The transition metal nitride layer deposited by the method according to the present disclosure may include, for example, about 80 atomic %, about 83 atomic %, about 85 atomic %, about 87 atomic %, about 90 atomic %, about 95 atomic %, about 97 atomic % or about 99 atomic % transition metal and nitrogen. In some embodiments, the transition metal nitride layer may be substantially composed of or composed of transition metal nitride. The layer composed of transition metal nitride may include an acceptable amount of impurities, such as oxygen, carbon, chlorine or other halogens and / or hydrogen, which may be derived from one or more precursors used to deposit the transition metal nitride layer. However, in some embodiments, the transition metal nitride layer may substantially contain only transition metal and nitrogen, and substantially all nitrogen is in the form of nitride. Thus, the transition metal layer may include, consist essentially of, or consist of a transition metal nitride. In some embodiments, the transition metal nitride layer may be a seed layer. The seed layer may be used to enhance the deposition of another layer. In some embodiments, the transition metal nitride layer is a barrier layer.

[0030] In some embodiments, the transition metal nitride layer may include less than about 35 atomic %, less than about 30 atomic %, less than about 20 atomic %, less than about 10 atomic %, less than about 8 atomic %, less than about 7 atomic %, less than about 5 atomic %, or less than about 2 atomic % oxygen. In some embodiments, the transition metal nitride layer may include less than about 20 atomic %, less than about 15 atomic %, less than about 10 atomic %, less than about 8 atomic %, less than about 5 atomic %, or less than about 3 atomic % carbon.

[0031] Substrate

[0032] The deposition method according to the present invention includes providing a substrate in a reaction chamber. The substrate can be any one or more underlying materials that can be used to form or on which a structure, device, circuit or layer can be formed. The substrate can include bulk materials, such as silicon (e.g., single crystal silicon), other Group IV materials, such as germanium, or other semiconductor materials, such as Group II-VI or Group III-V semiconductor materials, and can include one or more layers covering or located below the bulk material. In addition, the substrate can include various features, such as depressions, protrusions, etc. formed in or on at least a portion of the substrate layer. For example, the substrate can include a bulk semiconductor material and an insulating or dielectric material layer covering at least a portion of the bulk semiconductor material. The substrate can include nitrides such as TiN, oxides, insulating materials, dielectric materials, conductive materials, metals such as tungsten, ruthenium, molybdenum, cobalt, aluminum or copper, or metallic materials, crystalline materials, epitaxial materials, heteroepitaxial materials and / or single crystal materials. In some embodiments currently disclosed, the substrate includes silicon. As described above, in addition to silicon, the substrate can include other materials. Other materials can form layers. Specifically, the substrate can include a partially manufactured semiconductor device.

[0033] Reaction Chamber

[0034] The method of depositing transition metals according to the present invention includes providing a substrate in a reaction chamber. In other words, the substrate is brought into a space where the deposition conditions can be controlled. The reaction chamber can be part of a combination tool in which different processes are performed to form an integrated circuit. In some embodiments, the reaction chamber can be a flow-type reactor, such as a cross-flow reactor. In some embodiments, the reaction chamber can be a showerhead reactor. In some embodiments, the reaction chamber can be a spatially separated reactor. In some embodiments, the reaction chamber can be a single wafer ALD reactor. In some embodiments, the reaction chamber can be a single wafer ALD reactor for large-scale manufacturing. In some embodiments, the reaction chamber can be a batch reactor for simultaneously manufacturing multiple substrates.

[0035] Furthermore, in the method according to the present disclosure, the organometallic transition metal precursor is provided in a gas phase into the reaction chamber, and the nitrogen precursor is provided in a gas phase into the reaction chamber to form a transition metal nitride on the substrate.

[0036] In the method according to the present disclosure, when the transition metal precursor is in the reaction chamber, it can be in the gas phase. The transition metal precursor can be partially gaseous or liquid, or even solid at some time point before being provided in the reaction chamber. In other words, the transition metal precursor can be solid, liquid or gas, such as in a precursor container or other holding portion before being transported to the reaction chamber. When the precursor is transported to the reaction chamber, various methods can be used to make the precursor gas phase. Such a device can include, for example, a heater, a vaporizer, a gas flow or applying a low pressure or any combination thereof. Therefore, the method according to the present disclosure can include heating the transition metal precursor before the transition metal precursor is provided to the reaction chamber. In some embodiments, the transition metal precursor is heated to at least 60°C, at least 100°C, or at least 110°C, or at least 120°C, or at least 130°C or at least 140°C in the container. In some embodiments, the transition metal precursor is heated to at most 160° C., or at most 140° C., or at most 120° C., or at most 100° C., or at most 80° C., or at most 60° C. The injector system may also be heated to improve gas phase delivery of the transition metal precursor to the reaction chamber.

[0037] In the present disclosure, "gas" may include materials that are gaseous at normal temperature and pressure (NTP), evaporated solids and / or evaporated liquids, and may be composed of a single gas or a gas mixture as appropriate. The transition metal precursor may be provided to the reaction chamber in a gas phase. The term "inert gas" may refer to a gas that does not participate in a chemical reaction and / or does not become part of a layer to a perceptible degree. Exemplary inert gases include He and Ar and any combination thereof. In some cases, molecular nitrogen and / or hydrogen may be an inert gas. Gases other than process gases, i.e., gases not introduced by a precursor injector system, other gas distribution devices, etc., may be used, for example, to seal the reaction space and may include sealing gases.

[0038] In the method according to the present disclosure, the nitrogen precursor may be contacted with a substrate comprising a chemisorbed transition metal precursor. The conversion of the transition metal precursor to a transition metal nitride may occur on the substrate surface. In some embodiments, the conversion may be at least partially carried out in a gas phase. In some embodiments, an auxiliary reactant may be contacted with a substrate comprising a chemisorbed transition metal precursor. Contacting the substrate comprising a chemisorbed transition metal precursor with the auxiliary reactant may occur before or after contacting the substrate comprising a chemisorbed transition metal precursor with the nitrogen precursor. Without limiting the present invention to any particular theory, the auxiliary reactant may form an intermediate substance that affects the formation of a transition metal nitride on the substrate surface. In some embodiments, the auxiliary reactant includes a bond that may be broken to produce an intermediate substance, wherein the transition metal precursor is chemically adsorbed onto the substrate. Without limiting the present disclosure to any particular theory, the auxiliary reactant may form two monoanionic substances, both of which are connected to the transition metal precursor chemically adsorbed onto the substrate, which may change the formal oxidation state of the transition metal and cause the release of one or more groups connected thereto. The release may be carried out through an intermediate step. In some embodiments, the bond that may be broken is a bond between a Group 14 element and a halogen. In some embodiments, the bond that may break is a carbon-halogen bond. In some embodiments, the bond that may break is a bond between two halogen atoms. Halogen can be the same or different elements. In some embodiments, the bond that may break is a bond between two atoms of the 14th group element. The 14th group element can be the same or different elements. For example, the bond that may break can be a C-Br bond, or a CI bond, or a Br-Br bond, or a II bond, or a C-Si bond, or a C-Ge bond, or a Si-Si bond, or a Ge-Ge bond.

[0039] Cyclic deposition process

[0040] In the present disclosure, a deposition process may include a cyclic deposition process, such as an atomic layer deposition (ALD) process or a cyclic chemical vapor deposition (cyclic CVD) process. The term "cyclic deposition process" may refer to the sequential introduction of precursors and / or reactants into a reaction chamber to deposit materials, such as transition metals, on a substrate. Cyclic deposition includes processing techniques such as atomic layer deposition (ALD), cyclic chemical vapor deposition (cyclic CVD), and a hybrid cyclic deposition process including an ALD component and a cyclic CVD component. The process may include a purge step between providing precursors or between providing precursors and reactants in a reaction chamber.

[0041] The process may include one or more cyclic phases. For example, pulses of transition metal and nitrogen precursors may be repeated. In some embodiments, the process includes one or more non-cyclic phases. In some embodiments, the deposition process includes a continuous flow of at least one precursor. In some embodiments, a reactant may be provided continuously in the reaction chamber. In such embodiments, the process includes a continuous flow of a precursor or reactant. In some embodiments, one or more precursors and / or reactants are provided continuously in the reaction chamber. In some embodiments, an auxiliary reactant may be provided continuously in the reaction chamber.

[0042] The term "atomic layer deposition" (ALD) may refer to a vapor deposition process in which a deposition cycle (e.g., multiple consecutive deposition cycles) is performed in a reaction chamber. The term atomic layer deposition as used herein is also meant to include processes designated by related terms, such as chemical vapor atomic layer deposition, when performed with alternating pulses of precursor / reactant and optional purge gas. Typically, for an ALD process, during each cycle, a precursor is introduced into the reaction chamber and chemically adsorbed onto a deposition surface (e.g., a substrate surface that may include previously deposited material or other material from a previous ALD cycle), forming a monolayer or sub-monolayer of a material that is not easily reacted with additional precursors (i.e., a self-limiting reaction). Thereafter, in some cases, another precursor or reactant may subsequently be introduced into the processing chamber for converting the chemically adsorbed precursor into a desired material on the deposition surface. The second precursor or reactant is capable of further reacting with the precursor. During one or more cycles, such as during each step of each cycle, a purge step may be utilized to remove any excess precursor from the processing chamber and / or remove any excess reactant and / or reaction byproducts from the reaction chamber. Thus, in some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the transition metal precursor into the reaction chamber. In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the nitrogen precursor into the reaction chamber. In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the auxiliary reactant into the reaction chamber. In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the transition metal precursor into the reaction chamber and after providing the nitrogen precursor into the reaction chamber and providing the auxiliary reactant into the reaction chamber.

[0043] CVD type process generally involves gas phase reaction between two or more precursors and / or reactants. Precursors and reactants can be provided to reaction space or substrate simultaneously, or provided with partially or completely separated pulses. Substrate and / or reaction space can be heated to promote the reaction between gaseous precursors and / or reactants. In certain embodiments, precursors and reactants are provided until a layer with a desired thickness is deposited. In certain embodiments, a cyclic CVD process can use multiple cycles to deposit a film with a desired thickness. In the cyclic CVD process, precursors and / or reactants can be provided to the reaction chamber with pulses that do not overlap or partially or completely overlap.

[0044] In certain embodiments, at least one of transition metal precursor, nitrogen precursor and auxiliary reaction thing is provided to reaction chamber with pulse.In certain embodiments, transition metal precursor is provided with pulse, nitrogen precursor is provided with pulse, auxiliary reaction thing is provided with pulse, and reaction chamber is purged between continuous pulses of precursor or reactant.Providing transition metal precursor, nitrogen precursor or auxiliary reaction thing in reaction chamber (namely respectively reactant or precursor pulse time) can be for example from about 0.01 second to about 60 seconds, for example from about 0.01 second to about 5 seconds, or from about 1 second to about 20 seconds, or from about 0.5 second to about 10 seconds, or from about 5 seconds to about 15 seconds, or from about 10 seconds to about 30 seconds, or from about 10 seconds to about 60 seconds, or from about 20 seconds to about 60 seconds. The duration of a transition metal precursor or a reactant pulse can be, for example, 0.03 seconds, 0.1 seconds, 0.5 seconds, 1 second, 1.5 seconds, 2 seconds, 2.5 seconds, 3 seconds, 4 seconds, 5 seconds, 8 seconds, 10 seconds, 12 seconds, 15 seconds, 25 seconds, 30 seconds, 40 seconds, 50 seconds, or 60 seconds. In some embodiments, the transition metal precursor pulse time can be at least 5 seconds, or at least 10 seconds, or at least 20 seconds, or at least 30 seconds. In some embodiments, the transition metal precursor pulse time can be at most 5 seconds, or at most 10 seconds, or at most 20 seconds, or at most 30 seconds. In some embodiments, the reactant pulse time can be at least 15 seconds, or at least 30 seconds, or at least 45 seconds, or at least 60 seconds. In some embodiments, the reactant pulse time can be at most 15 seconds, or at most 30 seconds, or at most 45 seconds, or at most 60 seconds.

[0045] The pulse times of the transition metal precursor, nitrogen precursor, and auxiliary reactant vary independently according to the process in question. The selection of a suitable pulse time may depend on the substrate topology. For structures with higher aspect ratios, longer pulse times may be required to obtain sufficient surface saturation in different regions of the high aspect ratio structure. In addition, the selected transition metal precursor and reactant chemicals may affect the suitable pulse time. For the purpose of process optimization, shorter pulse times may be preferred as long as appropriate layer properties can be achieved. In some embodiments, the transition metal precursor pulse time is longer than the nitrogen precursor pulse time. In some embodiments, the nitrogen precursor pulse time is longer than the transition metal precursor pulse time. In some embodiments, the transition metal precursor pulse time is the same as the nitrogen precursor pulse time. In some embodiments, the transition metal precursor pulse time is longer than the auxiliary reactant pulse time. In some embodiments, the nitrogen precursor pulse time is longer than the auxiliary reactant pulse time. In some embodiments, the transition metal precursor pulse time is shorter than the auxiliary reactant pulse time. In some embodiments, the nitrogen precursor pulse time is shorter than the auxiliary reactant pulse time. In some embodiments, the transition metal precursor pulse time is the same as the auxiliary reactant pulse time. In some embodiments, the nitrogen precursor pulse time is the same as the auxiliary reactant pulse time.

[0046] In some embodiments, providing a transition metal precursor, a nitrogen precursor, and / or an auxiliary reactant to a reaction chamber includes pulsing the transition metal precursor, the nitrogen precursor, and / or the auxiliary reactant on a substrate. In certain embodiments, pulse times in the range of several minutes may be used for the transition metal precursor, the nitrogen precursor, and / or the auxiliary reactant. In some embodiments, before the nitrogen precursor is pulsed into the reaction chamber, the transition metal precursor may be pulsed more than once, for example, twice, three times, or four times. Similarly, before the transition metal precursor is pulsed (i.e., provided) into the reaction chamber, the nitrogen precursor or the auxiliary reactant may have more than one pulse, for example, two, three, or four pulses.

[0047] The flow of transition metal precursor, nitrogen precursor and auxiliary reaction thing (being respectively transition metal precursor, nitrogen precursor or auxiliary reaction thing flow) can change to about 20slm from about 5sccm.For every kind of gas, the flow of different reaction gases can be selected independently.In the process that transition metal precursor, nitrogen precursor and / or auxiliary reaction thing are provided in reaction chamber, the flow of transition metal precursor, nitrogen precursor and / or auxiliary reaction thing can be less than 3000sccm or less than 2000sccm or less than 1000sccm or less than 500sccm or less than 100sccm.Transition metal precursor flow, nitrogen precursor flow and / or auxiliary reaction thing flow can be for example 500sccm to 1200sccm, such as 600sccm, 800sccm or 1000sccm. In certain embodiments, the flow rate that transition metal precursor, nitrogen precursor and / or auxiliary reaction thing enter reaction chamber is between 50sccm and 3000sccm, or between 50sccm and 2000sccm, or between 50sccm and 1000sccm.In certain embodiments, the flow rate that transition metal precursor, nitrogen precursor and / or auxiliary reaction thing enter reaction chamber is between 50sccm and 900sccm, or between 50sccm and 800sccm, or between 50sccm and 500sccm.In certain embodiments, higher flow rate can be used.For example, transition metal precursor flow rate, nitrogen precursor flow rate and / or auxiliary reaction thing flow rate can be 5slm or higher.In certain embodiments, transition metal precursor flow rate, nitrogen precursor flow rate and / or auxiliary reaction thing flow rate can be 10slm, 12slm or 15slm or 20slm.

[0048] Purge

[0049] As used herein, the term "purge" may refer to a process of removing gaseous precursors and / or gaseous byproducts from a substrate surface, such as by evacuating a reaction chamber with a vacuum pump and / or by replacing the gas in the reaction chamber with an inert or substantially inert gas such as argon or nitrogen. Purge may be performed between two gas pulses that react with each other. However, purge may be performed between two gas pulses that do not react with each other. For example, purge may be provided between pulses of two precursors or between a precursor and a reactant. Purge may avoid or at least reduce the gas phase interaction between two gases that react with each other. It should be understood that purge may be performed in time or space, or both. For example, in the case of time purge, a purge step may be used, for example, in a time sequence of providing a first precursor to a reaction chamber, providing a purge gas to a reaction chamber, and providing a second precursor to a reaction chamber, wherein the substrate on which the layer is deposited does not move. For example, in the case of space purge, a purge step may take the following form: a substrate is moved from a first position of a continuous supply of a first precursor to a second position of a continuous supply of a second precursor by a purge gas curtain. The purge time can be, for example, from about 0.01 seconds to about 20 seconds, from about 0.05 seconds to about 20 seconds, or from about 1 second to about 20 seconds, or from about 0.5 seconds to about 10 seconds, or between about 1 second to about 7 seconds, such as 5 seconds, 6 seconds, or 8 seconds. However, other purge times can be used if desired, such as where highly conformal step coverage is desired on very high aspect ratio structures or other structures with complex surface morphology, or for specific reactor types such as batch reactors.

[0050] In some embodiments, the method includes removing excess transition metal precursor from the reaction chamber by an inert gas before providing a nitrogen precursor in the reaction chamber. In some embodiments, the reaction chamber is purged between providing a transition metal precursor in the reaction chamber and providing a nitrogen precursor in the reaction chamber. In some embodiments, the reaction chamber is purged between providing a transition metal precursor in the reaction chamber and providing an auxiliary reactant in the reaction chamber. In some embodiments, the reaction chamber is purged between providing a nitrogen precursor in the reaction chamber and providing an auxiliary reactant in the reaction chamber. In some embodiments, the reaction chamber is purged between providing an auxiliary reactant in the reaction chamber and providing a transition metal precursor in the reaction chamber. In some embodiments, the reaction chamber is purged between providing an auxiliary reactant in the reaction chamber and providing a nitrogen precursor in the reaction chamber. In some embodiments, there is a purge step after each precursor and reactant pulse. Therefore, the reaction chamber can also be purged between two pulses of the same chemical substance, such as a transition metal precursor or a nitrogen precursor.

[0051] Thermal Process

[0052] In some embodiments, the cyclic deposition process according to the present disclosure includes a thermal deposition process. In thermal deposition, the temperature increased relative to the ambient temperature promotes the chemical reaction. Generally, in the absence of other external energy sources (such as plasma, free radicals or other forms of radiation), the temperature increase provides the energy required to form the material containing the transition metal nitride. In some embodiments, the method according to the present disclosure is a plasma enhanced deposition method, such as PEALD or PECVD.

[0053] In some embodiments, the material containing the transition metal nitride may be deposited at a temperature of about 20°C to about 800°C. For example, the material containing the transition metal nitride may be deposited at a temperature of about 20°C to about 450°C, or at a temperature of about 50°C to about 450°C, or at a temperature of about 50°C to about 350°C, or at a temperature of about 150°C to about 450°C. In some embodiments of the present invention, the material containing the transition metal nitride may be deposited at a temperature of about 20°C to about 300°C, or at a temperature of about 200°C to about 450°C. In some embodiments, the material containing the transition metal nitride may be deposited at a temperature of about 50°C to about 150°C, or at a temperature of about 250°C to about 400°C, or at a temperature of about 300°C to about 450°C. In some embodiments, the material containing the transition metal nitride may be deposited at a temperature of about 20°C to about 200°C, or at a temperature of about 150°C to about 300°C, or at a temperature of about 150°C to about 450°C.

[0054] For example, the transition metal nitride-containing material may be deposited at a temperature of about 75°C, or about 125°C, or about 175°C, or about 200°C, or about 225°C, or about 325°C, or about 375°C.

[0055] For different process steps, the pressure in the reaction chamber can be selected independently. In some embodiments, a first pressure can be used during a transition metal precursor pulse and a second pressure can be used during a reactant pulse. In a purge or other process step, a third or additional pressure can be used. In some embodiments, during a deposition process according to the present disclosure, the pressure in the reaction chamber is less than 760 Torr, or during a deposition process, the pressure in the reaction chamber is between 0.1 Torr and 760 Torr, or between 1 Torr and 100 Torr, or between 1 Torr and 10 Torr. In some embodiments, during a deposition process, the pressure in the reaction chamber is less than about 0.001 Torr, less than 0.01 Torr, less than 0.1 Torr, less than 1 Torr, less than 10 Torr, less than 50 Torr, less than 100 Torr, or less than 300 Torr. In some embodiments, during at least a portion of a method according to the present disclosure, the pressure in the reaction chamber is less than about 0.001 Torr, less than 0.01 Torr, less than 0.1 Torr, less than 1 Torr, less than 10 Torr, or less than 50 Torr, less than 100 Torr, or less than 300 Torr. For example, in some embodiments, the first pressure can be about 0.1 Torr, about 0.5 Torr, about 1 Torr, about 5 Torr, about 10 Torr, about 20 Torr, or about 50 Torr. In some embodiments, the second pressure is about 0.1 Torr, about 0.5 Torr, about 1 Torr, about 5 Torr, about 10 Torr, about 20 Torr, or about 50 Torr.

[0056] Transition metal precursors

[0057] In the method according to the present invention, the transition metal precursor comprises a transition metal from any one of Groups 4 to 6 of the Periodic Table of Elements.

[0058] The terms "precursor" and "reactant" may refer to molecules (compounds or molecules containing a single element) that participate in a chemical reaction that produces another compound. A precursor typically contains a portion that is at least partially incorporated into the compound or element produced by the chemical reaction. The compound or element thus obtained may be deposited on a substrate. A reactant may be an element or compound that is not incorporated into the resulting compound or element to a significant extent. However, in certain embodiments, a reactant may also contribute to the resulting compound or element.

[0059] As used herein, "transition metal precursor" includes a gas or a material that can be converted to a gaseous state, which can be represented by a chemical formula, including a transition metal selected from Group 4 (titanium, zirconium, hafnium), Group 5 (vanadium, niobium, tantalum) or Group 6 (chromium, molybdenum and tungsten) of the periodic table. In some embodiments, the transition metal is in a low oxidation state relative to the highest stable oxidation state possible for the transition metal. In some embodiments, the oxidation state of the transition metal is 3+. In some embodiments, the oxidation state of the transition metal is 2+. In some embodiments, the oxidation state of the transition metal is zero.

[0060] In some embodiments, the transition metal precursor comprises a Group 4 transition metal. The transition metal precursor may therefore comprise titanium (Ti). Alternatively, the transition metal precursor may comprise zirconium (Zr). As another alternative, the transition metal precursor may comprise hafnium (Hf). In some embodiments, the transition metal in the transition metal precursor is selected from titanium, zirconium and hafnium. In some embodiments, the transition metal in the transition metal precursor is selected from titanium and hafnium.

[0061] In some embodiments, the transition metal precursor comprises a Group 5 transition metal. Thus, the transition metal precursor may comprise vanadium (V), or the transition metal precursor may comprise niobium (Nb), or the transition metal precursor may comprise tantalum (Ta). In some embodiments, the transition metal in the transition metal precursor is selected from vanadium, niobium, and tantalum. In some embodiments, the transition metal in the transition metal precursor is selected from vanadium and tantalum.

[0062] In some embodiments, the transition metal precursor includes a Group 6 transition metal. The transition metal precursor may include chromium (Cr). The transition metal precursor may include molybdenum (Mo). In some embodiments, the Group 6 transition metal in the transition metal precursor is molybdenum. The transition metal precursor may include tungsten (W). In some embodiments, the transition metal in the transition metal precursor is selected from chromium, molybdenum and tungsten. In some embodiments, the transition metal in the transition metal precursor is selected from molybdenum and tungsten.

[0063] In some embodiments, the transition metal precursor is provided as a mixture of two or more compounds. In the mixture, other compounds except the transition metal precursor can be inert compounds or elements. In some embodiments, the transition metal precursor is provided in a composition. Components suitable for use as a composition can include a transition metal compound and an effective amount of one or more stabilizers. The composition can be a solution or a gas under standard conditions.

[0064] In an embodiment of the present disclosure, the transition metal precursor includes a transition metal atom and an organic ligand. In certain embodiments, the transition metal precursor includes a metal organic precursor, which includes a transition metal according to the present disclosure. Therefore, the transition metal precursor is a metal organic precursor. Metal-organic precursor refers to a transition metal precursor comprising a metal (such as a transition metal of Group 4-6 according to the present disclosure) and an organic ligand in this article, wherein the metal atom is not directly bonded to a carbon atom. In certain embodiments, the metal organic precursor includes a transition metal atom, which is not directly combined with a carbon atom. In certain embodiments, the metal organic precursor includes two or more transition metal atoms, none of which is directly bonded to a carbon atom. In certain embodiments, the metal organic precursor includes two or more transition metal atoms, wherein at least one transition metal atom is not directly bonded to a carbon atom.

[0065] In some embodiments, the transition metal precursor comprises an organometallic compound, which comprises a transition metal according to the present disclosure. Therefore, the transition metal precursor is an organometallic precursor. An organometallic precursor refers herein to a transition metal precursor comprising a transition metal (e.g., a Group 4-6 transition metal according to the present disclosure) and an organic ligand, wherein the transition metal atom is directly bonded to a carbon atom. In embodiments where the organometallic precursor comprises two or more transition metal atoms, all metal atoms are directly bonded to carbon atoms.

[0066] In some embodiments, the transition metal precursor comprises only transition metal atoms, carbon and hydrogen according to the present disclosure. In other words, the transition metal precursor does not contain oxygen, nitrogen or other additional elements. In some embodiments, the transition metal precursor comprises only molybdenum, carbon and hydrogen. In some embodiments, the transition metal precursor comprises only tungsten, carbon and hydrogen. In some embodiments, the transition metal precursor comprises only niobium, carbon and hydrogen. In some embodiments, the transition metal precursor comprises only zirconium, carbon and hydrogen.

[0067] However, in some embodiments, the metal organic or organometallic precursor comprises a transition metal according to the present disclosure, carbon, hydrogen and at least one additional element. The additional element may be, for example, oxygen, nitrogen or a halogen. In some embodiments, the additional element is not directly bonded to the metal. Therefore, in some embodiments, the transition metal precursor does not contain a metal-nitrogen bond. In some embodiments, the transition metal precursor does not contain a metal-oxygen bond. In some embodiments, the transition metal precursor does not contain a metal-halogen bond. At least one additional element in the metal organic or organometallic precursor may be a ligand. Therefore, at least one additional element may be an additional ligand. In some embodiments, the metal organic or organometallic precursor comprises an additional ligand, and the ligand is a halide. In some embodiments, the metal organic or organometallic precursor may include at least two additional ligands, and one or two additional ligands may be a halide. Each additional ligand may be independently selected. The halide may be selected from chlorine, bromine and iodine. Therefore, the ligand may be a halogen atom selected from chlorine, bromine and iodine.

[0068] In some embodiments, the transition metal precursor comprises an olefin ligand. In some embodiments, the transition metal precursor comprises a π-arene ligand. In some embodiments, the transition metal precursor comprises a carbonyl ligand. In some embodiments, the transition metal precursor comprises an additional ligand.

[0069] In some embodiments, the transition metal precursor comprises at least two organic ligands. In some embodiments, the transition metal precursor comprises at least three organic ligands. In some embodiments, the transition metal precursor comprises four organic ligands. In some embodiments, the transition metal precursor comprises an organic ligand and a hydride ligand. In some embodiments, the transition metal precursor comprises an organic ligand and two or more hydride ligands. In some embodiments, the transition metal precursor comprises two organic ligands and two hydride ligands. In some embodiments, one or more organic ligands are hydrocarbon ligands.

[0070] In some embodiments, the transition metal precursor includes a cyclic moiety. For example, the transition metal precursor may include a benzene or cyclopentadienyl ring. In some embodiments, the transition metal precursor includes a benzene or cyclopentadienyl ring. The transition metal precursor may include one or more benzene rings. In some embodiments, the transition metal precursor includes two benzene rings. One or two benzene rings may include a hydrocarbon substituent. In some embodiments, each benzene ring of the transition metal precursor includes an alkyl substituent. The alkyl substituent may be a methyl, ethyl, or a straight or branched alkyl group containing three, four, five, or six carbon atoms. For example, the alkyl substituent of the benzene ring may be a n-propyl or isopropyl group. In addition, the alkyl substituent may be a n-, iso-, tert-, or sec-form of a butyl, pentyl, or hexyl moiety. In some embodiments, the transition metal precursor includes, is substantially composed of, or is composed of a bis(ethylbenzene) transition metal. In some embodiments, the transition metal precursor comprises, consists essentially of, or consists of V(Bz)2, MoBz2, CrBz2, WBz2, V(EtBz)2, Mo(EtBz)2, Cr(EtBz)2, or W(EtBz)2, wherein Bz represents benzene and Et represents ethyl. In some embodiments, the transition metal precursor comprises bis(ethylbenzene) molybdenum. In some embodiments, the transition metal precursor consists essentially of bis(ethylbenzene) molybdenum, or consists of bis(ethylbenzene) molybdenum.

[0071] The transition metal precursor may include one or more cyclopentadienyl groups. In certain embodiments, the transition metal precursor includes two cyclopentadienyl groups. The cyclopentadienyl group may be similarly substituted with phenyl. In other words, one or more cyclopentadienyl groups may include hydrocarbon substituents. In certain embodiments, one or two cyclopentadienyl groups may include alkyl substituents, such as methyl, ethyl, or a straight or branched alkyl group containing three, four, five, or six carbon atoms. For example, the alkyl substituent of the cyclopentadienyl group may be n-propyl, isopropyl. In addition, the alkyl substituent may be the normal-, iso-, tertiary-, or secondary-form of a butyl, pentyl, or hexyl moiety.

[0072] Some examples of transition metal precursors containing cyclopentadienyl moieties according to the present invention are TiCp2Cl2, TiCp2Br2, TiCp2, TiCp2(CO)2, TiCp2I2, TiCp2H2, TiCpCl3, TiCpBr3, TiCpI3, HfCp2Cl2, HfCp2Br2, HfCp2, HfCp2(CO)2, HfCp2I2, HfCp2H2, HfCpCl3, HfCpBr3, HfCpI3, ZrCp2Cl2, ZrCp2Br2, ZrCp2, ZrCp2(C O)2,ZrCp2I2,ZrCp2H2,ZrCpCl3,ZrCpBr3,ZrCpI3,VCp2Cl2,VCp2Br2,VCp2I2,VCp2,VCp2(CO)4,TaCp2Cl2,TaCp2I2,TaCp2B r2, TaCp2H2, NbCp2, NbCp2H2, NbCp2Cl2, MoCp2Cl2, MoCp2H2, CrCp2H2, CrCp2, CrCp2Cl2, WCp2H2, WCp2Cl2, WCp2Br2 and WCp2I2.

[0073] Some additional examples of transition metal precursors containing cyclopentadienyl groups are. In Ti(iPrCp)2Cl2, Ti(iPrCp)2, Ti(MeCp)2Cl2, Ti(MeCp)2, Ti(EtCp)2Cl2, Ti(EtCp)2, Hf(iPrCp)2Cl2, Hf(iPrCp)2, Hf(MeCp)2Cl2, Hf(MeCp)2, Hf(EtCp)2Cl2, Hf(EtCp)2, Zr(iPrCp)2Cl2, Zr(iPrCp)2, Zr(MeCp)2Cl2, Zr(MeCp)2, Zr(EtCp)2Cl2, Zr(EtCp)2, V(iPrCp)2Cl2, V(iPrCp)2, V(MeCp)2Cl2, V(MeCp)2, V(EtCp)2Cl2, V(EtCp)2, Mo(iPrCp)2Cl2, Mo(iPrCp)2H2, Mo(EtCp)2H2, Cr(MeCp)2, Cr(EtCp)2, Cr(iPrCp)2, Cr(tBuCp)2, Cr(nBuCp)2, Cr(Me5Cp)2, Cr(Me4Cp)2, W(EtCp)2H2, W(iPrCp)2Cl2 and W(iPrCp)2H2. In the formula, Cp represents cyclopentadienyl, iPr represents isopropyl, Me represents methyl, Et represents ethyl, iPr represents isopropyl, tBu represents tert-butyl, and nBu represents n-butyl.

[0074] In some embodiments, the transition metal precursor may include a carbonyl-containing ligand. For example, the transition metal precursor may include, consist essentially of, or consist of Mo(CO)6, Mo(1,3,5-cycloheptatriene)(CO)3. In addition, in some embodiments, the transition metal precursor includes a nitrosyl-containing ligand. For example, the molybdenum precursor may include, consist essentially of, or consist of MoCp(CO)2(NO).

[0075] nitrogen precursor

[0076] The term nitrogen precursor may refer to a gas or material that can be changed into a gaseous state and may be represented by a chemical formula including nitrogen. In some cases, the chemical formula includes nitrogen and hydrogen. In some cases, the nitrogen precursor does not include diatomic nitrogen.

[0077] The nitrogen precursor may be selected from one or more of molecular nitrogen (N2), ammonia (NH3), hydrazine (NH2NH2), hydrazine derivatives, nitrogen-based plasmas, and other compounds containing nitrogen and hydrogen or consisting of nitrogen and hydrogen. In some embodiments, the nitrogen precursor comprises hydrazine. In some embodiments, the nitrogen precursor consists essentially of or consists of hydrazine. In some embodiments, the nitrogen precursor comprises hydrazine substituted with one or more alkyl or aryl substituents. In some embodiments, the nitrogen precursor consists essentially of or consists of hydrazine substituted with one or more alkyl or aryl substituents. In some embodiments, the hydrazine derivative comprises an alkyl hydrazine, which comprises at least one of the following: tert-butyl hydrazine (C4H9N2H3), methyl hydrazine (CH3NHNH2), 1,1-dimethyl hydrazine ((CH3)2NNH2), 1,2-dimethyl hydrazine (CH3)NHNH(CH3), ethyl hydrazine, 1,1-diethyl hydrazine, 1-ethyl-1-methyl hydrazine, isopropyl hydrazine, tert-butyl hydrazine, phenyl hydrazine, 1,1-diphenyl hydrazine, 1,2-diphenyl hydrazine, N -aminopiperidine, N-aminopyrrole, N-aminopyrrolidine, N-methyl-N-phenylhydrazine, 1-amino-1,2,3,4-tetrahydroquinoline, N-aminopiperazine, 1,1-dibenzylhydrazine, 1,2-dibenzylhydrazine, 1-ethyl-1-phenylhydrazine, 1-aminoazetidine, 1-methyl-1-(m-tolyl)hydrazine, 1-ethyl-1-(p-tolyl)hydrazine, 1-aminoimidazole, 1-amino-2,6-dimethylpiperidine, N-aminoaziridine or tert-azobutane.

[0078] In some embodiments, the nitrogen precursor includes a plasma, such as NH3 plasma, N2 plasma, and / or N2 / H2 plasma. In some embodiments, the nitrogen-based plasma can be generated by applying RF power to a nitrogen-containing gas, and the nitrogen-based plasma can include atomic nitrogen (N), nitrogen ions, nitrogen radicals, and excited species of nitrogen. In some embodiments, the nitrogen-based plasma can further include additional reactive species, such as by adding additional gases.

[0079] In some embodiments, the nitrogen precursor includes only nitrogen and hydrogen. For example, a mixture of nitrogen and hydrogen can be used. In some embodiments, the nitrogen precursor is a mixture of gaseous H2 and N2. In some embodiments, the nitrogen precursor is selected from NH3, NH2NH2 and a mixture of gaseous H2 and N2. In some embodiments, the nitrogen precursor does not include diatomic nitrogen, that is, the nitrogen precursor is a non-diatomic precursor. In some embodiments, the nitrogen precursor includes ammonia. In some embodiments, the nitrogen precursor is essentially composed of or consists of ammonia. In some embodiments, the nitrogen precursor includes an alkylamine. In some embodiments, the nitrogen precursor is essentially composed of or consists of an alkylamine. Examples of alkylamines include dimethylamine, n-butylamine and tert-butylamine.

[0080] Auxiliary reactants

[0081] In some embodiments, the method according to the present disclosure also includes providing an auxiliary reactant to the reaction chamber in the gas phase. The auxiliary reactant can change the carbon content of the material containing transition metal nitride. For example, the carbon content of the deposited material can be adjusted by modifying the ratio of the nitrogen precursor provided to the reaction chamber and the auxiliary reactant provided to the reaction chamber. This can in turn be used to adjust the work function of the transition metal nitride layer. In some embodiments, reducing the amount of the auxiliary reactant provided to the reaction chamber relative to the amount of the nitrogen precursor provided to the reaction chamber will reduce the work function of the deposited layer. In some embodiments, providing an auxiliary reactant in the reaction chamber can reduce the resistivity of the material containing transition metal nitride deposited. In some embodiments, increasing the amount of the auxiliary reactant provided to the reaction chamber relative to the nitrogen precursor can reduce the resistivity of the material containing transition metal nitride deposited.

[0082] Si,Ge,Sn

[0083] In some embodiments of the method according to the present disclosure, the auxiliary reactant includes a Group 14 element selected from silicon (Si), germanium (Ge) or tin (Sn). In some embodiments, the auxiliary reactant includes a Group 14 element selected from Si and Ge. In some embodiments, the auxiliary reactant includes a Group 14 element selected from Si and Sn. In some embodiments, the auxiliary reactant includes a Group 14 element selected from Ge and Sn.

[0084] In some embodiments, according to the present disclosure, the auxiliary reaction comprises an atom of the 14th group element. In some embodiments, according to the present disclosure, the auxiliary reaction comprises two atoms of the 14th group element. Two or more atoms of the 14th group element can be the same or different elements. For example, the auxiliary reaction can include two Si atoms, two Ge atoms or two Sn atoms. Alternatively, the auxiliary reaction can include Si atoms and Ge atoms, Si atoms and Sn atoms or Sn atoms and Ge atoms. In some embodiments, the auxiliary reaction comprises two atoms of the 14th group element bonded to each other according to the present disclosure.

[0085] In certain embodiments, the auxiliary reaction comprises two atoms of the 14th group element according to the present disclosure bonded to each other, and each atom of the 14th group element has a halogen atom connected thereto. Halogen can be, for example, Cl, F or I. In certain embodiments, the auxiliary reaction comprises two atoms of the 14th group element according to the present disclosure bonded to each other, and each atom of the 14th group element has an alkyl group connected thereto. For example, the alkyl group can be methyl, ethyl, propyl, butyl or amyl.

[0086] In some embodiments, the auxiliary reaction comprises at least one Si-Si bond. In some embodiments, the auxiliary reaction comprises at least one Ge-Ge bond. In some embodiments, the auxiliary reaction comprises at least one Sn-Sn bond. In some embodiments, the auxiliary reaction comprises at least one Si-Si bond, and the halogen atom is connected to each Si atom. In some embodiments, the auxiliary reaction comprises at least one Ge-Ge bond, and the halogen atom is connected to each Ge atom. In some embodiments, the auxiliary reaction comprises at least one Sn-Sn bond, and the halogen atom is connected to each Ge atom. In some embodiments, the auxiliary reaction comprises a bond between the 14th group elements, and the halogen atom is connected to each 14th group element atom.

[0087] In certain embodiments, in addition to the 14th group element, the auxiliary reaction also includes an organic group. The organic group is a group containing a carbon-hydrogen bond. Therefore, the auxiliary reaction includes the 14th group element and the organic group selected from Si, Ge and Sn. The auxiliary reaction may include a hydrocarbon containing at least one carbon atom. There may be one, two, three or four organic groups in the auxiliary reaction. Each organic group may independently contain 1 to 12 carbon atoms. For example, each organic group may independently include a C1 to C4 group (i.e., containing 1 to 4 carbon atoms), a C1 to C6 group, a C1 to C8 group, a C1 to C10 group, a C2 to C12 group, a C2 to C6 group, a C2 to C6 group, or a C4 to C8 group or a C4 to C10 group. Therefore, each organic group may independently include a C1, C2, C3, C4, C5, C6, C7, C8 or C10 group. The organic group may include an alkyl or aryl group. The organic group may include one or more straight chain, branched or cyclic alkyl groups. In some embodiments, the organic group includes an aryl group. The alkyl or aryl group may be substituted with one or more functional groups, such as halogen, alcohol, amine, or benzene.

[0088] For example, the organic group can include methyl halide, ethane, propane, 2-methylpropane, 2,2-dimethylpropane (neopentane), n-butane, 2-methylbutane, 2,2-dimethylbutane, n-pentane, 2-methylpentane, 3-methylpentane or n-hexane. In certain embodiments, the auxiliary reaction includes two halogen atoms. In some other embodiments, at least two halogen atoms of the auxiliary reaction can be connected to different carbon atoms. The halogen atom can be the same halogen, such as bromine, iodine, fluorine or chlorine. Alternatively, halogen can be different halogens, such as iodine and bromine, bromine and chlorine, chlorine and iodine. In certain embodiments, the auxiliary reaction includes 1,2-dihaloalkane or 1,2-dihaloalkene or 1,2-dihaloalkyne or 1,2-dihaloaromatic hydrocarbons, wherein the halogen is connected to adjacent carbon atoms.

[0089] In some embodiments, the auxiliary reactant has the general formula (I): R a MX b or R c X d M-MR c X d . In formula (I), a is 0, 1, 2 or 3, b is 4-a, c is 0, 1 or 2, d is 3-c, R is an organic group as described above, M is Si, Ge or Sn, and each X is independently any ligand. R can be a hydrocarbon. If a is two or three, or c is two, each R is independently selected. In some embodiments, each R is selected from alkyl and aryl. In some embodiments, R is an organic group as described above. In some embodiments, R is an alkyl or aryl. For clarity, X can represent different ligands in an auxiliary reaction material. Therefore, in some embodiments, the auxiliary reaction material can be, for example, SiH2Br2, SiH2I2 or SiH2Cl2.

[0090] In some embodiments, X is hydrogen, substituted or unsubstituted alkyl or aryl, or halogen. In some embodiments, X is H. In some embodiments, X is alkyl or aryl. In some embodiments, X is C1 to C4 alkyl. In some embodiments, X is substituted alkyl or aryl. In some embodiments, X is substituted alkyl or aryl, wherein the substituent is the same as M. In some embodiments, X is selected from H, Me, Et, nPr, iPr, nBu, tBu, M'Me3, M'Et3, M'Pr3, M'Bu3, Cl, Br or I, wherein M' is the same as M.

[0091] In some embodiments, the auxiliary reactant has a more specific formula (II) R a SiX b. More specifically, the auxiliary reactant can have the formula R3SiX, R2SiX2, RSiX3 or SiX4. In formula (II), a, b, R and X are the same as in formula (I). However, in some embodiments, the silicon atom does not contain four identical substituents. In some embodiments, the auxiliary reactant is not SiH4. In some embodiments, the auxiliary reactant is not SiH2Me2. In some embodiments, the auxiliary reactant is not SiH2Et2. In some embodiments, the auxiliary reactant is not Si2H2.

[0092] In some embodiments, the auxiliary reactant has a more specific formula (III) R a GeX b . More specifically, the auxiliary reactant can have the formula R3GeX, R2GeX2, RGeX3 or GeX. In formula (III), a, b, R and X are the same as in formula (I). However, in some embodiments, the Ge atom does not contain four identical substituents. In some embodiments, the auxiliary reactant is not GeH4.

[0093] In some embodiments, the auxiliary reactant has a more specific formula (IV) R a S X b . More specifically, the auxiliary reactant can have the formula R3SnX, R2SnX2, RSnX3 or SnX4. In formula (IV), a, b, R and X are the same as in formula (I). However, in some embodiments, the tin atom does not contain four identical substituents. In some embodiments, the auxiliary reactant is not SnH4.

[0094] In some embodiments, the auxiliary reactant includes a halogen selected from iodine and bromine. In some embodiments, the auxiliary reactant includes an alkyl halide. In some embodiments, the auxiliary reactant includes an alkyl bromide. In some embodiments, the auxiliary reactant includes an alkyl iodide. In some embodiments, the auxiliary reactant includes an aryl halide. In some embodiments, the auxiliary reactant includes an aryl bromide. In some embodiments, the auxiliary reactant includes an aryl iodide. In some embodiments, the auxiliary reactant includes an acyl halide. In some embodiments, the auxiliary reactant includes an acyl bromide. In some embodiments, the auxiliary reactant includes an acyl iodide. In some embodiments, the auxiliary reactant includes, is essentially composed of, or is composed of a molecular halogen. In some embodiments, the auxiliary reactant includes molecular iodine I2. In some embodiments, the auxiliary reactant includes molecular bromine Br2. In some embodiments, the auxiliary reactant includes a compound containing a silicon-halogen bond. In some embodiments, the auxiliary reactant includes a compound containing a silicon-bromine bond. In some embodiments, the auxiliary reactant includes a compound containing a silicon-iodine bond.

[0095] In certain embodiments, the auxiliary reaction material comprises a halogenated organic compound (organic halide), and the halogen is selected from bromine and iodine. In certain embodiments, the organic halide comprising bromine and / or iodine does not comprise a Group 14 element. Some auxiliary reaction materials may comprise one or more Group 14 elements and an organic halide group selected from Si, Ge and Sn, wherein the halogen is selected from bromine and iodine.

[0096] In certain embodiments, the organic halide in the auxiliary reaction material comprises two or more halogen atoms. The auxiliary reaction material may or may not comprise a Group 14 element. Therefore, in certain embodiments, the auxiliary reaction material is composed of carbon, hydrogen and one or more halogen atoms selected from I and Br. In certain embodiments, the auxiliary reaction material is composed of carbon, oxygen, hydrogen and one or more halogen atoms selected from I and Br.

[0097] In some embodiments, the auxiliary reactant includes a hydrocarbon containing a bromine atom or an iodine atom. In some embodiments, the auxiliary reactant includes a hydrocarbon containing at least one halogen atom, each halogen being independently selected from bromine and iodine. In some embodiments, the auxiliary reactant includes a hydrocarbon containing two or more bromine or iodine atoms. In some embodiments, the auxiliary reactant includes a hydrocarbon, wherein two or more bromine or iodine atoms are bonded to a single carbon atom. In some embodiments, the auxiliary reactant includes a hydrocarbon containing two or more halogen atoms, the halogen atoms being selected from bromine and iodine. In some embodiments, the auxiliary reactant includes a hydrocarbon, wherein two or more bromine or iodine atoms are bonded to a single carbon atom. In some embodiments, the auxiliary reactant includes a hydrocarbon, wherein two or more bromine or iodine atoms are bonded to different carbon atoms. In some embodiments, at least two halogen atoms in the auxiliary reactant are connected to adjacent carbon atoms of the hydrocarbon. In some embodiments, the carbon atoms are not adjacent, i.e., the carbon atoms are not directly bonded to each other. In some embodiments, the auxiliary reactant includes 1,2-dihaloalkane or 1,2-dihaloalkene or 1,2-dihaloalkyne or 1,2-dihaloarene. In some embodiments, the halogen atoms of the auxiliary reactant are the same halogen. In some embodiments, the two halogen atoms of the auxiliary reactant are iodine. In some embodiments, the two halogen atoms of the auxiliary reactant are bromine. In some embodiments, the auxiliary reactant includes 1,2-diiodoethane. In some embodiments, the auxiliary reactant is substantially composed of or consists of 1,2-diiodoethane.

[0098] In some embodiments, the auxiliary reactant has the general formula (V): a R b C—(CX c R” d ) n —CX a R' b, wherein X is halogen, R, R' and R" are independently H or alkyl, a and b are independently 1 or 2, so that for each carbon atom a+b=3, n is 0, 1, 2, 3, 4 or 5, and c and d are independently 0, 1 or 2, so that for each carbon atom c+d=2.

[0099] In some embodiments, the auxiliary reactant has the general formula (VI): a R b C—CX a R' b , wherein X is halogen, R and R' are independently H or alkyl, and a and b are independently 1 or 2, so that a+b=3 for each carbon atom.

[0100] In some embodiments, the method includes providing a WF modified reactant into the reaction chamber. The WF modified reactant can be used to modify the work function of the material containing transition metal nitride. In some embodiments, the WF modified reactant includes a thiol. In some embodiments, the WF modified reactant includes a C2 to C10 thiol. In some embodiments, the WF modified reactant includes a C2 to C10 dithiol. In some embodiments, the WF modified reactant includes a C3 to C10 thiol. In some embodiments, the WF modified reactant includes a C3 to C10 dithiol. In some embodiments, the WF modified reactant includes a C4 to C10 thiol. In some embodiments, the WF modified reactant includes a C4 to C10 dithiol. Therefore, in some embodiments, the WF modified reactant includes a volatile organic compound containing at least one thiol group. Therefore, in some embodiments, the WF modified reactant includes a volatile organic compound containing at least two thiol groups. In some embodiments, the WF modified reactant includes two thiol groups connected to adjacent carbon atoms. In some embodiments, the WF modified reactant includes a sulfhydryl group at the end of the carbon chain. In certain embodiments, the WF modified reactant only comprises a sulfhydryl group at the end of the carbon chain. In certain embodiments, the WF modified reactant comprises two thiol groups at the end of the carbon chain. The two sulfhydryl groups at the end of the carbon chain can be connected to a single carbon atom, or to the last two carbon atoms at the end of the carbon chain. In certain embodiments, the WF modified reactant comprises at least one thiol group and an alkyl group. In certain embodiments, the WF modified reactant is composed of at least one thiol group and an alkyl group. The alkyl group of the thiol compound can be straight chain, branched or cyclic. The example of the thiol compound includes ethane-1-thiol, propane-1-thiol, butane-1-thiol, pentane-1-thiol, hexane-1-thiol, heptane-1-thiol and octane-1-thiol. Other examples of thiol compounds include ethane-1,2-dithiol, propane-1,2-dithiol, butane-1,2-dithiol, pentane-1,2-dithiol, hexane-1,2-dithiol, heptane-1,2-dithiol and octane-1,2-dithiol. In some embodiments, the thiol compound consisting of one or more thiol groups and an alkyl group can reduce the work function of the deposited transition metal nitride layer. The carbon chain can branch at different positions. For example, in some embodiments, the thiol compound may include, for example, 2-methylpropane-1-thiol, 2-methylbutane-1-thiol, 2,2-propane-1-thiol, 2-methylpentane-1-thiol, 5-methylpentane-1-thiol, 2,4-dimethylpentane-1-thiol or 2-methylheptane-1-thiol.In further embodiments, the thiol compound may include, for example, 2-methylpropane-1,2-dithiol, 2-methylbutane-1,2-dithiol, 2,2-propane-1,2-dithiol, 2-methylpentane-1,2-dithiol, 5-methylpentane-1,2-dithiol, 2,4-dimethylpentane-1,2-dithiol or 2-methylheptane-1,2-dithiol. In some embodiments, the thiol compound may include nonane or decane containing 1 or 2 thiol groups.

[0101] In some embodiments, the thiol compound includes a halogen, such as fluorine. In some embodiments, a thiol compound comprising a halogen (e.g., fluorine), one or more thiol groups, and an alkyl group can increase the work function of the deposited transition metal nitride layer. In some embodiments, the thiol compound is a fluoroalkylthiol. In some embodiments, the fluoroalkylthiol comprises a C3 to C12 such as a C8 to C10 alkyl chain. In some embodiments, the fluoroalkylthiol comprises a C3 to C12 such as a C8 to C10 straight alkyl chain. In some embodiments, the thiol compound comprises at least two, or at least three, or at least six, or at least eight, or at least ten, or at least twelve fluorine atoms. In some embodiments, the thiol compound comprises six fluorine atoms. In some embodiments, the thiol compound comprises eight fluorine atoms. In some embodiments, the thiol compound comprises ten fluorine atoms. In some embodiments, the thiol compound comprises twelve fluorine atoms. In some embodiments, the thiol compound is 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanethiol. In some embodiments, the thiol compound is 3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluoro-1-decanethiol.

[0102] In some embodiments, during the deposition of the transition metal nitride-containing material, the WF-modified reactant is provided to the reaction chamber at least in a deposition cycle. In some embodiments, the WF-modified reactant is provided to the reaction chamber after the last deposition cycle of the deposition process. In some embodiments, the WF-modified reactant is provided to the reaction chamber after the deposition is completed. Thus, providing the WF-modified reactant can be used as a post-treatment to change the work function of the deposited layer.

[0103] In another aspect, a transition metal nitride layer produced by a cyclic deposition process is disclosed. The method includes providing a substrate in a reaction chamber, providing a transition metal precursor to the reaction chamber in a gas phase; and providing an auxiliary reactant to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. The transition metal precursor in the method includes a transition metal from any one of Groups 4 to 6 of the periodic table.

[0104] In some embodiments, a transition metal nitride layer according to the present disclosure has a resistivity of less than about 600 μΩ·cm.

[0105] In some embodiments, the transition metal nitride layer according to the present disclosure has a carbon content of less than about 20 atomic %. For example, the carbon content of the transition metal layer deposited according to the present invention can be less than 15 atomic % or less than 10 atomic % or less than 3 atomic %.

[0106] In one aspect, a semiconductor structure comprising a transition metal nitride deposited by a cyclic deposition process is disclosed. The method comprises providing a substrate in a reaction chamber, providing a transition metal precursor to the reaction chamber in a gas phase, and providing a nitrogen precursor to the reaction chamber in a gas phase to form a transition metal nitride on the substrate. In the method, the transition metal precursor comprises a transition metal from any one of Groups 4 to 6 of the periodic table. Thus, a semiconductor structure comprising a transition metal nitride deposited according to the method of the present disclosure is disclosed.

[0107] In another aspect, a semiconductor device comprising a transition metal nitride deposited by a cyclic deposition process is disclosed. The method comprises providing a substrate in a reaction chamber, providing a transition metal precursor in a gas phase to the reaction chamber, and providing a nitrogen precursor in a gas phase to the reaction chamber to form a transition metal nitride on the substrate. In the method, the transition metal precursor comprises a transition metal from any one of Groups 4 to 6 of the periodic table. Thus, a semiconductor device comprising a transition metal nitride deposited according to the method of the present disclosure is disclosed.

[0108] In another aspect, a deposition assembly for depositing a material containing a transition metal nitride on a substrate is disclosed. The deposition assembly includes one or more reaction chambers and a precursor injector system, the reaction chamber is constructed and arranged to hold a substrate, and the precursor injector system is constructed and arranged to provide a transition metal precursor, an auxiliary reactant, and a nitrogen precursor to the reaction chamber in a gas phase. The deposition assembly also includes a precursor container, the precursor container is constructed and arranged to accommodate a transition metal precursor, the transition metal precursor includes a transition metal from any one of Groups 4 to 6 of the periodic table, and the assembly is constructed and arranged to provide the transition metal precursor, the auxiliary reactant, and the nitrogen precursor to the reaction chamber through the precursor injector system to deposit the material containing the transition metal nitride on the substrate.

[0109] The present disclosure is further explained by the following exemplary embodiments depicted in the accompanying drawings. The illustrations presented herein are not meant to be actual views of any particular material, structure, device, or apparatus, but are merely schematic representations of embodiments of the present disclosure. It should be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the sizes of some elements in the drawings may be exaggerated relative to other elements to help improve the understanding of the illustrated embodiments of the present disclosure. The structures and devices depicted in the drawings may include additional elements and details, which may be omitted for clarity.

[0110] Figure 1A 1 is a block diagram of an exemplary embodiment of a method 100 for depositing a transition metal nitride-containing material on a substrate. The method 100 may be used to form a layer containing a transition metal nitride, i.e., a transition metal nitride layer. The transition metal nitride layer may be used in the formation of a structure or device, such as the structure or device described herein. However, unless otherwise stated, the methods described herein are not limited to these applications.

[0111] In the first stage 102, a substrate is provided into a reaction chamber. The substrate according to the present disclosure may include, for example, an oxide, such as silicon oxide (e.g., thermal silicon oxide or natural silicon oxide), aluminum oxide, or a transition metal oxide, such as hafnium oxide. The substrate may include a nitride such as silicon nitride or titanium nitride, a metal such as copper, cobalt, or tungsten, a chalcogenide material such as molybdenum sulfide. A transition metal nitride according to the present invention may be deposited on the surface.

[0112] The reaction chamber may form part of an atomic layer deposition (ALD) assembly. The assembly may be a single wafer reactor. Alternatively, the reactor may be a batch reactor. The various stages of method 100 may be performed in a single reaction chamber, or may be performed in multiple reaction chambers, such as reaction chambers of a combination tool. In some embodiments, method 100 is performed in a single reaction chamber of a combination tool, but other, previous or subsequent manufacturing steps of the structure or device are performed in additional reaction chambers of the same combination tool. Optionally, the assembly including the reaction chamber may be provided with a heater to activate the reaction by raising the temperature of one or more substrates and / or reactants and / or precursors. The material containing transition metal nitrides according to the present disclosure may be deposited in a cross-flow reaction chamber. The material containing transition metal nitrides according to the present disclosure may be deposited in a cross-flow reaction chamber.

[0113] During step 102, the substrate may be brought to the temperature and pressure required to perform the method according to the present disclosure, i.e., the precursor and / or reactant is provided to the reaction chamber. The temperature in the reaction chamber (e.g., the temperature of the substrate or substrate support) may be, for example, from about 50°C to about 350°C, from about 150°C to about 400°C, from about 200°C to about 350°C, or from about 200°C to about 450°C. In an exemplary embodiment, a temperature of up to 400°C may be used to deposit molybdenum nitride. The deposition temperature may be limited by the decomposition of the precursor used in the process, and may therefore be, for example, 280°C, 320°C, 350°C, or 370°C. In some cases, it may be advantageous to use different temperatures for different precursors. In some embodiments, the reaction chamber includes a top plate, and the top plate temperature may be lower than the substrate pedestal temperature. For example, the top plate temperature may be at least 50°C lower than the pedestal temperature. For example, the top plate temperature may be 50°C, 60°C, 70°C, or 80°C lower than the pedestal temperature. In some embodiments, the susceptor temperature may be at least 300°C, such as about 350°C or about 370°C.

[0114] The pressure in the reaction chamber can be less than 760 Torr, or less than 350 Torr, or less than 100 Torr, or less than 50 Torr, or less than 10 Torr. For example, the pressure in the reaction chamber can be about 400 Torr, about 100 Torr, about 50 Torr, about 20 Torr, about 5 Torr, or about 0.1 Torr. Different pressures can be used for different process steps.

[0115] A transition metal precursor is provided in a reaction chamber comprising substrate 104. Without limiting the present disclosure to any particular theory, in the process of providing the transition metal precursor in the reaction chamber, the transition metal precursor can be chemically adsorbed on the substrate. The duration (transition metal precursor pulse time) of providing the transition metal precursor in the reaction chamber can be, for example, 0.01 seconds, 0.5 seconds, 1 second, 1.5 seconds, 2 seconds, 4 seconds, 10 seconds, 20 seconds, 35 seconds, 50 seconds or 60 seconds. In some embodiments, the duration (transition metal precursor pulse time) of providing the transition metal precursor in the reaction chamber can be longer than 5 seconds or longer than 10 seconds or longer than 30 seconds. Alternatively, the transition metal purge time can be shorter than 60 seconds, shorter than 30 seconds, shorter than 10 seconds, shorter than 4 seconds, shorter than 1 second or shorter than 0.5 seconds. For example, for an organometallic transition metal precursor comprising an aromatic group, a pulse time of about 10 to 20 seconds may be suitable.

[0116] When the nitrogen precursor is provided in the reaction chamber 106, it can react with the chemically adsorbed transition metal precursor or its derivative species to form a transition metal nitride on the substrate. The duration of providing the nitrogen precursor in the reaction chamber (nitrogen precursor pulse time) can be, for example, 0.1 seconds, 0.5 seconds, 1 second, 3 seconds, 4 seconds, 5 seconds, 7 seconds, 10 seconds, 11 seconds, 15 seconds, 25 seconds, 30 seconds, 45 seconds, or 60 seconds. In some embodiments, the duration of providing the nitrogen precursor in the reaction chamber is shorter than 60 seconds, shorter than 40 seconds, shorter than 20 seconds, shorter than 10 seconds, shorter than 4 seconds, or about 3 seconds. In some embodiments, the nitrogen precursor pulse time can be shorter than 60 seconds, shorter than 40 seconds, shorter than 25 seconds, shorter than 15 seconds, shorter than 8 seconds, shorter than 5 seconds, or shorter than 2 seconds.

[0117] In some embodiments, the transition metal precursor can be heated before being provided to the reaction chamber. In some embodiments, the reactant can be heated before being provided to the reaction chamber. In some embodiments, the reactant can be maintained at ambient temperature before being provided to the reaction chamber.

[0118] Stages 104 and 106 performed in any order can form a deposition cycle, resulting in the deposition of a transition metal nitride. In some embodiments, the two stages of transition metal nitride deposition can be repeated, i.e., providing a transition metal precursor and a reactant (cycle 108) in the reaction chamber (104 and 106). Such embodiments include multiple deposition cycles. The thickness of the deposited transition metal nitride-containing material can be adjusted by adjusting the number of deposition cycles. The deposition cycle (cycle 108) can be repeated until the desired transition metal nitride thickness is obtained. For example, about 150, 150, 250, 500, 750, 1000, 1200, 1500, or 2000 deposition cycles can be performed.

[0119] The amount of transition metal nitride deposited during one cycle (growth per cycle) varies depending on the process conditions and can be, for example, from about To date To date For example, from about To date Or from about To date For example, the growth rate can be about In some embodiments, the growth rate of the transition metal nitride-containing layer can be, for example, from about To date Or from about To date Depending on the deposition conditions, deposition cycle number, etc., a layer containing transition metal nitride of variable thickness can be deposited. For example, the thickness of the layer containing transition metal nitride can be between about 0.5nm and 60nm, or between about 1nm and 50nm, or between about 0.5nm and 25nm, or between about 1nm and 50nm, or between about 10nm and 60nm. The transition metal nitride layer can have a thickness of, for example, about 0.2nm, 0.3nm, 0.5nm, 1nm, 1.5nm, 2nm, 2.5nm, 3nm, 3.5nm, 4nm, 4.5nm, 5nm, 6nm, 8nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 50nm, 70nm, 85nm or 100nm. The desired thickness can be selected according to the application in question.

[0120] The transition metal precursor and the nitrogen precursor may be provided to the reaction chamber in separate steps (104 and 106).

[0121] Figure 1B An embodiment according to the invention is shown, in which steps 104 and 106 are separated by purge steps 105 and 107. In such an embodiment, the deposition cycle includes one or more purge steps 103, 105. During the purge steps, the precursors and / or reactants may be temporarily separated from each other by an inert gas such as argon (Ar), nitrogen (N2) or helium (He) and / or vacuum pressure. The separation of the transition metal precursor and the nitrogen precursor may alternatively be spatial. During stages 102 and 104, the temperature and / or pressure in the reaction chamber may be combined with the above Figure 1A Any pressure and temperature described above are the same or similar. Likewise, the deposition cycle 108 may be repeated similarly to Figure 1A to be executed by the embodiment of the present invention.

[0122] Purging reaction chamber 103,105 can prevent or alleviate the gas phase reaction between transition metal precursor and nitrogen precursor, and makes possible self-saturation surface reaction possible.Excess chemical substance and reaction byproduct (if any) can be removed from substrate surface before substrate contacts with next reaction chemical substance, for example, by purging reaction chamber or by moving substrate.However, in some embodiments, substrate can be moved to contact transition metal precursor and nitrogen precursor respectively.Because in some embodiments, reaction may be self-saturated, it may not be necessary to carry out strict temperature control to substrate and carry out accurate dosage control to precursor.However, substrate temperature preferably makes incident gas substance not condense into monolayer or multilayer, and also can not be thermally decomposed on the surface.

[0123] The duration of the purge can be, for example, 0.1 seconds, 0.5 seconds, 1 second, 2 seconds, 5 seconds, 7 seconds, 10 seconds, 15 seconds, 25 seconds, 30 seconds, 45 seconds or 60 seconds. The length of the purge can depend on the processing parameters used during the method, such as the precursors used, chamber pressure, temperature, etc.

[0124] When method 100 is performed, a transition metal nitride is deposited onto a substrate. The deposition process according to the present disclosure is a cyclic deposition process and may include a cyclic CVD, ALD, or a hybrid cyclic CVD / ALD process. For example, in some embodiments, the growth rate of a particular ALD process may be lower than that of a CVD process. One method of increasing the growth rate may be to operate at a deposition temperature higher than that typically employed in an ALD process, resulting in some portions of a chemical vapor deposition process, but still utilizing the sequential introduction of a transition metal precursor and a nitrogen precursor. Such a process may be referred to as cyclic CVD. In some embodiments, a cyclic CVD process may include introducing two or more precursors into a reaction chamber, wherein there may be an overlap time between the two or more precursors in the reaction chamber, resulting in an ALD component of the deposition and a CVD component of the deposition. This is referred to as a hybrid process. According to a further example, a cyclic deposition process may include a continuous flow of a precursor or reactant and periodic pulsation of another chemical component into the reaction chamber.

[0125] In some embodiments, a transition metal precursor is contacted with a substrate surface 104, excess transition metal precursor is partially or substantially completely removed by an inert gas or vacuum 105, and a nitrogen precursor is contacted with the substrate surface containing the transition metal precursor. The transition metal precursor may be contacted with the substrate surface 104 in one or more pulses. In other words, the pulse of the transition metal precursor may be repeated 104. The transition metal precursor on the substrate surface may react with the nitrogen precursor to form a transition metal nitride on the substrate surface. The pulse of the nitrogen precursor may also be repeated 106. In some embodiments, a nitrogen precursor may first be provided in a reaction chamber at stage 106. Thereafter, the reaction chamber 105 may be purged, and the transition metal precursor 104 may be provided in the reaction chamber in one or more pulses.

[0126] In some embodiments, the transition metal nitride layer according to the present disclosure may have a resistivity lower than about 600 μΩ·cm. The thickness of the layer having such a resistivity may be, for example, from about 10 nm to about 25 nm.

[0127] The resistivity of the transition metal nitride layer can be reduced by using a post-deposition anneal. The annealing can be performed directly after the transition metal nitride layer is deposited, i.e., without depositing an additional layer. Alternatively, the annealing can be performed after the additional layer is deposited. The transition metal nitride layer can be covered before annealing. The covering layer can include, consist essentially of, or consist of silicon nitride. An annealing temperature from about 320°C to about 500°C can be used. For example, the annealing temperature can be 330°C, 350°C, 380°C, 400°C, 430°C, or 450°C or 470°C. The annealing can be performed in a gas atmosphere including, consisting essentially of, or consisting of argon, an argon-hydrogen mixture, hydrogen, nitrogen, or a nitrogen-hydrogen mixture. The duration of the annealing can be from about 1 minute to about 60 minutes, for example, 5 minutes, 20 minutes, 30 minutes, or 45 minutes. The annealing can be performed at a pressure of 0.05 to 760 Torr. For example, the pressure during annealing may be about 1 Torr, about 10 Torr, about 100 Torr, or about 500 Torr.

[0128] Figure 1C Another embodiment of the method according to the present disclosure is described. In this embodiment, similar to Figure 1A and 1B In the embodiment of the present invention, a substrate is provided into a reaction chamber 102, a transition metal precursor is provided into a reaction chamber 104, and a nitrogen precursor is provided into a reaction chamber 106. In addition to the two precursors of stages 104 and 106, an auxiliary reactant is provided into the reaction chamber at stage 110. Without limiting the present invention to any particular theory, according to the present invention, the auxiliary reactant can affect the cyclic deposition process by reducing the amount of carbon in the transition metal nitride-containing material.

[0129] In embodiments including providing an auxiliary reactant to the deposition chamber 110, the transition metal precursor, the nitrogen precursor, and the auxiliary reactant may be provided in different orders and frequencies. In some embodiments, providing the transition metal precursor 104 and the nitrogen precursor 106 to the reaction chamber may be performed several times before providing the auxiliary reactant to the reaction chamber 110. Thus, the method includes a sub-cycle indicated by cycle 108. For example, at stage 110, before the auxiliary reactant is provided to the reaction chamber, the sub-cycle 108 may be performed 2 to 60 times, such as 5, 10, 15, 20, 25, 30, or 50 times.

[0130] After providing the auxiliary reactant into the reaction chamber 110, the process can loop back to providing the nitrogen precursor into the reaction chamber 106 via loop 111, or the process can loop back to providing the transition metal precursor into the reaction chamber 104 via loop 112. The loop 111 of providing the nitrogen precursor into the reaction chamber 106 and providing the auxiliary reactant into the reaction chamber 110 can be performed one or more times. For example, before the deposition process ends, or before the process loops back via loop 112 to provide the transition metal precursor into the reaction chamber 104, the loop 111 can be performed 2 to 50 times, such as 3, 5, 10, 15, 20, or 25 times.

[0131] The process may also be performed by repeating only cycle 112. Thus, in some embodiments, a transition metal precursor is provided to the reaction chamber 104, a nitrogen precursor is provided to the reaction chamber 106, an auxiliary reactant is provided to the reaction chamber 110, and the process loops back to providing the transition metal precursor to the reaction chamber 104. Each of stages 104, 106, and 110 may include one or more pulses of precursors or reactants, as appropriate. The precursors and reactants may be provided to the reaction chamber in a sequential manner. After each precursor and / or reactant pulse, the reaction chamber may be purged, Figure 1C In the embodiment including only loop 112, the

[0132] The unit cycle of providing transition metal precursor 104, nitrogen precursor 106, and auxiliary reactant 110 may be repeated at least once. The unit cycle may be repeated 2 to about 500 times, for example 10, 20, 40, 80, 100, 150, 250, or 400 times.

[0133] In some embodiments, the transition metal nitride layer according to the present disclosure may be a layer containing molybdenum nitride and have a resistivity of less than about 600 μΩ·cm, or less than 500 μΩ·cm, or less than 300 μΩ·cm, or less than 250 μΩ·cm, or less than 200 μΩ·cm, or less than 100 μΩ·cm. The thickness of the layer having the resistivity may be, for example, from about 10 nm to about 20 nm, or less than 10 nm.

[0134] Figure 1DAn embodiment according to the present disclosure is shown, wherein the process includes providing an auxiliary reactant to the reaction chamber 110 after providing a transition metal precursor to the reaction chamber 104. For example, in stage 102, a substrate comprising a thermal oxide may be provided to the reaction chamber and heated to a temperature of 350°C. Thereafter, in stage 104, a transition metal precursor such as a molybdenum precursor comprising an aromatic ligand may be provided to the reaction chamber for 10 to 20 seconds. Then, the reaction chamber may be purged for 3 to 10 seconds, and an auxiliary reactant including a halogenated hydrocarbon may be provided to the reaction chamber 110. The auxiliary reactant pulse time may be from about 1 second to about 15 seconds, after which the reaction chamber may be purged again for 3 to 10 seconds. Then, in stage 106, a nitrogen precursor such as NH3 or hydrazine, which includes only, for example, hydrogen and nitrogen, may be provided to the reaction chamber. In the process of providing the nitrogen precursor to the reaction chamber, the temperature may be higher than 300°C, for example, to 320°C to 350°C. The pulse time of the nitrogen precursor may be 2 to 8 seconds. The reaction chamber may then be purged and a new deposition unit cycle may begin via cycle 112 to again provide the transition metal precursor 102. The deposition process may include 50 to 100 unit cycles.

[0135] For clarity, the sequence of stages described in Figures A to D in Figure 1 is only exemplary, and the sequence of precursors and reactants and the cycle repetition can be selected according to specific embodiments. Specifically, in some embodiments, providing nitrogen precursor 106 at the beginning of the process may be beneficial to the growth of the material layer.

[0136] The properties of the transition metal nitride containing material depend on the deposition parameters, such as the precursors and reactants, the cycling scheme and the temperature during deposition. For example, for molybdenum nitride, a carbon content of 10 atomic % or less, such as about 5 atomic % or about 7 atomic %, can be achieved.

[0137] The ratio of nitrogen to transition metal in the deposited material can vary. In some embodiments, the ratio of nitrogen to metal can be about 0.7 to 1.0. However, in some embodiments, the ratio of nitrogen to metal can be about 0.5, or about 0.3, which means that the material can have a higher amount of metal compared to nitrogen. A higher metal content relative to nitrogen may be associated with a lower carbon content.

[0138] Figure 2An exemplary structure or portion of a device 200 according to the present disclosure is shown. The portion of the device or structure 200 includes a substrate 202, a transition metal nitride layer 204, and an optional intermediate layer 206 between (e.g., in contact with one or both) the substrate 202 and the transition metal nitride layer 204. The substrate 202 can be or include any substrate material described herein, such as a dielectric or insulating layer. For example, the dielectric or insulating layer can be a high-k material, such as a metal oxide. In some embodiments, the dielectric constant of the high-k material is higher than the dielectric constant of silicon oxide. Exemplary high-k materials include hafnium oxide (HfO2), tantalum oxide (Ta2O5), zirconium oxide (ZrO2), titanium oxide (TiO2), hafnium silicate (HfSiO x ), aluminum oxide (Al2O3), lanthanum oxide (La2O3), titanium nitride, and a mixture / stack comprising one or more of such layers. Alternatively, the substrate material may comprise a metal such as Cu, Co, W or Mo.

[0139] The transition metal nitride layer 204 can be formed according to the methods described herein. In an embodiment where the intermediate layer 206 is formed, a cyclic deposition process can be used to form the intermediate layer 206. In some embodiments, the transition metal nitride layer 204 can mainly include, for example, at least 50 atomic %, at least 70 atomic %, at least 90 atomic % or at least 95 atomic % of transition metals and nitrides, such as molybdenum nitride, praseodymium tungsten nitride or niobium nitride. In some embodiments, the transition metal nitride layer can be deposited directly on the substrate. In such an embodiment, there is no intermediate layer. As a further alternative, the structure or device according to the present disclosure can include more than one layer between the substrate and the transition metal nitride layer.

[0140] Figure 3 A deposition assembly 300 according to the present disclosure is shown in schematic form. The deposition assembly 300 can be used to perform the methods described herein and / or form the structures or devices described herein or portions thereof.

[0141] In the illustrated example, deposition assembly 300 includes one or more reaction chambers 302, a precursor injector system 301, a transition metal precursor container 304, a nitrogen precursor container 306, an auxiliary reactant source 308, an exhaust source 310, and a controller 312. Deposition assembly 300 may include one or more additional gas sources (not shown), such as an inert gas source, a carrier gas source, and / or a purge gas source.

[0142] Reaction chamber 302 may include any suitable reaction chamber, such as an ALD or CVD reaction chamber as described herein.

[0143] The transition metal precursor container 304 may include a container and one or more transition metal precursors described herein - alone or mixed with one or more carrier gases (e.g., inert gases). The nitrogen precursor container 306 may include a container and one or more nitrogen precursors as described herein - alone or mixed with one or more carrier gases. The auxiliary reactant source 308 may include an auxiliary reactant or its precursor, as described herein. Although three source containers 304-308 are shown, the deposition assembly 300 may include any suitable number of source containers. The source containers 304-308 may be coupled to the reaction chamber 302 via pipelines 314-318, and the pipelines 314-318 may each include a flow controller, a valve, a heater, etc. In some embodiments, the transition metal precursor in the transition metal precursor container 304, the nitrogen precursor in the nitrogen precursor container 306, and / or the auxiliary reactant in the auxiliary reactant container 308 may be heated. In some embodiments, the container is heated so that the precursor or reactant reaches a temperature between about 30° C. and about 160° C., such as between about 100° C. and about 145° C., such as 85° C., 100° C., 110° C., 120° C., 130° C., or 140° C. Each container can be heated to a different temperature depending on the properties of the precursor or reactant, such as thermal stability and volatility.

[0144] The exhaust source 310 may include one or more vacuum pumps.

[0145] The controller 312 includes electronic circuits and software to selectively operate valves, manifolds, heaters, pumps and other components included in the deposition assembly 300. Such circuits and components operate to introduce precursors, reactants and purge gases from respective sources. The controller 312 can control the timing of gas pulse sequences, the temperature of the substrate and / or the reaction chamber 302, the pressure within the reaction chamber 302, and various other operations to provide the correct operation of the deposition assembly 300. The controller 312 may include control software to control the flow of precursors, reactants and purge gases into and out of the reaction chamber 302 with electric or pneumatic control valves. The controller 312 may include modules that perform specific tasks, such as software or hardware components. The modules may be configured to reside on an addressable storage medium of the control system and configured to perform one or more processes.

[0146] Other configurations of the deposition assembly 300 are possible, including different numbers and types of precursor and reactant sources. In addition, it should be understood that many arrangements of valves, conduits, precursor sources, and auxiliary reactant sources can be used to achieve the goal of selectively and in a coordinated manner supplying gases into the reaction chamber 302. In addition, as a schematic representation of the deposition assembly, many components have been omitted for simplicity of illustration, and these components may include, for example, various valves, manifolds, purifiers, heaters, containers, vents, and / or bypasses.

[0147] During operation of deposition assembly 300, a substrate such as a semiconductor wafer (not shown) is transferred from, for example, a substrate handling system to reaction chamber 302. Once the substrate is transferred to reaction chamber 302, one or more gases such as precursors, reactants, carrier gases, and / or purge gases are introduced into reaction chamber 302 from a gas source.

[0148] In some embodiments, the transition metal precursor is supplied in pulses, the auxiliary reactant is supplied in pulses, and the reaction chamber is purged between successive pulses of the transition metal precursor and the auxiliary reactant.

[0149] The exemplary embodiments disclosed above do not limit the scope of the present invention, as these embodiments are merely examples of embodiments of the present invention, and the scope of the present invention is defined by the appended claims and their legal equivalents. Any equivalent embodiments are within the scope of the present invention. In addition to those shown and described herein, various modifications of the present disclosure, such as replaceable useful combinations of the described elements, will become apparent to those skilled in the art from the description. Such modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for depositing a material containing a transition metal nitride on a substrate by a cyclic deposition process, the method comprising: providing a substrate in a reaction chamber; providing an organometallic transition metal precursor to a reaction chamber in a gas phase; Providing auxiliary reactants to the reaction chamber in gas phase; as well as A nitrogen precursor is provided in a gas phase into a reaction chamber to form a transition metal nitride on a substrate; wherein, The transition metal precursor includes a transition metal from any one of Groups 4 to 6 of the Periodic Table of Elements, wherein the auxiliary reactant comprises a halogen selected from bromine and iodine, and The auxiliary reactant comprises 1,2-dihaloalkane, 1,2-dihaloalkene, 1,2-dihaloalkyne or 1,2-dihaloaromatic hydrocarbon.

2. The method according to claim 1, wherein: The transition metal precursor includes a Group 6 transition metal.

3. The method according to claim 2, wherein: The Group 6 transition metal is selected from molybdenum and tungsten.

4. The method according to claim 2, wherein: The Group 6 transition metal is molybdenum.

5. The method according to claim 4, wherein: The transition metal precursor contains only molybdenum, carbon and hydrogen.

6. The method according to claim 5, wherein: The transition metal precursor comprises benzene or cyclopentadienyl.

7. The method according to claim 1, wherein: The nitrogen precursor includes only nitrogen and hydrogen.

8. The method according to claim 1, wherein: The nitrogen precursor is selected from NH3, NH2NH2 and a mixture of gaseous H2 and N2.

9. The method according to claim 1, wherein: The two halogen atoms of the auxiliary reactant are the same halogen.

10. A method for depositing a material containing a transition metal nitride on a substrate by a cyclic deposition process, the method comprising: providing a substrate in a reaction chamber; providing an organometallic transition metal precursor to a reaction chamber in a gas phase; Providing auxiliary reactants to the reaction chamber in gas phase; as well as A nitrogen precursor is provided in a gas phase into a reaction chamber to form a transition metal nitride on a substrate; wherein, The transition metal precursor includes a transition metal from any one of Groups 4 to 6 of the Periodic Table of Elements, The auxiliary reactant includes 1,2-diiodoethane.

11. The method according to claim 1, wherein: The auxiliary reactant is used to adjust the resistivity of the deposited transition metal nitride material.

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