Method and system for depositing metal phosphides

Abstract

The present disclosure relates to methods and apparatus for depositing a metal phosphide-containing material on a substrate by a cyclic deposition process. The method includes providing a substrate in a reaction chamber, providing a metal halide precursor in a vapor phase into the reaction chamber; and providing a second precursor in a vapor phase into the reaction chamber to form the metal phosphide-containing material on the substrate.

Description

[0001] Parties to the Joint Research Agreement

[0002] The invention claimed herein was made as a result of, on behalf of, and / or in connection with a joint research agreement between the University of Helsinki and ASM Microchemistry Oy. The agreement was in force on and before the date on which the claimed invention was made, and the claimed invention is the result of activities carried out within the scope of the agreement. Technical Field

[0003] The present invention relates to methods and systems for manufacturing semiconductor devices. More specifically, the present disclosure relates to methods and assemblies for depositing metal phosphide materials on substrates by a cyclic deposition process, and layers containing metal phosphide materials. Background Art

[0004] Metal phosphides play an important role in microelectronics as semiconductors. Some metal phosphides are also metallic materials with potential for a variety of applications (e.g. hydrogen evolution reaction, lithium-ion battery anodes and MOSCAP). Especially in modern microelectronic devices, materials must be deposited as high-quality films on large and complex 3D structures. Cyclic deposition methods such as atomic layer deposition are the best available film deposition methods for these purposes. Currently, there are few atomic layer deposition methods for metal phosphides and most use highly toxic PH 3 Gas is used as the phosphide source.

[0005] 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 or constituted prior art at the time the present invention was made. Summary of the invention

[0006] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the detailed description of the exemplary embodiments of the present disclosure below. This summary is not intended to identify the 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.

[0007] Various embodiments of the present disclosure relate to methods of depositing a metal phosphide-containing material on a substrate, metal phosphide layers, semiconductor structures and devices including the layers, and deposition assemblies for depositing a metal phosphide-containing material on a substrate.

[0008] In a first aspect, a method for forming a layer comprising a metal phosphide on a substrate by a cyclic deposition process is disclosed. The method comprises providing a substrate into a reaction chamber and performing at least one deposition cycle. Each deposition cycle comprises providing a metal halide precursor into the reaction chamber in a gas phase and providing a second precursor into the reaction chamber in a gas phase to form a layer comprising a metal phosphide on the substrate. In the method, the second precursor comprises an alkylsilylphosphine or a silylphosphine.

[0009] In another aspect, a metal phosphide layer produced by a cyclic deposition process is disclosed. The cyclic deposition process includes providing a substrate in a reaction chamber, providing a metal halide precursor in a vapor phase into the reaction chamber, and providing a second precursor in a vapor phase into the reaction chamber to form a metal phosphide on the substrate. In the process, the second precursor comprises an alkylsilylphosphine or a silylphosphine.

[0010] In another aspect, a semiconductor structure including a metal phosphide layer produced by a cyclic deposition process is disclosed. The cyclic deposition process includes providing a substrate in a reaction chamber, providing a metal halide precursor in a gas phase into the reaction chamber, and providing a second precursor in a gas phase into the reaction chamber to form a metal phosphide on the substrate. In the process, the second precursor comprises an alkylsilylphosphine or a silylphosphine.

[0011] In yet another aspect, a semiconductor device including a metal phosphide layer produced by a cyclic deposition process is disclosed. The cyclic deposition process includes providing a substrate in a reaction chamber, providing a metal halide precursor in a vapor phase into the reaction chamber, and providing a second precursor in a vapor phase into the reaction chamber to form a metal phosphide on the substrate. In the process, the second precursor comprises an alkylsilylphosphine or a silylphosphine.

[0012] In another aspect, a deposition assembly for depositing a metal phosphide on a substrate is disclosed. The deposition assembly includes: one or more reaction chambers, which are constructed and arranged to hold a substrate; a precursor injector system, which is constructed and arranged to provide a metal halide precursor and a second precursor to the reaction chamber in a gas phase, wherein the second precursor includes an alkylsilylphosphine or a silylphosphine. The deposition assembly also includes a precursor container, which is constructed and arranged to hold the metal halide precursor, and the assembly is constructed and arranged to provide the metal halide precursor and the second precursor to the reaction chamber via the precursor injector system to deposit the metal phosphide on the substrate.

[0013] In the present disclosure, any two numbers of a variable may constitute a possible range for the variable, and any range indicated may or may not include the endpoints.

[0014] Furthermore, any values ​​of the variables indicated (whether or not they are expressed as "about") may refer to exact values ​​or approximate values, and include equivalents, and may refer to average values, medians, representative values, multiple values, etc. Furthermore, in the present disclosure, the terms "comprising," "consisting of," and "having" independently refer to "generally or broadly including," "including," "consisting essentially of," or "consisting of" in some embodiments. In the present disclosure, in some embodiments, any defined meaning does not necessarily exclude the ordinary and customary meaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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 explain the principles of the present disclosure. In the accompanying drawings,

[0016] Figure 1A and Figure 1B A block diagram of an exemplary embodiment of a method according to the present disclosure is shown.

[0017] Figure 2 is a schematic diagram of a deposition assembly according to the present disclosure.

[0018] 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. DETAILED DESCRIPTION

[0019] Although certain embodiments and examples are disclosed below, it will be appreciated by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments and / or uses of the present invention and their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specifically disclosed embodiments described below.

[0020] In the deposition methods according to the present disclosure, a metal phosphide material is deposited. Thus, the material deposited according to the present disclosure comprises a metal phosphide. Metal phosphide herein refers to a metal in combination with a phosphide. In some embodiments, the material deposited according to the present disclosure consists of or consists essentially of a metal phosphide. In some embodiments, at least 60% of the metal phosphide is deposited as a metal phosphide. In some embodiments, at least 80% or at least 90% of the metal phosphide is deposited as a metal phosphide. In some embodiments, the layer comprising the metal phosphide does not contain elemental metal. In one embodiment, the metal phosphide has a metal phosphide according to the general formula M 2 In one embodiment, the metal phosphide has a structure according to the general formula MP, wherein M is a metal.

[0021] The composition of the material deposited according to the present disclosure can vary according to the process. In some embodiments, the material deposited according to the present disclosure includes at least one element in addition to the target metal phosphide. Such a material may have properties different from metals useful in certain applications. In some embodiments, the metal phosphide-containing material may include, for example, at least about 60 atomic percent (atomic %) of the target metal phosphide, or at least about 75 atomic % of the target metal phosphide, or about 75 to about 95 atomic % of the target metal phosphide, or about 75 to about 89 atomic % of the target metal phosphide. The metal phosphide-containing material deposited by the method according to the present disclosure may include, for example, at least about 80 atomic %, about 85 atomic %, about 87 atomic %, about 90 atomic %, about 95 atomic %, about 97 atomic % or about 99 atomic % of the target metal phosphide. In some embodiments, the metal phosphide-containing material may be composed of or substantially composed of the target metal phosphide. The material composed of the metal phosphide may include an acceptable amount of impurities, such as carbon, nitrogen, oxygen, chlorine or other halogens, and / or hydrogen, which may be derived from one or more precursors used to deposit the metal phosphide-containing material.

[0022] In some embodiments, the metal phosphide-containing material may contain 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 metal phosphide-containing material may contain less than about 20 atomic%, less than about 15 atomic%, less than about 10 atomic%, less than about 8 atomic%, less than about 6 atomic%, less than about 5 atomic%, less than 4.5 atomic%, or less than about 3 atomic% impurity carbon.

[0023] In some embodiments, the metal phosphide-containing material may form a layer. In such embodiments, the metal phosphide forms a metal phosphide layer. As used herein, a "metal phosphide layer" may be a material layer comprising a metal phosphide. As used herein, the terms "layer" and / or "film" may refer to any continuous or discontinuous structure and material, such as a material 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 clusters. 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, the seed layer may also be substantially or completely continuous.

[0024] As used herein, the term "substrate" may refer to any one or more underlying materials that can be used to form or on which a device, circuit, material, or material layer can be formed. The substrate may include a bulk material, such as silicon (e.g., single crystal silicon), other Group 14 materials (e.g., germanium), or other semiconductor materials (e.g., Group II-VI or Group III-V semiconductor materials). The substrate may include one or more layers covering the bulk material. The substrate may include various topological structures, such as gaps, including grooves, lines, trenches, or spaces between raised portions (e.g., fins) formed in or on at least a portion of the substrate layer. The substrate may include nitrides (e.g., TiN), oxides, insulating materials, dielectric materials, conductive materials, metals (e.g., tungsten, ruthenium, molybdenum, cobalt, aluminum, or copper) or metallic materials, crystalline materials, epitaxial materials, heteroepitaxial materials, and / or single crystal materials. In some embodiments of the present disclosure, the substrate includes silicon. As described above, in addition to silicon, the substrate may include other materials. Other materials may form layers.

[0025] The present disclosure relates to the deposition of materials from the gas phase.Thus, a gaseous metal halide precursor and a second precursor are used in the method according to the present disclosure.

[0026] 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 consist of a single gas or a gas mixture depending on the context. The metal halide precursor may be provided to the reaction chamber in a gas phase. The second 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 an appreciable extent. Exemplary inert gases include He and Ar and any combination thereof. In some cases, molecular nitrogen may be an inert gas. Gases other than process gases, i.e., gases that are not introduced through a precursor injector system, other gas distribution devices, etc., may be used, for example, to seal a reaction space and may include a sealing gas.

[0027] 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 (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 metal-containing or semi-metallic materials, 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.

[0028] The process may include one or more cyclic phases. For example, pulses of the metal halide precursor and the second precursor 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, the reactant may be provided continuously in the reaction chamber. In such embodiments, the process includes a continuous flow of the 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.

[0029] 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. Typically, for an ALD process, during each cycle, a precursor is introduced into the reaction chamber and chemically adsorbed or reacted to a deposition surface (e.g., a substrate surface that may include previously deposited material from a previous ALD cycle or other material), forming a monolayer or sub-monolayer of material that is not easily reacted with additional precursors (i.e., a self-limiting reaction). Thereafter, in some cases, another precursor or reactant may be subsequently introduced into the processing chamber for converting the chemically adsorbed precursor to the 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 metal halide precursor to the reaction chamber. In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing the second precursor to the reaction chamber. In some embodiments, the cyclic deposition process includes purging the reaction chamber after providing any precursors or reactants into the reaction chamber.

[0030] The CVD type process can also include a gas phase reaction between two or more precursors and / or reactants. Precursors and reactants can be provided to the reaction space or substrate simultaneously, or provided with pulses that are partially or completely separated. 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, the 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.

[0031] Without limiting the present disclosure to any particular theory, in some embodiments, it is possible to produce a layer with low resistivity, especially when depositing a metal phosphide. The resistivity of the metal phosphide layer according to the present disclosure may be less than 400 μΩ cm, or less than 320 μΩ cm, or less than 250 μΩ cm, or less than 200 μΩ cm. For example, the resistivity of the metal phosphide layer according to the present disclosure may be from about 5 μΩ cm to about 350 μΩ cm, or from about 5 μΩ cm to about 300 μΩ cm, or from about 5 μΩ cm to about 250 μΩ cm, or from 10 μΩ cm to about 200 μΩ cm.

[0032] The growth rate of the metal phosphide layer can be, for example, from about 0.05 to about 1.5 Å / cycle. The growth rate and layer properties may depend on the temperature at which the deposition process is performed. In some embodiments, the growth rate can be about 0.1 Å / cycle, or about 0.2 Å / cycle, or about 0.5 Å / cycle, or about 0.65 Å / cycle, or about 1 Å / cycle. The growth rate can vary during the deposition process.

[0033] In some embodiments, after providing the metal halide precursor and / or the second precursor in the reaction chamber, the reaction chamber is purged. As used herein, the term "purging" may refer to a process of removing gaseous precursors and / or gaseous byproducts from the substrate surface, such as by evacuating the 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 can be performed between two gas pulses that react with each other. However, purge can be performed between two gas pulses that do not react with each other. For example, purge can be provided between pulses of two precursors or between a precursor and a reactant. Purge can avoid or at least reduce the gas phase interaction between the two gases that react with each other. It should be understood that purge can be performed in time or space, or both. For example, in the case of time purge, a purge step can be used, for example, in the time sequence of providing a first precursor to the reactor chamber, providing a purge gas to the reactor chamber, and providing a second precursor to the reactor chamber, wherein the substrate on which the layer is deposited does not move. For example, in the case of space purging, the purging step can take the following form: the substrate is moved from a first position of continuous supply of the first precursor to a second position of continuous supply of the second precursor by a purging gas curtain. The purging time can be, for example, between about 0.01 seconds to about 20 seconds, about 0.05 seconds to about 20 seconds, or about 1 second to about 20 seconds, or about 0.5 seconds to about 10 seconds, or about 1 second to about 7 seconds, such as 1 second, 2 seconds or 3 seconds. However, if necessary, other purging times can be used, such as when highly conformal step coverage is required on extremely high aspect ratio structures or other structures with complex surface morphology, or can be used in specific reactor types (such as batch reactors).

[0034] 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, the increased temperature provides the energy required to form the metal-containing phosphide material in the absence of other external energy sources such as plasma, free radicals or other forms of radiation. In some embodiments, the cyclic deposition process according to the present disclosure is a completely thermal process, that is, it does not include a plasma step. However, in some embodiments, the method includes at least one plasma enhanced step. In some embodiments, the method according to the present disclosure is a plasma enhanced deposition method, such as PEALD or PECVD.

[0035] The method according to the present disclosure includes providing a substrate in a reaction chamber, providing a metal halide precursor in a vapor phase into the reaction chamber, and providing a second precursor in a vapor phase into the reaction chamber to form a metal-containing phosphide material on the substrate.

[0036] The method of depositing a metal phosphide-containing material according to the present invention includes providing a substrate in a reaction chamber. In other words, the substrate is brought into a space where 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 space-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 mass production. In some embodiments, the reaction chamber can be a batch reactor for simultaneously manufacturing multiple substrates. The reaction chamber according to the present disclosure can also be a deposition station in a multi-station chamber.

[0037] Furthermore, in the method according to the present disclosure, the metal halide precursor is provided in a gas phase into the reaction chamber, and the second precursor is provided in a gas phase into the reaction chamber to form a metal phosphide-containing material on the substrate.

[0038] In the method according to the present disclosure, when the metal halide precursor is in the reaction chamber, it can be in the gas phase. The metal halide precursor may be partially gaseous or liquid, or even solid at some point in time before being provided to the reaction chamber. In other words, the metal halide precursor may be a solid, liquid or gas in, for example, a precursor container or other container before being delivered to the reaction chamber. When the precursor is delivered to the reaction chamber, various methods of bringing the precursor into the gas phase can be used. These methods may include, for example, a heater, an evaporator, a gas flow, or applying a low pressure or any combination thereof. Therefore, the method according to the present disclosure may include heating the metal halide precursor before providing it to the reaction chamber.

[0039] In some embodiments, deposition of metal phosphide-containing materials according to the present disclosure is performed at a temperature below about 300° C., or below about 290° C., or below about 280° C. In some embodiments, deposition is performed at a temperature from about 240° C. to about 310° C., such as from about 200° C. to about 300° C., such as at a temperature of about 200° C., about 225° C., or about 250° C.

[0040] In some embodiments, the metal halide precursor is heated to at least 30°C, at least 50°C, or at least 70°C, or at least 90°C, or at least 110°C, or at least 130°C before being provided to the reaction chamber. In some embodiments, the metal halide precursor is heated to at least 160°C, or at least 170°C. The heating can be performed in the precursor container. In some embodiments, the metal halide precursor is heated to at most 190°C, or at most 180°C, or at most 170°C, or at most 150°C before being provided to the reaction chamber. The injector system of the vapor deposition assembly can be heated to improve the gas phase delivery of the metal halide precursor to the reaction chamber.

[0041] 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 moiety that is at least partially incorporated into the compound or element produced by the chemical reaction. The compound or element thus obtained can be deposited on a substrate. A reactant may refer to 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 production of a compound or element, or it may change the properties of the deposited material.

[0042] As used herein, a "metal halide precursor" includes a gas or a material that can be turned into a gaseous state, and can be represented by a chemical formula including a target metal. The target metal refers to the metal in the metal phosphide to be deposited. Examples of the target metal include, for example, an early transition metal, a late transition metal, a lanthanide metal, and a late-transition metal.

[0043] In some embodiments, the metal halide precursor comprises a transition metal for depositing a metal phosphide on a substrate. In some embodiments, the transition metal halide precursor comprises a Group 8-11 transition metal for depositing a Group 8-11 transition metal phosphide on a substrate. In some embodiments, the metal in the metal halide precursor is selected from molybdenum (Mo), chromium (Cr), tungsten (W), nickel (Ni), cobalt (Co), niobium (Nb), copper (Cu), titanium (Ti), palladium (Pd), platinum (Pt), zirconium (Zr), hafnium (Hf), vanadium (V), tantalum (Ta), manganese (Mn), rhodium (Rh), iron (Fe), iridium (Ir) and rhenium (Re). In some embodiments, the metal in the metal halide precursor is selected from cobalt, copper, iron, titanium, tantalum, niobium and nickel. In some embodiments, the metal in the metal halide precursor is selected from scandium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd). In some embodiments, the transition metal in the metal halide precursor is selected from iron, cobalt, nickel and copper. In some embodiments, the metal halide precursor includes a lanthanide metal for depositing a lanthanide metal phosphide on a substrate. In some embodiments, the transition metal in the metal halide precursor can be cobalt. In some embodiments, the metal halide precursor consists only of a metal and a halogen. In some embodiments, the metal halide precursor includes a transition metal, a halogen and a ligand that forms an adduct.

[0044] In some embodiments, the metal halide precursor is a metal halide precursor. In some embodiments, the metal halide is composed of a transition metal, a halogen, and a ligand that forms an adduct. In some embodiments, the halogen in the metal halide is selected from chlorine, iodine, fluorine, and bromine. In some embodiments, the halogen in the metal halide is chloride. In some embodiments, the metal halide precursor includes an amine ligand. In some embodiments, the metal halide precursor includes an alkylamine ligand. In some embodiments, the metal halide precursor includes cobalt dichloride tetramethylethylenediamine.

[0045] In some embodiments, the metal halide precursor is provided as a mixture of two or more compounds. In the mixture, other compounds except the metal halide precursor can be inert compounds or elements. In some embodiments, the metal halide precursor is provided as a composition. Compositions suitable for use as compositions can include a metal compound and an effective amount of one or more stabilizers. The composition can be a solution or a gas under standard conditions.

[0046] In some embodiments, the second precursor comprises phosphorus. In some embodiments, the second precursor comprises a x (SiR 3 ) y wherein x is an integer from 0 to 2, y=3-x, and R is hydrogen or a C1-C10 alkyl group. In some embodiments, the alkyl group is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, and any branched or cyclic variants thereof. In some embodiments, the second precursor comprises tris(trimethylsilyl)phosphine.

[0047] Similar to the metal halide precursor, the second precursor may be heated before being provided to the reaction chamber. The temperature to which the second precursor is heated depends on the nature of the second precursor.

[0048] In some embodiments, before or during the second precursor is provided to the reaction chamber, it is heated to at least 20°C, at least 25°C to at least 50°C, or at least 70°C, or at least 90°C, or at least 100°C, or at least 110°C. The heating can be performed in the precursor container. In some embodiments, before or during the second precursor is provided to the reaction chamber, it is heated to at most 120°C, or at most 100°C, or at most 80°C, or at most 60°C. The injector system of the vapor deposition assembly can be heated to improve the gas phase delivery of the second precursor to the reaction chamber.

[0049] In some embodiments, the process is an ABC type process. The process for forming a metal phosphide-containing material on a substrate also includes providing a halide precursor in a gas phase to a reaction chamber. The halide precursor is provided to the reaction chamber after the first precursor. In some embodiments, the first precursor may be the same metal halide precursor as disclosed in the present application. In some embodiments, the first precursor includes a metal that can be used in a cyclic deposition process of a metal halide film, but does not necessarily include the halide itself. By adding a halide precursor to the process, an intermediate compound MX is formed, wherein M is a metal and X is a halide. In some embodiments, the halide includes fluorine. In some embodiments, the halide includes chlorine.

[0050] In the next step, when a second precursor is provided into the reaction chamber, the intermediate compound reacts with the phosphine-containing precursor to form a metal phosphide layer on the substrate.

[0051] The metal halide precursor can be selected from any group of compounds that produce the intermediate compound MX. By using the ABC process, the list of possible metals is broadened because the metal itself does not need to form a volatile halide precursor. Instead, the metal needs to be able to undergo a cyclic deposition process of a metal halide film. In some embodiments, the halide precursor is selected from HF, NH 4 F,TiF 4 , TaF 5, NbF 5 , WF 6 , MoF 6 , HCl, TiCl 4 , SnCl 4 , BiCl 3 , GaCl 3 , ScF 3 , CuCl, PbCl 2 ,AgCl, SF 6 Plasma, other volatile inorganic fluorides, Hfac-ligand + O 3 and any fluorinated ligand + O 3 .

[0052] The following exemplary embodiments depicted in the accompanying drawings further explain the present disclosure. The illustrations given herein are not meant to be actual views of any particular material, structure, device, or apparatus, but are merely schematic representations describing 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 size 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.

[0053] The specific embodiments shown and described are illustrations of the present invention and are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, the traditional manufacturing, connection, preparation and other functional aspects of the system may not be described in detail. In addition, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between the various elements. Many alternative or additional functional relationships or physical connections may exist in actual systems, and / or may not exist in some embodiments.

[0054] It should be understood that the configurations and / or methods described herein are exemplary in nature, and these specific embodiments or examples should not be considered restrictive, as many variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. Therefore, the various actions shown may be performed in the order shown, in other orders, or may be omitted in some cases.

[0055] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts and / or properties disclosed herein, and any and all equivalents thereof.

[0056] Figure 1A and Figure 1BA block diagram of an exemplary embodiment of a method 100 for depositing a metal-containing phosphide material on a substrate surface is shown. In a first stage 102, a substrate is provided to 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 native silicon 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. The metal-containing phosphide material according to the present disclosure may be deposited on a surface of the surface.

[0057] The reaction chamber may form part of an atomic layer deposition (ALD) assembly. The reaction chamber may form part of a chemical vapor deposition (CVD) assembly. The assembly may be a single wafer reactor. Alternatively, the reactor may be a batch reactor. The assembly may include one or more multi-station deposition chambers. 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 metal-phosphide-containing material according to the present disclosure may be deposited in a cross-flow reaction chamber. The metal-phosphide-containing material according to the present disclosure may be deposited in a showerhead reaction chamber.

[0058] A metal halide precursor is provided in a reaction chamber containing a substrate 104. Without limiting the present disclosure to any particular theory, the metal halide precursor may be chemically adsorbed on the substrate during the time the metal halide precursor is provided into the reaction chamber. The duration of providing the metal halide precursor into the reaction chamber (metal halide precursor pulse time) may be, for example, 0.5 seconds, 1 second, 1.5 seconds, 2 seconds, 3 seconds, 4 seconds, or 5 seconds.

[0059] In the second deposition phase 106 of the method 100, a second precursor is provided in the reaction chamber. In some embodiments, the second precursor includes phosphorus. The duration of providing the second precursor to the reaction chamber (second precursor pulse time) can be, for example, 0.5 seconds, 1 second, 1.5 seconds, 2 seconds, 3 seconds, 4 seconds, or 5 seconds.

[0060] The stages of providing the metal halide precursor 104 and providing the second precursor 106 can be performed in any order. The stages of providing the metal halide precursor 104 and providing the second precursor 106 can constitute a deposition cycle, resulting in the deposition of a metal-containing phosphide material. In some embodiments, the two stages of metal-containing phosphide material deposition can be repeated, i.e., providing the metal halide precursor and the second precursor (104 and 106) in the reaction chamber (cycle 108). These embodiments include multiple deposition cycles. The thickness of the deposited metal-containing phosphide material can be adjusted by adjusting the number of deposition cycles. The deposition cycle (cycle 108) can be repeated until the desired thickness of the metal-containing phosphide material is obtained. For example, about 50, 100, 200, 300, 400, 500, 700, 800, 1000, 1200, 1500, 2000, 2400 or 3000 deposition cycles can be performed. Cyclic deposition can result in the formation of a metal-containing phosphide layer. The layer may be substantially continuous or continuous.

[0061] In some embodiments, the cyclic deposition process includes alternately and sequentially providing a metal halide precursor and a second precursor in a reaction chamber. Figure 1B As shown, the reaction chamber is purged between precursors 105, 107. In such an embodiment, a deposition cycle may be considered to include stages 104, 105, 106, and 107. As described above, the deposition cycle may be repeated 108 multiple times to obtain a desired thickness of the metal-containing phosphide material.

[0062] The metal halide precursor and the second precursor may be provided in the reaction chamber in separate steps (104 and 106). Figure 1B 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 step, the precursors and / or reactants can be temporarily separated from each other by an inert gas such as argon (Ar), nitrogen (N2), or vacuum pressure or by evacuating the system. 2 ) or helium (He). The separation of the metal halide precursor and the second precursor may also be spatial.

[0063] Purging the reaction chambers 103, 105 can prevent or mitigate the gas phase reaction between the metal halide precursor and the second precursor, and enable possible self-limiting or saturated surface reactions. Excess chemicals and reaction byproducts (if any) can be removed from the substrate surface before the substrate contacts the next reaction chemical, for example by purging the reaction chamber or by moving the substrate. However, in some embodiments, the substrate can be moved to contact the metal halide precursor and the second precursor, respectively. Because in some embodiments, the reaction may be self-limiting or saturated, strict temperature control of the substrate and precise dosage control of the precursor may not be required. However, the substrate temperature is preferably such that the incident gaseous material does not condense into a monolayer or multilayer, nor does it thermally decompose on the surface.

[0064] When method 100 is performed, a metal phosphide-containing material is deposited onto a substrate. The deposition process may be a cyclic deposition process and may include 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 way to increase 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 metal halide precursor and a second 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 overlapping period of time between the two or more precursors in the reaction chamber, resulting in an ALD component of deposition and a CVD component of deposition. This is referred to as a hybrid process. According to a further example, a cyclic deposition process may include a continuous flow of one reactant or precursor and periodic pulses of another chemical component into the reaction chamber. The temperature and / or pressure within the reaction chamber during step 104 may be the same or similar to any pressure and temperature described above in conjunction with step 102.

[0065] In some embodiments, a metal halide precursor is contacted with a substrate surface 104, excess metal halide precursor is partially or substantially completely removed by an inert gas or vacuum 105, and a second precursor is contacted with the substrate surface containing the metal halide precursor. The metal halide precursor may be contacted with the substrate surface in one or more pulses 104. In other words, the pulses 104 of the metal halide precursor may be repeated before pulsing the second precursor. The metal halide precursor on the substrate surface may react with the second precursor to form a metal phosphide-containing material on the substrate surface. The pulses 106 of the second precursor may also be repeated. In some embodiments, the second precursor may first be provided in a reaction chamber 106. Thereafter, the reaction chamber may be purged 105, and the metal halide precursor may be provided in the reaction chamber in one or more pulses 104.

[0066] Figure 2A deposition assembly 200 according to the present disclosure is shown in schematic form. The deposition assembly 200 can be used to perform the methods described herein and / or form the structures or devices described herein or portions thereof.

[0067] In the example shown, the deposition assembly 200 includes one or more reaction chambers 202, a precursor injector system 201, a metal halide precursor container 204, a second precursor container 206, an exhaust source 210, and a controller 212. The deposition assembly 200 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.

[0068] Reaction chamber 202 may include any suitable reaction chamber, such as an ALD or CVD reaction chamber as described herein.

[0069] The metal halide precursor container 204 may include a container and one or more metal halide precursors as described herein—alone or mixed with one or more carrier gases (e.g., inert gases). The second precursor container 206 may include a container and a second precursor as described herein—alone or mixed with one or more carrier gases. Although two source containers 204, 206 are shown, the deposition assembly 200 may include any suitable number of source containers. The source containers 204, 206 may be coupled to the reaction chamber 202 via lines 214, 216, which may each include a flow controller, a valve, a heater, etc. In some embodiments, the metal halide precursor in the metal halide precursor container 204 and the second precursor in the second precursor container 206 may be heated. In some embodiments, the containers are heated so that the precursors or reactants reach a temperature, for example, between about 30°C and about 300°C, depending on the nature of the chemical substance in question.

[0070] Exhaust source 210 may include one or more vacuum pumps.

[0071] The controller 212 includes electronic circuits and software to operate valves, manifolds, heaters, pumps and other components included in the deposition assembly 200. Such circuits and components are used to introduce precursors, reactants and purge gases from corresponding sources. The controller 212 can control the timing of the gas pulse sequence, the temperature of the substrate and / or the reaction chamber 202, the pressure in the reaction chamber 202, and various other parameters to provide the correct operation of the deposition assembly 200. The controller 212 may include control software to control the flow of precursors, reactants and purge gases into and out of the reaction chamber 202 electrically or pneumatically. The controller 212 may include modules that perform certain tasks, such as software or hardware components. The module may be configured to reside on an addressable storage medium of the control system and configured to perform one or more processes.

[0072] Other configurations of the deposition assembly 200 are possible, including different numbers and types of precursor and reactant sources. In addition, it should be understood that there are many arrangements of valves, conduits, precursor sources, and auxiliary reactant sources that can be used to achieve the goal of selectively and in a coordinated manner to supply gases into the reaction chamber 202. In addition, as a schematic representation of the deposition assembly, many components are omitted for simplicity of illustration, and these components may include, for example, various valves, manifolds, purifiers, heaters, containers, vents, and / or bypasses.

[0073] During operation of deposition assembly 200, a substrate, such as a semiconductor wafer (not shown), is transferred from, for example, a substrate handling system to reaction chamber 202. Once the substrate is transferred to reaction chamber 202, one or more gases (e.g., precursors, reactants, carrier gases, and / or purge gases) from a gas source are introduced into reaction chamber 202.

[0074] In some embodiments, the metal halide precursor is supplied in pulses, the second precursor is supplied in pulses, and the reaction chamber is purged between successive pulses of the metal halide precursor and the second precursor.

[0075] 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. Various modifications of the present disclosure, such as alternative useful combinations of the described elements, in addition to those shown and described herein, will become apparent to those skilled in the art from this description. These modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for forming a layer comprising a metal phosphide on a substrate, the method comprising: providing a substrate into a reaction chamber; performing at least one deposition cycle, wherein the deposition cycle comprises: providing a metal halide precursor in a vapor phase into the reaction chamber; and providing a second precursor in a gas phase into the reaction chamber; A layer containing a metal phosphide is formed on a substrate, wherein the second precursor contains an alkylsilylphosphine or a silylphosphine.

2. The method according to claim 1, wherein: The metal in the metal halide precursor includes a Group 8 to 11 transition metal.

3. The method according to claim 1, wherein: The metal in the metal halide precursor is selected from the group consisting of cobalt, copper, iron, titanium, tantalum, niobium and nickel.

4. A method according to any one of the preceding claims, wherein: The metal in the metal halide precursor is cobalt.

5. A method according to any one of the preceding claims, wherein: The halide in the metal halide precursor is selected from chlorine, iodine, fluorine and bromine.

6. A method according to any one of the preceding claims, wherein: The halide is chloride.

7. A method according to any one of the preceding claims, wherein: The metal halide precursor comprises an amine ligand.

8. The method according to claim 7, wherein: The amine ligand is an alkylamine ligand.

9. A method according to any one of the preceding claims, wherein: The metal halide precursor includes cobalt dichloride tetramethylethylenediamine.

10. A method according to any one of the preceding claims, wherein: The second precursor comprises a compound having the formula PH x (SiR3) y An alkylsilylphosphine, wherein x is an integer from 0 to 2, y=3-x, and R is hydrogen or a C1-C10 alkyl group.

11. The method according to claim 10, wherein: The alkyl group is selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, and any branched or cyclic variants thereof.

12. A method according to any one of the preceding claims, wherein: The second precursor includes tris(trimethylsilyl)phosphine.

13. A method according to any one of the preceding claims, wherein: The precursors are provided to the reaction chamber in an alternating and sequential manner.

14. A method according to any one of the preceding claims, wherein: The deposition is carried out at a temperature in the range of 180-320°C.

15. The method according to any one of claims 1 to 13, wherein: The deposition is carried out at a temperature below 300°C.

16. A method according to any one of the preceding claims, wherein: The precursor is provided to the reaction chamber in pulses, and the reaction chamber is purged between consecutive precursor pulses.

17. A method according to any one of the preceding claims, wherein: The metal phosphide has a structure according to the general formula M2P, wherein M is a metal.

18. A metal phosphide layer produced according to the method of any preceding claim.

19. The layer according to claim 18, wherein The layer is substantially continuous or substantially pinhole-free.

20. A semiconductor structure comprising a metal phosphide deposited according to the method of claim 1.

21. A semiconductor device comprising a metal phosphide deposited according to the method of claim 1.

22. A deposition assembly for depositing a layer comprising a metal phosphide on a substrate, the deposition assembly comprising: one or more reaction chambers constructed and arranged to hold a substrate; a precursor injector system constructed and arranged to provide the metal halide precursor and the second precursor into the reaction chamber in a vapor phase; wherein the deposition assembly includes a first precursor container constructed and arranged to contain and evaporate a metal halide precursor comprising metal atoms and halogen ligands; a second precursor container constructed and arranged to contain and vaporize a second precursor; and Therein, the assembly is constructed and arranged to provide a metal halide precursor and a second precursor to a reaction chamber via a precursor injector system to deposit a layer comprising a metal phosphide on a substrate.

23. The assembly of claim 22, wherein: The assembly also includes a temperature controller for controlling the temperature of the reaction chamber.

Images