Method of forming metal silicide

Abstract

A method for forming a transition metal silicide is disclosed. An exemplary method comprises the step of selectively forming a transition metal silicide on a first surface relative to a second surface. The step of forming the transition metal silicide may include a catalyst-providing step. Additionally or alternatively, the exemplary method may include a cleaning and / or surface treatment step prior to the step of forming the transition metal silicide. The method described herein may be particularly useful for forming a structure suitable for an nmos device.

Description

Technology Field

[0001] The present disclosure relates to a method and apparatus for manufacturing an electronic device. More specifically, the present disclosure relates to a method for forming a silicide on a substrate. Background Technology

[0002] Metal silicides are frequently used to form contacts for the source and drain regions of field-effect transistor (FET) devices, such as metal-oxide-semiconductor FETs (MOSFETs). For n-channel MOSFETs (NMOS) devices, silicides are typically formed by depositing titanium on Si:P or SiGe:B surfaces using a plasma-enhanced titanium deposition process. For complementary metal-oxide-semiconductor (CMOS) devices, NiPt may be deposited on the source and / or drain regions of p-channel metal-oxide-semiconductor (PMOS) devices, and a plasma-enhanced titanium deposition process may be used to deposit titanium on both PMOS and NMOS structures.

[0003] While using a plasma-enhanced titanium deposition process to deposit titanium may be suitable for various applications, such processes generally suffer from poor adaptability, lack of selectivity, and require specialized hardware. Consequently, these processes can be relatively time-consuming and costly.

[0004] Therefore, an improved method for forming metal silicides is required. An improved structure formed using this method is also required.

[0005] All discussions, including the problems and solutions presented in this section, are incorporated into this disclosure solely for the purpose of providing context for the present disclosure. Such discussions should not be construed as an acknowledgment that any or all of the information was known at the time the present invention was made or otherwise constitutes prior art.

[0006] The content of the present invention may be introduced in a simplified form of the selection of concepts, which may be explained in more detail below. The content of the present invention is not intended to necessarily distinguish the main 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 a method for forming silicides on a substrate. As described in more detail below, the method described herein may be used during the manufacture of electronic devices. Such a method may reduce the complexity and / or cost of device manufacturing, provide a conductive layer with reduced contact resistance, provide a selective layer deposition technique, and / or enable filling vias or other depressions on the substrate surface in a relatively defect-free manner. For example, the method described herein may be used in the formation of memory, logic, other gate electrode devices, organic light-emitting diodes, liquid crystal displays, thin-film solar cells, other photovoltaic devices, etc.

[0008] According to examples of the present disclosure, a method for forming a structure such as a structure suitable for use as an NMOS structure is provided. An exemplary method comprises the steps of providing a substrate comprising a semiconductor surface within a reaction chamber of a reactor, and forming a transition metal silicide layer on the semiconductor surface using a cyclic deposition process. According to examples of the present disclosure, the cyclic deposition process comprises the steps of providing a pulse of a transition metal precursor to a reaction chamber, providing a pulse of a silicon precursor to a reaction chamber, and providing a catalyst to a reaction chamber. In some cases, the step of providing the catalyst may include a soak process. According to a specific example, one cycle of the cyclic deposition process comprises the steps of performing in order A) providing a pulse of a transition metal precursor to a reaction chamber, B) providing a pulse of a silicon precursor to a reaction chamber, and C) providing a catalyst to a reaction chamber. The transition metal may include Nb, Ti, Mo, Hf, Pd, Mo, Ni, V, and / or Pt. The catalyst may comprise one or more Group 13 elements (e.g., Al) and / or La, Mg, Sc, or Y. An exemplary method may further comprise a degassing step prior to the step of forming a transition metal silicide layer. Additionally or alternatively, an exemplary method may comprise a cleaning step prior to the step of forming a transition metal silicide layer. According to further examples, the method may be performed in a reactor system comprising a plurality of process modules. For example, cleaning may be performed within a first process module of the reactor system, and the step of forming a transition metal silicide layer may be performed within a second module of the reactor system. Degassing and / or other steps may be performed in other process modules. An exemplary method may comprise the step of forming a cap layer and / or the step of depositing a bulk metal layer.

[0009] According to additional examples of the present disclosure, a method for forming a structure (e.g., suitable for use as an NMOS structure) comprises providing a substrate comprising a semiconductor surface into a reaction chamber of a reactor, performing plasma treatment, and forming a transition metal silicide layer on the semiconductor surface using a cyclic deposition process. The step of forming the transition metal silicide layer may include providing a pulse of a transition metal precursor to the reaction chamber, providing a pulse of a silicon precursor to the reaction chamber, and optionally providing a catalyst to the reaction chamber (e.g., in order). The method according to these embodiments includes plasma treatment and does not necessarily include, but may include, the step of providing a catalyst.

[0010] According to other additional examples, a system is provided. An exemplary system is configured to perform a method as described herein. For example, the system may include a cleaning module, a deposition module, and a controller configured to enable the system to move a substrate from the cleaning module to the deposition module and perform a method as described herein.

[0011] These and other embodiments will be easily and clearly understood by those skilled in the art from the following detailed description of specific embodiments with reference to the accompanying drawings. The present invention is not limited to any specific embodiments disclosed. Brief explanation of the drawing

[0012] A more complete understanding of the embodiments of the present disclosure can be achieved by referring to the detailed description and claims in conjunction with the following exemplary drawings. FIG. 1 illustrates a method according to an exemplary embodiment of the present disclosure. FIG. 2 illustrates a structure according to an example of the present disclosure. FIG. 3 illustrates another structure according to an example of the present disclosure. FIG. 4 illustrates another method according to an exemplary embodiment of the present disclosure. FIG. 5 illustrates an exemplary reactor system according to an example of the present disclosure. FIG. 6 illustrates another exemplary reactor system according to the example of the present disclosure. It should be understood that the elements of the drawings are depicted in a simplified and clear manner and are not necessarily depicted in actual proportion. For example, to aid in understanding the embodiments illustrated in the present disclosure, the dimensions of some components in the drawings may be exaggerated compared to other components. Specific details for implementing the invention

[0013] The description of exemplary embodiments of the method, structure, and system provided below is merely illustrative and is for illustrative purposes only. The following description is not intended to limit the scope of the present disclosure or claims. Furthermore, citing multiple embodiments having the indicated features or steps is not intended to exclude other embodiments having additional features or steps or other embodiments including other combinations of the specified features or steps.

[0014] As described in more detail below, various embodiments of the present disclosure provide a method for forming a structure such as a structure suitable as an NMOS structure. For example, a metal silicide can be selectively formed on the surface of a substrate using an exemplary method. Additionally or alternatively, a metal silicide can be formed on a relatively clean surface (e.g., from which (e.g., natural) oxide films have been removed) using an exemplary method. The method described herein can be used to form a metal silicide to reduce the contact resistance of a layer containing a transition metal. Additionally or alternatively, a method for forming a transition metal silicide can be used with a relatively simple process and / or reduced equipment requirements. Furthermore, in at least some cases, the metal silicide can be formed at a relatively low temperature.

[0015] Metal silicides formed according to the method described herein may be particularly suitable for back-ends and intermediate-ends of lines processing electronic devices such as semiconductor devices. As a specific example, the method described herein may be used during the formation of logic devices and memory devices such as dynamic random access memory (DRAM) devices.

[0016] In the present disclosure, the gas may include a material that is a gas at normal temperature and pressure (NTP), a vaporized solid, and / or a vaporized liquid, and may consist of a single gas or a mixture of gases depending on the context.

[0017] The terms precursor and reactant may refer to molecules (compounds or molecules containing a single element) that participate in a chemical reaction to produce another compound. A precursor typically comprises a portion that is at least partially incorporated into the compound or element produced from the said chemical reaction. This final compound or element may be deposited on a substrate. A reactant may be an element or compound that is not incorporated to a significant extent into the final compound or element. In some cases, the term reactant may be used interchangeably with the term precursor.

[0018] As used herein, transition metal precursors comprise a gas or a substance that can be in a gaseous state, which can be represented by a chemical formula containing a transition metal. Oxygen-free transition metal precursors comprise a transition metal compound whose chemical formula does not contain oxygen.

[0019] As used herein, silicon precursors include substances that can be gaseous or in a gaseous state, which can be represented by a chemical formula containing silicon.

[0020] As used herein, the term substrate may refer to any underlying material(s) that may be used to form a device, circuit, or film, or upon which such may be formed. The substrate may comprise a bulk material 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 may comprise one or more layers placed on or below the bulk material. Additionally, the substrate may comprise various features, such as concave areas and protrusions, formed within or on at least a portion of the layers of the substrate. As an example, the substrate may comprise a semiconductor material. The semiconductor material may comprise or be used to form one or more of the source, drain, or channel regions of the device. The substrate may further comprise an interlayer dielectric (e.g., silicon oxide) and / or a high dielectric constant material layer placed on the semiconductor material. In this context, the high dielectric constant material or high dielectric constant material is a material having a dielectric constant greater than the dielectric constant of silicon dioxide.

[0021] As used herein, the structure may be a substrate as described herein or may include such a substrate. The structure may include a substrate and one or more layers disposed upon the substrate, for example, one or more layers formed by a method according to the present disclosure. The structure may include, for example, contacts or local interconnections within a MEOL process or may be used to form them. The structure may also be used to form layers of gate electrodes, buried power rails, and word lines or bit lines in logic applications.

[0022] As used herein, the term film and / or layer may refer to any continuous or discontinuous structure and material, such as a material deposited by the method disclosed herein. For example, the film and / or layer may comprise a two-dimensional material, a three-dimensional material, nanoparticles, a partial or whole molecular layer or a partial or whole atomic layer or an atomic and / or molecular cluster. The film or layer may be partially or wholly composed of a plurality of dispersed atoms embedded on the surface of a substrate and / or within the substrate, or embedded in a device fabricated on the substrate. The film or layer may comprise a material or layer having pinholes and / or isolated islands. The film or layer may be at least partially continuous. The film or layer may be patterned, for example, subdivided, and may constitute a plurality of semiconductor devices.

[0023] The term cyclic deposition process or cyclic deposition process may refer to the deposition of a layer on a substrate by sequentially introducing precursors (and / or reactants) into a reaction chamber, and includes processing techniques such as atomic layer deposition (ALD), cyclic chemical vapor deposition (cyclic CVD), and hybrid cyclic deposition processes comprising ALD components and cyclic CVD components. In some cases, the cyclic deposition process may include the step of continuously flowing one or more precursors, reactants, or inert gases, and the step of pulsed the precursors or reactants and something else.

[0024] As used herein, the term "purge" may refer to a procedure in which an inert or substantially inert gas is supplied to a reaction chamber between two pulses of gases capable of reacting with each other. For example, a purge using an inert gas, such as a noble gas, may be supplied between a precursor pulse and a reactant pulse to reduce gas-phase interactions that may occur between the precursor and the reactant. It should be understood that the purge may be applied temporally and / or spatially. For example, in the case of a temporal purge, the purge step may be used in the temporal sequence of, for example, supplying a precursor to the reaction chamber, supplying a purge gas to the reaction chamber, and supplying a reactant or other precursor to the reaction chamber, wherein the substrate on which the layer is deposited does not move. In the case of a spatial purge, the purge step may take the form of moving the substrate from a first position where the precursor is supplied (e.g., continuously) to a second position where the reactant or other precursor is supplied (e.g., continuously) through a purge gas curtain.

[0025] Additionally, in this disclosure, any two numeric values ​​of a variable may constitute an actionable range of the variable, and any indicated range may include or exclude endpoints. Additionally, any value of the indicated variable may refer to an exact value or an approximate value (whether indicated with the term "about"), may include equivalents, and may refer to an average value, median value, representative value, majority value, etc. For example, the term "about" may refer to + / - 20, 10, 5, 2, or 1 percent of the value. Also, in this disclosure, the terms "comprising," "including," "constituted by," and "having" independently refer to "typically or extensively including," "including," "essentially composed by," or "constituted by" in some embodiments.

[0026] In the present disclosure, any defined meaning does not necessarily exclude the general and conventional meaning in some embodiments.

[0027] Now, looking at the drawings, FIG. 1 illustrates a method (100) according to an embodiment of the present disclosure. The method (100) includes the steps of providing a substrate in a reaction chamber (step 102), forming a transition metal silicide layer (e.g., optionally) (step 104), optionally performing a degassing step (step 106), optionally performing a surface cleaning step (step 108), optionally forming a capping layer (step 110), and optionally (e.g., optionally) depositing a metal layer (step 112).

[0028] In step (102), a substrate is provided within a reaction chamber. The reaction chamber used in step (102) may be or may include a reaction chamber of a chemical vapor deposition reactor system configured to perform a cyclic deposition process. The reaction chamber may be a standalone reaction chamber or part of a cluster tool, such as a cluster tool described in more detail below. The reaction chamber may include a substrate heater for heating the substrate to the temperature specified herein. Additionally, or alternatively, the reaction chamber may include a rapid heat treatment device, such as a lamp, for heating the substrate.

[0029] The substrate provided during step (102) may include a first surface and a second surface. The first surface may include a first material, and the second surface may include a second material different from the first material. For example, the first material may be silicon, silicon germanium, doped silicon (e.g., Si:P), doped silicon germanium (e.g., SiGe:B), or their (e.g., natural) oxides, or may include them. The second material may include a dielectric material such as, for example, an oxide or a nitride. As an example, the second material may be an interlayer dielectric such as silicon oxide, silicon nitride, silicon carbonitride, silicon oxycarbide, or may include them.

[0030] FIG. 2 illustrates a portion or cross-section of a substrate (200) suitable for use as a substrate provided during step (102). The substrate (200) comprises a first surface (205) on a first material (204) and a second surface (209) on a second material (208). The first material (204) and the second material (208) may be as described above. The first surface (205) may be an oxide (206) (e.g., natural) on the first material or on it, or may comprise it. As shown in FIG. 2, a liner or barrier layer may not be present, and accordingly, the transition metal silicide layer and the subsequently formed metal layer may be in direct contact with the second material (208) as well as the first material (204). This allows for lower contact resistance compared to conventional processes requiring a barrier layer between the metal and, for example, an interlayer dielectric layer, and / or enables a relatively less complex manufacturing process.

[0031] Step (102) may include heating the substrate in a reaction chamber to a desired deposition temperature. In some embodiments of the present disclosure, step (102) includes heating the substrate to a temperature of less than 650°C and / or greater than 400°C. For example, in some embodiments of the present disclosure, the step of heating the substrate to a deposition temperature may include heating the substrate to a temperature of about 200°C to about 500°C, about 250°C to about 400°C, about 20°C to about 1000°C, about 400°C to about 650°C, or about 500°C to about 600°C (e.g., using a substrate heater).

[0032] In addition to controlling the substrate temperature, the pressure inside the reaction chamber may also be controlled. For example, in some embodiments of the present disclosure, the pressure inside the reaction chamber during step (102) may be less than 760 Torr or 0.2 Torr to 760 Torr, about 1 Torr to 100 Torr, or about 1 Torr to 10 Torr.

[0033] In step (104), a transition metal silicide layer is deposited (e.g., optionally) on the first surface (e.g., the first surface (205)) relative to the second surface (e.g., the second surface (209)). By depositing the metal silicide on the first surface (205), the silicide can be formed without consuming the first material (204).

[0034] According to an example of the present disclosure, and referring to FIG. 1, the step (104) of forming a transition metal silicide layer may include a cyclic deposition process comprising the steps of providing a pulse of a transition metal precursor (e.g., oxygen-free) to a reaction chamber, providing a pulse of a silicon precursor to a reaction chamber, and providing a catalyst to a reaction chamber. The steps of providing a pulse of the transition metal precursor, providing a pulse of the silicon precursor, and providing a catalyst may be repeated. According to examples of these embodiments, the cycle of the cyclic deposition process is

[0035] A) A step of providing a pulse of a transition metal precursor to a reaction chamber;

[0036] B) a step of providing a pulse of silicon precursor to a reaction chamber; and

[0037] C) Includes the step of performing the step of providing a catalyst to the reaction chamber in sequence.

[0038] Performing the steps in this order mitigates the formation of pollutants and promotes the formation of metal silicides.

[0039] In some embodiments, a transition metal precursor (e.g., oxygen-free) is provided as a single compound or a mixture of two or more compounds. In the mixture, other compound(s) in addition to the transition metal compound may be one or more inert compounds or elements, i.e., inert gases or may include them. In some embodiments, the transition metal precursor is provided as a composition. A composition suitable for use as a precursor may comprise a transition metal and an effective amount of one or more stabilizers and / or inert or carrier gases, e.g., argon, nitrogen, and / or hydrogen. The composition may be a solution or a gas in the NTP.

[0040] According to examples of the present disclosure, a transition metal compound or precursor comprises a transition atom and an organic (e.g., hydrocarbon) ligand. The transition metal atom may be one or more of Nb, Ti, Mo, Hf, Pd, Mo, Ni, V, and / or Pt, or may comprise them. In some embodiments, the transition metal precursor comprises a metal-organic compound comprising a transition metal. In such cases, the transition metal precursor may be referred to as a metal-organic transition metal precursor. In the above, a metal-organic transition metal precursor is intended to comprise a transition metal compound comprising a transition metal atom and a hydrocarbon ligand, wherein the transition metal atom is not directly bonded to a carbon atom. In some embodiments, the metal-organic transition metal precursor comprises one transition metal atom that is not directly bonded to a carbon atom. In some embodiments, the metal-organic transition metal precursor comprises two or more transition metal atoms, none of which are directly bonded to a carbon atom. In some embodiments, the metal-organic transition metal precursor comprises two or more metal atoms, wherein at least one metal atom is not directly bonded to a carbon atom.

[0041] In some embodiments, the transition metal precursor comprises an organometallic transition metal compound comprising a transition metal. As described herein, the organometallic transition metal precursor is intended to refer to a transition metal compound comprising a transition metal atom and an organic (e.g., hydrocarbon) ligand, wherein the transition metal atom is directly bonded to a carbon atom. In embodiments where the transition metal organometallic precursor comprises two or more metal atoms, one or more of the metal atoms (e.g., all) may be directly bonded to a carbon atom. In some embodiments, the transition metal organometallic precursor comprises only one or more transition metals, carbon, and hydrogen. That is, the transition metal organometallic precursor does not comprise oxygen, nitrogen, or other additional elements. In some embodiments, the transition metal organometallic precursor comprises at least two hydrocarbon ligands. In some embodiments, the transition metal organometallic precursor comprises at least three hydrocarbon ligands. In some embodiments, the transition metal organometallic precursor comprises four hydrocarbon ligands. In some embodiments, the transition metal organometallic precursor comprises one hydrocarbon ligand and one hydride ligand. In some embodiments, the transition metal organometallic precursor comprises one hydrocarbon ligand and two or more hydride ligands. In some embodiments, the transition metal organometallic precursor comprises two hydrocarbon ligands and two hydride ligands. The hydrocarbon ligands described herein may be, for example, C1-C10 hydrocarbons or may include them.

[0042] In some embodiments, the transition metal precursor comprises one or more cyclic portions. For example, the transition metal precursor may comprise one or more benzene rings. In some embodiments, the transition metal precursor comprises two benzene rings. One or both of the benzene rings may comprise hydrocarbon substituents (e.g., C1-C6). In some embodiments, each benzene ring of the transition metal precursor comprises an alkyl substituent. The alkyl substituent may be a methyl group, an ethyl group, or a linear or branched alkyl group comprising three, four, five, or six carbon atoms. For example, the alkyl substituent of the benzene ring may be an n-propyl group or an iso-propyl group. Additionally, the alkyl substituent may be a butyl, pentyl, or hexyl moiety in the n-, iso-, tert-, or sec- form.

[0043] In some embodiments, the transition metal precursor comprises a cyclopentadienyl (Cp) ligand. For example, the transition metal precursor may comprise MCp2Cl2 or MCp2H2, M(iPrCp)2Cl2, M(iPrCp)2H2, M(EtCp)2H2, or may be essentially composed of these, where M represents a transition metal.

[0044] In some embodiments, the transition metal precursor comprises a transition metal halogenated compound comprising one transition metal and one or more halogen atoms, or composed of these. The transition metal precursor may comprise one or more of the ligands mentioned above and one or more halogen atoms. Alternatively, the transition metal precursor compound may consist of a transition metal and one or more halogen atoms. In some embodiments, the transition metal precursor comprises a transition metal chloride compound, a transition metal iodide compound, or a transition metal bromide compound. As a non-limiting example, the transition metal halogenated precursor may comprise at least one of a transition metal chloride (MCl5), a transition metal hexachloride (MCl6), a transition metal hexafluoride (MF6), a transition metal triiodide (MI3), or a transition metal dibromide (MBr2), wherein M is a transition metal such as one or more of Nb, Ti, Mo, Hf, Pd, Ni, V, Cr, Zr, and / or Pt. In some embodiments, the transition metal halide precursor may comprise a transition metal chalcogenide, and in certain embodiments, the transition metal halide precursor may comprise an oxygen-free transition metal chalcogenide halide. Exemplary chalcogenides include sulfur, selenium, and tellurium. Other suitable metal precursors that may be used in addition to or instead of the transition metal precursor include Er and Yb having the same ligands / compounds as mentioned above.

[0045] As a specific example, the transition metal precursor may be or include a transition metal halide. Exemplary examples include TaCl5, NbCl5, MoCl5, MoO2Cl2, TiCl4, HfCl4, and / or VCl4.

[0046] The duration of providing pulses of the transition metal precursor to the reaction chamber during each cycle may be about 0.1 seconds to about 60 seconds, about 0.1 seconds to about 10 seconds, or about 0.5 seconds to about 5 seconds. The flow rate of the transition metal precursor to the reaction chamber may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or may be in the range of about 10 to 2000 sccm, about 10 to 1000 sccm, or about 10 to 500 sccm.

[0047] The silicon precursor is of the general formula R a SiX b or R c X d Si-SiR c X d A compound having or may include the same, wherein each X in the formula may be independently selected from H, halogen, or other ligand, and each R may be a C1-C12 organic group, a is 0, 1, 2, or 3, b is 4-a, c is 0, 1, or 2, and d is 3-c. R may be a hydrocarbon. a a is 2 or 3 or c In the case where is 2, each R can be selected independently. In some embodiments, each R is selected from alkyl and aryl. For clarity, X may represent different (e.g., independently selected) ligands. Thus, in some embodiments, the co-reactant may be a halogen-substituted silane, such as SiH2Br2, SiH2I2, or SiH2Cl2.

[0048] In some embodiments, X is hydrogen, a substituted or unsubstituted alkyl or aryl, or a halogen. In some embodiments, X is H. In some embodiments, X is an alkyl or aryl. In some embodiments, X is a C1 to C4 alkyl. In some embodiments, X is a substituted alkyl or aryl. In some embodiments, X is a substituted alkyl or aryl, wherein the substituent comprises silicon. In some embodiments, X is selected from the group consisting of H, Me, Et, nPr, iPr, nBu, tBu, M'Me3, M'Et3, M'Pr3, M'Bu3, Cl, Br, or I, wherein M' is Si.

[0049] In some embodiments, the silicon precursor is of the general formula R3Si x , R2SiX2, R s It may have iX3 or SiX4, where a, b, R, and X are as above. In some embodiments, the silicon atom does not contain four identical substituents. In some embodiments, the silicon precursor is not SiH4. In some embodiments, the silicon precursor is not SiH2Me2. In some embodiments, the silicon precursor is not SiH2Et2. In some embodiments, the silicon precursor is not Si2H2.

[0050] In some cases, exemplary silicon precursors may consist of silicon and hydrogen. For example, silicon precursors may be silanes, e.g., silane (SiH4), disilane (Si2H6), trisilane (Si3H8), tetrasilane (Si4H4). 10 ) or general empirical formula Si x H (2x+2) It may include a higher-order silane having. In some cases, the silicon precursor may be or include a halogen-substituted silane, where one or more H may be substituted with a halogen such as F, I, Cl, or Br.

[0051] In some cases, the silicon precursor is silanediamine N,N,N',N-tetraethyl(C8H 22It may include amino silanes such as N2Si), BTBAS (bis(tert-butylamino)silane), BDEAS (bis(diethylamino)silane), or TDMAS (tris(dimethylamino)silane), hexakis(ethylamino)disilane (Si2(NHC2H5)6).

[0052] According to additional examples of the present disclosure, the silicon precursor does not contain a compound containing oxygen. In some cases, the step (110) of providing the silicon precursor includes the step of providing another gas, such as a hydrogen-containing gas (e.g., H2, or NH3, etc.).

[0053] The duration of providing the silicon precursor pulse during each cycle may be about 0.1 seconds to about 60 seconds, about 0.1 seconds to about 10 seconds, or about 0.5 seconds to about 5 seconds. The flow rate of the silicon precursor into the reaction chamber may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or may be in the range of about 10 to 2000 sccm, about 10 to 1000 sccm, or about 10 to 500 sccm.

[0054] The catalyst provided during step (104) may include one or more Group 13 elements and / or one or more of La, Mg, Sc, or Y. For example, the catalyst may include one or more of Al, La, Mg, Sc, or Y. An exemplary catalyst includes a metal-organo or organometallic compound. As a specific example, the catalyst may include or contain one or more of trimethylaluminum (TMA), triethylaluminum (TEA), triisobutylaluminum (TiBA), triterbutylaluminum (TTBA), and / or other Al organic precursor(s).

[0055] The duration of providing the catalyst during each cycle may be about 0.1 seconds to about 60 seconds, about 0.1 seconds to about 10 seconds, or about 0.5 seconds to about 5 seconds. The flow rate of the catalyst into the reaction chamber may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or may be in the range of about 10 to 2000 sccm, about 10 to 1000 sccm, or about 10 to 500 sccm.

[0056] Step (104) may include a short period of supplying catalyst to the reaction chamber with the exhaust valve open during a flush period (FP) for flushing the reaction chamber with catalyst. In some cases, the flush period (FP) may be omitted. If the reaction chamber is configured and arranged to accommodate a single substrate, the flush period (FP) may be, for example, 1 to 60 seconds or 2 to 30 seconds.

[0057] According to an example of the present disclosure, the step of providing the catalyst includes an immersion process, and the catalyst is supplied to the reaction chamber without being removed by a removal pump, or with the removal rate reduced during the loading period (LP) by closing the removal reaction chamber valve. This causes the pressure of the catalyst to accumulate within the reaction chamber. This pressure accumulation may be terminated when the pressure within the reaction chamber reaches a desired value. Alternatively, there may be a pressure relief valve that opens when the pressure within the reaction chamber increases above a predetermined maximum value, thereby terminating the pressure loading period (LP).

[0058] Subsequently, the catalyst may be maintained in a stationary state within the reaction chamber during the immersion period (SP) without providing or removing any catalyst. This may be accomplished by closing the reactor chamber valve. If the reaction chamber is configured and arranged to accommodate a single substrate, the loading period (LP) may be 1 to 3000 seconds, 3 to 1000 seconds, or 5 to 500 seconds; and the immersion period (SP) may be 10 to 9000 seconds, 50 to 5000 seconds, or 100 to 1000 seconds. The catalyst period may include the flush period (FP), the loading period (LP), and / or the immersion period (SP). In some cases, the flow rate of gas from the reaction chamber to the vacuum source during the immersion period is less than the flow rate of gas from the reaction chamber to the vacuum source while forming the transition metal silicide layer. During the entire catalyst period, the catalyst may react with the surface of the substrate.

[0059] The transition metal and / or silicon precursor and / or catalyst may be purged from the reaction chamber, for example, after each pulse and / or at the completion of step (104) and / or before and / or after each cycle. As previously described, purging may be applied temporally or spatially, or both. The purging time may be, for example, 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 or about 7 seconds. The flow rate of the purged gas into the reaction chamber may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or in the range of about 10 to 2000 sccm, about 10 to 1000 sccm, or about 10 to 500 sccm.

[0060] FIG. 3 illustrates a structure (300) after step (104), wherein a transition metal silicide layer (302) is formed within a gap (e.g., optionally). The structure (300) may be used to form an NMOS structure or may include it. As illustrated, the transition metal silicide layer (302) is formed on the first surface (205) (e.g., optionally) compared to the second surface (209). In this context, being formed optionally means that a greater amount of transition metal silicide is deposited on the first surface (205) compared to the second surface (209). In some embodiments of the present disclosure, process selectivity may be expressed as the ratio of the amount of material deposited on the first surface (e.g., layer thickness) to the sum of the amounts of material formed on the first surface and the second surface (e.g., layer thickness). For example, if 10 nm of transition metal silicide is deposited on the first surface (205) and 1 nm of transition metal silicide is deposited on the second surface (209), the selectivity of the corresponding selective deposition process is considered to be 91%. In some embodiments, the selectivity of the method disclosed herein is greater than 50%, greater than 75%, greater than 80%, greater than 90%, greater than 95%, greater than 97.5%, greater than 98%, greater than 99%, or even about 100%.

[0061] The transition metal silicide layer (302) may comprise, essentially consist of, or be composed of transition metal silicide. The layer composed of transition metal silicide may contain, in acceptable amounts, impurities such as carbon, chlorine or other halogens, and / or hydrogen, which may originate from one or more precursors used to deposit the transition metal silicide layer. As previously described, the transition metal may be or may comprise one or more transition metals selected from the group consisting of Nb, Ti, Mo, Hf, Pd, Mo, Ni, V, Cr, Zr, and / or Pt. As a specific example, the transition metal may be or may comprise Nb and / or Ti. As previously described, although described in the context of transition metals, in some cases, other metals such as Er and / or Yb may be used.

[0062] The thickness of the transition metal silicide layer (302) may be, for example, about 1 to about 40 nm or about 2 to about 10 nm. The transition metal silicide layer (302) may include a transition metal and silicon, or be essentially composed of them, or be composed of them.

[0063] In some cases, the method (100) may include the step (110) of forming a capping layer (304). In the step (110), the capping layer (304) illustrated in FIG. 3 may be formed (e.g., directly) on the transition metal silicide layer (302). The capping layer (304) may be, for example, a transition metal nitride or a transition metal layer, such as a titanium nitride layer, a molybdenum nitride layer, or a titanium layer, or may comprise such a layer.

[0064] The capping layer (304) can be formed using a deposition process (e.g., optional and / or cyclic) by providing a metal (e.g., transition metal) precursor and a nitrogen reactant to a reaction chamber. The metal precursor may be any transition metal precursor as described herein or may include such a. The flow rate and pulse time of the transition metal precursor may be as described above.

[0065] The nitrogen reactant may be at least one of, for example, ammonia (NH3), hydrazine (N2H4), triazane (N3H5), alkyl-substituted hydrazine or triazine, e.g., tert-butylhydrazine (C4H9N2H3), methylhydrazine (CH3NHNH2), dimethylhydrazine ((CH3)2N2H2), or nitrogen plasma, and may include the same, wherein the nitrogen plasma comprises atomic nitrogen, nitrogen radicals and / or excited nitrogen species.

[0066] The duration of the step of providing the nitrogen reactant to the reaction chamber may be about 0.1 seconds to about 60 seconds, about 0.1 seconds to about 10 seconds, or about 0.5 seconds to about 5 seconds. The flow rate of the nitrogen reactant to the reaction chamber may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or may be in the range of about 10 to 2000 sccm, about 10 to 1000 sccm, or about 10 to 500 sccm.

[0067] The thickness of the capping layer (304) may be about 1 to about 20 nm or about 2 to about 10 nm. The capping layer (304) may contain about 10 to about 90 atomic percent or about 20 to about 70 atomic percent of metal and / or about 30 to about 60 atomic percent of nitrogen. Alternatively, the capping layer (304) may contain about 100 atomic percent of metal.

[0068] According to a further example of the present disclosure, the method (100) includes the step (112) of depositing a (e.g., bulk) metal layer. The step (112) may be added to or replace the step (110).

[0069] In step (112), a transition metal such as molybdenum may be optionally deposited (e.g., directly) on the capping layer (304) or the transition metal silicide layer (302).

[0070] Step (112) may include a deposition process (e.g., circulating) comprising providing a metal (e.g., molybdenum) precursor and a reactant to a reaction chamber. In the method according to the present disclosure, the reactant may be in contact with a substrate comprising a chemically adsorbed metal (e.g., molybdenum) precursor. The conversion of the metal precursor to the metal may occur on the surface of the substrate. In some embodiments, the conversion may occur at least partially in a gaseous state.

[0071] The metal precursor, metal precursor flow rate, and metal precursor duration in step (112) may be as described above in relation to step (104). Similarly, the internal temperature and pressure of the reaction chamber may be as described above in relation to step (104).

[0072] Exemplary reactants suitable for use in step (112) include reducing agents. Exemplary reducing agents include foaming gas (H2+ N2), ammonia (NH3), hydrazine (N2H4), alkyl-hydrazine (e.g., tert-butyl hydrazine (C4H4)). 12It comprises one or more of (e.g., C1-C4) alcohols, (e.g., C1-C4) aldehydes, (e.g., C1-C4) carboxylic acids, (e.g., B1-B12) boranes or amines. As a specific example, the first reactant may be at least one of hydrogen (H2), silane (SiH4), disilane (Si2H6), trisilane (Si3H8), germane (GeH4), digermane (Ge2H6), borane (BH3), or diborane (B2H6).

[0073] The flow rate of the reactant supplied to the reaction chamber may be greater than 0 and less than 30 slm, less than 15 slm, less than 10 slm, less than 5 slm, less than 1 slm, or even less than 0.1 slm. For example, the flow rate may be about 0.1 to 30 slm, about 5 to 15 slm, or 10 slm or more. For a cyclic deposition process, the reactant may be pulsed for a duration of, for example, about 0.01 seconds to about 180 seconds, about 0.05 seconds to about 60 seconds, or about 0.1 seconds to about 30 seconds. In some embodiments, the metal precursor may be pulsed more than once, for example, two, three, or four times, before the reactant is pulsed to the reaction chamber. Similarly, there may be more than one, for example, two, three, or four, reactant pulses before the metal precursor is pulsed (i.e., provided) to the reaction chamber.

[0074] In some cases, purging may be used to remove any excess reactant and / or reaction byproduct from the reaction chamber, for example, after the reactant pulse and / or at the completion of the deposition step. Purging may be performed as described above.

[0075] As illustrated in FIGS. 1 and 3, in the step (112) of depositing metal, a metal layer (306) is formed (e.g., optionally) on the transition metal silicide layer (302) and / or capping layer (304). The step (112) may be performed in the same reaction chamber as the step (104 and / or 110).

[0076] The metal (e.g., the metal layer (306)) may be at least partially in elemental form. Thus, the oxidation number of the metal may be 0. Thus, the metal layer (306) may contain, or essentially consist of, a metal, e.g., molybdenum.

[0077] In some embodiments, the metal layer (e.g., metal layer 306) comprises, for example, about 60 to about 99 atomic percent (atomic %) of metal, or about 75 to about 99 atomic percent of metal, or about 75 to about 95 atomic percent of metal, or about 80 to about 95 atomic percent of metal. The metal layer deposited by the method according to the present disclosure may comprise, for example, about 80 atomic percent, about 83 atomic percent, about 85 atomic percent, about 87 atomic percent, about 90 atomic percent, about 95 atomic percent, about 97 atomic percent, or about 99 atomic percent of metal. The metal layer may contain an acceptable amount of impurities such as carbon, chlorine or other halogens, and / or hydrogen, which may originate from one or more precursors used to deposit the metal layer.

[0078] In some embodiments, the metal layer may contain less than about 20 atomic percent, less than about 15 atomic percent, less than about 10 atomic percent, less than about 8 atomic percent, less than about 6 atomic percent, less than about 5 atomic percent, less than about 4.5 atomic percent, or less than about 3 atomic percent of carbon. The thickness of the metal layer (306) may be about 1 to about 40 nm or about 2 to about 10 nm.

[0079] As described above, the method (100) may include a step (106) of performing degassing (106). The step (106) may be performed prior to the step (104) of forming a transition metal silicide layer. According to an example of the present disclosure, the degassing step (106) includes heating the substrate to a temperature of about 200°C to about 600°C, or about 300°C to about 500°C, or about 350°C to about 450°C. In the step (106), the pressure in the chamber may be less than 760 Torr, or about 0.1 to 50 Torr, or about 0.5 to 5 Torr. The duration of the step (106) may be about 1 to 30 minutes or about 5 to 15 minutes.

[0080] The method (100) may additionally or alternatively include a cleaning step (108) prior to the step (104) of forming a transition metal silicide layer. The step (108) may be performed within a reaction chamber or within another reaction chamber, for example, within the same system module. The cleaning step (108) may be used to remove (e.g., natural) oxides from a surface, for example, from a surface (205). In the step (108), active species formed using a fluorine-containing gas and active species formed using a hydrogen-containing gas or an NH3-containing gas are formed within or provided to the reaction chamber to form a cleaned surface. According to the examples described herein, the cleaned surface produces a metal silicide of higher quality (e.g., oxygen reduction at the interface) compared to a metal silicide formed using HF as an etchant, for example.

[0081] According to an example of the present disclosure, active species formed using a fluorine-containing gas and active species formed using a hydrogen-containing gas or an NH3-containing gas to form a cleaned surface are formed using an indirect or remote plasma device. The power used to form the plasma may be about 10 to about 1000 W or about 20 to about 200 W for a substrate with a diameter of 300 mm. The plasma operation duration may be about 1 to about 60 seconds or about 2 to about 10 seconds.

[0082] The fluorine-containing gas may be, for example, one or more of NF3, XeF3, or F2, or may include these. The flow rate of the fluorine-containing gas supplied to a remote or indirect plasma device may be about 1 to about 1000 or about 2 to about 100 sccm.

[0083] The hydrogen-containing gas may be one or more of NH3, N2 / H2 (e.g., 10 to 90 volume% H2), hydrazine, substituted hydrazine and / or triazine as described herein, or may include the same. The flow rate of the hydrogen-containing gas supplied to a remote or indirect plasma device may be about 1 to about 1000 or about 10 to about 200 sccm.

[0084] Fluorine-containing gas and hydrogen-containing gas or NH3-containing gas may be supplied sequentially to a plasma device and / or supplied to a separate plasma device or supplied to different regions of the plasma device. The plasma device may include one or more dedicated regions or units that can be dedicated to forming each active species. Alternatively, the active species formed using the fluorine-containing gas and the active species formed using the hydrogen-containing gas may be formed using the same plasma unit or region.

[0085] Although not separately described, the method (100) may optionally include a step of heating the substrate after step (104, 110, or 112). The substrate may be heated to a temperature of about 550°C to about 700°C, or about 400°C to about 900°C.

[0086] In some embodiments, the method according to the present disclosure comprises a thermal deposition process. In thermal deposition, a chemical reaction is promoted by a temperature increase relative to the ambient temperature. Generally, the temperature increase provides energy for the formation of a metal silicide, a capping layer, and / or a metal in the absence of other external energy sources, such as plasma, radicals, or other forms of radiation. For example, one or more steps (e.g., all of steps 104, 110, and 112) may be thermal processes. In some embodiments, a cleaning step (e.g., step 108) comprises a step of forming a plasma to form an active species as described above.

[0087] FIG. 4 illustrates another method (400) according to an example of the present disclosure. The method (400) comprises the steps of providing a substrate in a reaction chamber (step 402), performing a surface treatment (step 404), forming a transition metal silicide layer (e.g., optionally) (step 406), optionally performing a degassing step (step 408), optionally performing a surface cleaning (step 410), optionally forming a capping layer (step 412), and optionally (e.g., optionally) depositing a metal layer (step 414). The method (400) is similar to the method (100) except that the surface method (400) includes a treatment step (404) and may not include a step of providing a catalyst in the step of forming the metal silicide.

[0088] Steps (402, 408, 410, 412, and 414) may be identical or similar to the corresponding steps (102, 106, 108, 110, and 112) described above.

[0089] In step (404), surface treatment is performed. According to an example of the present disclosure, the surface treatment step includes a plasma treatment step. In some cases, the treatment step is a thermal step. As an example, step (404) includes thermal treatment (e.g., using a hydrogen and / or nitrogen-containing gas (e.g., a gas containing N and / or H as described herein), H* / N* (remote) plasma treatment, and / or TiBA / TTBA immersion.

[0090] Step (406) may be identical or similar to the aforementioned step (104). However, step (406) does not need to include a step of providing a catalyst as described above. Step (406) may include a step of forming a transition metal silicide layer on a semiconductor surface using a cyclic deposition process comprising a step of providing a pulse of a transition metal precursor to a reaction chamber, a step of providing a pulse of a silicon precursor to a reaction chamber, and a step of optionally providing a catalyst to a reaction chamber. Each of these steps may be as described above in relation to step (104).

[0091] FIGS. 5 and 6 illustrate exemplary systems (500 and 600) according to examples of the present disclosure. Systems (500 and 600) may be used to perform various steps of a method as described herein (e.g., method 100 or 400).

[0092] Referring to FIG. 5, the system (500) includes a degassing module (502, 504), a cleaning module (506, 508), a deposition module (510 to 516), and a controller (518). The system (500) may also include one or more substrate transfer devices (520, 522) for transferring substrates between the various modules and one or more cooling stations (524, 526).

[0093] The degassing module (502, 504) may be configured to perform a degassing step. For example, the degassing module (502, 504) may be configured to perform step (106 or 408).

[0094] The cleaning module (506, 508) may be configured to perform surface cleaning and / or surface treatment. For example, the cleaning module (506, 508) may be configured to perform one or more of the steps (108, 410, and / or 404) as described herein.

[0095] The deposition modules (510 to 516) may be configured to form a transition metal silicide layer on a semiconductor surface and / or to deposit a metal layer placed on top of the transition metal silicide layer. For example, one or more modules (510 to 516) may be configured to form a transition metal silicide layer and / or one or more modules (510 to 516) may be configured to deposit a metal layer.

[0096] The controller (518) may be configured to enable the system (500) to move a substrate between various modules, for example, using a transfer device (520, 522), and to perform steps of the method as described herein. As a specific example, the controller (518) may be configured to enable the system to move a substrate from a cleaning module to a deposition module and to form a transition metal silicide layer on a semiconductor surface using a cyclic deposition process within the deposition module.

[0097] The cooling station (524, 526) can be used to cool the substrate before proceeding to the next step of the method or before unloading the substrate from the system (500).

[0098] The system (600) includes a degassing module (602, 604), a cleaning module (606, 608), a deposition module (610 to 616), and a controller (618). The system (600) may also include one or more substrate transfer devices (620, 622) for transferring substrates between various modules and one or more cooling stations (624, 626). The system (600) is similar to the system (500) except that the system (600) includes one or more deposition modules (612, 614) for depositing a cap or metal layer (e.g., for performing step (110 or 412)).

[0099] The controller (618) may be identical or similar to the controller (518) except that the controller (618) may be additionally configured to cause the system (600) to deposit a cap or metal layer as described herein. Other system configurations including a module for performing the steps described herein are also within the scope of the present disclosure.

[0100] The exemplary embodiments of the foregoing disclosure are merely examples of embodiments of the invention and do not limit the scope of the invention as defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to be within the scope of the invention. In addition to what is shown and described herein, various variations of the disclosure, such as alternative useful combinations of the described elements, may become apparent from the description to those skilled in the art. Such variations and embodiments are also intended to be within the scope of the appended claims.

Claims

Claim 1 A method for forming a structure comprises the steps of: providing a substrate including a semiconductor surface into a reaction chamber of a reactor; and forming a transition metal silicide layer on the semiconductor surface using a cyclic deposition process, wherein the cyclic deposition process comprises: A step of providing a pulse of a transition metal precursor to the above reaction chamber; The step of providing a pulse of a silicon precursor to the reaction chamber; and A method comprising the step of providing a catalyst to the reaction chamber. Claim 2 A method according to claim 1, wherein the cycle of the cyclic deposition process comprises the steps of: A) providing a pulse of the transition metal precursor to the reaction chamber; B) providing a pulse of the silicon precursor to the reaction chamber; and C) providing the catalyst to the reaction chamber in sequence. Claim 3 A method according to claim 1, wherein the silicon precursor comprises one or more of a silane or a halogen-substituted silane. Claim 4 A method according to claim 1, wherein the transition metal precursor comprises one or more transition metals selected from the group consisting of Nb, Ti, Mo, Hf, Pd, Mo, Ni, V, Cr, Zr, and / or Pt. Claim 5 The method of claim 1, wherein the catalyst comprises one or more Group 13 elements and / or one or more of La, Mg, Sc, or Y. Claim 6 A method according to claim 1, further comprising a degassing step prior to the step of forming the transition metal silicide layer. Claim 7 A method according to claim 1, further comprising a cleaning step prior to the step of forming the transition metal silicide layer. Claim 8 A method according to claim 7, wherein the washing step comprises the step of providing an active species formed using a fluorine-containing gas and an active species formed using a hydrogen-containing gas to the reaction chamber. Claim 9 A method according to claim 7, wherein the cleaning step is performed in a first process module of the reactor system, and the step of forming a transition metal silicide layer is performed in a second module of the reactor system. Claim 10 A method according to claim 1, further comprising the step of depositing a metal layer placed on the transition metal silicide layer. Claim 11 In claim 10, the method wherein the metal layer comprises a transition metal layer or a transition metal nitride layer. Claim 12 In claim 10, the method wherein the metal layer comprises molybdenum, titanium nitride, or titanium. Claim 13 A method according to claim 1, wherein the structure comprises an NMOS structure. Claim 14 A method according to claim 1, wherein the substrate includes a gap, and the transition metal silicide layer is formed within the gap. Claim 15 A method according to claim 1, wherein the semiconductor surface comprises one or more of Si:P or SiGe:B. Claim 16 A method according to claim 1, wherein the step of providing the catalyst includes an immersion process. Claim 17 In claim 16, the method wherein the flow rate of gas from the reaction chamber to the vacuum source during the immersion period is less than the flow rate of gas from the reaction chamber to the vacuum source during the step of forming a transition metal silicide layer. Claim 18 In claim 1, the method wherein the temperature of the substrate support is higher than 400℃ while forming the transition metal silicide layer. Claim 19 A method for forming a structure comprises the steps of: providing a substrate including a semiconductor surface into a reaction chamber of a reactor; performing plasma treatment; and forming a transition metal silicide layer on the semiconductor surface using a cyclic deposition process, wherein the cyclic deposition process A step of providing a pulse of a transition metal precursor to the above reaction chamber; The step of providing a pulse of a silicon precursor to the reaction chamber; and A method comprising the step of optionally providing a catalyst to the reaction chamber. Claim 20 As a system, it includes a cleaning module; a deposition module; and a controller, wherein the controller is The system moves the substrate from the cleaning module to the deposition module, and A system configured to perform the method of claim 1 within the deposition module.

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