Method of forming a structure comprising silicon nitride on titanium nitride and the structure formed

Abstract

A method of forming a structure including silicon nitride on a titanium nitride layer is disclosed. The method includes forming the titanium nitride layer and the silicon nitride layer in the same reaction chamber, for example, without a vacuum breaker, to mitigate oxidation of the titanium nitride layer that might otherwise occur.

Description

Technical Field

[0001] The present disclosure relates generally to thin film deposition methods and structures. More particularly, the present disclosure relates to methods of forming a silicon nitride capping layer on a titanium nitride film and structures containing such layers and films. Background Art

[0002] Titanium nitride films can be used as metal or conductive layers in a variety of applications. For example, titanium nitride films can be used as metal layers in metal oxide semiconductor (MOS) devices or structures that form part of such devices. It may be desirable to use titanium nitride films or layers in such structures, particularly in cases where the channel region of the MOS device comprises silicon germanium, because the titanium nitride layer has oxygen scavenging properties, which may be desirable for reducing the interfacial trapped charge density (Dit) across the band gap of such structures and / or reducing the equivalent oxide thickness (EOT). Titanium nitride layers can also be used as work function layers in MOS devices.

[0003] When exposed to an oxidizing environment such as a substrate transfer area or a front opening unified or universal wafer transfer box (FOUP) that may contain water vapor and / or oxygen, the titanium nitride film is easily oxidized to form titanium oxynitride. The titanium oxynitride film has a higher resistivity than the titanium nitride film and is therefore generally less ideal for a metal film for a MOS device. In addition, the oxygen scavenging properties of the titanium oxynitride film are reduced relative to the oxygen scavenging properties of the titanium nitride film.

[0004] In order to reduce the oxidation of titanium nitride films, efforts are made to reduce the exposure of substrates containing titanium nitride films to oxidizing environments before subsequent processing. The use of nitrogen to the transfer module of the processing tool, the substrate loading / unloading area of ​​the sealing processing tool, and the use of nitrogen-purged FOUPs can be used to reduce the exposure of substrates containing titanium nitride films to oxidizing environments. However, such procedures are relatively expensive and require modified processing tools to provide adequate sealing. In addition, such techniques will still allow an undesirable amount of oxidation of the titanium nitride material before subsequent processing. Therefore, there is a need for an improved method for maintaining the desired properties of titanium nitride films while reducing any additional costs or complexity of substrate processing. Summary of the invention

[0005] Various embodiments of the present disclosure are directed to methods of mitigating undesirable oxidation of titanium nitride films. Although the manner in which various embodiments of the present disclosure address the shortcomings of prior methods is discussed in more detail below, in general, various embodiments of the present disclosure provide an in-situ method of capping a titanium nitride layer with a material that is less susceptible to oxidation and / or will mitigate oxidation of the titanium nitride film.

[0006] According to an exemplary embodiment of the present disclosure, a method of forming a structure includes providing a substrate in a reaction chamber, forming a layer containing titanium nitride on the substrate in the reaction chamber, and forming a layer containing silicon nitride on the layer containing titanium nitride in the reaction chamber. The step of forming the layer containing titanium nitride and the step of forming the layer containing silicon nitride are performed in the same reaction chamber-for example, without exposing the substrate to another intermediate environment (for example, a substrate transfer area of ​​a processing tool, etc.) or exposing the substrate to an intermediate vacuum breaker. The step of forming the layer containing silicon nitride may include a cyclic deposition step, such as atomic layer deposition. According to various aspects of these embodiments, the step of forming the layer containing silicon nitride can be self-limiting, that is, the growth of the silicon nitride layer can be substantially stopped after the silicon nitride layer reaches a certain thickness-for example, in some cases about 2 angstroms. According to further aspects, the thickness of the silicon nitride layer is greater than 0 angstroms and less than 5 angstroms. Because the titanium nitride and silicon nitride layers are deposited in the same reaction chamber, the deposition conditions (for example, pressure, temperature) can be substantially the same (for example, within 10%, 5%, 2%, 1% or 0.5%). The titanium nitride layer may be formed over a high dielectric constant material such as hafnium oxide and / or a work function layer such as titanium carbide, titanium aluminum carbide, etc. According to still further aspects of these embodiments, the step of forming a layer comprising titanium nitride and the step of forming a layer comprising silicon nitride may be repeated individually and / or collectively a number of times to form a laminate structure formed of deposited layers of titanium nitride and silicon nitride.

[0007] According to another embodiment of the present disclosure, a structure comprising a titanium nitride layer and a silicon nitride layer is formed according to the method disclosed herein. An exemplary structure may include, for example, a channel region (e.g., a silicon germanium channel region), a high dielectric constant layer (e.g., comprising a high dielectric constant material as described herein) above the channel region, a layer comprising a titanium nitride layer above the high dielectric constant layer, and a silicon nitride layer formed on the titanium nitride layer (e.g., in contact with the titanium nitride layer). BRIEF DESCRIPTION OF THE DRAWINGS

[0008] A more complete understanding of exemplary embodiments of the present disclosure may be derived by referring to the detailed description and claims when considered in conjunction with the following illustrative drawings.

[0009] Figure 1 A method according to at least one exemplary embodiment of the present disclosure is illustrated.

[0010] Figure 2 The structure according to at least one exemplary embodiment of the present disclosure is illustrated.

[0011] Figure 3 Another structure in accordance with at least one embodiment of the present disclosure is illustrated.

[0012] It should be understood that the elements in the figures are shown only for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be enlarged relative to other elements to help improve understanding of the embodiments of the present disclosure illustrated. DETAILED DESCRIPTION

[0013] The description of the exemplary embodiments provided below is merely exemplary and is intended for illustration purposes only; the following description is not intended to limit the scope of the present disclosure or the claims. Furthermore, the reference to multiple embodiments having the described features is not intended to exclude other embodiments having other features or other embodiments incorporating different combinations of the described features. Furthermore, the illustrations presented herein are not meant to be actual views of any particular material, structure, or device, but are merely idealized representations used to describe embodiments of the present disclosure.

[0014] The present disclosure generally relates to methods of forming structures and structures formed using the methods. As described in more detail below, the methods and structures described herein can be used to form, for example, MOS devices having high mobility channel materials (e.g., silicon germanium) that have relatively low interface trapped charge density and / or relatively low equivalent oxide thickness compared to structures and devices formed using other techniques. In addition, the exemplary methods can be used to form structures that include a titanium nitride layer and maintain relatively low resistance and / or relatively high oxygen scavenging properties of the titanium nitride layer.

[0015] As used herein, a layer comprising titanium nitride may comprise, consist essentially of, or consist of a titanium nitride material (with or without a dopant). A film consisting of titanium nitride (with or without a dopant) may contain acceptable amounts of impurities such as carbon and / or chlorine, which may originate from one or more precursors used to deposit the titanium nitride layer.

[0016] Similarly, a layer comprising silicon nitride may comprise, consist essentially of, or consist of a silicon nitride material. Films comprised of silicon nitride may contain acceptable amounts of impurities such as carbon, chlorine, and / or hydrogen that may originate from one or more precursors used to deposit the silicon nitride layer.

[0017] As used herein, the term substrate may refer to any underlying material or materials on which a material may be deposited. Exemplary substrates may be used to form devices, circuits, or structures. For example, a substrate may be or include a semiconductor material such as, but not limited to, silicon (Si), silicon oxide (e.g., SiO2), germanium (Ge), germanium oxide (e.g., GeO2), germanium tin (GeSn), silicon germanium (SiGe), silicon germanium tin (SiGeSn), silicon carbide (SiC), or a III-V semiconductor material such as, for example, gallium arsenide (GaAs), gallium phosphide (GaP), gallium nitride (GaN), and other materials such as titanium aluminum nitride (TiAlN), aluminum nitride (AlN), aluminum oxide (Al2O3), aluminum carbide (e.g., Al4C3), hafnium oxide (HfO2), titanium carbide (TiC), and titanium aluminum carbide (TiAlC). In some embodiments of the present disclosure, substrate 202 may include an engineered substrate in which a surface semiconductor layer is disposed above a body support with an intermediate buried oxide (BOX) disposed therebetween. The substrate may be patterned. The patterned substrate may include a substrate that may include semiconductor device structures formed in or on a surface of the substrate; for example, the patterned substrate may include partially fabricated semiconductor device structures, such as, for example, transistors and / or memory elements. In some embodiments, the substrate may contain a single crystal surface and / or one or more sub-surfaces, which may include non-single crystal surfaces, such as polycrystalline surfaces and / or amorphous surfaces. The single crystal surface may include, for example, one or more of silicon (Si), silicon germanium (SiGe), germanium tin (GeSn), or germanium (Ge). The polycrystalline or amorphous surface may include a dielectric material, such as an oxide, an oxynitride, a nitride, or a carbide, such as, for example, silicon oxide and silicon nitride. As a specific example and as described in more detail below, a substrate as described herein may include a silicon germanium (SiGe) (e.g., a channel) region and a high dielectric constant material (e.g., one or more of hafnium oxide (HfO2), lanthanum silicate (LaSiOx), aluminum silicate (e.g., Al2SiO5), niobium oxide (NbOx), zirconium oxide (e.g., ZrO2), hafnium silicate (HfSiO4), zirconium silicate (ZrSiO4), etc.); in addition or alternatively, the substrate may include a work function layer, such as titanium carbide (TiC), titanium aluminum carbide (TiAlC), titanium aluminum nitride (TiAlN), or tantalum nitride (TaN).

[0018] As used herein, SiGe refers to a silicon-germanium alloy SixGe1-x, where x is greater than 0 and less than 1. For example, x may be in the range of about 0.1 to about 0.9.

[0019] As used herein, the term "cyclic deposition" may refer to the sequential introduction of one or more precursors (reactants) into a reaction chamber to deposit a film over a substrate and includes deposition techniques such as atomic layer deposition and cyclic chemical vapor deposition.

[0020] As used herein, the term "atomic layer deposition (ALD)" may refer to a vapor deposition process in which a deposition cycle, such as a plurality of consecutive deposition cycles, is performed in a reaction chamber. Typically, during each cycle, a first precursor is chemically adsorbed to a deposition surface (e.g., a substrate surface or previously deposited underlying material, such as material from a previous ALD cycle), thereby forming a monolayer or sub-monolayer that is not susceptible to reaction with additional precursors (i.e., a self-limiting reaction). Thereafter, a reactant (e.g., another precursor or a reactive gas) may be subsequently introduced into the process chamber for converting the chemically adsorbed precursor to a desired material on the deposition surface. Typically, this reactant is capable of further reacting with the precursor. In addition, during each cycle, a purge step may also be utilized to remove excess precursor from the process chamber after converting the chemically adsorbed precursor and / or to remove excess reactant and / or reaction byproducts from the process chamber. As used herein, the term "atomic layer deposition" is also intended to include processes designated by related terms such as chemical vapor atomic layer deposition, atomic layer epitaxy (ALE), molecular beam epitaxy (MBE), gas source MBE or organometallic MBE and chemical beam epitaxy when performed using alternating pulses of a precursor composition, a reactive gas, and a purge gas (e.g., an inert carrier gas).

[0021] As used herein, the terms "layer", "film" and "thin film" may refer to any continuous or non-continuous structure and material formed by the methods disclosed herein. For example, a "layer", "film" and "thin film" may include 2D materials, nanolaminates, nanorods, nanotubes or nanoparticles or even partial or complete molecular layers or partial or complete atomic layers or clusters of atoms and / or molecules. A "layer", "film" and "thin film" may include a material or layer with pinholes, but still be at least partially continuous.

[0022] As used herein, SiN or silicon nitride refers to a compound containing silicon and nitrogen. x , wherein x varies, for example, from about 0.5 to about 2.0, wherein some Si-N bonds are formed. In some cases, x may vary from about 0.9 to about 1.7, from about 1.0 to about 1.5, or from about 1.2 to about 1.4. In some embodiments, silicon nitride is formed wherein Si has an oxidation state of +IV and the amount of nitride in the material may vary.

[0023] Similarly, TiN or titanium nitride refers to TiN x Compounds represented by wherein x varies from about 0.5 to about 2.0, as long as some Ti-N bonds are formed. In some cases, x may vary from about 0.5 to about 1.5, from about 0.8 to about 1.2, or from about 0.9 to about 1.1. In some embodiments, titanium nitride is formed wherein Ti has an oxidation state of +II, +III, or +IV and the amount of nitride in the material may vary.

[0024] Now turning to the attached figure, Figure 1 1 is a diagram illustrating a method 100 of forming a structure according to an exemplary embodiment of the present disclosure. The method 100 of forming a structure includes the steps of providing a substrate in a reaction chamber (step 102), forming a layer comprising titanium nitride on the substrate in the reaction chamber (step 104), and forming a layer comprising silicon nitride on the layer comprising titanium nitride in the reaction chamber (step 106). Figure 1 As shown in FIG. 1 , step 104 and / or step 106 may be repeated a certain number of times (illustrated as loops 112 and 114) before proceeding to the next step. In addition, the combination of steps 104 and 106 may be repeated a desired number of times (loop 110). As described in more detail below, steps 104 and 106 are performed in the same reaction chamber to mitigate any oxidation of the titanium nitride layer formed during step 104.

[0025] Step 102 includes providing a substrate in a reaction chamber. During step 102, the reaction chamber of the reactor may be brought to a desired deposition pressure and temperature for step 104. For example, after loading the substrate onto the reaction chamber, the temperature of the reaction chamber and / or the temperature of the susceptor within the reaction chamber may be from about 350° C. to about 650° C., or from about 400° C. to about 625° C., or from about 390° C. to about 450° C., or from about 450° C. to about 600° C., or from about 300° C. to about 400° C. The pressure within the reaction chamber may be in the range of from about 0.5 Torr to about 15 Torr, from about 1 Torr to about 10 Torr, or from about 2 Torr to about 5 Torr.

[0026] Next, a layer comprising titanium nitride is deposited over at least a portion of the substrate during step 104. The layer comprising titanium nitride can be formed using, for example, a cyclic or ALD deposition process using a titanium precursor such as, for example, titanium tetrachloride (TiCl4), titanium tetraiodide (TiI4), tetrakis(dimethylamido)titanium (TDMAT), or tetrakis(diethylamido)titanium (TDEAT) and a reactant gas such as a nitrogen-containing reactant gas.

[0027] In some embodiments of the present disclosure, step 104 includes exposing the substrate to the titanium precursor for a period of time between about 0.01 seconds and about 60 seconds, between about 0.05 seconds and about 10 seconds, or between about 0.1 seconds and about 5.0 seconds. During this stage of step 104, the flow rate of the titanium precursor and the carrier gas may be greater than 0 and less than 2000 sccm, or less than 800 sccm—for example, the flow rate of the titanium precursor may be in the range of about 1 to about 2000 sccm, about 5 to about 1500 sccm, or about 10 to about 1000 sccm, or about 325 sccm to about 800 sccm.

[0028] Step 104 may include a sub-step of purging the reaction chamber. For example, excess titanium precursor and reaction byproducts (if any) may be removed from the substrate surface and / or the reaction chamber, for example, by suction and / or pumping of an inert gas. In some embodiments of the present disclosure, the purging process may include a purge cycle in which the substrate surface is purged for a period of less than about 15.0 seconds, or less than about 10.0 seconds, or even less than about 5.0 seconds. Excess titanium precursor and any possible reaction byproducts may be removed by means of a vacuum generated by a suction system in fluid communication with the reaction chamber.

[0029] As described above, step 104 may also include introducing a nitrogen reactant gas into the reaction chamber, for example, after the above-mentioned purge sub-step. The nitrogen reactant gas may include at least one of nitrogen (N2), ammonia (NH3) hydrazine (N2H4), and a hydrazine derivative. In some embodiments of the present disclosure, the plasma may be generated by one or more of a direct plasma, a remote plasma, or a microwave plasma to form excited nitrogen-containing species. In certain embodiments of the present disclosure, the plasma may be remotely generated by a microwave source.

[0030] Step 104 may include an additional purge sub-step to remove, for example, excess nitrogen species and reaction byproducts (if any) from the substrate surface and / or the reaction chamber, for example, by suctioning and / or pumping an inert gas. In some embodiments of the present disclosure, the additional purge process may include a purge cycle in which the substrate surface is purged for a period of less than about 15.0 seconds, or less than about 10.0 seconds, or even less than about 5.0 seconds.

[0031] To further enhance the oxygen scavenging properties of the structure, the titanium nitride layer may be doped (e.g., with one or more of silicon, aluminum, tantalum, lanthanum, hafnium, and tungsten at a doping level of about 0.5 to about 20 atomic %, or about 2 to about 15 atomic %, or about 5 to about 10 atomic %). The doping may be achieved, for example, by co-flowing a suitable dopant precursor with the titanium precursor, reactant, or other precursor and / or by performing a separate ALD or cyclic deposition process to form a film comprising one or more of silicon, aluminum, tantalum, lanthanum, hafnium, and tungsten.

[0032] like Figure 1 As shown in , step 104 may be repeated a certain number of times (loop 112) before proceeding to step 106. For example, step 104 may be repeated 0, 5, 10, 50, or 200 times before proceeding to step 106.

[0033] Next, during step 106, a layer comprising silicon nitride is deposited over at least a portion of the titanium nitride layer formed during step 104. The silicon nitride layer can be formed using, for example, a (e.g., thermal) cycling or ALD deposition process using a silicon halide precursor such as, for example, SiCl4, SiBr4, or a chlorosilane precursor such as SiHCl3, SiH2Cl2, or a silane precursor such as SiH4, Si2H6, or Si3H8 and a nitrogen reactant gas.

[0034] As described above, steps 104 and 106 are performed in the same reaction chamber. Step 106 can be performed at the same pressure and / or the same temperature as step 104, such as any of the temperatures and pressures noted above in conjunction with step 104.

[0035] In some embodiments of the present disclosure, step 106 may include contacting the silicon precursor with the substrate for a period of time between about 0.01 seconds and about 60 seconds, between about 0.05 seconds and about 10 seconds, or between about 0.1 seconds and about 5.0 seconds. During this step, the flow rate of the silicon precursor may be greater than 0 and less than 2000 sccm, or less than 1000 sccm, or even less than 500 sccm. For example, the flow rate may be between about 100 and about 500 sccm.

[0036] Step 106 may include a sub-step of purging the reaction chamber. For example, excess silicon precursor and reaction byproducts (if any) may be removed from the substrate surface, for example, by suction and / or pumping of an inert gas. In some embodiments of the present disclosure, the purge process may include a purge cycle in which the substrate surface is purged for a period of less than about 15.0 seconds, or less than about 10.0 seconds, or even less than about 5.0 seconds. Excess silicon precursor and any possible reaction byproducts may be removed by means of a vacuum generated by a suction system in fluid communication with the reaction chamber.

[0037] As described above, step 106 may also include introducing a nitrogen reactant gas into the reaction chamber - for example, after the above-mentioned purge sub-step. The nitrogen reactant gas may include at least one of nitrogen (N2), ammonia (NH3) hydrazine (N2H4), a hydrazine derivative. The nitrogen reactant may be the same or different from the nitrogen reactant gas used during step 104. In some embodiments of the present disclosure, the plasma may be generated by one or more of a direct plasma, a remote plasma, or a microwave plasma to form excited nitrogen-containing species. In certain embodiments of the present disclosure, the plasma may be remotely generated by a microwave source.

[0038] Step 106 may include an additional purge sub-step to remove, for example, excess nitrogen species and reaction byproducts (if any) from the substrate surface and / or the reaction chamber, for example, by suctioning and / or pumping an inert gas. In some embodiments of the present disclosure, the purge process may include a purge cycle in which the substrate surface is purged for a period of less than about 15.0 seconds, or less than about 10.0 seconds, or even less than about 5.0 seconds.

[0039] Step 106 may be repeated a certain number of times (loop 114) before optionally repeating step 104 or ending the method (step 108). For example, step 106 may be repeated, for example, about 20 to about 40 times before proceeding to step 104 or 108.

[0040] According to various examples of the present disclosure, step 106 is self-limiting at a silicon nitride thickness of about 0.5 to about 2 angstroms or about 1 angstrom. It is observed that relatively thin silicon nitride films, for example, less than 1 or 2 angstroms, provide desirable film properties, namely, mitigating oxidation of the underlying titanium nitride layer without significantly increasing the resistivity of the compound film comprising silicon nitride and titanium nitride.

[0041] although Figure 1 Not shown, but the method according to the present disclosure may also include the steps of forming a passivation layer, forming an interface layer and / or forming a high dielectric material layer below the titanium nitride layer (for example, above the semiconductor layer / channel region). The method of forming an exemplary passivation or interface layer may include pretreatment with H2S or hydrazine. A more detailed description of an exemplary passivation process is disclosed in U.S. Patent No. 9,911,676, entitled "System and Method for Gas-Phase Passivation of a Semiconductor Surface", issued on March 6, 2018, the relevant contents of which are incorporated herein by reference to the extent that such contents do not conflict with the present disclosure. In addition or alternatively, a thin layer of silicon with a silicon oxide capping layer can be used as an interface / passivation layer between a semiconductor and a high dielectric constant material.

[0042] Additionally or alternatively, the method 100 of forming a structure may include a hydrogen plasma treatment after step 106 and before repeating or ending the method. The hydrogen plasma treatment process may include exposing the film deposited during step 106 (e.g., after one or more cycles) to excited hydrogen species formed using a direct or remote plasma device.

[0043] Now go to Figure 2 , which illustrates a structure 200 formed according to an exemplary method described herein. The structure 200 includes a first layer 202, a passivation and / or interface layer 204, a high dielectric constant material layer 206, a titanium nitride layer 208, and a silicon nitride layer 210.

[0044] The first layer 202 may be or form a portion of a substrate. For example, the first layer 202 includes a high mobility semiconductor material, such as SixGe1-x, where x is greater than 0 and less than 1, or about (e.g., greater than) 0 to about 0.25, or about 0.25 to about 0.5, or about 0.5 to about 0.75. The first layer 202 may be or form a portion of a channel region of, for example, a MOS device.

[0045] A passivation and / or interface layer 204 may be used to further improve EOT and / or reduce Dit. An exemplary passivation and / or interface layer includes a H2S or hydrazine pre-treated interface. Additionally or alternatively, the passivation and / or interface layer may include a thin layer (e.g., less than ~1 nm) of silicon and silicon oxide.

[0046] The titanium nitride layer 208 may be or include a titanium nitride layer formed using the techniques described above. In some embodiments of the present disclosure, the titanium nitride film formed by the exemplary method 100 may have a thickness of about 5 angstroms to about 50 angstroms, or about 10 angstroms to about 30 angstroms. In some embodiments, the titanium nitride film deposited according to some embodiments described herein may have a thickness greater than about 5 angstroms, or greater than about 10 angstroms, or greater than about 20 angstroms, or greater than about 50 angstroms. In some embodiments, a titanium nitride film, such as a titanium nitride film deposited according to some embodiments described herein, may have a thickness less than about 50 angstroms, or less than about 30 angstroms, or less than about 20 angstroms, or less than about 15 angstroms, or less than about 10 angstroms, or even less than about 5 angstroms. As a specific example, the thickness of the titanium nitride film is about 20 angstroms.

[0047] Silicon nitride layer 210 can be formed using techniques such as described herein. In some embodiments of the present disclosure, silicon nitride films formed by exemplary process 100 can have a thickness of greater than 0 angstroms to about 10 angstroms, to about 5 angstroms, to about 2 angstroms, or to about 1 angstrom.

[0048] Figure 3 Another structure that may be formed at least in part using the techniques described herein is illustrated. Structure 300 includes a first layer or substrate 302 , a metal carbide layer 304 , and a TiN / SiN laminate 306 including one or more TiN layers 308 , 312 and one or more SiN layers 310 , 314 .

[0049] The substrate 302 may include any substrate material described herein. For example, the substrate 302 may include a semiconductor layer, a passivation and / or interface layer, and a high dielectric constant material layer as described above.

[0050] The metal carbide layer 304 may be or include, for example, titanium carbide or titanium aluminum carbide. The thickness of the metal carbide layer 304 may vary depending on the application. For example, the metal carbide layer 304 may be about 1.0 to about 30, or about 2.0 to about 20, or about 5.0 to about 15 thick. However, the present disclosure is not limited to such number of layers or layer thicknesses, unless otherwise indicated. The metal carbide layer 304 may be, for example, a work function layer of a MOS device.

[0051] The laminate structure 306 includes at least one titanium nitride layer 308 and at least one silicon nitride layer 314. The laminate structure 306 may include a titanium nitride layer 308 at the bottom of the structure and a silicon nitride layer 314 at the top of the structure to prevent or mitigate oxidation of one or more titanium nitride layers. Each titanium nitride layer 308, 312 and each silicon nitride layer 310, 314 may be formed using the techniques described herein and may preferably be formed at a relatively low temperature, for example, in the range of about 390°C to about 500°C.

[0052] Although exemplary embodiments of the present disclosure are described herein, it should be understood that the present disclosure is not limited thereto. Various modifications, changes and enhancements may be made to the devices, components and systems described herein without departing from the spirit and scope of the present disclosure.

[0053] Unless otherwise stated, the subject matter of the present disclosure includes all novel and nonobvious combinations and sub-combinations of the various systems, components and configurations, and other features, functions, acts, and / or properties disclosed herein, and any and all equivalents thereof.

Claims

1. A method for forming a structure comprising a silicon nitride layer, the method comprising the steps of: providing a substrate in a reaction chamber, the substrate comprising a high dielectric constant material; depositing a layer comprising titanium nitride in the reaction chamber, the layer comprising titanium nitride overlying and contacting the high dielectric constant material, when the reaction chamber is at a temperature within a temperature range; Repeating the step of depositing a layer comprising titanium nitride a plurality of times, wherein the layer comprising titanium nitride is greater than 5 angstroms thick; and depositing a layer comprising silicon nitride in the reaction chamber with the reaction chamber at approximately the temperature, the layer comprising silicon nitride being overlying and in contact with the layer comprising titanium nitride, wherein the step of depositing the layer comprising silicon nitride is repeated and self-limited to a thickness of less than 2 angstroms; and Wherein, the step of depositing a layer comprising titanium nitride and the step of depositing a layer comprising silicon nitride are performed in the reaction chamber.

2. The method according to claim 1, further comprising hydrogen treatment. 3 . The method according to claim 2 , wherein the hydrogen treatment is performed after the step of depositing the layer comprising silicon nitride and after repeatedly depositing the layer comprising titanium nitride.

4. The method of claim 1, wherein the temperature during the step of depositing the layer comprising titanium nitride is between 350°C and 650°C.

5. The method of claim 4, wherein the temperature during the step of depositing the layer comprising silicon nitride is between 350°C and 650°C. 6 . The method of claim 1 , wherein the substrate further comprises one or more of an interface layer and a passivation layer in contact with the high dielectric constant material layer.

7. The method of claim 1, further comprising forming a passivation layer using one or more of H2S and hydrazine. 8 . The method of claim 1 , wherein the substrate further comprises an interface layer comprising a silicon layer below the high dielectric constant material layer. 9 . The method of claim 1 , wherein the step of depositing a layer comprising titanium nitride and the step of depositing a layer comprising silicon nitride are repeated to form a laminate.

10. The method of claim 1, wherein the substrate comprises a channel region comprising silicon germanium. 11 . The method according to claim 1 , further comprising the step of forming a passivation layer between the silicon germanium channel region and the high dielectric constant material.

12. The method of claim 1, wherein the titanium nitride layer further comprises a dopant selected from the group consisting of aluminum, tantalum, lanthanum, hafnium, and tungsten. 13 . The method according to claim 1 , further comprising forming a laminate structure by repeating the steps of depositing the layer containing titanium nitride and depositing the layer containing silicon nitride, wherein the laminate structure is covered with the layer containing silicon nitride.

14. A structure formed according to the method of claim 1.

15. The structure of claim 14, comprising: A channel region comprising silicon germanium.

16. The structure according to claim 15, comprising: The high dielectric constant material is above the channel region.

17. A method of forming a structure comprising a silicon nitride layer, the method comprising the steps of: Providing a substrate in a reaction chamber, the substrate comprising a passivation layer, an interface layer, and a high dielectric constant material layer; depositing a layer comprising titanium nitride in the reaction chamber, the layer comprising titanium nitride being overlying and in contact with the layer of high dielectric constant material using a cyclic deposition process, the cyclic deposition process comprising exposing a substrate to a titanium precursor and a nitrogen reactant; Repeating the cyclic deposition process until the layer comprising titanium nitride is greater than 5 angstroms thick; depositing a layer comprising silicon nitride in the reaction chamber using another cyclic deposition process, the layer comprising silicon nitride being overlying and in contact with the layer comprising titanium nitride; and Repeat another deposition cycle. wherein the step of depositing the layer comprising titanium nitride and the step of depositing the layer comprising silicon nitride are performed within the reaction chamber at a pressure within a pressure range within the reaction chamber without intervening vacuum breakers; and The step wherein a layer comprising silicon nitride is deposited is self-limited to a thickness in the range of 0.5 to 2 angstroms.

18. A method of forming a structure comprising a silicon nitride layer, the method comprising the steps of: providing a substrate in a reaction chamber, the substrate comprising a carbide metal layer; depositing a layer comprising titanium nitride overlying and in contact with the metal carbide layer; The step of depositing a layer comprising titanium nitride is repeated a plurality of times, wherein: The layer comprising titanium nitride is greater than 5 angstroms thick; depositing a layer comprising silicon nitride over and in contact with the layer comprising titanium nitride; and repeating the step of depositing a layer comprising silicon nitride, wherein the step of depositing a layer comprising silicon nitride is self-limited to a thickness of less than 2 angstroms, wherein the step of depositing a layer comprising titanium nitride and the step of depositing a layer comprising silicon nitride each include introducing a nitrogen reactant into the reaction chamber, the nitrogen reactant being the same for the step of depositing a layer comprising titanium nitride and the step of depositing a layer comprising silicon nitride; The step of depositing a layer comprising titanium nitride and the step of depositing a layer comprising silicon nitride are performed within the reaction chamber.

19. The method of claim 18, wherein the carbide metal layer comprises titanium aluminum carbide.

20. The method according to claim 18, wherein: The step of depositing a layer comprising silicon nitride comprises exposing the substrate to a silicon halide precursor or a chlorosilane precursor and a nitrogen reactant.

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