Patent Publication Number: US-2022235463-A1

Title: SixNy AS A NUCLEATION LAYER FOR SiCxOy

Description:
CLAIM OF PRIORITY 
     This application claims the priority benefit to U.S. Patent Application Ser. No. 62/850,343, filed on 20 May 2019, and entitled “Si x N y  AS A NUCLEATION LAYER FOR SiC x O y ,” which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The subject matter disclosed herein relates to methods of substrate processing used in the semiconductor and allied industries. More specifically, the disclosed subject matter relates to methods of depositing a silicon nitride nucleation layer substantially concurrently over combinations of dielectric and metal layers to avoid a substantial nucleation delay in a subsequently-deposited silicon carbide layer. 
     BACKGROUND 
     Fabrication of semiconductor devices often involves depositions of layers of dielectric materials over metal materials. Examples of such dielectric layers include encapsulation layers for memory stacks, as well as various diffusion-barrier layers, and etch-stop layers. Silicon carbide (SiC) is one of type of dielectric material frequently used for such applications. Classes of SiC thin films include oxygen-doped silicon carbide, also known as silicon oxycarbide (SiCO or, more generally, SiC x O y  (nitrogen-doped silicon carbide, also known as silicon nitricarbide, oxygen-doped and nitrogen-doped silicon carbide, also known as silicon oxynitricarbide, and undoped silicon carbide. Silicon carbide is typically deposited by chemical vapor deposition (CVD) processes, such as by plasma-enhanced chemical vapor deposition (PECVD) or, in some cases, by atomic-layer deposition (ALD) processes. Each of these deposition techniques is known in the art. 
     A person of ordinary shill in the art understands that the deposition of SiC x O y , or other dielectric films deposited on metals such as tungsten (W) and cobalt (Co), is slightly thinner than a deposition of SiC x O y  on dielectric materials, such as SiN, which means there is a delay in the nucleation and growth of the SiC x O y  on metals. This can become problematic in features that contain multiple materials in feature, as the SiC x O y  thickness varies depending on the type of material that exists at that particular location. A variation in thickness can affect, for example, a sidewall profile of the feature, the material properties of the SiC x O y  film (e.g., hermiticity, pinholes, wet and dry etch thicknesses, etc.) and can cause problems with subsequent device-integration steps. Current strategies to overcome the nucleation delay issue include:
         (1) Surface treatment: Prior to deposition, the metal surface is treated using an H 2 -based plasma or diborane-gas annealing process step. The mechanism is thought to change properties of the metal surface and promote a subsequent dielectric-film deposition; and   (2) SiO 2  Deposition: A silicon dioxide (SiO 2 )-based initiation-layer is deposited to attempt to address the dielectric-growth nucleation-delay on metal surfaces (as described with reference to  FIG. 2 , below). The SiO 2 -based solution decreases the differential thickness issue but not completely enough for advanced semiconductor devices. Also, this technique may be less robust when one or more properties of the metal surface have been changed by, for example, different etching and/or cleaning processes during device integration steps. Further, the SiO 2  process may cause a metal-oxide layer to form on the underlying metal material.       

       FIG. 1  shows an example of a cross-sectional semiconductor structure  100  having a silicon oxycarbide layer deposited over a combination of a dielectric material  101 , a metal material  103 , and a semiconductor material  105 , in accordance with methods of the prior art. The cross-sectional semiconductor structure  100  may be, for example, a bitline as used in various types of non-volatile memory devices. The silicon oxycarbide may be used to form a low dielectric-constant (low-κ) spacer over the cross-sectional semiconductor structure  100 . However, for bitline applications as well as numerous other types of applications, the thickness of silicon oxycarbide (e.g., a spacer) over the various materials should have a substantially constant thickness. In this example, the dielectric material  101  may be silicon nitride (SIN), the metal material  103  may be tungsten (W), and the semiconductor material  105  may be silicon (Si). 
     With continuing reference to  FIG. 1 , the semiconductor structure  100  has a first silicon-oxycarbide layer  107  formed over the dielectric material  101 , where the first silicon oxycarbide layer  107  has a first thickness, t 1 ; a second silicon-oxycarbide layer  109  formed over the metal material  103  having a second thickness, t 2 ; and a third silicon-oxycarbide layer  111  formed over the semiconductor material  105  having a third thickness, t 3 . As shown in  FIG. 1 , the third thickness, t 3 , of the third-silicon oxycarbide layer  111  is approximately the same thickness as the first thickness, t 1 , of the first silicon-oxycarbide layer  107 . However, the second thickness, t 2 , of the second-silicon oxycarbide  109  is substantially thinner than either the first thickness t 1  or the third thickness t 3 . 
     One reason the second silicon-oxycarbide layer  109  is thinner is due to nucleation differences of the silicon oxycarbide deposited on the metal material  103 . The nucleation differences are due to a difference in availability of reaction sites for the silicon oxycarbide in comparison with the silicon-oxycarbide layers  107 ,  111  formed over the dielectric material  101  and the semiconductor material  105 , respectively. Another reason for the difference in thicknesses of the respective silicon-oxycarbide layers  107 ,  109 ,  111  may be due to different chemical contamination levels on the three materials  101 ,  103 ,  107 . Regardless of the cause, the non-uniformity on thickness of the silicon-oxycarbide layers can be detrimental to many types of semiconductor devices. In some cases, the non-uniformity of thicknesses may make the semiconductor device slower, unstable, or affect device performance in other ways. In some cases, the non-uniformity of thicknesses may make the semiconductor device completely unusable. 
       FIG. 2  shows a cross-sectional semiconductor structure  200  having a silicon dioxide (SiO 2 ) initiation-layer  213  to reduce a thickness difference between a thickness of silicon oxycarbide deposited over a dielectric material  201 , deposited over a metal material  203 , and deposited over a semiconductor material  205 , in accordance with methods of the prior art. In one embodiment, the SiO 2  initiation-layer  213  may be a conformally-deposited ALD layer. The cross-sectional semiconductor structure  200  may be similar to or the same as the cross-sectional semiconductor structure  100  of  FIG. 1 . In this example, the dielectric material  201  may be silicon nitride (SiN), the metal material  103  may be tungsten (W), and the semiconductor material  105  may be polysilicon. 
     The semiconductor structure  200  has a first silicon-oxycarbide layer  207  formed over the dielectric material  201 , where the first silicon-oxycarbide layer has a first thickness, t 1 ; a second silicon-oxycarbide layer  209  formed over the metal material  203  having second thickness, t 2 ; and a third silicon-oxycarbide layer  211  formed over the polysilicon material  205  having a third thickness, t 3 . The third thickness, t 3 , of the third silicon-oxycarbide layer  211  is approximately the same thickness as the first thickness, t 1 , of the first silicon-oxycarbide layer  207 . The second thickness, t 2 , of the second silicon-oxycarbide  209  is thinner than either the first thickness t 1  or the third thickness t 3 . However, unlike the second silicon-oxycarbide  109  of the semiconductor structure  100  of  FIG. 1 , the thickness of the second silicon-oxycarbide  209  of  FIG. 2  is much closer to the thicknesses of the other two silicon-oxycarbide layers  207 ,  211 . 
     Consequently, the SiO 2  initiation-layer  213  at least partially addresses the dielectric-growth nucleation-delay on metal surfaces as discussed above. However, the SiO 2  initiation-layer  213  solution may be less robust when one or more properties of the metal surface have been changed by different etching and/or cleaning processes experienced by the semiconductor structure  200  during, for example, device integration steps. Therefore, even though the difference in thickness (Δt) using the SiO 2  initiation-layer  213  has greatly reduced the differential thickness difference, many contemporaneous semiconductor devices today require a Δt of less than about 2 mm to about 3 nm. 
     The information described in this section is provided to offer the skilled artisan a context for the following disclosed subject matter and should not be considered as admitted prior art. 
     SUMMARY 
     In one exemplary embodiment, the disclosed subject matter describes a method to produce a substantially uniform, silicon-carbide layer over both of at least one dielectric material and at least one metal material substantially concurrently. The method includes forming a silicon-nitride layer, in the form of SixNy, over the at least one dielectric material and the at least one metal material, and forming the silicon-carbide layer, in the form of SiCxOy, over the silicon-nitride layer. 
     In an exemplary embodiment, the disclosed subject matter describes a method for forming a silicon-carbide layer. The method includes forming a silicon nitride initiation-layer, in the form of SixNy, substantially simultaneously over at least a dielectric material and a metal material. The silicon nitride initiation-layer is to serve as a growth-initiation layer. The silicon-carbide layer, in the form of SiCxOy, is formed over the silicon nitride initiation-layer. The formed silicon nitride initiation-layer is to substantially prevent a delay in a nucleation and growth of the silicon-carbide layer on the metal material in comparison with a nucleation and growth of the silicon-carbide layer on the dielectric material. 
     In an exemplary embodiment, the disclosed subject matter describes a method for forming a silicon-carbide layer. The method includes forming layers of at least one metal material and at least one dielectric material in a deposition chamber on a substrate, forming silicon nitride in the form of SixNy as an initiation-layer over the at least one metal material and the at least one dielectric material on the substrate, and subsequently forming at least one layer over the silicon nitride where the at least one layer includes materials selected from materials including silicon carbide, in the form of SixCy, silicon carbon nitride, in the form of SixCyNz, silicon oxycarbonitride, in the form of SiCxNyOz, and silicon oxycarbide, in the form of SixCyOz. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  shows a cross-sectional semiconductor structure having silicon oxycarbide deposited over a combination of a dielectric material, a metal material, and a semiconductor material, in accordance with methods of the prior art; 
         FIG. 2  shows a cross-sectional semiconductor structure having an silicon dioxide (SiO 2 ) initiation-layer to reduce a thickness difference between a thickness of silicon oxycarbide deposited over a dielectric material, deposited over a metal material, and deposited over a semiconductor material, in accordance with methods of the prior art; 
         FIG. 3  shows an example of a cross-sectional semiconductor structure having a silicon nitride (SiN) initiation-layer formed substantially simultaneously formed over a dielectric material, a metal material, and a polysilicon material, in accordance with the disclosed subject matter; 
         FIG. 4  shows an exemplary process flow to prepare the SiN initiation-layer for forming over various types of material; 
         FIG. 5  shows an example of a cross-sectional schematic diagram of a remote-plasma apparatus with a processing chamber that may be used with various embodiments disclosed herein; and 
         FIG. 6  shows a simplified block diagram of a machine in an example form of a computing system within which a set of instructions for causing the machine to perform any one or more of the methodologies and operations (e.g., process recipes) discussed herein may be executed. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosed subject matter will now be described in detail with reference to a few general and specific embodiments as illustrated in various ones of the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the disclosed subject matter. It will be apparent, however, to one skilled in the art, that the disclosed subject matter may be practiced without some or all of these specific details. In other instances, well-known process steps, fabrication techniques, or structures have not been described in detail so as not to obscure the disclosed subject matter. 
     Manufacture of semiconductor devices typically involves depositing one or more thin films on a substrate in an integrated-fabrication process. In some aspects of the integrated-fabrication process, various types of thin films can be deposited using atomic layer deposition (ALD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), or any other suitable deposition methods and techniques as described above. 
     PECVD processes may use in-situ plasma processing for the deposition of silicon carbide classes of thin films, where the plasma processing occurs directly adjacent to a substrate. However, it has been found that depositing high-quality silicon carbide classes of thin films can have several challenges. For example, such challenges can include providing silicon carbide classes of thin films with excellent step coverage, low dielectric-constants, high breakdown-voltages, low leakage-currents, low porosity, high hermeticity, high density, high hardness, and coverage over exposed metal surfaces without oxidizing the metal surfaces, among other factors. 
     The silicon-carbide films described herein may include both doped and undoped silicon carbide, such as doped and undoped versions of Si x C y , silicon carbon nitride (Si x C y N z ), silicon oxycarbonitride (SiC x N y O z ), and silicon oxycarbide (Si x C y O z ) of varying stoichiometries (the formulas indicate various elemental compositions, but the stoichiometry can vary). Hydrogen may optionally be present in any of the silicon-carbide films (e.g., Si x C y , Si x C y N z , SiC x N y O z , and Si x C y O z  films). 
     In various embodiments, for the deposition processes described herein, a plasma is formed directly in the process chamber or process-chamber compartment that houses the substrate. However, while this disclosure is not limited by any particular theory, the plasma conditions in typical PECVD processes may produce undesirable effect. For example, the PECVD process may provide direct plasma conditions that break the Si—N and/or Si—C bonds in the precursor molecules. Direct plasma conditions can include charged particle bombardment and high-energy ultraviolet radiation, which can result in damaging effects in the thin film. 
     One such film-damaging effect resulting from direct plasma conditions can include poor step coverage. The charged particles in direct plasma conditions can lead to highly reactive radicals with increased sticking coefficients. A deposited silicon carbide film may have silicon, carbon, oxygen, and/or nitrogen bonds that are “dangling,” meaning that the silicon, carbon, and/or nitrogen atoms will have reactive, unpaired valence electrons. The increased sticking coefficients of precursor molecules can lead to deposition of silicon-carbide films with poor step coverage, as reactive precursor fragments may tend to stick to sidewalls of previously deposited films or layers. 
     Another film-damaging effect that may result from direct plasma conditions can include directionality in the deposition. This is due in part to the energy required to break up the precursor molecules can be at a low frequency, which creates a significant amount of ion bombardment at the surface. Directional deposition may further lead to depositions with poor step coverage. 
     Direct-plasma conditions in PECVD may also lead to increased production of silicon-hydrogen bonding (Si—H) in the silicon carbide film. Specifically, broken bonds of Si—C can be replaced with Si—H. This type of bonding can result in not only a reduced carbon content but may also result in films with poor electrical properties in some instances. For example, the presence of Si—H bonds can reduce breakdown voltages and increase leakage currents because the Si—H bonds provide a leakage path for electrons. 
     Consequently, due to the potential disadvantages of direct plasma types of processing, many of the techniques described herein rely on remote-plasma techniques, and especially, remote-plasma ALD techniques. In a remote-plasma technique in general, the plasma is formed remotely in a chamber that is different from the chamber that is housing the substrate. The plasma is then transferred to the chamber housing the substrate. This remote-plasma process is described in more detail with reference to  FIG. 5 , below. In various embodiments, the plasma is formed using a frequency in a range of between about 2.45 MHz to about 13.56 MHz, with power in a range of between about 2 kW to about 6 kW. In some embodiments pressure in the chamber is less than about 2 Torr, such as about 1.5 Torr or less. As is known to a person of ordinary skill in the art, lower pressures are often associated with higher deposition rates. However, in appropriate conditions and with appropriate safeguards, the disclosed subject matter can be applicable to direct-plasma techniques, described above, as well. 
     In general, and as described briefly above, modern advanced semiconductor devices, such as memory and logic integrations, require uniform depositions of spacer film formed on different materials including, for example, silicon, metal, and dielectric materials. However, due to differences in material properties, a spacer film deposited by techniques such as ALD and CVD, often show different nucleation behaviors between, for example, metal surfaces and dielectric surfaces. The different nucleation behaviors lead to different deposition thicknesses. Various embodiments of the disclosed subject matter address this specific issue. 
     In various embodiments described herein, the deposition of a silicon nitride (or more generally, Si x N y ) layer on a metal surface or on a dielectric surface enables a subsequent deposition of a silicon oxycarbide (or more generally, SiC x O y ) layer without a substantial delay of SiC x O y  nucleation and growth. The Si x N y  layer may be deposited in situ using, for example, a plasma-enhanced atomic-layer deposition (PEALD) process. The PEALD process occurs in the same chamber immediately prior to the remote-plasma chemical vapor deposition of SiC x O y . The presumably uniform and non-selective coating of the Si x N y  on the metal surfaces and the dielectric surfaces allows the SiC x O y  to deposit on Si x N y  rather than a metal surface, where the SiC x O y  would otherwise experience a nucleation delay. Therefore, a uniform thickness of SiC x O y  is deposited on the feature regardless of the material (e.g., metal or dielectric) present. The PEALD process for depositing Si x N y  has been shown to be effective on, for example, SiN, polycrystalline silicon, and tungsten metal. After the deposition of SiN, the SiC x O y  deposition on these materials is substantially equivalent with little to no differential thickness difference in the deposited SiC x O y  regardless of the material underlying the SiN layer. 
     This strategy of using an ALD of SiN prior to the deposition of SiC x O y  can likely be extended to ensure uniform depositions of SiC x O y  on other dielectric materials and metal materials (e.g., cobalt (Co), copper (Cu), and ruthenium (Ru)) in the semiconductor and allied industries. The ALD Si x N y  serves as the growth-initiation layer. 
     For example, with reference now to  FIG. 3 , a cross-sectional semiconductor structure  300  having a silicon nitride (e.g., Si x N y ) initiation-layer  313  to reduce a thickness difference between a thickness of silicon oxycarbide (e.g., SiC x O y ) deposited over a dielectric material  301 , deposited over a metal material  303 , and deposited over a semiconductor material  305 , in accordance with various embodiments described herein. In a specific exemplary embodiment, the SN initiation layer  313  may be a conformally-deposited ALD layer. In this example, the dielectric material  301  may be silicon nitride (SiN), the metal material  303  may be tungsten (W), and the semiconductor material  305  may be polysilicon. 
     In various embodiments, the dielectric material  301  may comprise, for example, silicon dioxide (SiO 2 ), silicon nitride (Si x N y ) or a variety of other dielectric materials or ceramics such as tantalum pentoxide (Ta 2 O 5 ), aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO 2 ), zirconium dioxide (ZrO 2 ), lanthanum oxide (La x O y ), strontium titanate (SrTiO 3 ), strontium oxide (SrO), or combinations of these and other dielectric materials. 
     In various embodiments, the metal material  303  may include a variety of metals, such as tungsten (W), titanium (Ti), tantalum (Ta), cobalt (Co), copper (Cu), platinum (Pt), and other elemental metals, and alloys thereof, known and used in the art. In various embodiments, the semiconductor material  305  may comprise silicon (including polycrystalline silicon), germanium, and other elemental and compound semiconductor materials known and used in the art. 
     With reference again to  FIG. 3 , generally, the cross-sectional semiconductor structure  300  may comprise planar features (oriented either vertically or horizontally with reference to a surface on an underlying substrate) or may include recessed or protruding features. The methods provided herein are particularly advantageous for structures having recessed features, because they allow for a conformal and uniform deposition of silicon carbide, even when thin layers need to be deposited. The disclosed subject matter can be used for depositing silicon carbide layers having a variety of thicknesses (e.g., about 20 Å to about 400 Å), and are particularly advantageous for depositing thin silicon carbide layers (e.g., having thicknesses of about 20 Å to about 100 Å). 
     The semiconductor structure  300  has a first silicon-oxycarbide layer  307  formed over the dielectric material  301  where the first silicon-oxycarbide layer has a first thickness, t 1 ; a second silicon-oxycarbide layer  309  formed over the metal material  303  having a second thickness, t 2 ; and a third silicon-oxycarbide layer  311  formed over the semiconductor material  305  having a third thickness, t 3 . The third thickness, t 3 , of the third silicon-oxycarbide layer  311  is approximately the same thickness as the first thickness, t 1 , of the first silicon-oxycarbide layer  307 . The second thickness, t 2 , of the second silicon oxycarbide  307  is also approximately the same thickness as either the first thickness t 1  or the third thickness t 3 . In tests applying techniques of the disclosed subject matter, the differential thickness between the first thickness, t 1 , the second thickness, t 2 , and the third thickness, t 3 , has been unmeasurable. Therefore, the differential thickness of the deposited silicon-oxycarbide layer has been well within about 2 nm (i.e., less than about 2 nm. 
     However, even though the disclosed subject matter has been defined with reference to the semiconductor structure  300 , upon reading and understanding the disclosed subject matter, a person of ordinary skill in the art will recognize that the disclosed subject matter may be applied to any vertical structure (e.g., a vertical orientation with reference to the structure being substantially perpendicular to an underlying substrate, not shown) or horizontal (e.g., a horizontal orientation with reference to the structure being substantially parallel to the substrate), or any other orientation with reference to the substrate. 
     With reference now to  FIG. 4 , an exemplary process flow  400  to prepare the Si x N y  initiation-layer for forming over various types of material is shown. A substrate having exposed layers of at least one metal material and at least one dielectric material is transferred to a deposition chamber at operation  401 . To enable a substantially uniform deposition of SiC x O y  on various dielectric and metal materials (as well as other materials, such as, for example, a semiconductor material), an initiation layer in the form of, for example, PEALD Si x N y  is deposited or otherwise formed over the various dielectric and metal materials at operation  403 . As noted above, the Si x N y  deposits substantially uniformly on dielectric materials, metal materials, and semiconductor materials to within, at least, metrology detection limits (e.g., less than about a 2 nm differential step height in the Si x N y  formed over the dielectric versus the Si x N y  formed over the metal). At operation  405 , an SiC x O y  layer is subsequently deposited or otherwise formed over the Si x N y  layer. 
     Consequently, to prevent nucleation delay of SiC x O y  growth on different materials that may exist in a feature, a thin layer of Si x N y  is first deposited. In embodiments, the Si x N y  may be deposited in the same chamber as the subsequent SiC x O y  deposition (e.g., direct plasma). In other embodiments, the Si x N y  may be deposited in a different chamber then the subsequent SiC x O y  deposition (e.g., remote plasma). In various embodiments, the Si x N y  may be deposited or otherwise formed in thicknesses from, for example, about 20 nm to about 200 nm. However, these thicknesses are exemplary only and thickness ranges less than about 20 nm or greater than about 200 nm may also be considered for a given process. 
     The use of Si x N y  as the initiation layer for the SiC x O y  deposition process has advantages over the prior-art process that relied on, for example, using an SiO 2  initiation-layer, as described above with reference to  FIG. 2 . For example, using Si x N y  as the initiation layer does not oxidize the underlying metal onto which it deposits as occurs with the SiO 2  initiation-layer process. The lack of oxidation is advantageous since the oxidation of the metal may increase the resistance of that metal material (e.g., a metal line or via). The increased resistance can result in, for example, decreased switching speed of electronic devices. While there is a chance that the underlying metal material may form a nitride at a surface of the metal, the resistance of metal nitrides is generally lower than that of metal oxides. Consequently, the effect on device speed would not be as severe as that of forming an oxide on the surface of the metal. Another advantage of using Si x N y  as the initiation layer instead of etch and wet clean steps to clean up the surface of the metal and dielectric materials, is that it saves time due to a reduced number of process steps. The reduced number of process steps further translates to reduced production costs. Moreover, the Si x N y  initiation-layer is generally more robust than an SiO 2  initiation-layer. Overall, use of Si x N y  as the initiation layer for the SiC x O y  deposition process generates a better post-deposition profile, as shown and described with reference to  FIG. 3 , above, and further generates a higher device yield of semiconductor devices. 
     Remote Plasma Apparatus 
     As described above, in various embodiments the disclosed subject matter may use a remote-plasma apparatus. As described in more detail below, the remote-plasma apparatus includes a processing chamber, a substrate support for holding the substrate in the processing chamber, a remote plasma source over the substrate support, a showerhead between the remote plasma source and the substrate support, one or more movable members in the processing chamber, and a controller. The one or more movable members may be configured to move the substrate to positions between the showerhead and the substrate support. The controller may be configured to perform one or more operations, including transporting the substrate to the processing chamber, transporting the substrate to the substrate support, and forming a remote plasma of a gas. 
       FIG. 5  shows an example of a cross-sectional schematic diagram of a remote-plasma apparatus  500  with a processing chamber in accordance with various exemplary embodiments. The remote-plasma apparatus  500  includes a processing chamber  520 , which includes a substrate support  513 , such as a pedestal or electrostatic chuck (ESC), to support a substrate  509 . In various embodiments, the substrate may be a silicon wafer. The remote-plasma apparatus  500  also includes a remote-plasma source  510  over the processing chamber  520 , and a showerhead  517  located between the substrate  509  and the remote-plasma source  510 . 
     A gas species  519  can flow from the remote-plasma source  510  towards the substrate  509  through the showerhead  517 . A remote plasma may be generated in the remote-plasma source  510  to produce radicals of a chosen version of the gas species  519 . The remote plasma may also produce ions and other charged species of the gas species  519 . The remote plasma may further generate photons, such as UV radiation, from the gas species  519 . For example, coils  503  may surround the walls of the remote-plasma source  510  and generate a remote plasma in the remote-plasma source  510 . 
     In some embodiments, the coils  503  may be in electrical communication with a radio-frequency (RF) power source or microwave power source (not shown). A commercial example of a remote-plasma source  510  with an RF-power source is the GAMMA® remote-plasma generator product family, manufactured by Lam Research Corporation of Fremont, Calif., USA. Another example of an RF-remote plasma source is the Astron® remote-plasma generator, manufactured by MKS Instruments of Wilmington, Mass., USA, which can be operated at 440 kHz and can be provided as a subunit, bolted onto or otherwise attached, to a larger apparatus for processing one or more substrates in parallel. In some embodiments, a microwave-plasma source can be used with the remote plasma source  540 , as found in the Astex® microwave-plasma source, also manufactured by MKS Instruments. A microwave-plasma source can be configured to operate at a frequency of, for example, 2.45 GHz. 
     Any type of plasma source may be used in the remote-plasma source  510  to create radical species. These plasma types include, for example, capacitively-coupled plasmas, microwave plasmas, DC plasmas, inductively-coupled plasmas, and laser-created plasmas. An example of a capacitively coupled plasma can be a radio-frequency (RF) plasma. 
     In embodiments with an RF-power source, the RF generator may be operated at any suitable power to form a plasma of a desired composition of radical species. Examples of suitable powers include, but are not limited to, powers between about 0.5 kW and about 6 kW. Likewise, the RF generator may provide RF power of a suitable frequency, such as 13.56 MHz for an inductively-coupled plasma. 
     The gas species  519  may be delivered from a gas inlet  501  and into an internal volume of the remote-plasma source  510 . Power supplied to the coils  503  can generate a remote plasma with the gas species  519  to form radicals of the gas species  519 . The radicals formed in the remote-plasma source  510  can be carried, in the gas phase, towards the substrate  509  through the showerhead  517 . 
     With continuing reference to  FIG. 5 , the remote-plasma apparatus  500  may actively cool or otherwise control the temperature of the substrate  509 . In some embodiments, it may be desirable to control the temperature of the substrate  509  to control a rate of a reaction and a uniformity of exposure to the remote plasma during processing. 
     In various embodiments, the remote-plasma apparatus  500  can include movable members  511 , such as lift pins, that are capable, of moving the substrate  509  away from or towards the substrate support  513 . The movable members  511  can be configured to extend between from, for example, about 0 mm to about 125 mm, or more, away from the substrate support  513 . In an exemplary embodiment, the movable members  511  can extend the substrate  509  away from the substrate support  513 , which is hot, towards the showerhead  517 , which is cooler, to cool the substrate  509 . The movable members  511  can also be retracted to bring the substrate  509  towards the hotter substrate support  513 , and away from the cooler showerhead  517 , to heat the substrate  509 . By positioning the substrate  509  via the movable members  511 , the temperature of the substrate  509  can be adjusted. In some embodiments, when positioning the substrate  509 , the showerhead  517  and the substrate support  513  can be held at a constant temperature. 
     In some embodiments, the remote-plasma apparatus  500  can include a type of showerhead that includes temperature control of the showerhead  517 . For example, to permit active cooling of the showerhead  517 , a heat-exchange fluid may be used, such as deionized water or a thermal-transfer liquid. One such thermal-transfer liquid is manufactured by the Dow Chemical Company of Midland, Mich., USA. In some embodiments, the heat-exchange fluid may flow through fluid channels (not shown) in the showerhead  517 . In addition, the showerhead  517  may use a heat exchanger system (not shown), such as a fluid heater/chiller unit (known in the art) to control temperature. In some embodiments, the temperature of the showerhead  517  may be controlled to below about 30° C., such as between about 5° C. and about 20° C. The showerhead  517  may be cooled to lower the temperature of the substrate  509 , such as before and after processing the substrate  509 . 
     In some embodiments, the remote-plasma apparatus  500  can include one or more gas inlets  505  to flow a cooling gas  507  through the processing chamber  520 . The one or more gas inlets  505  may be positioned above, below, and/or to the side of the substrate  509 . Some of the one or more gas inlets  505  may be configured to flow the cooling gas  507  in a direction that is substantially perpendicular to a face of the substrate  509 . In some embodiments, at least one of the gas inlets  505  may deliver the cooling gas  507  through the showerhead  517  to the substrate  509 . A flow rate of the cooling gas  507  for cooling the substrate  509  may be between about 0.1 standard liters per minute (slpm) to about 100 slpm. 
     A controller  515  (described in more detail with reference to  FIG. 6 , below) may contain instructions for controlling parameters for the operation of the remote-plasma apparatus  500 . In various embodiments, the controller  515  will typically include one or more memory devices and one or more processors. The processor may include a central-processing unit (CPU), microprocessor, or computer; analog and/or digital input/output connections; stepper-motor controller boards; and other connections and peripheral devices known in the art. 
     The controller  515  may contain instructions for controlling process conditions and operations (e.g., a process recipe) in accordance with various embodiments of the disclosed subject matter for the remote-plasma apparatus  500 . In some embodiments, the controller  515  controls all of activities of a process tool (not shown). As described below with reference to  FIG. 6 , the controller  515  may execute system control software stored in a mass storage device, loaded into a memory device, and executed on a processor. The system control software may include instructions for controlling the timing, mixture of gases, chamber and/or station pressures, chamber and/or station temperatures, purge conditions and timing, substrate temperatures, RF-power levels, and RF frequencies. The system control software may also control substrate, pedestal, chuck and/or susceptor positions, and other parameters of a particular process, performed by the process tool. The system control software may be configured in any suitable way. For example, various process tool component subroutines or control objects may be written to control operations of the process tool components necessary to carry out various process tool processes in accordance with the disclosed methods. The system control software may be coded in any suitable computer readable programming language. 
     Machines with Instructions to Perform Various Operations 
       FIG. 6  is a block diagram illustrating components of a machine  600 , according to some embodiments, able to read instructions from a machine-readable medium e.g., a non-transitory machine-readable medium, a machine-readable storage medium, a computer-readable storage medium, or any suitable combination thereof) and perform any one or more of the methodologies discussed herein. Specifically,  FIG. 6  shows a diagrammatic representation of the machine  600  in the example form of a computer system and within which instructions  624  (e.g., software, a program, an application, an applet, an app, or other executable code) for causing the machine  600  to perform any one or more of the methodologies discussed herein (e.g., a process recipe) may be executed. 
     In alternative embodiments, the machine  600  operates as a standalone device or may be connected (e.g., networked) to other machines. In a networked deployment, the machine  600  may operate in the capacity of a server machine or a client machine in a server-client network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine  600  may be a server computer, a client computer, a personal computer (PC), a tablet computer, a laptop computer, a netbook, a set-top box (STB), a personal digital assistant (PDA), a cellular telephone, a smartphone, a web appliance, a network router, a network switch, a network bridge, or any machine capable of executing the instructions  624 , sequentially or otherwise, that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term “machine” shall also be taken to include a collection of machines that individually or jointly execute the instructions  624  to perform any one or more of the methodologies discussed herein. 
     The machine  600  includes a processor  602  (e.g., a central processing unit (CPU), a graphics processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a radio-frequency integrated circuit (RFIC), or any suitable combination thereof), a main memory  604 , and a static memory  606 , which are configured to communicate with each other via a bus  608 . The processor  602  may contain microcircuits that are configurable, temporarily or permanently, by some or all of the instructions  624  such that the processor  602  is configurable to perform any one or more of the methodologies described herein, in whole or in part. For example, a set of one or more microcircuits of the processor  602  may be configurable to execute one or more modules (e.g., software modules) described herein. 
     The machine  600  may further include a graphics display  610  (e.g., a plasma display panel (PDP), a light emitting diode (LED) display, a liquid crystal display (LCD), a projector, or a cathode ray tube (CRT)). The machine  600  may also include an alpha numeric input device  612  (e.g., a keyboard), a cursor control device  614  (e.g., a mouse, a touchpad, a trackball, a joystick, a motion sensor, or other pointing instrument), a storage unit  616 , a signal generation device  618  (e.g., a speaker), and a network interface device  620 . 
     The storage unit  616  includes a machine-readable medium  622  (e.g., a tangible and/or non-transitory machine-readable storage medium) on which is stored the instructions  624  embodying any one or more of the methodologies or functions described herein. The instructions  624  may also reside, completely or at least partially, within the main memory  604 , within the processor  602  (e.g., within the processor&#39;s cache memory), or both, during execution thereof by the machine  600 . Accordingly, the main memory  604  and the processor  602  may be considered as machine-readable media (e.g., tangible and/or non-transitory machine-readable media). The instructions  624  may be transmitted or received over a network  626  via the network interface device  620 . For example, the network interface device  620  may communicate the instructions  624  using any one or more transfer protocols (e.g., hypertext transfer protocol (HTTP)). 
     In some embodiments, the machine  600  may be a portable computing device, such as a smart phone or tablet computer, and have one or more additional input components (e.g., sensors or gauges). Examples of such additional input components include an image input component (e.g., one or more cameras), an audio input component (e.g., a microphone), a direction input component (e.g., a compass), a location input component (e.g., a global positioning system (GPS) receiver), an orientation component (e.g., a gyroscope), a motion detection component (e.g., one or more accelerometers), an altitude detection component (e.g., an altimeter), and a gas detection component (e.g., a gas sensor). Inputs harvested by any one or more of these input components may be accessible and available for use by any of the modules described herein. 
     As used herein, the term “memory” refers to a machine-readable medium able to store data temporarily or permanently and may be taken to include, but not be limited to, random-access memory (RAM), read-only memory (ROM), buffer memory, flash memory, and cache memory. While the machine-readable medium  622  is shown in an embodiment to be a single medium, the term “machine-readable medium” should be taken to include a single medium or multiple media (e.g., a centralized or distributed database, or associated caches and servers) able to store instructions. The term “machine-readable medium” shall also be taken to include any medium, or combination of multiple media, that is capable of storing instructions for execution by a machine (e.g., the machine  600 ), such that the instructions, when executed by one or more processors of the machine (e.g., the processor  602 ), cause the machine to perform any one or more of the methodologies described herein. Accordingly, a “machine-readable medium” refers to a single storage apparatus or device, as well as “cloud-based” storage systems or storage networks that include multiple storage apparatus or devices. The term “machine-readable medium” shall accordingly be taken to include, but not be limited to, one or more tangible (e.g., non-transitory) data repositories in the form of a solid-state memory, an optical medium, a magnetic medium, or any suitable combination thereof. 
     Furthermore, the machine-readable medium is non-transitory in that it does not embody a propagating signal. However, labeling the tangible machine-readable medium as “non-transitory” should not be construed to mean that the medium is incapable of movement—the medium should be considered as being transportable from one physical location to another. Additionally, since the machine-readable medium is tangible, the medium may be considered to be a machine-readable device. 
     The instructions  624  may further be transmitted or received over a network  626  (e.g., a communications network) using a transmission medium via the network interface device  620  and utilizing any one of a number of well-known transfer protocols (e.g., HTTP). Examples of communication networks include a local area network (LAN), a wide area network (WAN), the Internet, mobile telephone networks, POTS networks, and wireless data networks (e.g., WiFi and WiMAX networks). The term “transmission medium” shall be taken to include any intangible medium that is capable of storing, encoding, or carrying instructions for execution by the machine, and includes digital or analog communications signals or other intangible medium to facilitate communication or such software. 
     Overall, the disclosed subject matter contained herein describes or relates generally to depositing of otherwise forming uniform thickness layers of silicon carbide, in the various forms as discussed above. However, the disclosed subject matter is not limited to semiconductor fabrication environments and can be used in a number of other environments. Upon reading and understanding the disclosure provided herein, a person of ordinary skill in the art will recognize that various embodiments of the disclosed subject matter may be used with other types of process tools as well as a wide variety of other tools, equipment, and components. 
     As used herein, the term “or” may be construed in an inclusive or exclusive sense. Further, other embodiments will be understood by a person of ordinary skill in the art upon reading and understanding the disclosure provided. Further, upon reading and understanding the disclosure provided herein, the person of ordinary skill in the art will readily understand that various combinations of the techniques and examples provided herein may all be applied in various configurations. 
     Although various embodiments are discussed separately, these separate embodiments are not intended to be considered as independent techniques or designs. As indicated above, each of the various portions may be inter-related and each may be used separately or in combination with other embodiments discussed herein. For example, although various embodiments of methods, operations, and processes have been described, these methods, operations, and processes may be used either separately or in various combinations. 
     Consequently, many modifications and variations can be made, as will be apparent to a person of ordinary skill in the art upon reading and understanding the disclosure provided herein. Further, functionally equivalent methods and devices within the scope of the disclosure, in addition to those enumerated herein, will be apparent to the skilled artisan from the foregoing descriptions. Portions and features of some embodiments, materials, and construction techniques may be included in, or substituted for, those of others. Such modifications and variations are intended to fall within a scope of the appended claims. Therefore, the present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. The abstract is submitted with the understanding that it will not be used to interpret or limit the claims. In addition, in the foregoing Detailed Description, it may be seen that various features may be grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as limiting the claims. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. 
     THE FOLLOWING NUMBERED EXAMPLES ARE SPECIFIC EMBODIMENTS OF THE DISCLOSED SUBJECT MATTER 
     Example 1: In an exemplary embodiment, the disclosed subject matter is a method to produce a substantially uniform, silicon-carbide layer over both of at least one dielectric material and at least one metal material substantially concurrently. The method includes forming a silicon-nitride layer, in the form of Si x N y , over the at least one dielectric material and the at least one metal material, and forming the silicon-carbide layer, in the form of Si x C x O y , over the silicon-nitride layer. 
     Example 2: The method of Example 1, wherein the formed silicon-nitride layer is substantially to prevent a delay in a nucleation and growth of the silicon-carbide layer on the at least one metal material in comparison with a nucleation and growth of the silicon-carbide layer on the at least one dielectric material. 
     Example 3: The method of any one of the preceding Examples, wherein the silicon-carbide layer further comprises hydrogen. 
     Example 4: The method of any one of the preceding Examples, further comprising forming the silicon nitride layer over a semiconductor material. 
     Example 5: The method of any one of the preceding Examples, wherein the at least one metal material comprises at least one material selected from materials including tungsten (W), titanium (Ti), tantalum (Ta), cobalt (Co), copper (Cu), platinum (Pt), and ruthenium (Ru). 
     Example 6: The method of any one of the preceding Examples, wherein the at least one dielectric material comprises at least one material selected from materials including silicon dioxide (SiO 2 ), silicon nitride (Si x N y ), tantalum pentoxide (Ta 2 O 5 ), aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO 2 ), zirconium dioxide (ZrO 2 ), lanthanum oxide (La x O y ), strontium titanate (SrTiO 3 ), and strontium oxide (SrO). 
     Example 7: The method of any one of the preceding Examples, wherein the silicon-carbide layer in the form of SiC x O y  is a silicon-oxycarbide layer. 
     Example 8: In an exemplary embodiment, the disclosed subject matter describes a method for forming a silicon-carbide layer. The method includes forming a silicon nitride initiation-layer, in the form of Si x N y , substantially simultaneously over at least a dielectric material and a metal material. The silicon nitride initiation-layer is to serve as a growth-initiation layer. The silicon-carbide layer, in the form of SiC x O y ; is formed over the silicon nitride initiation-layer. The formed silicon nitride initiation-layer is to substantially prevent a delay in a nucleation and growth of the silicon-carbide layer on the metal material in comparison with a nucleation and growth of the silicon-carbide layer on the dielectric material. 
     Example 9: The method of Example 8, further comprising forming the silicon nitride initiation-layer over a semiconductor material substantially simultaneously with the formation of the silicon nitride initiation-layer over at least the dielectric material and the metal material. 
     Example 10: The method of any one of the preceding Examples 8 et seq., wherein the silicon-carbide layer comprises at least one of doped silicon-carbide and undoped silicon-carbide. 
     Example 11: The method of any one of the preceding Examples 8 et seq., wherein a differential thickness between the formed silicon-carbide layer over the dielectric material and the metal material is less than about 2 nm. 
     Example 12: The method of any one of the preceding Examples 8 et seq., further comprising forming the silicon nitride initiation-layer substantially concurrently over combinations of different types of dielectric materials and different types of metal materials. 
     Example 13: The method of any one of the preceding Examples 8 et seq., wherein the silicon-carbide layer further comprises hydrogen. 
     Example 14: In an exemplary embodiment, the disclosed subject matter describes a method for forming a silicon-carbide layer. The method includes forming layers of at least one metal material and at least one dielectric material in a deposition chamber on a substrate, forming silicon nitride in the form of Si x N y  as an initiation-layer over the at least one metal material and the at least one dielectric material on the substrate, and subsequently forming at least one layer over the silicon nitride where the at least one layer includes materials selected from materials including silicon carbide, in the form of Si x C y , silicon carbon nitride, in the form of Si x C y N z , silicon oxycarbonitride, in the form of SiC x N y O z , and silicon oxycarbide, in the form of Si x C y O z . 
     Example 15: The method of Example 14, wherein the Si x N y  is formed in the same chamber as the subsequent SiC x O y  deposition in a direct-plasma operation. 
     Example 16: The method of any one of the preceding Examples 14 et seq., wherein the Si x N y  is formed in a different chamber then the subsequent SiC x O y  deposition in a remote-plasma operation. 
     Example 17: The method of any one of the preceding Examples 14 et seq., wherein the Si x N y  is formed to have a thickness from about 20 nm to about 200 nm. 
     Example 18: The method of any one of the preceding Examples 14 et seq., wherein the Si x N y  is formed to have a thickness less than about 20 nm. 
     Example 19: The method of any one of the preceding Examples 14 et seq., wherein the Si x N y  is formed to have a thickness greater than about 200 nm. 
     Example 20: The method of any one of the preceding Examples 14 et seq., wherein the silicon carbide, the silicon carbon nitride, the silicon oxycarbonitride, and the silicon oxycarbide, can comprise at least one of doped and undoped versions of the listed silicon-based compounds.