Diamond structure for tools

Abstract

A tool substrate including at least one sidewall includes at least one diamond layer having a thickness between 10 nanometers and 1000 nanometers and formed from diamond grains having a size of no more than 50% of the thickness of the diamond layer, and a diamond coating is deposited on the surface of the substrate on the at least one sidewall.

Description

[Technical Field]

[0001] This application is a continuation-in-part of U.S. Patent Application No. 17 / 869,491, filed July 20, 2022, and claims the benefit of U.S. Provisional Application No. 63 / 223,752, filed July 20, 2021, both of which are incorporated by reference herein in their entireties.

[0002] This disclosure relates to the field of diamond and other materials and coatings for improving tool properties. More specifically, a diamond bump structure and manufacturing method for wafer support tools is disclosed. [Background technology]

[0003] There is a need for tools with coatings and structures that improve performance, for example, tools can be coated to improve hardness, reduce wear, reduce chemical reactivity, or increase or decrease frictional properties.

[0004] As an example, semiconductor wafers can be processed using vacuum or electrostatic chuck tools coated with a material that reduces wear. The coated chuck tool must support and move the wafer through the many steps of wafer lithography and processing with nanometer-scale precision. Unfortunately, the wafer can twist or sag. When the wafer is lowered onto the wafer chuck, friction between the wafer and the chuck tool can prevent the wafer from being flattened or moved into position. To reduce these frictional effects, the contact area between the wafer and the chuck tool can be reduced by providing raised areas of approximately uniform height, usually regularly spaced, on the chuck tool. These raised areas, known as burls, help reduce friction and can cause the wafer to move across the burls as it is flattened and placed on the chuck tool. Uneven or irregularly shaped burls can wear or damage the wafer.

[0005] Materials, structures and procedures are needed that reduce or eliminate problems related to tool friction and wear. [Brief explanation of the drawings]

[0006] Non-limiting and non-exhaustive embodiments of the present disclosure are described with reference to the following figures, in which like reference numerals refer to like parts throughout the various views unless otherwise specified.

[0007] [Figure 1] 1A and 1B are cross-sectional and top views of a conformal diamond coated tool surface having protrusions. [Figure 1C] FIG. 1C is a photograph of a cross section of a conformal diamond coated protrusion. [Figure 1D] FIG. 1D shows selected diamond grain sizes. [Figure 2] FIG. 2 illustrates one embodiment of a process for producing a conformal diamond coated tool surface. [Figure 3] FIG. 3 shows one embodiment of a substrate including various protrusions, cavities, sidewalls, and edges. [Figure 4] FIG. 4 illustrates one embodiment of a semiconductor wafer handling tool. DETAILED DESCRIPTION OF THE INVENTION

[0008] In some embodiments, such as those described in the disclosed figures and specification, a substrate or tool, such as a wafer handler or wafer chuck, can include a surface having at least one protrusion. The substrate or tool can be coated with one or more diamond layers, or diamond layers combined with metal, ceramic, or other material layers, coatings, or films. Such diamond layers, films, or coatings are formed from diamond particles sized such that 90% of the particles are between 200 nanometers and 300 nanometers, and the diamond coating is deposited on the at least one protrusion at temperatures below 600, 500, or 450 degrees Celsius, respectively. Dopants can be used to provide the necessary electrical conductivity for the electrostatic wafer chuck.

[0009] In some embodiments, the at least one protrusion is one or more burls that extend at least partially above the tool surface and are capable of supporting a wafer or other object.

[0010] In some embodiments, the diamond coating is formed to have grains of equal size less than 1 micron. The diamond coating can be formed to continuously or partially cover the projections of the tool or bur.

[0011] In some embodiments, the diamond coating has a thickness of between 200 nanometers and 100 microns. The diamond coating can be uniformly thick over selected areas of the tool or can be conformal over areas of the tool.

[0012] In one embodiment, a method of diamond coating a tool includes providing a tool with a surface having at least one protrusion and forming a diamond coating on the at least one protrusion. The diamond coating can be formed from diamond particles sized such that 90% of the particles are between 200 nanometers and 300 nanometers in size. The diamond coating can be deposited on the at least one protrusion at a temperature of less than 500°C.

[0013] 1A and 1B are cross-sectional (FIG. 1A) and top (FIG. 1B) views of a portion of a tool 100A. The tool 100A includes a substrate 112 having a surface 114. Also present are protrusions 120 extending away from the substrate 112. These protrusions 120 can be coated with a diamond film 130 that covers the protrusions 120 (e.g., diamond film portion 132) and other portions of the tool surface 114 (e.g., diamond film portion 134) to provide friction reduction, protection, heat transfer, or other desired properties. In some embodiments, the diamond film 130 conformally coats the protrusions, with the coating thickness remaining constant or varying by less than 500, 300, or 100 nanometers across each of the protrusions 120. The tool 100A can be coated entirely with a diamond film, coated on one or more sides, or coated in selected areas.

[0014] The tools can include, but are not limited to, precision carriers, grippers, lifters, or other handling tools. Tools can also include needles, pins, injectors, nano- or micro-pipes, fluid handling channels, or manifolds. Additionally, tools can be used for drilling, cutting, grinding, polishing, or insertion.

[0015] In some embodiments, the tool can be a semiconductor wafer handling tool, such as a wafer chuck, wafer holder, wafer stage, wafer table, wafer substrate, die scanner, chemical mechanical polishing (CMP) wafer table, or wafer transporter. An electrostatic wafer chuck or other electrically active tool can be provided with p- or n-doping of diamond film. In other embodiments, tools where nanoscale protrusions are desired or applied to affect mechanical, electrical, or chemical properties can be coated with diamond material. In still other embodiments, the tool can be a sensor or other system that applies nanoscale protrusions to provide multipoint contact with other materials or the environment. For example, a diamond-coated sensor can be integrated into a wafer chuck.

[0016] In some embodiments, the substrate material of tool 100A can be Si, SiC, SiSiC, amorphous silicon, diamond-like carbon, metal-doped oxide glass materials; polymeric materials; ceramics including quartz, sapphire, etc.; metals and metal alloys; and mixtures and combinations thereof.

[0017] In some embodiments, the protrusions can include burls, mesas, bumps, pins, islands, surface structures, nano-protrusions, etc. According to one embodiment, the protrusions on the wafer chuck can have a size, spacing, and composition that allows for maintaining a substantially uniform pressure across the surface of the wafer and for substantially uniformly distributing the force between the protrusions and the substrate.

[0018] In one embodiment, protrusions for wafer processing can include burls formed on a wafer tool by selective growth. Alternatively, the burls can be formed by applying photoresist, patterning the photoresist, and dissolving the unprotected areas. In yet other embodiments, the burls can be formed on the tool using laser sintering or other additive manufacturing techniques. The burls can be formed from the substrate material, thin films deposited on the substrate, low CTE glass ceramics such as cordierite, silicon carbide (SiC), SiSiC, aluminum nitride, or can include SiC in the form of a composite material such as reaction-bonded SiC.

[0019] In some embodiments, many hundreds or thousands of burls can be distributed across a wafer tool, with each wafer tool typically having a diameter of 100 mm, 150 mm, 200 mm, 300 mm, or 450 mm. The tips of the burls typically have a small area, e.g., less than 1 square millimeter. The burls can have a width (e.g., diameter) of 0.5 mm or less. In one embodiment, the burls have a width (e.g., diameter) ranging from about 200 μm to about 500 μm. The spacing between the burls can be between about 1.5 mm and about 3 mm.

[0020] The burls can be arranged to form a pattern and / or have a periodic arrangement. The burl arrangement can have regular triangular, hexagonal, square, or radial symmetry, which can be varied to provide the required force distribution from the wafer tool to the wafer. Alternatively, the burls can be arranged in a semi-random, random, or partially symmetrical layout. The burls can have the same shape and dimensions throughout their height, but are commonly dome-shaped, conical, hemispherical, pyramidal, needle-shaped, or tapered. Typically, the burls protrude from the wafer tool by a distance ranging from about 1 μm to about 5 mm, and often from about 5 μm to about 250 μm. For best wafer processing results, the burls can be formed with consistent dimensions. For best wafer processing results, variation between the heights of different burls is minimized.

[0021] In some embodiments, the burrs or other protrusions coated with diamond film 120 may include coatings of various diamond, diamond-like, or diamond-containing materials and structures. For purposes of this disclosure, diamond refers to sp 3 It refers to the crystalline structure of carbon atoms bonded to other carbon atoms in a tetrahedral coordinated lattice known as bonding. Each carbon atom can be surrounded and bonded by four other carbon atoms, each located at the tip of a regular tetrahedron. In some embodiments, the tetrahedral bonding arrangement of carbon atoms may be irregular or distorted, or may deviate from the standard tetrahedral arrangement of diamond described above. Such distortion generally results in some bonds being longer and others being shorter, and the bond angles between bonds changing. Furthermore, tetrahedral distortion changes the properties and characteristics of carbon, resulting in sp 3 Carbon bonded in the configuration (i.e. diamond) and sp 2The distorted tetrahedral bonded carbon structure effectively lies between the properties of carbon (i.e., graphite) bonded in a distorted tetrahedral configuration. An example of a material with carbon atoms bonded in a distorted tetrahedral configuration is amorphous diamond. In one embodiment, the amount of carbon in amorphous diamond is at least about 90%, with at least about 20% of such carbon being bonded in a distorted tetrahedral configuration. Amorphous diamond can have a higher atomic density than diamond. In other diamond film embodiments, diamond-like carbon can be formed as a carbonaceous material having carbon atoms as the majority element, with a substantial amount of carbon atoms bonded in a distorted tetrahedral configuration. Diamond films can contain various other elements as impurities or dopants, including, but not limited to, hydrogen, sulfur, phosphorus, boron, nitrogen, silicon, or tungsten. This can be useful, for example, in modifying the electrical or chemical diamond film properties to support tool requirements.

[0022] Diamond deposition can be performed by any process, including, but not limited to, chemical vapor deposition (CVD) and physical vapor deposition (PVD). A wide variety of deposition methods can be used. Examples of deposition methods include hot filament CVD, rf-CVD, laser CVD (LCVD), laser ablation, conformal diamond coating process, metal organic CVD (MOCVD), sputtering, thermal evaporation PVD, ionized metal PVD (IMPVD), electron beam PVD (EBPVD), reactive PVD, cathodic arc, etc.

[0023] In some embodiments, diamond films can be deposited at relatively low temperatures below 600°C, 500°C, or 450°C using an activating medium such as plasma, argon gas, and a carbon source such as methane. In other embodiments, deposition can occur at temperatures between 375°C and 425°C. Compared to the traditional temperatures of 700°C to 800°C for diamond film growth, these low temperatures can significantly reduce thermal warpage of tools, including wafer processing tools. Warpage is reduced in partially coated tools, tools with a diamond coating on one side, tools with a diamond coating on both sides, or tools completely coated with a diamond coating.

[0024] In some embodiments, the deposition gases are ignited to produce a continuous, thin, conformal diamond layer. The type and structure of the deposited diamond depends on the seeding method used. Larger grain seeds result in microcrystalline diamond with higher hardness. Smaller grain sizes of nanocrystalline diamond result in lower surface roughness.

[0025] The properties of diamond films can be measured and characterized using Raman spectroscopy. Cubic diamond has a single Raman-active first-order phonon mode at the center of the Brillouin zone. The presence of sharp Raman lines allows cubic diamond to be detected against a background of graphite or other carbon crystal types. Small shifts in band wavenumber can indicate the composition and properties of the diamond. In some embodiments, the full width at half maximum (FWHM) obtained from Raman characterization of diamond films formed as described in this disclosure may be between 5 and 10.

[0026] In some embodiments, the diamond film is conformally deposited as a continuous layer on the surface 114 of the tool 100A. Alternatively, the diamond film can be formed only in selected areas by masking, etching, or using appropriate growth enhancement or growth reduction techniques. In some embodiments, the thickness of the diamond film can be constant across the surface, while in other embodiments, the thickness can vary with position.

[0027] In some embodiments, the diamond film thickness may be constant across the surface, while in other embodiments, the thickness may vary with position. The diamond coating thickness may be between 200 nm and 100 microns. In some embodiments, the diamond coating thickness may be between 200 nm and 10 microns. In some embodiments, the diamond coating thickness may be between 200 nm and 1 micron. In some embodiments, the diamond particle size may be between 200 nm and 300 nm. In some embodiments, 90% of the diamond particles are between 200 nm and 300 nm. In other embodiments, 95% of the diamond particles are between 200 nm and 300 nm, and in still other embodiments, 99% of the diamond particles are between 200 nm and 300 nm.

[0028] FIG. 1C is a photograph of a cross section of a conformal diamond coated protrusion.

[0029] Figure 1D shows selected diamond particle sizes. As shown, 200 nm, 400 nm, and 1 micron particle sizes are shown. As can be seen, the particle sizes are fairly uniform, with at least 90% of the diamond grains being between 200 nm and 300 nm in size.

[0030] Figure 2 shows one embodiment of a process 200 for producing a diamond-coated tool surface. In the first process step 210, diamond seeds are attached to the tool surface. Suitable diamond seeds, having a size between 5 nm and 25 μm, can be attached to the substrate by ultrasonication. This increases nucleation density, improves uniformity, and accelerates growth rates. Seeding techniques can be varied as needed to provide the desired diamond film thickness and grain size.

[0031] In the second process step 212, the temperature, pressure, and precursor gas ratios can be selected to achieve the desired film thickness and grain size. In some embodiments, the precursor gases can include methane, hydrogen, and argon. If desired, small amounts of other gases such as boron, nitrogen, or phosphorus can be used. Low temperature growth at pressures of 10-100 Torr can be selected.

[0032] In the third process step 214, a diamond film is grown in either a hot filament CVD reactor or a microwave plasma reactor. In the case of an HFCVD reactor, a tungsten or tantalum filament is used, which can be carburized prior to nucleation and growth. In some embodiments, the grown diamond film can have a grain size classified as microcrystalline (typically 500 nm or larger), nanocrystalline (typically 10-500 nm), or ultrananocrystalline (typically 2-10 nm).

[0033] 3 shows a cross section of one embodiment of a tool 300 including a representative substrate 302 having a bottom surface 304, a top surface 306, and a sidewall or edge 308. Various protrusions 310 (vertically edged) and 312 (curved or hemispherical) are shown. Similarly, various cavities 320 (vertically edged) and 322 (curved or hemispherical) are shown. In some embodiments, the cavities may extend entirely through the substrate. In one embodiment, a conformal, continuous diamond coating 330 may be deposited over the bottom surface 304, top surface 306, and sidewall or edge 308.

[0034] FIG. 4 shows a perspective view of one embodiment of a wafer-processing tool 400, including a sidewall 410 and an inner ring 412. The surface 420 is coated with a diamond layer and includes multiple protrusions 430 that can be used to support a wafer. The cavities or holes 432 and 434 may be part of a vacuum system used to hold a wafer (not shown) against the wafer-processing tool 400. The thickness of the diamond layer may range from 300 nanometers to 3000 nanometers, 400 nanometers to 800 nanometers, or 500 nanometers to 700 nanometers. In some embodiments, the diamond grain size is 50-500 nanometers, and at least 50%, 60%, 70%, 80%, or 90% of the diamond grains may be within this grain size range.

[0035] Example 1 - In another embodiment, nanocrystalline diamond is deposited on a SiSiC substrate with a diameter of 2 inches to 12 inches. The SiSiC component can have a burr (or extending protrusion) with a flat top and sloped sidewalls with a predetermined inclination. The thickness of the burr can be about 1 to 1.5 mm. Different size seeds can be used. High nucleation densities can be obtained using seeds of 20 to 30 nanometer diamond particles, along with 10, 15, and 25 nanometer particles, to achieve a uniform diamond coating across a 12-inch SiSiC wafer.

[0036] Example 2 - After deposition of a continuous diamond layer or film, the diamond layer or film may be etched, for example, using an aluminum mask. Islands of square and circular structures, including but not limited to those formed as SiC / SiSiC barrels or other substrates, are defined. By employing different seed mixtures, the final thickness and grain size of the diamond can be selected.

[0037] Example 3 - Tools with structures typically configured as pyramids or cones with tip radii between 200 nm and 2 μm can be fabricated by reactive ion etching using Al as a mask.

[0038] In some embodiments, single or multiple diamond layers or films suitable for coating tools can be components of multilayer coating or film systems applied to a wide variety of substrates. Such diamond layers or films can include multilayer structures to enable or enhance various applications or features, including those providing light redirection, interference, cover glass, protective covers, displays, windows, chemical, thermal, or mechanical protection. Applications or components supporting multilayer diamond layers, films, or coatings can include, but are not limited to, visible or infrared optics, windows, optical waveguides, semiconductors, semiconductor coatings, and robust or durable coatings for electrical, manufacturing, or tooling applications. Other applications for diamond multilayer coatings include use with biological substrates or medical devices, or in batteries, fuel cells, electrochemical systems, chemical sensors, general sensing, or integration with other advanced materials.

[0039] As used in this disclosure, the terms "layer," "film," and "coated" can be used interchangeably and refer to a thinly deposited, chemically formed, grown, or otherwise arranged material on a substrate, which itself may be a layer, film, or coating. Diamond layers or films include intrinsic diamond, diamond-like materials, or diamond containing small amounts of graphite or other materials. The diamond lattice structure can be selectively modified, resulting in various sputtering sites arranged by selective seeding or etching, nucleation or growth process parameters including gas composition, pressure, and temperature, among other parameters, selective laser annealing, particle bombardment or doping, or the use of laser pulses to grow diamond. 2 / sp 3 It may comprise a carbon material.Modification of the diamond layer or film by oxygen termination, hydrogen termination, chlorine or fluorine functionalization are further embodiments.

[0040] In some embodiments, diamond layers intended for sensing, waveguide, or electronic uses can benefit from doping, including p-doping and n-doping. Dopants can also be added, including, but not limited to, P, B, Li, or H. In some embodiments, ion tracks can be further generated by introducing a minimal amount of acceptor dopant atoms into the diamond lattice. The generation of ion tracks requires a non-critical concentration of vacancies, e.g., 10 in the single crystal bulk volume. 22 / cm 3This can include the generation of less than 100 kJ / cm2 and a reduction in the diamond layer's resistivity. For example, acceptor dopant atoms can be introduced using ion implantation at approximately 80°K to 600°K. In other embodiments, acceptor dopant atoms can be introduced using ion implantation at low concentrations at 293°K to 298°K. The acceptor dopant atoms can be p-type acceptor dopant atoms. P-type dopants can include, but are not limited to, boron, hydrogen, and lithium. In one embodiment, an ion track can be created that acts as a pathway for introducing larger substitutional dopants. This allows the substitutional dopant atoms to be placed into the diamond lattice via the ion track. For example, larger substitutional dopant atoms have been placed using ion implantation at approximately 78°K or below for energy implants below 500 keV. Implanting at 78°K or below can freeze out vacancies and interstitials in the diamond lattice while maximizing substitutional implantation of substitutional dopant atoms. Larger substitutional dopant atoms can be, for example, but are not limited to, phosphorus, nitrogen, sulfur, and oxygen. Such larger substitutional dopant atoms may be introduced at much higher concentrations than the acceptor dopant atoms. The higher concentration of larger substitutional dopant atoms is approximately 9.9×10 17 / cm 3 of phosphorus and 8 × 10 17 ~2×10 18 / cm 3 As another example, nitrogen can range from 9×10 18 / cm 3 It can be injected at concentrations up to 1000 mg / kg.

[0041] In some embodiments, the diamond layer may have an sp2 concentration of less than 20% by volume of the diamond layer. <111> or <100> It may have at least 80% grain orientation in any one of the crystallographic directions. In yet another embodiment, the highly oriented diamond film comprises different crystallographic orientations in selected regions or layers, <111> and <100> Each crystal direction is dominant.

[0042] The properties of diamond in multilayer coating or film systems can be measured and characterized using Raman spectroscopy. Cubic diamond has a single Raman-active first-order phonon mode in the center of the Brillouin zone. The presence of sharp Raman lines allows cubic diamond to be detected against a background of graphite or other carbon crystal types. Small shifts in band wavenumber can indicate the composition and properties of diamond. In some embodiments, the full width at half maximum (FWHM) obtained from Raman characterization of diamond layers or films formed as described herein may be between 5 and 15. In other embodiments, the diamond layer may have a Raman spectroscopic characteristic of diamond (approximately 1332 nm) compared to the peak graphite band (1400 to 1600 nm) by Raman analysis of at least 0.5:1 or greater. In other embodiments, the diamond layer may have physical properties such as a Vickers hardness, measured by nanoindentation, of at least 12 gigapascals or greater than 20 gigapascals. In other embodiments, the diamond layer may be measured to exert a compressive stress of less than 50 gigapascals.

[0043] In some embodiments, substantially single-crystal diamond can be formed on at least a portion of the substrate. In other embodiments, polycrystalline diamond or diamond-like material can be formed on all or at least a portion of the substrate. In some embodiments, polycrystalline diamond particles of sizes less than 1 micron (1000 nanometers) and greater than 500 nanometers can be used. In other embodiments, the polycrystalline diamond or diamond-like material can include ultrananocrystalline grain sizes (2-10 nanometers), nanocrystalline grain sizes (10-500 nanometers), or microcrystalline grain sizes (500 nanometers or greater). In some embodiments, the diamond grain size can include a range of grain sizes, including larger and smaller grains. In some embodiments, the diamond layer can be formed with grains less than 1 micron. In some embodiments, the grain size can vary by more than 50%, 100%, 200%, or 500% of the average diamond grain size. In other embodiments, the diamond grain size can be maintained within 50%, 20%, or 10% of the average grain size. In some embodiments, 50%, 60%, 80%, or 90% of the diamond particles can be between 50 nanometers and 500 nanometers in size. In some embodiments, the diamond layer can be formed from at least 90% nanocrystalline diamond and can have diamond particles between 2 nanometers and 500 nanometers in size. In some embodiments, the diamond layer can be formed from at least 90% microcrystalline diamond and can have diamond particles between 500 nanometers and 1000 nanometers in size. In other embodiments, the diamond particles can be between 500 nanometers and 1000 nanometers in size. In other embodiments, 90% of the diamond particles can be between 200 nanometers and 300 nanometers in size.

[0044] In some embodiments, the size of the diamond particles within the diamond layer can be controlled to improve certain optical, thermal, or mechanical properties of the diamond layer, including the multilayer coating or film system. For example, optical transparency can be increased by using ultrananocrystalline or nanocrystalline sized particles between 2 nanometers and 30 nanometers in size.

[0045] In some embodiments, the thickness of the diamond layer can be selected to be between 200 nanometers and 100 microns. Typically, the size of the diamond particles is 50% or less of the thickness of the diamond layer. In some embodiments useful for optical coatings, the thickness of the diamond layer is between 20 nanometers and 200 nanometers. For example, in one embodiment, glass or other transparent materials can be coated with a diamond film having a thickness between 10 nanometers and 1000 nanometers. When used in optical transmission systems, the diamond film provides a transmittance through the glass substrate and diamond film of greater than 0.60, 0.70, 0.80, or 0.90 at a wavelength of 550 nanometers, less than 0.60, 0.70, 0.80, or 0.90 at wavelengths from 350 nanometers to 450 nanometers, and less than 0.60, 0.70, 0.80, or 0.90 at wavelengths from 750 nanometers to 850 nanometers. In other embodiments of the optical transmission system, the diamond film provides optical transmission through the glass substrate and diamond film, with a transmittance greater than 0.60, 0.70, 0.80, or 0.90 at wavelengths between 500 nanometers and 600 nanometers, 530 nanometers and 570 nanometers, or 540 nanometers and 560 nanometers. In some embodiments, glass or other transparent materials can be coated with diamond films that provide haze of less than 20% for thick diamond layers (e.g., in the range of 1 micron to 10 microns), less than 10% for thin diamond layers (e.g., in the range of 200 nanometers to 1000 nanometers), and less than 5% for very thin diamond layers (e.g., 200 nanometers or less). In other embodiments, thicker diamond layer coatings, up to 10 microns, can be used to improve mechanical, frictional, or thermal properties.

[0046] The diamond layer can have a substantially uniform thickness across all or a defined portion of the surface or substrate. In other embodiments, the thickness can vary across portions of the surface or substrate. In some embodiments, the diamond layer can be conformal when it extends over cavities, depressions, or protrusions in the substrate or surface. In some embodiments, the diamond layer can be thinned or thickened from one or more locations on the substrate. In some embodiments, the thinning or thickening can be less than 20%, 10%, 6%, or 3% of the diamond layer thickness on the substrate.

[0047] Multiple diamond layers differentiated by composition, crystal structure, dopant, grain size, or grain size distribution may be part of a multi-layer coating or film system applied to a substrate. Individual diamond layers may be layered on top of diamond or non-diamond materials. In some embodiments, the physical parameters of the diamond layers may vary continuously or semi-continuously vertically or laterally through the layer.

[0048] The diamond layer can be deposited using selective seeding techniques and structured as needed. The seed layer can include selective deposition or the use of an etched seed region. In some embodiments, the nanocrystalline diamond can be deposited directly or in solution.

[0049] The diamond layer can be deposited, with or without seeding, on a variety of substrates, including but not limited to glass, ceramic, oxide, or metal. For example, the substrate can be silicon oxide, SiO2, fused silica, quartz, sapphire, gallium nitride (GaN), gallium arsenide (GaAs), and refractory metals. Furthermore, the substrate material can contain carbon-carbon bonds, allowing for integration with other materials such as SiC, graphene, carbon nanotubes (CNTs), single-crystal and polycrystalline diamond materials, and material combinations. The substrate can be transparent, semi-transparent, or opaque at a selected wavelength or wavelength range. For example, in some embodiments, the substrate can have a transmittance of 80% or greater at one of the optical or infrared wavelengths. In some embodiments, the diamond layer has a transparency greater than about 80%, such as 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, or about 95%, including all ranges and values ​​therebetween. In certain embodiments, the diamond layer has a thickness of, for example, between 30 nanometers and about 150 nanometers (e.g., about 30 nanometers, 40 nanometers, 50 nanometers, 60 nanometers, 70 nanometers, 80 nanometers, 90 nanometers, 100 nanometers, 110 nanometers, 120 nanometers, 130 nanometers, 140 nanometers, about 150 nanometers, including all ranges and values ​​therebetween). Additionally, the diamond layer can have a root mean square (RMS) roughness of less than 7 nanometers. In some embodiments, the diamond layer may have an RMS roughness of less than 50%, 40%, 30%, 20%, or 10% of the film thickness, hi some embodiments, the diamond layer may have an RMS roughness of less than 20% of the diamond layer thickness.

[0050] In some embodiments, various processes can be used to improve the quality of diamond or other films. For example, the substrate can be subjected to dry and / or wet chemical cleaning processes, including, but not limited to, strong or weak acid and / or base cleaning, solvent cleaning, ultrasonic agitation, spray coating, plasma cleaning, ultraviolet (UV) and ozone, tetramethylammonium hydroxide, or any suitable combination of cleaning processes. Plasma cleaning can include subjecting the substrate to plasma derived from various concentrations of argon and / or oxygen. The ozone can be chemical ozone derived from a heat source, or both.

[0051] In some embodiments, prior to deposition of the diamond or diamond-like film, the substrate can be treated by sputtering, evaporation, atomic layer deposition (ALD), chemical vapor, plasma, heat, or one or more forms of deposition of materials, including, but not limited to, oxide and nitride dielectric materials, oxides of metals such as indium, tin, and zinc, or combinations thereof, oxides of graphene such as graphene oxide, reduced fluorinated graphene oxide, oxides of silicon or aluminum, nitrides of aluminum, silicon, titanium, boron, and metals such as tungsten or titanium. Advantageously, in some embodiments, this can reduce differences in thermal expansion coefficients, reduce interlayer and subsurface stress, and enable tuning color and optical losses due to haze or reflectivity.

[0052] In some embodiments, for metals deposited by sputter deposition, power levels can be adjusted and shutter opening times can be varied to achieve a target thickness uniformly across the display glass surface. For oxides and nitrides deposited by ALD, thin films can utilize lower temperatures (including temperatures below 600°C) and / or crystalline structures to achieve optimal integration with the subsequent diamond layer.

[0053] In some embodiments, the substrate can be subjected to a surface functionalization process, which can include wet chemistry surface functionalization, including spray coating, biased spray coating, ultrasonic spray coating, and ultrasonically agitated deposition of a solvent and ketone mixture, including, but not limited to, methanol, acetone, isopropyl alcohol, ethanol, butanol, or pentanol. The functionalized surface can include hydrocarbon chains, hydroxyl bonds, oxygen terminations, or other suitable chemically active materials.

[0054] To promote the growth of diamond films at selected grain sizes or defined regions, substrates can be seeded with diamond crystal grains ranging in size from nanometers to microns. In some embodiments, seed sizes can range from 5 nanometers to 50 nanometers. The seeds can be functionalized or have positive, negative, or neutral zeta potentials. The seed crystals can be in a solvent, dimethyl sulfoxide, oil, photoresist, deionized water, a combination, or a similar type of suspension or matrix. Substrate coverage with diamond crystal seeds can be uniform (105 to 1013 grains per square centimeter), non-uniform, or localized to selected areas using masks, selective spraying, electrospraying, ultrasonic spraying, or other forms of spatially localized application. In some embodiments, seeds of different sizes and characteristics can be used.

[0055] The seeded substrate can be loaded into a chemical vapor deposition (CVD) system under low vacuum pressures ranging from 30 mTorr to 300 Torr. The CVD system can be thermal, microwave, or a combination of thermal and microwave configurations. Thermal CVD can include hot filament, heat wire, light beam, or other, and microwave can include either or both 915 MHz and 2.45 GHz systems. The substrate is then exposed to ions generated from a heat or microwave source, with reactant feed gases including one or more of hydrogen, argon, acetylene, acetone, oxygen, methane, carbon monoxide, carbon dioxide, or other carbon-containing sources. In one embodiment, the diamond can be single-crystal diamond. In another embodiment, the diamond can be polycrystalline diamond. In one embodiment, nanocrystalline diamond can be utilized. The deposition process can be further modified using variable pressure, positive and / or negative stage bias, stage heating and / or cooling, or control of the distance from the stage to the plasma source. The volumes, ratios and flow rates of the reactant and initiator gases, the gas inlet temperature, the substrate temperature, the intermediate electric field from the energy source to the substrate surface, and the chamber pressure can be adjusted so that the grown diamond film exhibits compressive stress rather than tensile stress. In some embodiments, this can hold the display glass layer under compression, increasing the toughness and strength of the display glass. Furthermore, the thermal decomposition and ion energy of the source gas can favor the properties of the diamond by controlling the volume of C₂H₂O hydrocarbon radicals versus C₂ (dimer) hydrocarbon radicals.

[0056] In some embodiments, the deposited diamond film can be further cleaned and exposed to a two-dimensional top layer material such as reduced fluorinated graphene oxide, graphene, graphene oxide, or similar materials. In some embodiments, this provides superhydrophobicity or hydrophobicity without significantly degrading the diamond film's properties, including optical transmittance and / or hardness. In one embodiment, graphene oxide is obtained from a chemical suspension of multilayer graphene oxide, spun onto the diamond film, and then wet-chemically or dry-chemically (plasma-) reduced by incorporating fluorine atoms into the material instead of oxygen.

[0057] In some embodiments, the diamond layer coating the substrate can be subjected to further chemical and mechanical processing, such as reactive ion etching, to produce a bulk-planarized, uniform diamond film of the desired thickness. In one embodiment, the RIE (reactive ion etching) uses CHF3 and CF4 in a 3:1 ratio. Further planarization and / or polishing steps can be utilized to achieve the desired flatness and surface finish.

[0058] Diamond films as described herein can be deposited on a wide variety of substrate types and shapes. Substrates may include Si, SiC, SiSiC, amorphous silicon, diamond-like carbon, metal-doped oxide glass materials; polymeric materials; ceramics, including quartz, sapphire, etc.; metals and metal alloys, or mixtures and combinations thereof. In some embodiments, the substrate may include, but is not limited to, aluminosilicate glass, such as Corning Gorilla Glass®, borosilicate glass, commercial glass, such as BK7, fused silica, quartz, sapphire, indium tin oxide, titanium dioxide, such as crystalline rutile.

[0059] In some embodiments, the substrate morphology and composition can be modified by maskless or masked etching, additive or subtractive photoresist etching, or direct mechanical cutting, drilling, or grinding. In still other embodiments, laser sintering or other additive manufacturing techniques can be used to form the substrate into the desired shape. In some embodiments, doping, sputtering, evaporation, atomic layer deposition (ALD), chemical vapor, plasma, thermal, or other forms of deposition can be used to deposit the various materials previously described in preparation for processing diamond films. In some embodiments, the deposited diamond layer can act as a support for additional diamond or non-diamond films.

[0060] In some embodiments, the substrate may be flat, curved, smoothly continuous, and include sidewalls, edges, beveled edges, or curved edges. The surface may be of one distinct composition or may include multiple compositions. Substrate embodiments may also include single or multiple cavities, depressions, or channels defined therein, as well as protrusions such as pillars or protrusions. In other embodiments, the substrate may include burls, mesas, bumps, pins, islands, irregular or regular surface structures, nanoprotrusions, and the like. According to one embodiment, the cavities or protrusions may be selected to have a predetermined size, spacing, and composition; in other embodiments, the size, spacing, and composition may be random or semi-random.

[0061] The substrate is mechanically rigid and can have a thickness of a millimeter or more, although in some embodiments, the substrate comprises another thin layer of diamond, or a thin layer of metal, ceramic, glass, or other composition. The thickness of such a layer may be less than 1 mm, less than 1 micron, or less than 100 nanometers. Such a layer can act as an intermediate or buffer layer and improve the optical, electrical, thermal, or mechanical properties of the multilayer structure. In some embodiments, the substrate or intermediate layer is transparent and can comprise one or more of a metal (e.g., tungsten or titanium); a ceramic; or a glass (e.g., an aluminosilicate or borosilicate). In some embodiments, the substrate or optically transparent intermediate layer can comprise one or more of titanium oxides, including, but not limited to, indium tin oxide, aluminum oxide, titanium dioxide, magnesium oxide, silicon dioxide, and hafnium oxide. In other embodiments, the substrate or optically transparent intermediate layer can comprise one or more of aluminum, silicon, titanium, or boron nitride. The layer may also include, but is not limited to, a carbon film formed of diamond-like carbon (DLC), amorphous carbon, or nanocrystalline diamond (NCD), or a metal film formed of molybdenum, titanium, tungsten, chromium, or copper, or a ceramic film formed of SiC, TiC, CrC, WC, BN, B4C, Si3N4, TiN, CrN, SiCN, or BCN. When the diamond film has a thickness in the range of 10 nanometers to 1000 nanometers, the thickness of the intermediate or buffer layer can be in the range of 10 nanometers to 100 microns.

[0062] As will be appreciated, the diamond layers, substrates, and thin films of non-diamond materials described can include a variety of embodiments, properties, and combinations, including but not limited to the following additional examples.

[0063] Example 4 - In a fourth example, a transparent diamond layer can be continuously and conformally coated onto a glass substrate to serve as an optically transparent protective coating suitable for smartphones, tablets, or laptops. For example, a substantially uniform, 70-nanometer-thick nanocrystalline film can be deposited, with a grain size ranging from 20 to 70 nanometers. In some examples, the grain size can be diamond grains ranging from 5 to 50 nanometers. The glass substrate can be chemically cleaned using acetone, followed by UV ozone cleaning. Alternatively, float glass or similar substrates can be acid-washed to remove tin or other metallic coatings. In some examples, the glass surface can be functionalized to include hydrocarbon chains derived from solvent decomposition during drying.

[0064] Conventional HFCVD reactors with tungsten, tantalum, or rhenium filaments can be used. The diameter, spacing, and number of filaments can be adjusted to provide optimal results. In one embodiment, the filament diameter is 0.12 to 0.5 mm, the spacing is 8 to 30 mm, and 7 to 28 filaments are used. The chamber can be spherical, rectangular, or cylindrical. In one embodiment, the cylindrical sphere can be sized to have a volume of between 100 and 200 liters and a diameter of between 30 and 150 centimeters.

[0065] The reactor can include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages can be configured to provide substrate deposition temperatures between 500 and 600°C. At these temperature ranges, the diamond layer deposition rate can be between 10 and 100 nanometers per hour.

[0066] Precursor gases containing methane, hydrogen, oxygen, and argon can be introduced into the chamber at a pressure of 10-15 Torr. In particular, the addition of less than 1% oxygen can lower the temperature required to maintain the expected deposition rate, and oxygen preferentially etches sp2 deposition regions. The methane concentration can be between 0.5 and 5% of the total gas volume. The hydrogen concentration can be between 60 and 90% of the total gas volume. The argon concentration can be between 10 and 40% of the total gas volume.

[0067] To ensure a consistent particle size, the substrate can be coated with diamond seeds dispersed in dimethyl sulfoxide (DMSO) or other solvent solutions, including but not limited to ethanol, methanol, IPA, and acetone. In some embodiments, particle sizes of 5 to 50 nanometers can be used.

[0068] In some embodiments, the diamond film is continuous and conformal on the substrate.

[0069] Furthermore, the diamond film has a FWHM of 5 to 7, an sp2 concentration of less than 20% by volume, <111> It has at least 80% grain orientation in the crystallographic direction, a Raman spectroscopic signature of diamond (approximately 1332 nm) between 0.7:1 and 1.2:1 compared to the peak graphite band (1400 to 1600 nm), a Vickers hardness between 20 kJ and 60 gigapascals, and an optical transmittance through the glass substrate and diamond film greater than 0.70 at 550 nanometer wavelength, with a haze of less than 5%.

[0070] Example 5 - In a fifth embodiment, a substrate may be coated with a substantially uniform 100 to 2000 nanometer thick nanocrystalline diamond layer or film having a diamond grain size in the range of 100 to 2000 nanometers. In some embodiments, the deposited grain size may include diamond grains in the range of 5 nanometers to 50 nanometers.

[0071] The reactor can include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages can be configured to provide substrate deposition temperatures between 500 and 800°C. At these temperature ranges, the diamond layer deposition rate can be between 10 and 200 nanometers per hour.

[0072] The substrate can be coated with diamond seeds dispersed in DMSO or other solvent solutions, including, but not limited to, ethanol, methanol, IPA, and acetone. In some embodiments, particle sizes of 5 to 15,000 nanometers can be used, with larger particles typically reduced in size by sonication or other processing steps. In some embodiments, various particle sizes or particle size ranges can be used, including co-deposited small and large particle sizes. In some embodiments, the seeds are deposited in a manner that ensures the film is continuous and conformal on the substrate.

[0073] In some embodiments, the diamond film may have a Young's modulus greater than 80 gigapascals.

[0074] Example 6 - In a sixth embodiment, a transparent substrate may be coated with multiple layers, including diamond, ceramic, or metal layers. In some embodiments, a substantially uniform 5 to 50 nanometer thick nanocrystalline diamond layer may be deposited, having a grain size in the range of 5 to 50 nanometers.

[0075] The reactor can include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages can be configured to provide substrate deposition temperatures between 500 and 600°C. At these temperature ranges, the diamond layer deposition rate can be between 10 and 100 nanometers per hour.

[0076] In the foregoing description, reference has been made to the accompanying drawings that form a part hereof, and in which are shown, by way of illustration, specific exemplary embodiments in which the present disclosure may be practiced. These embodiments have been described in sufficient detail to enable those skilled in the art to practice the concepts disclosed herein, and it is to be understood that changes can be made to the various disclosed embodiments and other embodiments can be utilized without departing from the scope of the present disclosure. Accordingly, the foregoing detailed description is not to be construed in a limiting sense.

[0077] References throughout this specification to "one embodiment," "one embodiment," "one example," or "one example" mean that a particular feature, structure, or characteristic described in connection with an embodiment or example is included in at least one example of the present disclosure. Thus, the appearances of the phrases "in one embodiment," "in one embodiment," "in one example," "one example," or "one example" in various places throughout this specification do not necessarily all refer to the same embodiment or example. Furthermore, particular features, structures, databases, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. Additionally, it should be understood that the figures provided herein are for illustrative purposes for persons skilled in the art, and that the drawings are not necessarily drawn to scale.

[0078] Many modifications and other embodiments of the invention will come to mind to one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. It is understood, therefore, that the invention is not limited to the particular embodiments disclosed, and modifications and embodiments are intended to be included within the scope of the appended claims. It is also understood that other embodiments of the invention can be practiced in the absence of elements / steps not specifically disclosed herein.

Claims

1. a substrate having a surface including at least one sidewall; and 1. A structure comprising: a diamond layer having a thickness between 10 nanometers and 1000 nanometers, the diamond layer being formed from diamond grains having a size of 50% or less of the thickness of the diamond layer; and a diamond coating deposited on a surface of the substrate on at least one of the sidewalls.

2. The structure of claim 1 , wherein the sidewalls are defined by protrusions extending away from the substrate.

3. The structure of claim 1 , wherein the sidewall is defined by a cavity extending into the substrate.

4. 10. The structure of claim 1, wherein the diamond layer is formed continuously over the surface of the substrate.

5. 10. The structure of claim 1, wherein the diamond layer is formed to partially cover a surface of the substrate.

6. 10. The structure of claim 1, wherein the diamond layer is formed conformally over the surface of the substrate.

7. 10. The structure of claim 1, wherein the diamond layer is thin or thick, with a thickness of less than 20% across the surface of the substrate.

8. 10. The structure of claim 1, wherein the diamond layer has a uniform thickness across a selected area of ​​the surface of the substrate.

9. 10. The structure of claim 1, wherein the diamond layer is at least one of a plurality of diamond and non-diamond layers formed over at least a portion of a surface of the substrate.

10. 10. The structure of claim 1, wherein the diamond layer on the surface and sidewalls is formed with 50% of the grains being between 2 nanometers and 500 nanometers in size.

11. The structure of claim 1 , wherein the substrate is opaque at optical wavelengths.

12. 10. The structure of claim 1, wherein the diamond layer is deposited at less than 600°C.

13. 1. A method for depositing a layer, comprising: providing a substrate having a surface including at least one sidewall; and 1. A method for depositing a layer, comprising depositing a diamond layer having a thickness between 10 nanometers and 1000 nanometers, said diamond layer being formed from diamond grains having a size of 50% or less of the thickness of said diamond layer, said diamond coating being deposited on a surface of a substrate on at least one sidewall.

14. The method of claim 13 , wherein the sidewalls are defined by protrusions extending away from the substrate.

15. The method of claim 13 , wherein the sidewall is defined by a cavity extending into the substrate.

16. 14. The method of claim 13, wherein the diamond layer is formed to continuously cover the surface of the substrate.

17. The method of claim 13 , wherein the diamond layer is formed to partially cover the surface of the substrate.

18. 14. The method of claim 13, wherein the diamond layer is formed to conformally cover the surface of the substrate.

19. 14. The method of claim 13, wherein the diamond layer is formed to thin or thicken by less than 20% across the surface of the substrate.

20. 14. The method of claim 13, wherein the diamond layer has a uniform thickness across a selected area of ​​the surface of the substrate.

21. 14. The method of claim 13, wherein the diamond layer is at least one of a plurality of diamond and non-diamond layers formed over at least a portion of a surface of the substrate.

22. 14. The method of claim 13, wherein the diamond layer on the surface and sidewalls is formed to have 50% of grains between 2 nanometers and 500 nanometers in size.

23. The method of claim 13 , wherein the substrate is opaque at optical wavelengths.

24. 14. The method of claim 13, wherein the diamond layer is deposited at less than 600°C.

25. 1. A wafer tool structure comprising: a wafer tool including a substrate having a surface including at least one sidewall; a diamond layer having a thickness between 10 nanometers and 1000 nanometers, the diamond layer being formed from diamond grains having a size that is 50% or less of the thickness of the diamond layer, and the diamond coating being deposited on a surface of a substrate on at least one sidewall.

26. 26. The structure of claim 25, wherein the sidewall is defined by a protrusion extending away from the substrate.

27. 26. The structure of claim 25, wherein the sidewall is defined by a cavity extending into the substrate.

28. 26. The structure of claim 25, wherein the diamond layer is formed continuously over the surface of the substrate.

29. 26. The structure of claim 25, wherein the diamond layer is formed to partially cover a surface of the substrate.

30. 26. The structure of claim 25, wherein the diamond layer is formed to conformally cover a surface of the substrate.

31. 26. The structure of claim 25, wherein the diamond layer is formed less than 20% thinner or thicker across the surface of the substrate.

32. 26. The structure of claim 25, wherein the diamond layer has a uniform thickness across a selected area of ​​the surface of the substrate.

33. 26. The structure of claim 25, wherein the diamond layer is at least one of a plurality of diamond and non-diamond layers formed over at least a portion of a surface of the substrate.

34. 26. The structure of claim 25, wherein the diamond layer on the surface and sidewalls is formed with 50% of the grains having a size between 2 nanometers and 500 nanometers.

35. 26. The structure of claim 25, wherein the substrate is opaque at optical wavelengths.

36. 26. The structure of claim 25, wherein the diamond layer is deposited at less than 600°C.

37. 1. A method for depositing a layer on a wafer tool, comprising: providing a wafer tool including a substrate having a surface further including at least one sidewall; and 1. A method of depositing a diamond layer having a thickness between 10 nanometers and 1000 nanometers, the diamond layer being formed from diamond grains having a size no greater than 50% of the thickness of the diamond layer, the diamond coating being deposited on the surface of the substrate on at least one sidewall.

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