Multi-layer diamond display system and method

Abstract

The multi-layer diamond system includes an optically transparent substrate and an optically transparent intermediate layer deposited on the optically transparent substrate, the diamond layer being formed from diamond having at least 50% diamond grains with a size between 2 nanometers and 500 nanometers.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. patent application Ser. No. 17 / 152,709, filed January 19, 2021, which is a divisional application of U.S. patent application Ser. No. 16 / 292,280, filed March 4, 2019, which is a divisional application of U.S. patent application Ser. No. 15 / 831,184, filed December 4, 2017, which claims the benefit of U.S. provisional patent application Ser. No. 62 / 429,769, filed December 3, 2016, the contents of which are incorporated herein by reference in their entireties.

[0002] The present invention relates to systems and methods for coating substrates with transparent diamond, and in particular to systems and methods for providing optically transparent multi-layer diamond systems suitable for displays, cover glasses, protective covers, or optical systems. [Background technology]

[0003] Diamond theoretically has good semiconductor performance characteristics, and there is potential for the fabrication of transparent electronic devices from diamond, including those related to consumer electronics materials such as displays and lens materials. These applications often require more stringent design requirements, such as improved hardness, scratch resistance, and water resistance. However, there are currently limited applications of semiconductor devices fabricated from diamond as consumer electronics materials. Summary of the Invention [Means for solving the problem]

[0004] Disclosed herein are new and improved systems and methods for multi-layer diamond display systems. According to one aspect of the present approach, a multi-layer diamond display system can include an optical-grade silicon substrate, a transparent substrate layer, a titanium dioxide transparent layer having a refractive index of 2.35 or greater, and a polycrystalline diamond layer, the transparent layer being disposed between the substrate layer and the polycrystalline diamond layer. In some embodiments, the diamond layer deposited on the optically transparent intermediate layer can be formed from diamond having at least 50% diamond grains between 2 nm and 1 micron in size.

[0005] In another approach, a method of manufacturing a multi-layer diamond display system may include the steps of selecting a substrate, forming a fused silica and titanium dioxide layer on the substrate, forming a fused silica layer on the fused silica and titanium dioxide layer, forming a transparent titanium dioxide layer on the fused silica layer, and forming a nanocrystalline diamond layer on the titanium dioxide layer.

[0006] In another embodiment, a multi-layer diamond system includes an optically transparent substrate and an optically transparent intermediate layer deposited on the optically transparent substrate. A diamond layer is deposited on the optically transparent intermediate layer and is formed from diamond having at least 50% of diamond grains with a size between 2 nm and 500 nm. Alternatively, a diamond layer can be deposited on the optically transparent intermediate layer, in which at least 50% of the diamond grains are microcrystalline grains with a size between 500 nm and 1 micron.

[0007] Other systems, methods, aspects, features, embodiments, and advantages of the systems and methods disclosed herein will become apparent to one of ordinary skill in the art upon examination of the following drawings and detailed description, and it is intended that all such additional systems, methods, aspects, features, embodiments, and advantages be included herein and be within the scope of the appended claims. [Brief explanation of the drawings]

[0008] It should be understood that the drawings are for illustrative purposes only. Additionally, the components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the systems disclosed herein. In the drawings, like reference numbers indicate corresponding parts throughout the different views. [Figure 1] FIG. 1 is an exemplary schematic diagram of a manufacturing process for a multi-layer diamond display system. [Figure 2] FIG. 2 is an exemplary block diagram of one embodiment of a method for manufacturing a multi-layer diamond display system, such as the display system of FIG. [Figure 3] FIG. 3 is a further exemplary schematic diagram of a manufacturing process for a multi-layer diamond display system. [Figure 4] FIG. 4 is a graph of a transmission spectrum that can be produced by the manufacturing processes described herein, such as those shown in FIGS. [Figure 5] FIG. 5 is a schematic representation of one embodiment of a multi-layer diamond system for display glass that can be produced by the manufacturing processes described herein, such as those shown in FIGS. [Figure 6] FIG. 6 is a table comparing prior art materials with systems that can be produced by the manufacturing processes described herein, such as the embodiment shown in FIG. [Figure 7] FIG. 7 is a schematic representation of another embodiment of a multi-layer diamond system having inner and outer diamond layers that can be produced by the manufacturing processes described herein, such as those illustrated in FIGS. [Figure 8] FIG. 8 is a schematic representation of another embodiment of a monolithically integrated diamond capacitance layer that can be fabricated by the fabrication processes described herein, such as those illustrated in FIGS. DETAILED DESCRIPTION OF THE INVENTION

[0009] In the following detailed description, one or more specific embodiments are described and illustrated by reference to and incorporation into the drawings. These embodiments are provided for purposes of illustration and teaching only, and are not intended to be limiting. These embodiments have been shown and described in sufficient detail to enable those skilled in the art to practice the claimed subject matter. Thus, for purposes of brevity, these descriptions may omit certain information known to those skilled in the art.

[0010] The systems and methods provided herein enable novel multilayer anti-reflective coating systems fabricated from diamond, as well as novel methods for infrared optical windows. Figure 1 shows an exemplary schematic diagram 100 of a manufacturing process for a multilayer diamond display system. The schematic diagram 100 includes a substrate material layer 102, a thin film composite layer 104, and a diamond layer 106. The substrate material layer 102 may include, but is not limited to, aluminosilicate glasses such as Corning Gorilla Glass® 3, commercially available glasses such as BK7, fused silica, quartz, sapphire, indium tin oxide, titanium dioxide such as, but not limited to, crystalline rutile, in addition to other materials known to those skilled in the art. Any of the above materials, or combinations thereof, may be included in the substrate material layer 102.

[0011] The thin film composite layer 104 can include a transparent material with a refractive index of 2.35 or greater. In one embodiment, titanium dioxide is deposited on the substrate layer 102 by, for example, but not limited to, physical vapor deposition (PVD) sputtering or reactive ion deposition. In some embodiments, the first thin film layer can have a refractive index in the range of 2.6 to 2.8. Crystalline titanium dioxide can be used to form the thin film composite layer 104. The thin film layer 104 includes a transparent material with a lower refractive index to increase transmittance in the blue, green, and red wavelength ranges. Materials optimized for operating wavelengths of 440 nm to 470 nm for blue light, 510 nm to 550 nm for green light, and 600 nm to 640 nm for red light can be used for the thin film composite layer 104.

[0012] The diamond layer 106 can be fabricated by a process including seeding with a nanocrystalline diamond mixed solution. The fabrication of the diamond layer 106 can include acid cleaning, such as piranha cleaning and ionic cleaning. The fabrication of the diamond layer 106 can include an ultrasonic roughening process to promote more uniform and strong aggregation of the growth diamond material. The fabrication of the diamond layer 106 can include, but is not limited to, chemical vapor deposition processes such as hot filament and microwave plasma. In one embodiment, nanocrystalline diamond material can be formed under vacuum conditions using methane, hydrogen, and argon gases.

[0013] 2 shows an exemplary block diagram of one embodiment of a method 200 for fabricating a multi-layer diamond system, such as, but not limited to, the display system of diagram 100. Method 200 includes step 202 of selecting a substrate material, such as an optical grade substrate, e.g., substrate material layer 102.

[0014] Method 200 includes depositing a thin film layer, such as, but not limited to, thin film composite layer 104. Method 200 includes a seeding cleaning step 206, in which the surface of the substrate is acid cleaned, for example, by piranha cleaning and ion cleaning, and ultrasonically roughened to promote more uniform and tight aggregation of the synthetic diamond material. In step 206, the substrate is seeded with a nanocrystalline diamond mixture solution.

[0015] Method 200 includes step 208 of exposing the substrate to a gas. Step 208 includes a substrate wafer cooling stage to maintain a temperature below 500°C, which allows for multilayer integration without exceeding the stress, softening, and distortion limits of the underlying material layers. Energy for diamond synthesis is substantially derived from a thermally activated filament source or a microwave activated plasma source. Method 200 includes step 210 of performing finishing processes on the multilayer diamond display system. Step 210 can include surface treatment, surface polishing, and packaging.

[0016] 3 shows another exemplary schematic 300 of a manufacturing process for a multi-layer diamond display system. Schematic 300 includes a substrate material layer 302, a first thin film composite layer 304, a fused silica layer 306, a titanium dioxide layer 308, and a diamond top layer 310. Substrate material layer 302 may include a transparent substrate such as those described in connection with substrate material layer 102.

[0017] The first thin film composite layer 304 may comprise fused silica and titanium dioxide, which has a refractive index of approximately 1.75. The titanium dioxide layer may have a refractive index ranging from 2.6 to 2.8, with a minimum of 2.35. The diamond top layer 310 may be formed in a manner similar to that described with respect to diamond layer 106.

[0018] Figure 4 shows a graph of a transmission spectrum 406 that can be produced by a manufacturing process described herein, such as the processes shown in Figures 2 and 3. Graph 400 includes a horizontal axis 402 that indicates the wavelength of light transmitted through a system fabricated according to the technique shown in Figure 3, and a vertical axis 402 that indicates the optical transmittance, the system including (a) a 44 nm fused silica / titanium oxide layer, such as first thin film composite layer 304; (b) a 186 nm fused silica layer, such as fused silica layer 306; (c) a 67 nm titanium dioxide layer, such as titanium dioxide layer 308; and (d) a 40 nm diamond top layer, such as diamond top layer 310. Spectrum 406 shows transmittances at the peak wavelengths of 89.7%, 86.2%, and 87.1% for the blue, green, and red wavelengths, respectively, for an overall transmittance of 88% to 89%. Such high transmittance is visually indistinguishable from the 92% transmittance currently specified for mobile and wearable displays (e.g., standard Corning Gorilla Glass®) in this wavelength range. By increasing the number of layers, transmittance can be increased beyond this value. By interspersing glass layers with other layers, the peak transmittance can be tuned to the desired visible wavelength.

[0019] FIG. 5 illustrates a schematic representation 500 of one embodiment of a multilayer diamond system for display glass that can be fabricated by the manufacturing processes described herein, such as those illustrated in FIGS. 1-3. The representative configuration 500 includes a rigid chassis layer 502, a flexible organic light-emitting diode layer 504, a capacitive touch layer 506, an inner lens glass layer 508, and an outer lens glass layer 510. The rigid chassis layer 502 can include, for example, aluminum. The capacitive touch layer 506 can include indium tin oxide and fused silica. The inner lens glass layer 508 can include Gorilla Glass. The outer glass lens layer 510 can be formed using the systems and methods illustrated in FIGS. 1 and 2. A diamond multilayer structure such as that illustrated in the schematic representation 500 can provide desirable strength and hardness properties, and its high thermal conductivity allows for operation at low thermal loads. These strength and hardness properties are shown in table 600 of FIG. 6, with the properties of the representative configuration 500 listed in the bottom row. In table 600, the nanocrystalline diamond is about 200 nanometers and the fused silica glass is about 500 microns.

[0020] Figure 7 is a schematic representative form 700 of another embodiment of a multi-layer diamond system that can be fabricated by the manufacturing processes described herein, such as those illustrated in Figures 1-3. Representative form 700 includes a rigid chassis layer 702, a flexible organic light emitting diode layer 704, a capacitive touch layer 706, and an outer lens glass layer 708. Representative form 700 can incorporate or eliminate an inner lens, such as the inner lens in representative form 500. Outer glass lens layer 708 can be formed by incorporating the systems and methods illustrated in Figures 1 and 2.

[0021] FIG. 8 is a schematic representation 800 of another embodiment of a monolithically integrated multilayer diamond system that can be fabricated by the fabrication processes described herein, such as those illustrated in FIGS. 1-3. The representation 800 includes a rigid chassis layer 802, a flexible organic light-emitting diode layer 804, and an outer glass lens layer 506. The outer glass lens layer 506 can be formed by incorporating the systems and methods illustrated in FIGS. 1 and 2. The representation 800 enables a multilayer diamond system of less than 0.5 millimeters. The representation 800 can incorporate a capacitive touch layer as a substrate layer. The representation 800 can provide a monolithically integrated multilayer diamond system module with mechanical, optical, and thermal tolerances that meet or exceed the requirements of display applications.

[0022] The above-described multi-layer diamond display system and method 200 may incorporate the systems and methods disclosed and described in U.S. Patent Application Publication No. 2013 / 0026492 to Adam Khan, published January 31, 2013; U.S. Patent No. 8,354,290 to Anirudha Sumant et al., published January 15, 2013; U.S. Patent No. 8,933,462 to Adam Khan, published January 13, 2015; U.S. Patent Application Publication No. 2015 / 0206749 to Adam Khan, published July 23, 2015; and U.S. Patent Application Publication No. 2015 / 0295134 to Adam Khan et al., published October 15, 2015, all of which are incorporated herein by reference in their entireties.

[0023] In some embodiments, single or multiple diamond films or layers 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 that achieve or enhance various applications or functions, such as light redirection, interference, cover glass, protective covers, displays, windows, chemical, thermal, or mechanical protection, etc. Applications or components using 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 electronics, manufacturing equipment, or tools. Other applications for multilayer diamond coatings include use in biological substrates and medical devices, and integration with batteries, fuel cells, electrochemical systems, chemical sensors, general-purpose sensing devices, or other advanced materials.

[0024] As used in this disclosure, the terms "layer," "film," and "coated" are used interchangeably and refer to a thinly deposited, chemically formed growth material or other suitable material on a substrate, which itself may be a layer, film, or coating. Diamond layers or films can include intrinsic diamond, diamond-like materials, or diamond containing small amounts of graphite or other materials. The lattice structure of diamond can be selectively modified, including varying the sp2 / sp3 carbon material configuration through selective seeding or etching, nucleation or growth process parameters, including, inter alia, parameters such as gas composition, pressure, and temperature, selective laser annealing, particle bombardment or doping, or the use of laser pulses to grow diamond. Further embodiments include modifying diamond layers or films through oxygen termination, hydrogen termination, or functionalization with chlorine or fluorine.

[0025] In some embodiments, doping, including p-type doping and n-type doping, is advantageous in diamond layers intended for sensing, waveguide, or electronic applications. Dopants may also be added, including, but not limited to, P, B, Li, or H. In some embodiments, the introduction of a minimal amount of acceptor-type dopant atoms into the diamond lattice can further form ion tracks. The formation of ion tracks can occur, for example, at a rate of 10 to 10 times the bulk volume of a single crystal. 22 / cm 3 This can include the creation of a non-critical concentration of vacancies below 100 K and a reduction in the breakdown voltage performance of the diamond layer. For example, acceptor-type dopant atoms can be introduced by ion implantation at approximately 80 Kelvin (K) to 600 K. In another embodiment, low concentrations of acceptor-type dopant atoms can be introduced by ion implantation at 293 to 298 K. The acceptor-type dopant atoms can be p-type acceptor-type dopant atoms. P-type dopants can be, but are not limited to, boron, hydrogen, and lithium. In one embodiment, ion tracks can be formed that act as ballistic pathways for introducing larger substitutional dopants. This allows the substitutional dopant atoms to be placed into the diamond lattice through the ion tracks. For example, ion implantation can be used to implant larger substitutional dopant atoms at temperatures of approximately 78 K or less with energies less than 500 keV. Implantation temperatures below 78 K maximize substitutional implantation of substitutional dopant atoms while freezing out vacancies and interstitials in the diamond lattice. The larger substitutional dopant atoms may be, for example, but not limited to, phosphorus, nitrogen, sulfur, and oxygen. Such larger substitutional dopant atoms can be introduced at much higher concentrations than acceptor-type dopants. The higher concentration of the larger substitutional dopant atoms is approximately 9.9×10 for phosphorus. 17 / cm 3 and 8×10 17 ~2×10 18 / cm3 As another example, for nitrogen, the range may be, but is not limited to, 9×10 18 / cm 3 It can be injected at a concentration of

[0026] In some embodiments, the diamond layer may have an sp2 concentration of less than 20% by volume. <111> or <100> In yet another embodiment, the highly oriented diamond film may have at least 80% grain orientation in any one of the crystal directions. <111> and <100> The crystal orientation may include different crystal orientations, with the crystal orientation of the first crystal orientation being predominant.

[0027] The properties of diamond in multilayer coating or film systems can be measured and evaluated 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 distinguished from a graphite or other carbon crystal background. Slight shifts in band wavenumbers can indicate the composition and properties of diamond. In some embodiments, the full width half maximum (FWHM) obtained from Raman characterization of diamond layers or films formed in accordance with the present disclosure may range from 5 to 15. In another embodiment, the diamond layer may have a Raman spectral characteristic of diamond (approximately 1332 nm) that is at least 0.5:1 or greater compared to the peak band of graphite (1400 nm to 1600 nm) by Raman analysis. In another embodiment, the diamond layer has a Raman spectroscopic characteristic of diamond (approximately 1332 nm) compared to the peak graphite band (1400 nm to 1600 nm) by Raman analysis of at least 0.5:1 or greater. In another embodiment, the diamond layer can have a physical property of a Vickers hardness of at least 12 gigapascals, or greater than 20 gigapascals, as measured by nanoindentation. In another embodiment, the diamond layer is measured to exert a compressive stress of less than 50 gigapascals.

[0028] 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 nanometers to 10 nanometers), nanocrystalline grain sizes (10 nanometers to 500 nanometers), or microcrystalline grain sizes (500 nanometers or greater). In some embodiments, the diamond grain size can include a range of grain sizes, from large to small. In some embodiments, the diamond layer can be formed with grains less than 1 micron. In some embodiments, the grain size can vary and be greater than or less than 50%, 100%, 200%, or 500% of the average grain size of the diamond. In other embodiments, the diamond grain size is maintained within 50%, 20%, or 10% of the average grain size. In some embodiments, 50%, 60%, 80%, or 90% of the diamond particles may have a size between 50 nanometers and 500 nanometers. In some embodiments, the diamond layer may be formed of at least 90% nanocrystalline diamond and have diamond particles with a size between 2 nanometers and 500 nanometers. In some embodiments, the diamond layer may be formed of at least 90% microcrystalline diamond and have diamond particles with a size between 500 nanometers and 1000 nanometers. In other embodiments, the diamond particles may be sized between 500 nanometers and 1000 nanometers. In other embodiments, 90% of the diamond particles may be sized between 200 nanometers and 300 nanometers.

[0029] In some embodiments, controlling the diamond grain size within the diamond layer can enhance certain optical, thermal, or mechanical properties of the diamond layer, including multilayer coating or film systems. For example, the use of ultrananocrystalline or nanocrystalline grains between 2 nanometers and 30 nanometers in size can enhance optical transparency.

[0030] In some embodiments, the thickness of the diamond layer can be selected from a range of 200 nanometers to 100 microns. Typically, the diamond grain size is 50% or less of the diamond layer thickness. In some embodiments useful for optical coatings, the diamond layer thickness ranges from 20 nanometers to 200 nanometers. For example, in one embodiment, glass or other transparent materials can be coated with a diamond film having a thickness of 10 nanometers to 1000 nanometers. When used in optical transmission systems, the diamond film provides optical transmittance through the glass substrate, with the diamond film having an optical transmittance 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 between 350 nanometers and 450 nanometers, and less than 0.60, 0.70, 0.80, or 0.90 at wavelengths between 750 nanometers and 850 nanometers. In another embodiment of the optical transmission system, the diamond film provides optical transmission through the glass substrate, having an optical transmission 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 to provide hazes 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 ultra-thin diamond layers (e.g., less than 200 nanometers). In another embodiment, coatings of thicker diamond layers up to 10 microns can be used to improve mechanical, frictional, or thermal properties.

[0031] The diamond layer may have a substantially uniform thickness across all or a particular portion of the surface or substrate. In other embodiments, the thickness may vary across portions of the surface or substrate. In some embodiments, the diamond layer may be conformal if it extends over cavities, recesses, or protrusions in the substrate or surface. In some embodiments, the diamond layer may gradually decrease or increase in thickness with distance from one or more locations on the substrate. In some embodiments, this decrease or increase in thickness may be less than 20%, less than 10%, less than 6%, or less than 3% of the thickness of the diamond layer on the substrate.

[0032] Multiple diamond layers differentiated by composition, crystal structure, dopant, grain size, or grain size distribution can be part of a multi-layer coating or film system applied to a substrate. The different diamond layers can be stacked on a diamond layer or a non-diamond material. In certain embodiments, the physical parameters of the diamond layer are continuously or semi-continuously variable vertically or laterally across the layer.

[0033] The diamond layer can be deposited and optionally structured using selective seeding techniques. The seed layer can include using selectively deposited or etched seed regions. In some embodiments, the nanocrystalline diamond can be deposited directly or in solution.

[0034] The diamond layer, whether grown with or without a seed, can be deposited on a variety of substrates, including but not limited to glass, ceramic, oxide, or metal. For example, the substrate may be a silicon oxide material, SiO2, fused silica, quartz, sapphire, gallium nitride (GaN), gallium arsenide (GaAs), or a refractory metal.

[0035] Furthermore, the carbon-carbon bonds in the substrate material allow for integration with other materials such as SiC, graphene, carbon nanotubes (CNTs), single-crystal and polycrystalline diamond materials, and combinations of these materials. They can be transparent, semi-transparent, or opaque at selected wavelengths or wavelength ranges. For example, in some embodiments, they can have a transmittance of 80% or greater at either optical or infrared wavelengths. In some embodiments, the diamond layer has a transparency of 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, 30 nanometers to 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, or about 150 nanometers (including all ranges and values ​​therebetween)). Furthermore, the diamond layer can have a root mean square (RMS) roughness of less than 7 nanometers. In some embodiments, the diamond layer can have a root mean square (RMS) roughness of less than 50%, less than 40%, less than 30%, less than 20%, or less than 10% of the film thickness. In some embodiments, the diamond layer can have a root mean square (RMS) roughness of less than 20%.

[0036] Diamond deposition can be accomplished by any process, including, but not limited to, chemical vapor deposition (CVD) or physical vapor deposition (PVD). A wide variety of deposition embodiments can be used. Examples of deposition processes include hot filament CVD, microwave CVD, RF-CVD, laser CVD (LCVD), laser ablation, conformal diamond coating processes, metal organic CVD (MOCVD), sputtering, thermal evaporation PVD, ionized metal PVD (IMPVD), electron beam PVD (EBPVD), reactive PVD, cathodic arc, and the like.

[0037] 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 be performed at temperatures between 300°C and 600°C. In other embodiments, deposition can be performed at temperatures between 375°C and 425°C. Compared to the 700°C to 800°C temperatures typically used for diamond film growth, these lower temperatures are advantageous in that they significantly reduce thermal effects, including thermal degradation and warpage, and allow for the use of a wider variety of substrates.

[0038] In some embodiments, various processes can be used to improve the quality of diamond or other films. For example, the substrate can undergo dry and / or wet chemical cleaning, 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 these cleaning processes. Plasma cleaning can include exposing the substrate to plasma generated from various concentrations of argon and / or oxygen. The ozone can be chemical ozone, ozone generated from a heat source, or both.

[0039] In some embodiments, prior to depositing the diamond or diamond-like film, the substrate may be treated by sputtering, evaporation, atomic layer deposition (ALD), chemical vapor deposition, plasma, thermal, or other deposition form of one or more materials, including, but not limited to, oxide and nitride dielectric materials, metal oxides such as titanium, indium, tin, zinc, or combinations thereof, graphene oxides such as graphene oxide, reduced fluorinated graphene oxide, oxides of silicon, titanium, or aluminum, nitrides of metals such as aluminum, silicon, titanium, boron, and tungsten or titanium. In some embodiments, this is advantageous because it reduces differences in thermal expansion coefficients, thereby reducing interlayer and subsurface stresses, allowing for color tuning as well as reducing optical losses due to haze or reflectivity.

[0040] In some embodiments, for metals deposited by sputter deposition, power levels can be adjusted and shutter open times can be varied to achieve a uniform target thickness across the display glass surface. For oxides and nitrides deposited by atomic layer deposition (ALD), low temperatures (including below 600°C) and / or crystalline structure can be utilized to achieve optimal integration of the thin film with the subsequent diamond layer.

[0041] In some embodiments, the substrate can be subjected to a surface functionalization process, including wet chemical surface functionalization, including spray coating, biased spray coating, ultrasonic spray coating, and volumetric changes caused by ultrasonic agitation of solvent and ketone mixtures (including, but not limited to, methanol, acetone, isopropyl alcohol, ethanol, butanol, and pentanol). The functionalized surface can include hydrocarbon chains, hydroxyl bonds, oxygen terminations, or other suitable chemically active materials.

[0042] To promote the growth of a diamond layer or film at selected particle sizes or in specific regions, a substrate can be seeded with diamond crystal particles 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 a positive, negative, or neutral zeta potential. The seed crystals can be present in a solvent, dimethyl sulfoxide, oil, photoresist, deionized water, combinations thereof, or similar types of suspensions or matrices. Substrate coverage with diamond crystal seeds can be uniform, non-uniform, or localized to selected areas using masks, selective spraying, electrospraying, ultrasonic spraying, or other spatially localized application methods. In some embodiments, seeds with different sizes and properties can be used.

[0043] The seed substrate can be loaded into a chemical vapor deposition (CVD) system under a low vacuum of 30 mTorr to 300 Torr. The chemical vapor deposition (CVD) system can be thermal, microwave, or a combination of thermal and microwave modes. Thermal chemical vapor deposition (CVD) can include a hot filament, a hot wire, a light beam, etc., while microwave chemical vapor deposition (CVD) can include either a 915 MHz or a 2.45 GHz system, or both. The substrate is then exposed to ions generated from a heat or microwave source. The ion source and reactant gases can include 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 used. The deposition process can be further modified by varying the pressure, applying a positive and / or negative bias to the stage, heating and / or cooling the stage, or controlling the distance between the stage and the plasma source. The volumes, ratios, and flow rates of the reactant and starting 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 to apply stress in the form of compressive rather than tensile forces to the grown diamond layer or film. In some embodiments, this allows the display glass layer to be held in compression, improving toughness and strength. Furthermore, the pyrolysis and ion energy of the source gases can improve diamond properties by controlling the volume of C₂H₂ hydrocarbon radicals versus C₂ (dimer) hydrocarbon radicals.

[0044] In some embodiments, the deposited diamond film can be further washed 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 oleophobicity without significantly reducing the diamond film's properties, including optical transmittance and / or hardness. In one embodiment, the graphene oxide can be obtained from a chemical suspension of multilayer graphene oxide, spin-coated onto the diamond film, and then wet- or dry-chemically (plasma-) reduced by including fluorine atoms in the material instead of oxygen.

[0045] In some embodiments, the diamond layer coating the substrate can be subjected to further chemical and mechanical treatments, such as reactive ion etching, to produce a planarized and uniform bulk diamond layer or film having a desired thickness. In one embodiment, the reactive ion etching (RIE) uses CHF3 and CF4 in a 3:1 ratio. Further planarization and / or polishing steps can be performed to achieve the desired flatness and surface finish.

[0046] The diamond layers or films described herein can be deposited on substrates of various types and shapes. The substrate can include Si, SiC, SiSiC, amorphous silicon, diamond-like carbon, metal-doped oxides, glass materials, polymeric materials, ceramics including quartz and sapphire, metals and metal alloys, or mixtures and combinations thereof. In some embodiments, the substrate can include aluminosilicate glass, such as Corning Gorilla Glass®, borosilicate glass, commercially available glass, such as BK7, fused silica, quartz, sapphire, indium tin oxide, titanium dioxide, such as, but not limited to, crystalline rutile.

[0047] In some embodiments, the shape and composition of the substrate can be modified by maskless etching, masked etching, additive or subtractive photoresist etching, or direct mechanical cutting, drilling, or grinding. In yet other embodiments, laser sintering or other additive manufacturing techniques can be used to build up the substrate into the desired shape. In some embodiments, doping, sputtering, evaporation, atomic layer deposition (ALD), chemical vapor deposition, plasma, thermal evaporation, or other deposition methods can be used to deposit the various materials described above in connection with the fabrication preparation of diamond layers or films. In some embodiments, the deposited diamond layer serves as a support for additional diamond or non-diamond layers or films.

[0048] In some embodiments, the substrate may have a flat, curved, or smoothly continuous shape and may include sidewalls, edges, chamfered edges, or curved edges. The surface may be of a single specific composition or may be of multiple compositions. Substrate embodiments may also include protrusions such as pillars and protrusions, along with single or multiple cavities, recesses, or channels defined therein. In other embodiments, the substrate may include burls, mesa-type features, 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, while in other embodiments, the size, spacing, and composition may be random or partially random.

[0049] The substrate is mechanically rigid and can have a thickness of a millimeter or more, although in some embodiments it includes another thin layer of diamond or a thin layer of metal, ceramic, glass, or other composition. These layers can be less than 1 millimeter, less than 1 micron, or less than 100 nanometers thick. Such layers can function as intermediate or buffer layers to improve the optical, electrical, thermal, or mechanical properties of the multilayer structure. In some embodiments, the substrate or intermediate layer is transparent and can include 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 include one or more of indium tin oxide, aluminum oxide, titanium oxide (including, but not limited to, titanium dioxide), magnesium oxide, silicon dioxide, and hafnium oxide. In other embodiments, the substrate or optically transparent intermediate layer can include one or more of aluminum, silicon, titanium, or boron nitride. The layer may also include, but is not limited to, a carbon film made of diamond-like carbon (DLC), amorphous carbon, or nano-crystalline diamond (NCD), a metal film made of molybdenum, titanium, tungsten, chromium, or copper, or a ceramic film made of SiC, TiC, CrC, WC, BN, B4C, Si3N4, TiN, CrN, SiCN, or BCN. When the thickness of the diamond film is in the range of 10 nanometers to 1000 nanometers, the thickness of the intermediate layer or buffer layer can be in the range of 10 nanometers to 100 microns.

[0050] The diamond layers, substrates, and thin films of non-diamond materials described above may include a variety of embodiments, properties, and combinations, including, but not limited to, the following examples: [Example]

[0051] In a first example, a transparent diamond layer can be continuously and conformally coated onto a transparent glass substrate to serve as an optically transparent protective coating suitable for smartphones, tablets, or laptops. For example, a nanocrystalline diamond film having a grain size ranging from 20 nanometers to 70 nanometers and a substantially uniform thickness of 70 nanometers to 110 nanometers can be deposited on an indium tin oxide (ITO) film deposited on a transparent glass substrate. A hydrophobic coating, or an additional doped or functionalized diamond coating, can be deposited on the nanocrystalline diamond film with a substantially uniform thickness of 70 nanometers to 110 nanometers to support a hydrophobic or oleophobic coating. In some embodiments, the grain size of the diamond particles can range from 5 nanometers 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 embodiments, the glass surface can be functionalized by introducing hydrocarbon chains onto the glass surface, resulting from the decomposition of the solvent during drying.

[0052] Conventional HF CVD reactors can be used with tungsten, tantalum, or rhenium filaments. The diameter, spacing, and number of filaments can be adjusted to achieve optimal results. In one embodiment, the filament diameter can be 0.12 mm to 0.5 mm, the spacing can be 8 mm to 30 mm, and 7 to 28 filaments can be used. The chamber can be spherical, rectangular, or cylindrical. In one embodiment, the cylindrical sphere can be sized to have a volume of 100 liters to 200 liters and a diameter of 30 centimeters to 150 centimeters.

[0053] The reactor may include stages to assist in heating or cooling the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature of 500°C to 600°C. At this temperature range, the deposition rate of the diamond layer is 10 to 100 nanometers per hour.

[0054] Precursor gases such as methane, hydrogen, oxygen, and argon can be introduced into the chamber at pressures of 10 to 15 Torr. Adding 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 0.5 to 5% of the total gas volume. The hydrogen concentration can be 60 to 90% of the total gas volume. The argon concentration can be 10 to 40% of the total gas volume.

[0055] To ensure uniform particle size, the substrate can be coated with diamond seeds dispersed in dimethyl sulfoxide (DMSO) or other solvent solutions including ethanol, methanol, IPA, and acetone. In some embodiments, particle sizes between 5 nanometers and 50 nanometers can be used.

[0056] In some embodiments, the diamond film is formed continuously and conformally over the substrate.

[0057] Furthermore, the diamond film has a full width at half maximum (FWHM) of 5-7, an sp2 concentration of less than 20% by volume, <111> The diamond film may have at least 80% grain orientation in the crystallographic direction, a diamond Raman spectrum (approximately 1332 nm) of 0.7:1 to 1.2:1 when compared to the peak graphite band (1400 nm to 1600 nm), and a Vickers hardness of 20 to 60 gigapascals. The transmittance of light at a wavelength of 550 nanometers through the glass substrate and diamond film is greater than 0.70, and the haze is less than 5%. [Example]

[0058] In a second example, a substrate can be coated with a nanocrystalline diamond layer or film having a grain size in the range of 100 nanometers to 2000 nanometers and a substantially uniform thickness of 100 nanometers to 2000 nanometers. In one embodiment, this 100 nanometer to 2000 nanometer thick nanocrystalline diamond film can be further etched and additional layers or films selectively applied to fill the etched diamond and support the formation of waveguides for data transmission. In some embodiments, the deposited grain size can include diamond grains in the range of 5 nanometers to 50 nanometers.

[0059] The reactor may include stages to assist in heating or cooling the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature of 500°C to 800°C. In this temperature range, the deposition rate of the diamond layer is between 10 nanometers and 200 nanometers per hour.

[0060] Substrates 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 between 5 nanometers and 15,000 nanometers can be used, with larger particle sizes typically being reduced in size by sonication or other processing steps. In some embodiments, various particle sizes or particle size ranges can be used, including co-deposition of small and large particle sizes. In some embodiments, the seeds are deposited so that the film is continuous and conformal across the substrate.

[0061] In some embodiments, the diamond layer or film may have a Young's modulus greater than 80 gigapascals. [Example]

[0062] In a third example, a transparent substrate can be coated with multiple layers, including diamond, ceramic, or metal layers. In some embodiments, a nanocrystalline diamond layer or film can be deposited having a grain size in the range of 5 nanometers to 50 nanometers and a substantially uniform thickness of 5 nanometers to 50 nanometers.

[0063] The reactor may include stages to assist in heating or cooling the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature of 500°C to 600°C. At this temperature range, the deposition rate of the diamond layer is 10 to 100 nanometers per hour.

[0064] In the foregoing description, reference has been made to the accompanying drawings that form a part hereof, and in which is 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 will be understood that changes can be made in 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.

[0065] References throughout this specification to "one embodiment," "an embodiment," "one example," or "example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases "in one embodiment," "in an embodiment," "one example," or "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 combination and / or subcombination in one or more embodiments or examples. It should also be noted that the drawings provided herein are for illustrative purposes to persons skilled in the art and are not necessarily drawn to scale.

[0066] It is anticipated that one skilled in the art will be able to contemplate various modifications and other embodiments of the present invention based on the teachings presented in the above description and its associated drawings. It is therefore to be understood that the present invention is not limited to the particular embodiments disclosed, but is intended to cover modifications and embodiments falling within the scope of the appended claims. It is also to be understood that other embodiments of the present invention may be practiced even if they do not include elements / steps not specifically disclosed herein.

Claims

1. 1. A multi-layer diamond system comprising: an optically transparent substrate; an optically transparent intermediate layer deposited on the optically transparent substrate; a diamond layer deposited on the optically transparent intermediate layer, the diamond layer being formed from diamond having at least 50% diamond grains having a size between 2 nanometers and 500 nanometers; A multi-layer diamond system having

2. 10. The multi-layer diamond system of claim 1, wherein the substrate is at least one of silicon oxide, glass, quartz, and sapphire.

3. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer is metal.

4. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer is ceramic.

5. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer is glass.

6. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer comprises at least one of tungsten and titanium.

7. 2. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer comprises indium tin oxide, aluminum oxide, titanium oxide including, but not limited to, titanium dioxide, magnesium oxide, silicon dioxide, and hafnium oxide.

8. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer comprises a nitride of aluminum, silicon, titanium, or boron.

9. 10. The multi-layer diamond system of claim 1, wherein at least one of the substrate and the transparent intermediate layer comprises at least one of an aluminosilicate glass and a borosilicate glass.

10. 2. The multi-layer diamond system of claim 1, wherein the diamond layer has a diamond film of substantially uniform thickness between 70 nanometers and 150 nanometers, the diamond film having at least 50% diamond grains of a size between 10 nanometers and 100 nanometers.

11. 10. The multi-layer diamond system of claim 1, wherein the substrate has a dimension of at least 1 centimeter.

12. 10. The multi-layer diamond system of claim 1, wherein the substrate further comprises: A multi-layer diamond system having a sidewall coated with said diamond layer.

13. 10. The multi-layer diamond system of claim 1, wherein the diamond layer is deposited on the substrate at a temperature less than 600°C.

14. 2. The multi-layer diamond system of claim 1, wherein the transmittance of light transmitted through the optically transparent substrate layer, the diamond layer, and the optically transparent intermediate layer at a wavelength of 550 nanometers is greater than 0.

80.

15. 1. A method of manufacturing a multi-layer diamond system, comprising: providing an optically transparent substrate; depositing an optically transparent intermediate layer on the optically transparent substrate; depositing a diamond layer on the optically transparent intermediate layer, the diamond layer being formed from diamond having at least 50% diamond grains between 2 nanometers and 500 nanometers in size; 1. A method for manufacturing a multi-layer diamond system, comprising:

16. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein the substrate is at least one of silicon oxide, glass, quartz, and sapphire.

17. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer is metal.

18. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer is ceramic.

19. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer is glass.

20. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer comprises at least one of tungsten and titanium.

21. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer comprises indium tin oxide, aluminum oxide, titanium oxide including but not limited to titanium dioxide, magnesium oxide, silicon dioxide and hafnium oxide.

22. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer comprises a nitride of aluminum, silicon, titanium, or boron.

23. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein at least one of the substrate and the transparent intermediate layer comprises at least one of an aluminosilicate glass and a borosilicate glass.

24. 16. A method for producing a multi-layer diamond system according to claim 15, wherein the diamond layer has a diamond film of substantially uniform thickness between 70 nanometers and 150 nanometers, the diamond film having at least 50% diamond grains of a size between 10 nanometers and 100 nanometers.

25. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein the substrate has a dimension of at least 1 centimeter.

26. 16. The method of manufacturing a multi-layer diamond system according to claim 15, wherein the substrate further comprises: A method for manufacturing a multi-layer diamond system having sidewalls coated with said diamond layer.

27. 16. A method of manufacturing a multi-layer diamond system according to claim 15, wherein the diamond layer is deposited on the substrate at a temperature of less than 600°C.

28. 16. A method for producing a multi-layer diamond system according to claim 15, wherein the transmittance of light transmitted through the optically transparent substrate layer, the diamond layer, and the optically transparent intermediate layer at a wavelength of 550 nanometers is greater than 0.80.

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