Glass modification process usable with CVD diamond deposition

Abstract

A diamond system includes a glass substrate having a first side and a second side, where the second side is chemically modified by ion substitution. The CVD deposited diamond layer may be present on the first side or another side or edge.

Description

Related applications

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 434,262, filed on December 21, 2022, which is hereby incorporated by reference in its entirety. Field of the Invention

[0002] The present invention generally relates to systems and methods for diamond coating chemically modified or ion-substituted glass using chemical vapor deposition (CVD). Typically, before or after diamond deposition, at least one side of a transparent glass substrate is chemically modified to increase the hardness and durability of the glass. background

[0003] Diamond films or coatings can be used to protect optical systems, as coatings for consumer applications (such as smartphone or watch displays), as coatings for tools or mechanical components, as coatings for chemical protection, or for electrical or semiconductor applications. Advantageously, diamond films provide increased hardness, scratch resistance, water resistance, and a variety of unique electrical properties. However, commercially practical diamond films or coatings remain limited due to the cost and time required to deposit usefully thick diamond coatings on glass substrates.

[0004] Another issue with diamond coatings on glass substrates arises from CVD thermal processing of chemically modified glass. To increase durability and reduce the chance of breakage, the glass can be chemically modified by immersion in a salt bath. For example, the glass can be immersed in a potassium nitrate bath at a temperature greater than 300°C. Sodium ions present on the surface of the glass are replaced by potassium ions from the bath. Since potassium ions are larger than sodium ions, the sodium ion replacement introduces large stresses to the surface of the glass, thereby protecting the glass from breakage, scratches, and thermal shock. As another example, aluminosilicate glass containing aluminum oxide levels between 20% and 40% can be processed in a molten salt solution at approximately 400°C. Again, the smaller sodium ions can be exchanged for larger potassium ions, providing greater surface strength.

[0005] Unfortunately, reheating the chemically modified glass in a CVD chamber for diamond deposition can cause potassium or other ions to diffuse from the glass surface throughout the glass, eliminating or reducing the chemical modification of the glass surface. What is needed are glass structures and processing techniques that provide or allow for chemically modified glasses with deposited diamond coatings. Overview

[0006] Disclosed herein are new and improved systems and methods for diamond coating using a CVD system. In some embodiments, a diamond-coated glass structure may include a glass substrate having a first side and a second side, wherein the second side is chemically modified by ion substitution. A CVD-deposited diamond layer may be provided on the first side.

[0007] In some embodiments, the CVD-deposited diamond layer contains less than 20% sp2 carbon.

[0008] In some embodiments, the CVD-deposited diamond layer includes multiple diamond layers.

[0009] In some embodiments, the CVD-deposited diamond layer includes an ultra-nanocrystalline diamond layer on a nanocrystalline diamond layer.

[0010] In some embodiments, the substrate has a dimension of at least one centimeter.

[0011] In some embodiments, ion substitution further comprises replacing at least some of the sodium ions with potassium ions.

[0012] In some embodiments, ion replacement further comprises replacing at least some of the ions on the second side to a penetration depth of less than 100 microns.

[0013] In some embodiments, a diamond-coated glass structure may include a glass substrate having a first side and a second side, wherein the first side and the second side are chemically modified by ion substitution and the penetration depth between the first side and the second side is different. A CVD-deposited diamond layer may be provided on at least one of the first side and the second side.

[0014] In some embodiments, a diamond-coated glass structure may include a glass substrate having opposing first and second sides and four edges, wherein the first and second sides and the four edges are chemically modified by ion substitution, and wherein the first side has a different penetration depth than the second side and at least one of the four edges. A CVD-deposited diamond layer may be provided on the first side.

[0015] In some embodiments, a method of making a diamond-coated glass structure may include providing a glass substrate having a first side and a second side, CVD depositing a diamond layer on the first side, and chemically modifying the second side by ion substitution after the CVD diamond deposition.

[0016] In some embodiments, a method of making a diamond-coated glass structure may include providing a glass substrate having a first side and a second side. The first side and the second side may be chemically modified by ion substitution. After chemically modifying the first side and the second side, a CVD diamond layer may be deposited on the first side.

[0017] In some embodiments, a method of making a diamond-clad glass structure may include providing a glass substrate having a first side and a second side.

[0018] A first chemical modification is performed on the first and second sides of the glass substrate by ion substitution, and a diamond layer may be deposited by CVD on the first side. After the CVD diamond deposition, a second chemical modification is performed on both the first and second sides of the glass substrate by ion substitution. In some embodiments, only the second side is chemically modified by ion substitution.

[0019] Other systems, methods, aspects, features, embodiments and advantages of the systems and methods disclosed herein will be or will become apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, aspects, features, embodiments and advantages be included within this description and be within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] It should be understood that the drawings are for illustrative purposes only. In addition, the components in the drawings are not necessarily drawn to scale, but emphasis is placed on illustrating the principles of the system disclosed herein. In the drawings, the same reference numerals indicate corresponding parts throughout the different views.

[0021] Figure 1A is an exemplary schematic diagram of a glass substrate that is coated with diamond on one side and then treated to chemically modify the side or edge that is not coated with diamond; Figure 1B is an exemplary schematic diagram of a glass substrate that is chemically modified and then at least partially coated with diamond; Figure 1C is an exemplary schematic diagram of a glass substrate that is optionally chemically modified, then at least partially coated with diamond, and then further processed to chemically modify the sides or edges that have been coated with diamond; Figure 1D is an exemplary schematic diagram of a chemically modified glass substrate having opposing top and bottom sides and four edges; Figure 1E is an exemplary graph indicating the penetration depth of substitutional ions into a glass substrate; Figure 2A It is used to make chemically modified glass coated with diamond on one side (such as Figure 1A An exemplary block diagram of an embodiment of the method of FIG. Figure 2B It is used to make chemically modified glass coated with diamond on one side (such as Figure 1Ban exemplary block diagram of an embodiment of the method of FIG. Figure 2C is used to make chemically modified glass coated with diamond on at least one side (such as Figure 1C An exemplary block diagram of an implementation of the method of FIG. Details

[0022] The following detailed description, with reference to and in conjunction with the accompanying drawings, describes and illustrates one or more specific embodiments. These embodiments are not intended to be limiting, but are provided merely for purposes of illustration and instruction, and are shown and described in sufficient detail to enable those skilled in the art to practice what is claimed. Therefore, for the sake of brevity, the description may omit certain information known to those skilled in the art.

[0023] As used in this disclosure, the terms "layer," "film," and "coated" are used interchangeably and refer to a thin deposited, chemically formed, grown material or otherwise located on a substrate, which itself may be a layer, film, or coating. The diamond layer or film may comprise intrinsic diamond, diamond-like material, or diamond with a small amount of graphite or other material. The diamond lattice structure may be selectively modified and may include providing different sp2 / sp3 carbon materials positioned by selective seeding or etching, nucleation or growth process parameters (including gas composition, pressure and temperature and other parameters), selective laser annealing, particle bombardment or doping, or the use of laser pulses to grow diamond. Modification of the diamond layer or film by oxygen termination, hydrogen termination, chlorine, or fluorine functionalization is an additional embodiment.

[0024] The diamond structures and manufacturing methods described herein may be incorporated into systems and methods previously disclosed and described in: U.S. Patent Publication No. 2013 / 0026492 to Adam Khan, published on January 31, 2013; U.S. Patent No. 8,354,290 to Anirudha Sumant et al., issued on January 15, 2013; U.S. Patent No. 8,933,462 to Adam Khan, issued on January 13, 2015; U.S. Patent Publication No. 2015 / 0206749 to Adam Khan, published on July 23, 2015; and U.S. Patent Publication No. 2015 / 0295134 to Adam Khan et al., published on October 15, 2015, all of which are incorporated herein by reference in their entirety.

[0025] In one embodiment, the chemical modification may include subjecting the diamond coated glass to an ion exchange process. As used herein, the terms "ion exchange" or "ion substitution" should be understood to mean that the glass is capable of being chemically modified by ion exchange processes known to those skilled in the art. Such ion exchange processes include, but are not limited to, treating the glass with a solution containing ions having an ionic radius greater than the ionic radius of ions present in the surface of the glass, replacing the smaller ions with the larger ions. In one embodiment of the process, at least some of the ions of a first element in a surface region of the glass article are exchanged with ions of a second element, wherein each of the ions of the second element has an ionic radius greater than the ionic radius of the ions of the first element being replaced. In one embodiment, the first element and the second element are alkali metals. Potassium (K + ions) replace sodium (Na + ions) are non-limiting examples of such ion exchange. Alternatively, other alkali metal ions with larger atomic radii, such as rubidium or cesium, can replace smaller alkali metal ions in the glass. In another embodiment, smaller alkali metal ions can be replaced by silver (Ag + ) ion replacement. In some embodiments, additional elements such as Li + , Rb + 、Cs + 、Cd 2+ 、Zn 2+ or Cu + / Cu 2+ As will be appreciated, ion exchange can be performed before or after diamond coating, and multiple ion exchange events can occur during glass processing.

[0026] Ion exchange can be carried out using those methods known in the art and described herein. Depending on the ion penetration depth and other characteristics, the chemical modification carried out by the ion exchange of the glass substrate can result in glass strengthening, hardening, or both. In one embodiment, the glass is immersed in a molten salt bath comprising an alkali metal salt such as, for example, potassium nitrate (KNO ) for a predetermined period of time to achieve ion exchange. In some embodiments, the glass substrate can be chemically modified in a single ion exchange step. In some embodiments, the glass substrate is immersed in a molten salt bath comprising a salt of a larger alkali metal cation. In some embodiments, the molten salt bath comprises a salt of a larger alkali metal cation or is substantially composed of a salt of a larger alkali metal cation. In some embodiments, a single ion exchange process can be carried out at a temperature lower than 600° C., while in other embodiments, the temperature can be between 275° C. and 550° C. for a time sufficient to achieve the desired ion penetration depth (in some embodiments, the penetration depth can increase with the increase of the glass thickness, and in some embodiments can be between 5 microns and 300 microns).

[0027] In another embodiment, the glass substrate can be chemically modified in a two-step or dual ion exchange process. In the first step of this process embodiment, the glass substrate is ion exchanged in a first molten salt bath. After the first ion exchange is complete, the glass can optionally be coated with diamond and then immersed in another ion exchange bath (e.g., a second ion exchange bath). The additional or second ion exchange bath can have the same composition as the first ion exchange bath. Alternatively, the additional or second ion exchange bath can have a different composition than the first ion exchange bath and / or be operated at a different immersion time length and temperature than the first ion exchange bath.

[0028] As about Figure 1A As shown, the systems and methods provided herein allow for the fabrication of a partially diamond-encapsulated glass structure 100A. The glass structure 100A includes a glass substrate 110A having a first side 112A, a second side 114A, and an edge 116A. In one embodiment, the second side 114A and the edge 116A are chemically modified by ionic substitution, wherein substantial substitution occurs along the second side 114A and the edge 116A to a depth of less than 100 microns. Figure 1A ion penetration region 120A. Advantageously, chemical modification of the glass substrate 110A can occur after depositing the diamond layer 130A on the first side 112A. Depending on the ion penetration depth and other characteristics, chemical modification by ion substitution of the glass structure can result in glass strengthening, hardening, or both.

[0029] In About Figure 1B In another embodiment shown in the figures, the systems and methods provided herein allow for the fabrication of a partially diamond-encapsulated glass structure 100B. The glass structure 100B includes a glass substrate 110B having a first side 112B, a second side 114B, and an edge 116B. In one embodiment, the first side 112B, the second side 114B, and the edge 116B are chemically modified by ionic substitution, wherein the substitution occurs substantially to a depth of less than 100 microns along the first side 112B, the second side 114B, and the edge 116B. Figure 1B 14B. In this embodiment, chemical modification of the glass substrate 110B can occur prior to depositing the diamond layer 130B on the first side 112B. Due to the potential for ion motion under the thermal conditions required for diamond deposition, the depth of the ion penetration region 120B will vary significantly between the first side 112B and the second side 114B. In some embodiments, variations in ion concentration or ion depth in the ion penetration region 120B on the second side 114B can be limited by contacting the second side 114B with a cooling tool during diamond deposition.

[0030] Figure 1Cis an exemplary schematic diagram of a glass substrate that is optionally chemically modified, then at least partially coated with diamond, and then further processed to chemically modify the sides or edges that have been coated with diamond. Glass structure 100C includes a glass substrate 110C having a first side 112C, a second side 114C, and an edge 116C. In one embodiment, first side 112C, second side 114C, and edge 116C are chemically modified by ionic substitution, wherein substantial substitution occurs along first side 112C, second side 114C, and edge 116C to a depth of less than 100 microns, with the thickness of the glass substrate 100C being less than 100 microns. Figure 1C Indicated as ion penetration region 120C in the figure. In this embodiment, chemical modification of the glass substrate 110C can occur before depositing the diamond layer 130C on the first side 112C. Due to the possible ion movement under the thermal conditions required for diamond deposition, the depth of the ion penetration region 120C will be significantly different between the first side 112C and the second side 114C. In some embodiments, the change in ion concentration or ion depth in the ion penetration region 120C on the second side 114C can be limited by contacting the second side 114C with a cooling tool during diamond deposition. Alternatively or additionally, after depositing the diamond layer 130C, the glass structure 100C can be placed in a second or multiple ion exchange baths for further chemical modification. In some embodiments, chemical modification by dopant implantation through the diamond layer 130C can be used to increase the ion concentration or penetration below the diamond layer 130C.

[0031] Figure 1D FIG1 is an exemplary schematic diagram of a chemically modified glass substrate 110C having opposing top and bottom sides and four edges with corners. After ion exchange for chemical modification, the regions between the penetration depth 105D (indicated by dashed lines) and the corresponding top, bottom, edges, and corners are chemically modified.

[0032] Figure 1E is an exemplary graph 100E indicating a penetration depth 105E for ion substitution into a glass substrate having a top diamond cladding layer, such as with respect to Figure 1A-1D In one embodiment, the ion exchange results in a penetration profile of an ion exchange surface layer at the top, bottom, or edge of the glass substrate to a depth of at least 20 microns in the glass. In alternative embodiments, the penetration depth into the glass is at least 5 microns, 10 microns, 20 microns, 30 microns, or 50 microns. Figure 1B and Figure 1C It is clear from the discussion that the depth of ion penetration is different depending on the presence or absence of a diamond layer. In this embodiment, ion penetration through the top layer with a diamond coating is significantly less than edge or bottom penetration.

[0033] Figure 2A It is used to make chemically modified glass substrate structures coated with diamond on one side (such as Figure 1A 2 is an exemplary block diagram of an embodiment of a method of manufacturing a glass substrate structure (as illustrated). In this embodiment, in a first step 210A, CVD diamond is formed on at least a first side. The first side can be one of the top, bottom, edge or corner. In addition to the first side, in some embodiments, an additional second side, a third side, etc. can be coated with CVD diamond. In step 212A, ion substitution is used to chemically modify at least a second side of the glass substrate structure. The second side can be one of the top, bottom, edge or corner. In step 214A, one or more processing steps that can include optional additional laminate materials (e.g., organic coatings, polymer coatings, inorganic coatings or graphene coatings) can be applied to at least one of the chemically modified glass substrate structures at the top, bottom, edge or corner.

[0034] Figure 2B It is used to make chemically modified glass substrate structures coated with diamond on one side (such as Figure 1B 2 is an exemplary block diagram of an embodiment of a method of manufacturing a glass substrate structure (as illustrated). In this embodiment, in a first step 212B, ion substitution is used to chemically modify at least a first side and a second side of a glass substrate structure. The second side can be one of the top, bottom, edge, or corner. In step 212B, CVD diamond is formed on at least the first side. The first side can be one of the top, bottom, edge, or corner. In addition to the first side, in some embodiments, an additional second side, a third side, etc. can be coated with CVD diamond. In step 214B, one or more processing steps that may include optional additional laminate materials (e.g., an organic coating, a polymer coating, an inorganic coating, or a graphene coating) can be applied to at least one of the chemically modified glass substrate structures at the top, bottom, edge, or corner.

[0035] Figure 2C It is used to make a C structure with diamond coating on at least one side (such as Figure 1C) is an exemplary block diagram of an embodiment of a method of (as illustrated). In this embodiment, in a first step 212C, ion substitution is used to chemically modify at least a first side and a second side of a glass substrate structure. The second side can be one of the top, bottom, edge, or corner. In step 212C, CVD diamond is formed on at least the first side. The first side can be one of the top, bottom, edge, or corner. In addition to the first side, in some embodiments, another second side, a third side, etc. can be coated with CVD diamond. In step 214C, the chemically modified glass substrate structure can be placed in a second or more ion exchange baths for further chemical modification. In some embodiments, chemical modification by dopant implantation through the CVD deposited diamond layer can be used to increase the ion concentration or penetration below the diamond. In step 216C, one or more processing steps that may include optional additional laminate materials (e.g., organic coatings, polymer coatings, inorganic coatings, or graphene coatings) can be applied to at least one of the chemically modified glass substrate structures at the top, bottom, edge, or corner.

[0036] As will be appreciated, various types of glass substrates may be used in the structures. For example, the glass may be a silicate glass, such as alkali silicate glass, soda lime glass, alkali aluminosilicate glass, aluminosilicate glass, borosilicate glass, alkali aluminogermanate glass, alkali germanate glass, alkali gallium germanate glass, and combinations thereof. The structures may also be fabricated on infrared (IR) substrate materials including, but not limited to, silicon (Si), zinc sulfide (ZnS), zinc selenide (ZnSe), germanium (Ge), magnesium fluoride (MgF2), sapphire (Al2O3), aluminum oxynitride (Al2O3), and the like. x O y N z ), spinel (MgAl2O4), calcium fluoride (CaF2), sodium chloride (NaCl). In some embodiments, multiple types of glass or IR materials can be fused or laminated together to provide a substrate. Other examples of suitable glass types and compositions are more fully described in U.S. Patent 8,232,218 assigned to Corning, Inc.

[0037] The glass substrate may be less than 5 mm thick, and in some embodiments, may be between 0.5 mm and 3 mm thick. In particularly thin embodiments, the glass substrate may be between 0.3 mm and 1 mm thick. In some embodiments, the glass substrate may be between 0.25 mm and 3 mm thick. In other embodiments, the thickness may be less than 2 mm, less than 1 mm, or less than 0.6 mm.

[0038] In one embodiment, forming the edge of the glass substrate to correspond to a specific predetermined geometry and providing a chemical modification can result in increased compression near the edge of the glass cover. Thus, by applying a specific predetermined geometry to the edge of the glass cover, the glass cover can be made stronger. In one embodiment, the surface (e.g., the edge) of the glass cover can be chemically modified. In one embodiment, the edge geometry is configured to reduce or smooth sharp transitions, such as corners.

[0039] In some embodiments, one or more edges of the glass substrate may be curved or chamfered. A chamfer is a beveled edge that substantially connects two sides or surfaces (e.g., a top surface and a bottom surface). As an example, the edge geometry may include a chamfered edge between 0.2 mm and 0.5 mm that extends at least partially between the top and bottom sides of the glass substrate. Advantageously, the use of chamfered edges can reduce compressive stress. Alternatively or additionally, in one embodiment, the glass substrate edge may include a smooth corner, wherein, for example, the corner between the first surface and the second surface (e.g., a top surface / bottom surface and a substantially vertical side surface) may be made less sharp. As another example, the transition between the top surface and the side surface or between the bottom surface and the side surface may be smooth. In some embodiments, the edge of the glass may be rounded by a predetermined edge geometry having a predetermined edge radius (or predetermined curvature) of at least 10% of the thickness of the corner applied to the edge of the glass. In other embodiments, the predetermined edge radius may be between 20% and 50% of the thickness of the glass. In one embodiment, the glass cover can extend to the edge of the housing of the electronic device without a protective bezel or other barrier. In one embodiment, the glass cover can include a bezel around the corresponding edge. The glass cover can be disposed on or integrated with a display, such as a liquid crystal display (LCD) display that can be used in a smartphone, watch, or tablet computer.

[0040] In some embodiments, the glass substrate structure can undergo optional processing steps. Such processing steps can include applying one or more additional coating layers or laminates (e.g., organic, polymeric, inorganic, or graphene) to the glass substrate. In some embodiments, the entire substrate can have additional coating layers, while in other embodiments, at least one of the top, bottom, edge, or corner of the glass substrate can be provided with a coating layer.

[0041] In some embodiments, prior to depositing the diamond or diamond-like coating or film, the substrate may be treated by sputtering, evaporation, atomic layer deposition (ALD), chemical vapor deposition, plasma, or thermal deposition of one or more materials, including but not limited to oxide and nitride dielectric materials, oxides of metals such as titanium, indium, tin, zinc, or combinations thereof, oxides of graphene such as graphene oxide, reduced fluorinated graphene oxide, oxides of silicon, titanium, or aluminum, oxynitrides and nitrides of aluminum, silicon, titanium, and boron, and metals such as tungsten or titanium. These intermediate materials can enable or enhance: 1) adhesion of subsequent layers, 2) system optical properties such as transmission and reflection, 3) system stress caused by enhanced transitions in thermal coefficients, 4) reduced surface roughness, and other properties. In some embodiments, for metals deposited via sputter deposition, the power level can be adjusted and the shutter open time can be varied to achieve a target thickness uniformly across the display glass surface. For oxides and nitrides, thin films can utilize lower temperatures (including temperatures less than or equal to 600°C). Advantageously, in some embodiments, this can reduce differences in coefficient of thermal expansion, reduce interlayer and subsurface stresses, and allow for tuning of chromaticity and visual uniformity as well as optical losses attributable to haze or reflectivity.

[0042] In order to promote the growth of diamond layers or films with selected grain sizes or in a limited area, the substrate can be seeded with diamond crystal particles. The seed layer can be formed by using a seed region of selective deposition or etching. In some embodiments, nanocrystalline diamond can be deposited directly or in a solution. In some embodiments, the seed size can be in the range of 5 nanometers to 50 nanometers. The seed can be functionalized, or can have a positive zeta potential, a negative zeta potential, or a neutral zeta potential. The seed crystal can be in a combination or similar type of solvent, dimethyl sulfoxide, oil, photoresist, deionized water, a suspension, or a matrix. Using a mask, selective spraying, electrospraying, ultrasonic spraying, ultrasonic processing, or other forms of spatial local application, the substrate covered with diamond seeds can be uniformly distributed, non-uniformly, or localized in a selected area with 105-1013 grains per square centimeter. In some embodiments, seeds of different sizes and characteristics can be used.

[0043] In some embodiments, the diamond layer formed on the diamond seeded substrate may have an sp2 concentration of less than 20% by volume of the diamond layer. In other embodiments, the diamond layer may have an sp2 concentration of less than 20% by volume of the diamond layer. <111> or <100> In yet other embodiments, the highly oriented diamond film may include different crystal orientations in selected regions or layers, wherein <111> and <100> The crystallographic directions are dominant.

[0044] The properties of diamond 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 identified against the background of graphite or other carbon crystal types. Small changes in the band wavenumber can indicate the composition and properties of the diamond. In some embodiments, for a diamond layer or film formed as indicated in the present disclosure, the 1332 cm -1 The full width at half maximum (FWHM) obtained from Raman characterization can be obtained at 5 cm for SiN or other suitable buffer-coated glasses. -1 and 20 cm -1 between, and for RIE (reactive ion etching) or other surface treated glass can be 20cm -1 and 85 cm -1 In other embodiments, the deposited diamond layer can be measured by Raman analysis at 1332 cm -1 The relative amplitude at 1400 cm -1 -1600 cm -1 The relative amplitude is greater than or equal to 0.5:1 compared to the amplitude at 0.1:1. In other embodiments, the diamond layer may have physical properties such as a Vickers hardness of at least 12 gigapascals as measured by nanoindentation. In other embodiments, the Vickers hardness may be greater than 20 gigapascals. In other embodiments, the diamond layer may be measured to exert a compressive stress of less than 50 gigapascals.

[0045] In some embodiments, a polycrystalline diamond or diamond-like carbon (DLC) coating or material may be formed on all or at least a portion of a substrate. In some embodiments, polycrystalline diamond grains sized to be less than 1 micron (1000 nanometers) and greater than 500 nanometers may be used. In other embodiments, the polycrystalline diamond or diamond-like material may include ultra-nanocrystalline (UNCD) 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 may include a range of grain sizes, including larger and smaller grains. In some embodiments, the diamond layer may be formed to have grains less than 1 micron. In some embodiments, the grain size may differ by 50%, 100%, 200%, or 500% greater than or less than the average diamond grain size. In other embodiments, the diamond grain size may remain within 50%, 20%, or 10% of the average grain size. In some embodiments, the diamond layer can be formed by at least 90% nanocrystalline diamond and have the diamond grains that are sized between 2 nanometers and 500 nanometers. In some embodiments, the diamond layer can be formed by at least 90% microcrystalline diamond and have the diamond grains that are sized between 500 nanometers and 1000 nanometers. In other embodiments, the diamond grains can be sized between 500 nanometers and 1000 nanometers. In other embodiments, 90% diamond grains can be sized between 200 nanometers and 300 nanometers.

[0046] In some embodiments, the diamond layer thickness can be selected to be between 20 nanometers and 1000 nanometers. Typically, the diamond grain size will be 50% or less of the diamond layer thickness. In some embodiments that can be used for optical coatings, the diamond layer thickness will be between 20 nanometers and 500 nanometers. For example, in one embodiment, glass or other transparent materials can be coated with a diamond film having a thickness between 100 nanometers and 300 nanometers.

[0047] The diamond layer may have a substantially uniform thickness over all or a limited portion of a surface or substrate. In other embodiments, the thickness may be non-uniform and vary over portions of a surface or substrate. In some embodiments, the diamond layer may be conformal when extending over a cavity, depression, or protrusion in the substrate or surface. In some embodiments, the diamond layer may steadily thin or thicken away from one or more locations on the substrate.

[0048] Multiple diamond layers, differentiated by composition, crystal structure, dopant, grain size, or grain size distribution, can be part of a multilayer coating or film system applied to a substrate. Different diamond layers can be layered on top of a diamond layer or non-diamond material. In certain embodiments, the physical parameters of the diamond layer can be varied continuously or semi-continuously across the layer, either vertically or laterally.

[0049] In certain embodiments, the diamond layer has a thickness, for example, between 30 nm and 150 nm (e.g., 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, or 150 nm, including all ranges and values ​​therebetween). Additionally, the diamond layer can have a root mean square (RMS) surface roughness of less than 2 nm.

[0050] Diamond or DLC can be deposited by chemical vapor deposition (CVD) such as hot wire CVD, microwave CVD, rf-CVD, laser CVD (LCVD) or laser ablation, metal-organic CVD (MOCVD), sputtering, thermal evaporation PVD, ionized metal PVD (IMPVD), electron beam PVD (EBPVD), reactive PVD, cathodic arc and similar deposition. CVD involves the use of a dilute mixture of a carbon-containing gas (such as carbon dioxide or a hydrocarbon, typically methane) and hydrogen, wherein the carbon-containing component content typically varies from about 0.1% to 4% of the total volume flow rate. In one of these techniques, the gas mixture is energized using a metal wire (typically tungsten) that is electrically heated to a temperature in the range of about 170°C to 2400°C. The gas mixture dissociates on the surface of the wire and the carbon, hybridized in the form of diamond, is deposited on a substrate placed below the wire. In operation, the power density at the substrate can be around 300 W / m 2 / min-600 W / m 2 Deposition typically occurs at subatmospheric pressures in the range of 30 mTorr to 300 Torr.

[0051] In some embodiments, thin diamond films can be deposited on substrates at substrate temperatures below 600 degrees Celsius. In other embodiments, deposition can be performed at temperatures between 300 degrees Celsius and 600 degrees Celsius. Advantageously, compared to the typical 700-800 degrees Celsius temperatures used for conventional CVD-mediated diamond film growth, such low temperatures significantly reduce thermal effects (including thermal degradation), stress due to different CTEs, or warping of the substrate. Advantageously, this can allow the use of a wider variety of substrates or coatings.

[0052] In some embodiments, various processes can be used to improve the quality of diamond or other films. These processes can be performed, for example, before seeding, before layer deposition, after layer deposition, or after a metering step to contaminate the surface. For example, the substrate can be subjected to dry processing and / or wet processing, including but not limited to strong or weak acid and / or strong or weak base cleaning, solvent cleaning, ultrasonic agitation, plasma cleaning, ultraviolet (UV), ozone treatment, the application of tetramethylammonium hydroxide, or any other suitable process combination. Plasma cleaning can include subjecting the substrate to a plasma derived from argon and / or oxygen at various concentrations. Post-diamond deposition cleaning processes can be included, such as solvent cleaning, which includes solvents such as acetone and IPA, and plasma cleaning with O2 / Ar gas using RIE or the like to clean the substrate to remove any unwanted residues deposited during the diamond deposition process.

[0053] In some embodiments, glass or other substrates can support multiple thin diamond layers, various intermediate layers, layers pretreated using reactive ion etching (RIE) or other techniques, and top layers. These can be thin single or multilayer metals, ceramics, glasses, or other compositions. The thickness of such layers can be less than 1000 nanometers. Such layers can serve as capping layers, intermediate layers, or buffer layers, and can improve the optical, electrical, thermal, or mechanical properties of the multilayer structure. In some embodiments, the capping layer, intermediate layer, or buffer layer can be transparent and include one or more of the following: metal (e.g., tungsten or titanium); ceramics, dielectric materials, or glasses (e.g., aluminosilicates or borosilicates). In some embodiments, the capping layer, intermediate layer, or buffer layer may include one or more of the following: indium tin oxide, aluminum oxide, aluminum oxynitride, titanium oxide (including but not limited to titanium dioxide), magnesium oxide, silicon dioxide, and hafnium oxide. In other embodiments, the capping layer, intermediate layer, or buffer layer may include one or more of aluminum, silicon, titanium, or boron nitride. The cap layer, intermediate layer or buffer 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 made 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. The thickness of the cap layer, intermediate layer or buffer layer may be in the range of 2 nm to 1000 nm.

[0054] In some embodiments, the deposited diamond film can be cleaned and exposed to a two-dimensional top layer material such as reduced fluorinated graphene oxide, graphene, graphene oxide, or f-silane. In some embodiments, this provides superhydrophobicity or oleophobicity without significantly reducing the properties of the diamond film, including optical transmittance and / or hardness. In one embodiment, graphene oxide can be derived from a chemical suspension of multilayer graphene oxide and spin-coated onto the diamond film and wet-chemically or dry-chemically (plasma) reduced by incorporating fluorine atoms into the material to replace oxygen.

[0055] In some embodiments, the substrate and / or diamond layer may undergo a surface functionalization treatment step. This may include surface functionalization by wet chemistry using spray coating, bias spray coating, ultrasonic spray coating, ultrasonic agitation of a solvent and ketone mixture including, but not limited to, methanol, acetone, isopropanol, ethanol, butanol, or amyl alcohol. The functionalized surface may include hydrocarbon chains, hydroxyl bonds, oxygen end groups, or other suitable chemically active materials.

[0056] In some embodiments, the substrate and / or diamond layer may undergo a surface functionalization treatment step. This may include surface functionalization by wet chemistry using spray coating, bias spray coating, ultrasonic spray coating, ultrasonic agitation of a solvent and ketone mixture including, but not limited to, methanol, acetone, isopropanol, ethanol, butanol, or amyl alcohol. The functionalized surface may include hydrocarbon chains, hydroxyl bonds, oxygen end groups, or other suitable chemically active materials.

[0057] In some embodiments, a single or multiple diamond layers or films may include additional multilayer structures that enable or enhance various uses or features, including those that provide light redirection, interference, cover glass, protective cover, display, window, chemical protection, thermal protection, or mechanical protection. Applications or components that support multilayer diamond layers, films, or coatings may include, but are not limited to, visible or infrared optical devices, windows, optical waveguides, semiconductors, semiconductor coatings, and strong or durable coatings for electronic devices, manufacturing, or tools. Other applications of diamond multilayer coatings may include use in biological substrates or medical devices, or in batteries, fuel cells, electrochemical systems, chemical sensors, general sensing, or integration with other advanced materials.

[0058] As will be appreciated, the described diamond layers, substrates, and non-diamond material films may include various embodiments, characteristics, and combinations, including but not limited to the following additional examples: Example 1 - In a first embodiment, a multilayer transparent diamond structure comprising a nanocrystalline diamond layer and an ultra-nanocrystalline diamond layer can be continuously and conformally coated on a transparent glass substrate to serve as an optically transparent protective coating suitable for use in smartphones, tablets, or laptop computers. For example, a substantially uniform 70-110 nanometer thick nanocrystalline diamond film having a grain size ranging from 20 nanometers to 70 nanometers can be deposited on a conductive indium tin oxide (ITO) film deposited on a transparent glass substrate. In some embodiments, an ultra-nanocrystalline diamond layer having a thickness between 20 nanometers and 500 nanometers and a grain size between 2 nanometers and 10 nanometers can be deposited on the nanocrystalline diamond layer. In some embodiments, the ultra-nanocrystalline diamond layer can have a thickness between 20 nanometers and 200 nanometers, wherein the diamond grain size is between 2 nanometers and 10 nanometers. In some embodiments, the ultra-nanocrystalline diamond layer can have a thickness of less than 50 nanometers, wherein at least 50% of the ultra-nanocrystalline diamond grains are sized between 2 nanometers and 10 nanometers. Alternatively, the glass surface can be functionalized to include a hydrophobic coating or a doping or functionalization layer to support the other diamond coating of hydrophobic or oleophobic coating. The glass substrate can be chemically cleaned with acetone and then cleaned with UV ozone. Alternatively, float glass or similar substrates can be cleaned with acid to remove tin or other metal coatings. In some embodiments, the glass surface can be functionalized to include a hydrocarbon chain derived from solvent decomposition when drying.

[0059] Conventional HF CVD reactors with tungsten, tantalum, or rhenium filaments can be used. The filament diameter, spacing, and number can be adjusted to provide optimal results. In one embodiment, the filament diameter is 0.12 mm to 0.5 mm, the spacing can be 8 mm 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 between 100 liters and 200 liters, with a diameter between 30 cm and 150 cm.

[0060] The reactor may include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature between 500° C. and 600° C. In these temperature ranges, the diamond layer deposition rate may be between 10 nanometers and 100 nanometers per hour.

[0061] Precursor gases including methane, hydrogen, oxygen, and argon can be introduced into the chamber at a pressure of 10 torr to 15 torr. In particular, adding less than 1% oxygen can reduce the temperature required to maintain the desired deposition rate, and oxygen will preferentially etch sp2 deposition areas. 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.

[0062] To ensure consistent grain size, the substrate may 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, a grain size of 5 nm to 50 nm may be used.

[0063] In some embodiments, the diamond film is continuous and conformal on the substrate.

[0064] In addition, the diamond film can have a FWHM of 5-7 and an sp2 concentration of less than 20% by volume. <111> At least 80% of the grains are oriented in the crystallographic direction, the Raman spectral characteristic of diamond (approximately 1332 nm) is between 0.7:1 and 1.2:1 compared to the peak graphite band (1400 nm-1600 nm) as analyzed by Raman, the Vickers hardness is between 20 GPa and 60 GPa, and the transmittance of light through the glass substrate and diamond film at a wavelength of 550 nm exceeds 0.70, with a haze of less than 5%.

[0065] Example 2 - In a second embodiment, a substrate may be coated with: a substantially uniform 100-2000 nanometer thick nanocrystalline diamond layer or film having a grain size in the range of 100 to 2000 nanometers; and a thinner ultra-nanocrystalline diamond layer. In some embodiments, an optional ultra-nanocrystalline diamond layer may be deposited that has a thickness between 20 and 200 nanometers and a grain size between 2 and 10 nanometers. In some embodiments, the ultra-nanocrystalline diamond layer may have a thickness less than 50 nanometers, wherein at least 50% of the ultra-nanocrystalline diamond grains are sized between 2 and 10 nanometers. In one embodiment, the 100-2000 nanometer thick nanocrystalline diamond film and the optional covering ultra-nanocrystalline diamond layer may be further etched, and additional layers or films may be selectively applied to fill the etched diamond and support the formation of a waveguide for data transmission. In some embodiments, the deposited grain size may include diamond grains in the range of 5 to 50 nanometers. The reactor may include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature between 500° C. and 800° C. Within these temperature ranges, the diamond layer deposition rate may be between 10 nanometers and 200 nanometers per hour, or less than 10 nm per hour in other embodiments.

[0066] 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, grain sizes ranging from 5 nm to 15,000 nm can be used, with larger grains typically being reduced in size by sonication or other processing steps. In some embodiments, various grain sizes or ranges of grain sizes can be used, including co-deposited small and large grain sizes. In some embodiments, the seeds are deposited in a manner that ensures that the film is continuous and conformal on the substrate.

[0067] In some embodiments, the diamond layer or film may have a Young's modulus exceeding 80 GPa.

[0068] Embodiment 3 - In the third embodiment, substrate can be coated with multiple layers, comprise diamond layer, ceramic layer or metal layer.In some embodiments, can deposit the substantially uniform 5 nanometers-50 nanometers thick nanocrystalline diamond layer or the film with the grain size of scope between 5 nanometers to 50 nanometers.In some embodiments, can deposit the optional ultra-nanocrystalline diamond layer that can have the thickness between 20 nanometers and 200 nanometers and the grain size between 2 nanometers and 10 nanometers.In some embodiments, optional ultra-nanocrystalline diamond layer can have the thickness less than 50 nanometers, and wherein at least 50% ultra-nanocrystalline diamond grain is set to size between 2 nanometers and 10 nanometers.

[0069] The reactor may include stages capable of supporting heating or cooling of the substrate. In some embodiments, the reactor stages may be configured to provide a substrate deposition temperature between 500° C. and 600° C. In these temperature ranges, the diamond layer deposition rate may be between 10 nanometers and 100 nanometers per hour.

[0070] In the foregoing description, reference is made to the accompanying drawings which form a part thereof, and in which are shown by way of illustration specific exemplary embodiments in which the present disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the concepts disclosed herein, and it should be understood that the various disclosed embodiments may be modified and other embodiments may be utilized without departing from the scope of the present disclosure. Therefore, the foregoing detailed description should not be considered restrictive.

[0071] References throughout this specification to "one embodiment," "an embodiment," "one example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment of the present disclosure. Thus, the phrases "in one embodiment," "in an embodiment," "one example," or "an example" appearing throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, databases, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. In addition, it will be understood that the drawings provided herewith are for explanation purposes to one of ordinary skill in the art and that the drawings are not necessarily drawn to scale.

[0072] Many modifications and other embodiments of the present invention will occur to those skilled in the art having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it should be understood that the present invention is not limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims. It should also be understood that other embodiments of the present invention may be practiced in the absence of elements / steps not specifically disclosed herein.

Claims

1. A diamond-coated glass structure comprising: a glass substrate having a first side and a second side, wherein the second side is chemically modified by ionic substitution; and A CVD-deposited diamond layer is on the first side.

2. The structure of claim 1 wherein the CVD deposited diamond layer comprises less than 20% sp2 carbon.

3. The structure of claim 1 wherein the CVD-deposited diamond layer comprises a plurality of diamond layers.

4. The structure of claim 1 wherein the CVD-deposited diamond layer comprises an ultra-nanocrystalline diamond layer on a nanocrystalline diamond layer.

5. The structure of claim 1 wherein the substrate has a dimension of at least one centimeter.

6. The structure of claim 1, wherein the ion substitution further comprises replacing at least some of the sodium ions with potassium ions.

7. The structure of claim 1, wherein ion replacement further comprises displacing at least some ions on the second side to a penetration depth of less than 100 microns.

8. A diamond-coated glass structure comprising: a glass substrate having a first side and a second side, wherein the first side and the second side are chemically modified by ion substitution and the penetration depth between the first side and the second side is different; and A CVD-deposited diamond layer is on at least one of the first side and the second side.

9. The structure of claim 8 wherein the CVD deposited diamond layer comprises a plurality of diamond layers.

10. The structure of claim 8, wherein the CVD-deposited diamond layer comprises an ultra-nanocrystalline diamond layer on a nanocrystalline diamond layer.

11. The structure of claim 8, wherein the ion substitution further comprises replacing at least some of the sodium ions with potassium ions.

12. The structure of claim 8, wherein ion replacement further comprises displacing at least some ions on the second side to a penetration depth of less than 100 microns.

13. A diamond-coated glass structure comprising: a glass substrate having opposing first and second sides and four edges, wherein the first and second sides and four edges are chemically modified by ion substitution, and wherein the first side has a different penetration depth than the second side and at least one of the four edges; and A CVD-deposited diamond layer is on the first side.

14. The structure of claim 13 wherein the CVD deposited diamond layer comprises a plurality of diamond layers.

15. The structure of claim 13 wherein the CVD-deposited diamond layer comprises an ultra-nanocrystalline diamond layer on a nanocrystalline diamond layer.

16. The structure of claim 13, wherein the substrate has a dimension of at least one centimeter.

17. The structure of claim 13, wherein the ion substitution further comprises replacing at least some of the sodium ions with potassium ions.

18. The structure of claim 13, wherein ion replacement further comprises displacing at least some ions on the second side to a penetration depth of less than 100 microns.

19. A method of forming a diamond-coated glass structure, comprising: providing a glass substrate having a first side and a second side; CVD depositing a diamond layer on the first side; and After CVD diamond deposition, the second side is chemically modified by ion substitution.

20. The method of forming a diamond-encapsulated glass structure of claim 19, wherein the first side of the glass substrate is chemically modified.

21. A method of forming a diamond-coated glass structure, comprising: providing a glass substrate having a first side and a second side; performing a first chemical modification on the first side and the second side by ionic substitution; CVD depositing a diamond layer on the first side; and After CVD diamond deposition, both the first side and the second side are chemically modified a second time by ion substitution.

22. A method of forming a diamond-coated glass structure, comprising: providing a glass substrate having a first side and a second side; performing a first chemical modification on the first side and the second side by ionic substitution; CVD depositing a diamond layer on the first side; and After CVD diamond deposition, only the second side is chemically modified a second time by ion substitution.

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