Diamond devices or structures, and methods for manufacturing diamond devices or structures

Abstract

The present invention provides a diamond device or structure, and a method for manufacturing the same. [Solution] A diamond device or structure (1) is provided, comprising: a plurality of support layers or materials including at least one or more support structures; a plurality of recesses formed by the at least one or more support structures; at least one diamond microseed (MS) and a plurality of diamond nanoseeds (NS) disposed in each of the recesses or plurality of recesses; and at least one diamond layer or film attached to the plurality of support layers or materials (3) and extending between the recesses, wherein diamond columns extending from at least one diamond layer or film to be fixed to at least one diamond layer or film are embedded inside each of the recesses or plurality of recesses, and the plurality of recesses and diamond columns extend through the plurality of support layers or materials (3).

Description

[Technical Field]

[0001] (Field of invention) The present invention relates to diamond devices and structures, and to methods for manufacturing diamond devices and structures. In particular, the present invention relates to diamond devices and structures including diamond seeding and seed dipping methods for growing high-quality diamonds. Such diamond devices or structures can be used, for example, in electronic devices and integrated circuits (ICs), diamond heat spreaders, proximity bonding heat spreaders, and in jewelry, mechanical components, optical and photonic devices, optical and photosensors and optical and photodetectors, biomedical devices, and cutting tools / machining tools. Prior Art Description

[0002] (background) The integration of diamond and GaN is being driven by thermal management purposes and by combining their excellent complementary properties with novel semiconductor heterostructures for power electronics applications. However, growing diamond on GaN is difficult due to the mismatch between high lattice and thermal expansion. Poor adhesion of diamond to GaN and high residual stress after deposition often lead to delamination or cracking of the diamond film, hindering subsequent device fabrication.

[0003] Due to its excellent properties such as high thermal conductivity, wide bandgap, large breakdown field, and high hole mobility, diamond is considered a potentially excellent material for power electronics applications. 1 On the other hand, GaN is also a broad-bandgap semiconductor that possesses a large critical field, high electron mobility, and saturation velocity, and has the capability to produce cost-effective GaN-on-Si wafers on a large scale. 2 .

[0004] High thermal conductivity of diamond film 3、4is used as a heat spreader for thermal management of GaN power electronic devices, and has been shown to significantly reduce thermal resistance, and eliminate hot spots and temperature gradients from both GaN high electron mobility transistors (HEMTs) 5-10 and vertical GaN devices 11 .

[0005] Furthermore, although high-performance n-type GaN devices such as HEMTs with low resistance and high voltage capability are currently used in many power electronics applications 12 , the performance of p-type GaN is still limited mainly due to low hole mobility and poor activation of Mg dopants in GaN 13 . On the other hand, diamond has excellent properties for p-type power electronic devices with high hole concentration and mobility, but still lacks shallow-level n-type dopants 14 . The integration of diamond and GaN can open up new possibilities for novel devices and integrated circuits (ICs) that combine the complementary properties of diamond as a p-type semiconductor and GaN as an n-type semiconductor.

[0006] Different methods have been proposed for diamond-GaN integration, and the most common approach is the integration of GaN on a diamond substrate 15-17 . However, due to the small available size and high cost of diamond substrates, GaN-on-diamond substrates can only be used for high-end applications 2 .

[0007] A lower-cost approach has been proposed by integrating diamond on cost-effective GaN-on-Si substrates, and it has been shown that on this substrate, diamond transistors have excellent device characteristics on AlGaN / GaN-on-Si substrates without polishing the rough diamond surface 18However, the high roughness of as-grown diamonds limits wafer processing using planar process methods. Therefore, polishing is an essential step to obtain a smooth diamond surface and a reliable manufacturing process. However, due to the mismatch in the coefficient of thermal expansion (CTE) between diamond and GaN (a 28% mismatch) 19 CVD diamond films can generate high residual stress during growth (>1.5 GPa). 20 Due to the relatively weak adhesion of diamond to GaN, such high residual stress can cause delamination or cracking of the film, and the diamond film cannot withstand the high mechanical stress of the polishing step.

[0008] Weak diamond adhesion to GaN, primarily via weak van der Waals interactions. 21 Furthermore, the presence of high stress in the film is a significant problem that makes diamond films prone to peeling. 20、22 Currently, low-stress, high-adhesion growth of diamond on GaN and its polishing remain major challenges.

[0009] Several studies have suggested using AlN, SiN, or SiC intermediate layers to improve adhesion by forming strong covalent carbide bonds. 23-26 This also protects GaN from decomposition in CVD reactors at temperatures exceeding 600°C under a hydrogen plasma. 22 However, the presence of an extra thin film between GaN and diamond can introduce high interfacial thermal resistance (TBR) and limit heat conduction. 27 .

[0010] The diamond seeding step before growth can also affect the quality, particle size, thermal conductivity, and TBR of the diamond film. 28、29 10 11 cm -2High-density seeding of substrates using ultra-high-density diamond nanoseeds enables rapid growth and diamond film bonding, which improves adhesion by minimizing GaN decomposition in a hydrogen plasma environment. 30 Recent studies have experimented with mixed-size diamond seeding, growing CVD diamond films on GaN and AlN using micro-seeds and nano-seeds. 31 However, diamond growth on GaN was unsuccessful due to poor adhesion. [Overview of the project]

[0011] The present invention addresses the above limitations by providing a diamond device or structure as described in claim 1, and a method for manufacturing a diamond device or structure as described in claim 48.

[0012] Other advantageous features can be found in the dependent claims.

[0013] The diamond device or structure of this disclosure, and the method for manufacturing the diamond device or structure, solve the above-mentioned problems relating to the adhesion of diamond to a substrate and / or base layer.

[0014] In particular, improved adhesion to GaN, for example, is guaranteed.

[0015] While diamond adhesion to GaN is of particular importance, the diamond devices or structures and methods for manufacturing them as demonstrated herein as proof of concept are not limited to guaranteeing improved adhesion to GaN alone, but are equally applicable to the adhesion of diamond to one or more other materials.

[0016] This document describes a method for fabricating diamond devices or structures, specifically a seed dipping method for efficient seeding and growth of diamond on dissimilar substrates, such as GaN-on-Si. This method enables the growth of high-quality diamond films with large particles, low residual stress, and excellent adhesion to the substrate. The method relies on the microstructure of the substrate and seeding using both micro-seeds and nano-seeds. The seed dipping method provides diamond devices and structures that address the problem of diamond film delamination after growth, and allows for the reliable polishing of the diamond film grown on a GaN substrate, for example, to obtain a smooth diamond-on-GaN substrate.

[0017] Seed dipping methods for seeding and growing or depositing high-quality diamond films are advantageous if they can be performed, for example, on a cost-effective GaN-on-Si substrate. An exemplary high-quality diamond film grown on GaN-on-Si has, for example, 95% sp. 3 / sp 2 Compared to conventional methods, it showed significantly larger particles and lower residual stress (0.2 GPa).

[0018] This method is not limited to the growth of high-quality diamonds, but can be used for the growth of diamonds of other qualities and other stresses, with or without (point and / or expansion) defects, impurities, and material dopants, as well as single-crystal films, polycrystalline films, microcrystalline films, nanocrystalline films, and ultra-nanocrystalline films.

[0019] Furthermore, the excellent adhesion achieved by this method allows for reliable, non-peel-free polishing of diamond films grown on GaN-on-Si, for example, resulting in smooth diamond-on-GaN substrates with a root mean square roughness of, for instance, sub-nanometers. This method opens up many new possibilities for the development of high-performance power electronic devices and other electronic devices, integrated devices, and heterostructure devices with excellent thermal management based on the diamond-on-GaN platform.

[0020] Furthermore, the method is not limited to GaN-on-Si substrates and can be extended to other substrates or materials to combine the remarkable properties of diamond with other types of devices.

[0021] For example, the method can be used to deposit a diamond layer or material onto micro-machine parts such as (micro) machine parts and cutting tools, but not limited to, formed from different materials such as steel, stainless steel, sapphire, borosilicate, quartz, alumina, and tungsten carbide. The method of this disclosure can also be used to deposit a diamond layer or material onto sensors and / or biosensors, detectors and / or biodetectors formed from different types of materials.

[0022] The method of the present disclosure can also ensure the deposition of a diamond layer or material to form and / or fabricate an optical platform of different types of materials. The method of the present disclosure can also ensure the deposition of a diamond layer or material to form and / or fabricate color centers, such as NV center arrays, onto different types of materials.

[0023] The method disclosed herein can also be used for the deposition of diamonds having different semiconductor behaviors, including intrinsic, undoped, unintentionally doped, and (n-type and / or p-type) diamond layers doped at different doping concentrations. Using this method, it is possible to ensure the deposition of diamonds having different thermal conductivity ranges, for example, from 50 W / mK to 3000 W / mK, for thermal control applications.

[0024] The methods disclosed herein can also be used for depositing diamond layers or materials using different CVD deposition methods, including, but are not limited to, plasma (or microwave plasma) CVD, low-temperature plasma CVD, atmospheric plasma CVD, plasma torch, and hot filament CVD.

[0025] The other objectives, features, and advantages of the present invention, as well as methods for realizing them, will become clearer, and the present invention itself will be best understood by considering the following description with reference to the accompanying drawings illustrating some preferred embodiments of the present invention. [Brief explanation of the drawing]

[0026] [Figure 1A] Figure 1A is a schematic diagram showing an exemplary embodiment of a diamond device or structure according to the present disclosure. [Figure 1B] Figure 1B is a schematic diagram showing an exemplary embodiment of a diamond device or structure according to the present disclosure. [Figure 1C] Figure 1C is a schematic diagram showing an exemplary embodiment of a diamond device or structure according to the present disclosure. [Figure 1D] Figure 1D is a schematic diagram showing an exemplary embodiment of a diamond device or structure according to the present disclosure. [Figure 1E] Figure 1E is a schematic diagram showing an exemplary embodiment of a diamond device or structure according to the present disclosure. [Figure 2] Figure 2A is a schematic diagram of the fabrication of an exemplary diamond device or structure using the method according to the present disclosure. The method may include some or all of the exemplary steps, namely, I. providing at least one support layer or material, e.g., a GaN-on-Si substrate; II. etching holes into the substrate; III. seed dipping using both diamond nanoseeds and microseeds; IV. a (CVD) diamond growth step; and V. diamond polishing step. Figure 2B is an optical microscope image of an exemplary GaN-on-Si substrate seeded and constructed by the seed dipping method of the present disclosure. Figure 2C is a magnified image showing microseeds effectively arranged within the dipped substrate. Figure 2D is an SEM image of a high-density coating of nanoseeds across the entire surface of the substrate. [Figure 3]Figures 3A to 3D are cross-sectional SEM images of samples with high aspect ratio seed dipping, with aperture widths of (A) 4 μm, (B) 10 μm, (C) 20 μm, and (D) 50 μm. Figure 3E is an SEM image of a sample with a 4 μm pore / aperture, showing microseed containment throughout the entire depth of the pore, with only the portion (approximately) 5 μm long from the aperture or the top of the pore contributing to diamond growth. Figure 3F is a magnified image of the dashed area in Figure 3E, showing that both microseeds and nanoseeds contribute to diamond growth. [Figure 4] Figure 4A is a cross-sectional SEM image of a diamond film grown on an exemplary AlGaN / GaN-on-Si substrate using the optimized seed dipping method of this disclosure. The inset shows a diamond-filled, dipped region where the initial microseeds are identifiable. Figure 4B is a high-resolution XRT image of the substrate from Figure 4A, where the material is displayed in grayscale based on X-ray transmission, with some areas obscured to form a cross-sectional image, demonstrating seamless and effective seed dipping and diamond growth. [Figure 5] Figure 5A shows the stress profile along the diamond film thickness resulting from seed dipping using different seeds. Figure 5B shows the phase purity (sp3 / sp2 ratio) of the carbon bonds. Figure 5C shows the full width at half maximum (FWHM) of the peak corresponding to diamond in the Raman spectrum. Figure 5D shows the X-ray photoelectron spectroscopy (XPS) data of the diamond surface, with an inset showing the spectrum of oxygen atoms. Figure 5E is an SEM image of a diamond film grown on a chip, with regions seeded by mixed seed dipping and regions with only nanoseeds and no seed dipping. [Figure 6]Figure 6A shows top and cross-sectional SEM images of the diamond as it is grown. Figure 6B shows top and cross-sectional SEM images of the diamond after polishing. Figure 6C is an atomic force microscope image of the polished diamond surface having a root mean square roughness Rq = 0.6 nm. Figure 6D shows an AlGaN / GaN-on-Si chip on which a diamond film is reliably grown and polished using the seed dipping method of this disclosure to obtain a smooth and transparent diamond surface. Figure 6E shows the Raman spectra of the diamond surface before and after polishing, which do not show significant changes. [Modes for carrying out the invention]

[0027] (Detailed description of several embodiments) In this specification, whenever possible, the same reference numerals shall be used to indicate identical elements common to the drawings.

[0028] Figures 1C, 1D, 2A-2D, 3A, 3E, 3F, 4A, 4B, and 5A-5D illustrate exemplary diamond devices or diamond structures 1 according to the present disclosure. Figures 1A-1D and 2A illustrate exemplary methods for manufacturing diamond devices or diamond structures 1.

[0029] The diamond device or structure 1 comprises, for example, at least one support layer or material 3, and includes at least one or more support structures 5 within the at least one support layer or material 3. The diamond device or structure 1 further includes a plurality of holes, small indentations, dents, recesses, grooves, or recesses 7 defined by the at least one or more support structures 5.

[0030] The diamond device or structure 1 may further include at least one or more diamond microseeds MS and a plurality of diamond nanoseeds NS arranged in each of the recesses 7 or a plurality of recesses 7.

[0031] The device or structure 1 may include, for example, a single support layer or material 3 provided on / deposited or superimposed on a substrate or holding substrate 3A, or be composed of such a layer. A single support layer or material 3 provided on or superimposed on the substrate or retaining substrate 3A may be, for example, integral with or composed of the same material as the substrate or retaining substrate 3A. Figure 1C shows an exemplary integral structure in which the support layer or material 3 and the substrate substrate 3A are composed of the same material. The support layer or material 3 is defined, for example, by recesses 7 defined in the integral material and one or more support structures 5. The remaining material without recesses and support structures defines the substrate or retaining substrate 3A. One or more additional layers or materials may be provided, for example, on the support layer or material 3 in Figure 1C.

[0032] The device or structure 1 may include, for example, a plurality of layers or materials 3 provided on / deposited or superimposed on a substrate or holding substrate 3A, or composed of such layers.

[0033] The multiple support layers or materials 3 are, for example, stacked layers or materials 3.

[0034] The device or structure 1 may include, for example, a single layer or material 3 or multiple layers or materials 3 provided on / deposited or superimposed on multiple substrates or retaining layers / materials 3A, or provided on / deposited or superimposed on a single substrate or retaining layer / material 3A.

[0035] The outer layer or material 3 (or its outer surface) on which the diamond layer or material 9 is deposited or directly deposited is, for example, a layer or material without diamond.

[0036] Figures 1A, 1B, 1E, and 2 show further exemplary devices or structures 1 including or comprising a substrate or retaining substrate or layer 3A.

[0037] The support layer or material 3 may include, for example, GaN (gallium nitride) or AlGaN (aluminum gallium nitride), AlN (aluminum nitride), a buffer layer, or a superlattice, or be composed of such.

[0038] The support layer or material 3 may not contain AlN, for example, or the outer support layer or material 3 on which a diamond layer or material 9 is provided or deposited may not contain AlN.

[0039] The support layer or material 3 may, for example, contain or be composed of AlGaN in which the GaN and Al content changes, or contain or be composed of AlGaN in which the GaN and Al content changes, and may also contain other atoms or materials, such as carbon or iron, or may contain semiconductor dopants, such as Si and / or Mg.

[0040] As described above, the GaN and / or AlGaN layer can be placed, for example, on a substrate 3A. The substrate 3A may contain or be composed of, for example, Si (silicon), SiC (silicon carbide), Ga2O3 (gallium oxide), GaAs (gallium arsenide), sapphire, diamond, borosilicate, or quartz.

[0041] The substrate 3A and / or the support layer or material 3 may include or be composed of, for example, steel, stainless steel, sapphire, borosilicate, quartz, alumina, or tungsten carbide.

[0042] Figures 2B to 2D, and Figures 3A, 3E, 3F, and 4 show exemplary diamond devices 1 according to the present disclosure, where the support layer or material 3 contains GaN, and the substrate 3A on which the GaN is provided contains or is made of Si.

[0043] One or more support structures 5 are arranged within a support layer or material 3, or within multiple support layers or material 3. One or more support structures 5 can be formed from, for example, a part or part of one or more support layers or material 3 by selective removal or etching such as machining, chemical etching, physical and / or chemical plasma etching, or laser microstructuring, thereby defining the recess 7.

[0044] Alternatively, one or more support structures 5 can be formed, for example, by selective growth or deposition of one or more support layers or materials on a substrate 3A, thereby defining the recess 7.

[0045] The recess 7 (of the removal portion) can partially cross one or more support layers or one or more materials 3, with the bottom of the recess 7 or the floor FL being defined by the support layer or material 3.

[0046] The recess 7 can completely traverse one or more support layers or one or more materials 3, with the bottom or floor FL of the recess 7 defined by the substrate or retaining substrate or layer 3A. In another exemplary embodiment, the recess 7 can partially extend into the substrate or retaining substrate or layer 3A, with the bottom or floor FL of the recess 7 defined by the substrate or retaining substrate or layer 3A. This can, for example, allow for further adhesion or fixation of the diamond layer 9 to the substrate or retaining substrate or layer 3A.

[0047] One or more support structures 5 include or consist of, for example, columns, supports, or projections. One or more support structures 5 extend upward UD and / or away from the substrate or retaining substrate or layer 3A. One or more support structures 5 extend upward UD and / or away from the plane UDP defined by the substrate or retaining substrate or layer 3A and / or the diamond layer or material 9.

[0048] One or more support structures 5 extend in a direction UD perpendicular to the plane UDP defined, for example, by the substrate or holding substrate or layer 3A and / or the diamond layer or material 9.

[0049] One or more support structures 5 may include, for example, a plurality of intersecting and projecting first elongated ridges 5a and second elongated ridges 5b that define or define a grid shape (see, for example, dashed elements 5a, 5b in Figure 2D). However, such contours are shown only as examples, and the contours of the support structure 5 are not limited to such contours.

[0050] As described above, one or more support structures 5 define or form a plurality of recesses 7. As described above, the recesses 7 extend partially or completely through the support layer or material 3 or a plurality of support layers or materials 3.

[0051] One or more support layers or one or more materials 3 include, for example, a plurality of regularly repeating recesses 7 and / or a plurality of periodic recesses 7.

[0052] The multiple recesses 7 may define or include, for example, a symmetrical pattern of repeating recesses 7. The recesses 7 may repeat periodically, for example. The distance between each recess 7 may have a value P, or the recesses may or may not repeat periodically. When repeating periodically, the repetitions may occur at the same periodic value P.

[0053] The recess 7 is separated, for example, by a distance SP (see, for example, Figure 1D), and the distance SP may have a value of, for example, (i) WD / 2 to (ii) 10 × WD (10 times WD), 20 × WD, or 30 × WD, and in the exemplary embodiment of Figure 2C, it is 2 μm to 40 μm, for example, 8 μm.

[0054] The recesses 7 may be configured or arranged as, for example, a periodically repeating array of recesses, or arranged in a periodic array configuration. A periodic configuration can define a symmetrical geometric shape or pattern. This allows multiple recesses 7 to be configured as a periodic recess array, or arranged in a periodic array configuration across the support layer or material 3, or on a portion of the support layer or material 3.

[0055] The arrangement of recesses may be aperiodic, partially periodic, or have a changing period. The arrangement can define, for example, an asymmetrical geometric shape or pattern. The recesses 7 in these arrangements may also be separated by, for example, a distance SP.

[0056] The recesses or each recess 7 may have a symmetrical cross-sectional or geometric shape (for example, with respect to the UDP direction), such as a roughly rectangular or square shape as shown. However, in addition to or instead of the recess 7, the recess 7 may have other cross-sectional shapes, such as a circular, triangular, trapezoidal, or elliptical contour.

[0057] In addition, or instead, the recesses or each recess 7 may have an asymmetrical cross-sectional shape.

[0058] The recesses or each recess 7 may have a symmetrical top surface shape or geometric shape, for example, a roughly rectangular or square shape as shown. However, in addition to or instead of the recess 7, the recess 7 may have other cross-sectional shapes, such as a circular, triangular, trapezoidal, polygonal, or elliptical contour.

[0059] In addition, or instead, the recesses or each recess 7 may have an asymmetrical upper surface shape.

[0060] One or more recesses 7 may have an opening width WD in the (in-plane) planar UDP of the support layer or material 3, for example, a value of 1 μm to 2000 μm, or 1 μm to 1000 μm, or 1 μm to 500 μm, or 1 μm to 400 μm, or 1 μm to 250 μm, or 1 μm to 100 μm, or 1 μm to 50 μm, or 2 μm to 200 μm, or 2 μm to 50 μm, or 2 μm to 20 μm, or 4 μm to 15 μm, or 3 μm to 6 μm. The opening width WD may have a value of, for example, 4 μm to 10 μm, or a value of, for example, 4 μm or 8 μm.

[0061] The recesses 7 may, for example, have non-identical or different opening widths WD. The recesses 7 may include, for example, a plurality of recesses 7 having a first opening width WD1 and a plurality of recesses 7 having a second opening width WD2, where the first opening width and the second opening width are different values. For example, a plurality of recesses 7 having a third opening width and a fourth opening width may be included. The values ​​of the first opening width WD1 and the second opening width WD2 are, for example, the values ​​described above for the opening width WD.

[0062] One or more recesses 7 may have a depth DP extending in a direction UD perpendicular to the (in-plane) planar direction UDP of the support layer or material 3, or in the extensional direction of the support structure 5, and this depth DP may have a value of, for example, 1 μm or 2 μm to 1000 μm, for example, 500 μm, or 2 μm to 300 μm or 400 μm, or 2 μm to 100 μm, or 2 μm to 10 μm or 20 μm, for example, 5 μm or 9 μm, or 2 μm to 5 μm.

[0063] The recesses 7 may have, for example, non-identical or different depths DP. The recesses 7 may include, for example, a plurality of recesses 7 having a first depth DP1 and a plurality of recesses 7 having a second depth DP2, where the first opening depth and the second opening depth are different values. For example, a plurality of recesses 7 having a third depth and a fourth depth may be included. The values ​​of the first opening depth DP1 and the second opening depth DP2 are, for example, the values ​​described above for the depth DP.

[0064] As described above, the in-plane or planar UDP may be defined, for example, by the plane of the extension of the substrate or retaining substrate or layer 3A, and / or the diamond layer or material 9, and / or the support layer or material 3. As described above, the direction UD is, for example, the direction extending upward UD and / or away from the substrate or retaining substrate or layer 3A. The direction UD is, for example, perpendicular to the plane defined by the substrate or retaining substrate or layer 3A, and / or the diamond layer or material 9, and / or the support layer or material 3.

[0065] The recess 7 is located, for example, in at least one support layer or at least one region or multiple separate or dispersed regions of the material 3, or the recess 7 is located throughout at least one support layer or the entire material 3.

[0066] The recesses 7 are, for example, located at least 1%, 5%, 10%, 20%, or 30% of the surface area of ​​at least one support layer or material 3. The recesses 7 are, for example, located at 1% to 90%, 5% to 70%, 5% to 50%, 10% to 40%, 20% to 40%, or 30% to 40% of the surface area of ​​at least one support layer or material 3.

[0067] As described above, at least one or more diamond microseeds MS and multiple diamond nanoseeds NS are arranged, for example, in each or multiple recesses 7.

[0068] Each recess 7 (or each recess 7) includes at least one wall W that completely encloses or extends to completely enclose one or more diamond microseeds MS. The one or more diamond microseeds MS are all or partially located within the enclosure or space defined by at least one wall W.

[0069] One or more support structures 5 include or define at least one wall W.

[0070] The support structure 5 defines the opening OP and upper enclosure UE of one or more recesses 7. For example, the edge or outer edge RM of one or more support structures 5 defines the opening OP.

[0071] The upper enclosure UE of the recess 7 can extend, for example, along the entire depth DP of the recess 7 up to the floor FL of the recess 7 (see, for example, Figure 1B).

[0072] Alternatively, or in addition, the upper enclosure UE of the recess 7 may, for example, partially extend along the depth DP of the recess 7 and not extend to the floor FL of the recess 7 (see, for example, Figures 2E and 2F).

[0073] One or more support structures 5 may include, for example, an upper section UP and a lower section LP. For example, the upper section UP defines the upper half of the support structure 5, and the lower section LP defines the lower half of the support structure 5 (see, for example, Figure 3E).

[0074] The upper part UP of the support structure 5 defines the opening OP and upper enclosure UE of one or more recesses 7, the upper enclosure UE extending partially within or along the depth DP of the recess 7. The lower part LP of the support structure 5 defines, for example, the lower enclosure LE of one or more recesses 7. The upper enclosure UE is positioned, for example, in the upper quarter of the recess 7 with respect to the opening OP, or in the upper 15% or 10% of the recess 7. The lower enclosure LE is positioned, for example, in the lower half or lower quarter of the recess 7 with respect to the opening OP.

[0075] At least one diamond microseed MS is placed, for example, within an opening OP and / or an upper enclosure UE. The upper enclosure UE includes the opening OP.

[0076] One or more microseeds MS can substantially occupy or fill, for example, the opening OP or width WD of the upper enclosure UE of the recess 7. One or more microseeds MS can substantially occupy or fill, for example, the depth DP of the upper enclosure UE or the depth DP of the recess 7. This allows for sufficient adhesion of the diamond layer 9 of device 1. The size and dimensions of the recess 7 in the exemplary embodiments, which illustrate the innovative concept of this disclosure and are described in more detail below, are presented as examples, and it should be noted that this disclosure is not limited to such dimensions or sizes.

[0077] The diamond microseed MS has a size / extension DD or diameter DD which is, for example, 40% to 95%, 60% to 95%, 75% to 90%, or 75% to 95% of the size or diameter of the opening OP of the recess 7.

[0078] The size / extension or diameter of the diamond microseed MS and / or aperture OP can be measured, for example, in the plane of the support layer or material 3 (or substrate 3A), or in the (in-plane) planar UDP direction (see, for example, Figure 1B).

[0079] The size / extension or diameter is measured between the outer ends of the microseed MS. The size / extension DD or diameter DD can be defined, for example, as the maximum or longest size / extension DD or maximum or longest diameter DD measured or determined in the direction extending within the plane defined by one or more supporting materials or layers 3 that hold or surround the diamond microseed MS.

[0080] In other words, the size / extension DD or diameter DD of the diamond microseed MS is between 0.6 times and 0.95 times the size or diameter of the opening OP, or between 0.75 times and 0.95 times the size or diameter of the opening OP.

[0081] As mentioned above, the size or diameter of the aperture OP can be measured, for example, in the (in-plane) planar direction UDP. The size or diameter of the aperture OP can be measured, for example, using scanning electron microscopy / microscope SEM, atomic force microscopy (AFM), or optical microscopy. The size / extension DD or diameter DD of the diamond microseed MS can be measured, for example, using SEM, atomic force microscopy (AFM), or optical microscopy.

[0082] The diamond microseed MS may have or define a cross-sectional area AA that is, for example, 30% to 95%, 60% to 95%, or 75% to 95% of the cross-sectional area defined by the aperture OP of the recess 7. For example, these cross-sectional areas can be measured using, for example, a scanning electron microscope (SEM) or optical microscope, as well as the size or diameter of the aperture OP in the (in-plane) planar UDP.

[0083] The depth DP of the upper enclosure UE and / or recess 7 may be, for example, 60% to 1000%, 60% to 500%, 80% to 150%, or (i) 60%, 80%, or 100% to (ii) 120% of the size / extension or diameter of at least one diamond microseed MS. For example, the size / extension or diameter of the diamond microseed MS is measured in direction UD, which is, for example, the direction of extension of one or more support structures 5, and / or the direction extending away from the substrate or retaining substrate or layer 3A, and / or the diamond layer or material 9, and / or the substrate support layer or material 3. Direction UD is, for example, perpendicular to a plane defined by the substrate or retaining substrate or layer 3A, and / or the diamond layer or material 9, and / or the support layer or material 3. The size / extension or diameter is measured, for example, between the outer ends of the microseed MS. The size / extension DD or diameter DD can be defined, for example, as the maximum or longest size / extension DD or maximum or longest diameter DD measured or determined in this direction.

[0084] One, two, or three diamond microseeds MS are placed or held, for example, within an opening OP and / or an upper enclosure UE. One, two, or three diamond microseeds MS occupy or fill, for example, the cross-sectional area defined by the opening OP of the recess 7. One, two, or three diamond microseeds MS occupy or fill, for example, the depth DP of the upper enclosure UE and / or the recess 7.

[0085] Figure 4A shows, for example, one diamond microseed MS placed or held within the opening OP and / or upper enclosure UE. Multiple nanoseeds may be placed or held simultaneously within the opening OP and / or upper enclosure UE together with the microseed MS.

[0086] One or more diamond microseed MSs may include, or be composed of, microdiamond particles or primary particles and / or non-aggregated or aggregated particles, for example, produced by crushing or cutting natural or synthetic diamond particles, or synthesized in a diamond reactor. Diamond microseed MSs may include, or be composed of, single-crystal or polycrystalline diamond particles, chips, or plates of irregular or regular shapes.

[0087] The size or dimensions of the diamond microseed MS can be determined using a scanning electron microscope (SEM) or confocal microscope, as described above. The particle size distribution can be measured or determined by dynamic light scattering (DLS), acoustic spectroscopy, or differential sedimentation.

[0088] The diamond microseed MS may contain or be composed of particles or crystals having, for example, a diameter or size / extension of 1 μm to 2000 μm, 1 μm to 500 μm, 1 μm to 250 μm, 1 μm to 100 μm, or 1 μm to 50 μm. The particles or crystals may have, for example, a diameter or size / extension of 2 μm to 20 μm or 3 μm to 7 μm, or a diameter or size / extension of 3 μm or 4 μm. The size / extension or diameter of the diamond microseed MS can be measured, for example, using the SEM or confocal microscope described above. The size / extension or diameter is measured, for example, between the outer ends of the microseed MS. The diamond microseed MS may have a diameter or size / extension within or of the above values ​​when measured in either or both of the directions described above with respect to the measurement or determination of the diameter or size / extension, for example, direction UD and / or UDP.

[0089] As described above, multiple diamond nanoseeds NS can be placed in each recess 7 or multiple recesses 7. The upper UP and / or upper enclosure UE may include, for example, multiple dispersed diamond nanoseeds NS.

[0090] For example, one or more diamond nanoseeds NS include or consist of nanodiamond particles or primary particles and / or non-aggregated or aggregated particles, produced, for example, by a standard diamond detonation process using an oxygen-deficient explosive mixture of TNT / RDX exploded in a closed chamber, or synthesized in a diamond reactor.

[0091] Diamond nanoseeds NS may include, for example, diamond crystals, for example, spherical diamond crystals, or be composed of them.

[0092] The size / extension or diameter of diamond nanoseeds (NS) can be determined using particle size distributions measured by SEM, high-resolution transmission electron microscopy (HRTEM), transmission electron microscopy (TEM), atomic probe tomography, SAXS (small-angle X-ray scattering), and ultra-SAXS, as well as dynamic light scattering (DLS).

[0093] Diamond nanoseed NS includes or consists of particles having a diameter or size / extension of, for example, <1000nm, for example, 1nm (or 2, 3, 4, or 5nm) to less than 1000nm, or 1nm (or 2, 3, 4, or 5nm) to 900nm, or 1nm (or 2, 3, 4, or 5nm) to 500nm, or 1nm (or 2, 3, 4, or 5nm) to 300nm, or 1nm (or 2, 3, 4, or 5nm) to 200nm, or 1nm (or 2, 3, 4, or 5nm) to 100nm, or 1nm (or 2, 3, 4, or 5nm) to 50nm, or for example, 1nm or 3nm to 15nm, or for example, 4nm to 11nm. Diamond nanoseed NS includes or consists of particles having a diameter or size / extension of, for example, 5nm. As mentioned above, the size / extension or diameter of a diamond nanoseed NS can be measured, for example, using SEM, TEM, or HRTEM. The size / extension or diameter is measured, for example, between the outer ends of the nanoseed NS. The size / extension or diameter can be defined, for example, as the shortest or longest size / extension or shortest or longest diameter measured or determined in the nanoseed NS.

[0094] The particle size of the diamond microseed MS may be, for example, (i) 10 times, 50 times, 100 times, or 1000 times to (ii) 2000 times the particle size of the diamond nanoseed NS.

[0095] Diamond microseeds MS and / or diamond nanoseeds NS include or consist of single-crystal or polycrystalline diamond, or intrinsic or doped single-crystal or polycrystalline diamond, which may or may not have defects or color centers.

[0096] One or more microseeds (MS) define, for example, nucleation sites or coalescence sites in diamond crystal growth. Nanoseeds (NS) define, for example, nucleation sites in conformal diamond growth.

[0097] As described above, each recess 7 or a plurality of recesses 7 is defined by at least one wall W and at least one floor FL. A plurality of diamond nanoseeds NS are arranged or held, for example, in at least one wall W and / or at least one floor FL.

[0098] At least one wall W completely encloses one or more microseeds MS. At least one wall W also extends to the support structure 5, i.e., in the upward direction UD and / or away from the substrate or retaining substrate or layer 3A. At least one wall W extends, for example, in the direction UD and / or away from the plane UDP defined by the substrate or retaining substrate or layer 3A and / or the diamond layer or material 9.

[0099] One or more microseeds MS are placed entirely or partially within at least one wall W, or within an enclosure or space defined by at least one wall W. Multiple diamond microseeds MS are placed, for example, within each recess 7 or within multiple recesses 7. For example, as seen in Figures 3A, 3E, and 3F, the diamond microseeds MS are stacked, for example, to fill each recess 7 or to fill multiple recesses 7.

[0100] For example, if the upper enclosure UE of the recess 7 extends partially along the depth DP of the recess 7 and does not extend to the floor FL of the recess 7 (see, for example, Figures 2E and 2F), then microseeds MS can be stacked inside the recess 7.

[0101] The microseeds MS are stacked, for example, so as to extend to the upper enclosure UE of the recess 7. The microseeds MS are stacked, for example, so as to extend to a position within at least 60%, 40%, 20%, 15%, 10%, or 5% of the opening OP or the outer edge RM of the opening OP of the recess 7, or to a position within or surrounded by the opening OP or the outer edge RM.

[0102] For example, as shown in Figures 3A and 3E, the diamond microseeds MS are stacked, for example, from the floor FL of the recess 7.

[0103] The support structure 5 and the upper part UP include, for example, a first wall FW, a second wall SW, and an upper landing UL extending between the first wall FW and the second wall SW. Multiple diamond nanoseeds NS can be arranged or dispersed, for example, in the upper landing UL and in the first wall FW and the second wall SW.

[0104] The upper section UP may include, for example, multiple walls W and multiple upper landings UL extending between the walls W, and multiple diamond nanoseeds NS are arranged or dispersed in the upper landings UL and the walls W.

[0105] For example, as shown in Figures 1D and 1E, the diamond nanoseeds NS are dispersed or attached to the support layer or the surface 11 of material 3. The diamond nanoseeds NS are, for example, 1 × 10⁻⁶. 8 cm -2 ~1 × 10 13 cm -2 or 1 × 10 9 cm -2 ~1 × 10 12 cm -2 or 1 × 10 10 cm -2 ~1 × 10 12 cm -2 or 10 8 cm -2 ~10 14 cm -2 or 10 8 cm -2 ~10 13 cm-2 or 10 9 cm -2 ~10 13 cm -2 or 10 9 cm -2 ~10 12 cm -2 It is dispersed or attached to the surface 11 at a density of . The surface 11 includes, for example, a planar surface and a surface defined by the walls and floor of the recess 7.

[0106] The diamond device or structure 1 may further include a diamond layer 9 attached to at least one support layer or material 3. The diamond layer 9 may be attached, for example, directly to the support layer or material 3.

[0107] The diamond layer 9 is, for example, a high-purity diamond layer containing at least 95% carbon atoms. The diamond layer 9 has a thickness of, for example, >6 μm.

[0108] The diamond layer 9 may be, for example, a doped diamond layer 9, for example, a doped p-type. One or more support layers or one or more materials 3 may be, for example, doped n-type. The diamond layer 9 may have different regions with different doping types and different dopant atom concentrations. The diamond layer 9 may have color centers, for example, NV centers.

[0109] The diamond layer 9 may be, for example, a polished diamond layer 9. The polished diamond layer 9 can be directly attached to the support layer or material 3. The polished diamond layer 9 may have, for example, a surface roughness of sub-nanometers.

[0110] The diamond device or structure 1 may, for example, have no intermediate layer between the diamond layer 9 and at least one support layer or material 3. The diamond device or structure 1 may, for example, have no AlN intermediate layer between the diamond layer 9 and at least one support layer or material 3, no SiN intermediate layer, or no SiC intermediate layer.

[0111] The diamond layer 9 extends, for example, from microseeds MS located in the opening OP and / or upper enclosure UE, and extends away from the support layer or material 3. The diamond layer 9 extends, for example, only from the diamond microseeds MS in the opening OP and / or upper enclosure UE, and / or only from a plurality of nanoseeds NS dispersed in the support layer or material 3.

[0112] The diamond microseeds MS are placed in the recesses 7, and the diamond nanoseeds NS are dispersed on the support layer or material 3 and within the recesses 7, chemically bonding and / or mechanically fixing or fixing the diamond layer 9 to the support layer or material 3.

[0113] Both diamond microseeds MS and diamond nanoseeds NS can define nucleation sites or coalescence sites for diamond crystal growth on at least one support layer or material 3.

[0114] For example, as shown in Figures 4A and 4B, the device or structure 1 includes diamond columns embedded in each or a plurality of recesses 7. The columns extend, for example, from the floor FL of the recess 7. This ensures strong adhesion of the diamond layer 9 and high shear strength at the diamond 9 / layer 3 interface.

[0115] For example, diamond growth may not be present in the lower enclosure LE of each recess 7 or a plurality of recesses 7.

[0116] The diamond device or structure 1 may, for example, be included in an electronic device or integrated circuit, or may be further processed to form an electronic device or integrated circuit.

[0117] This disclosure also relates to a method for manufacturing a diamond device or structure 1. Figure 2A is a schematic diagram showing different possible steps of an exemplary diamond device or structure manufacturing method according to this disclosure.

[0118] The method includes, for example, providing at least one support layer or material 3 containing at least one or more support structures 5 within at least one support layer or material 3, and a plurality of recesses 7 defined by the support structures 5. The method further includes performing diamond seeding to provide at least one diamond microseed MS and a plurality of diamond nanoseeds NS in each or a plurality of recesses 7.

[0119] Providing one or more support layers or one or more materials 3 may include, for example, providing at least one support layer or material 3 or multiple overlapping support layers or materials 3, and etching or removing one or more support layers or one or more materials 3 to form a plurality of recesses 7 inside.

[0120] As described above, for example, there may be a single support layer or material 3 provided on / deposited or superimposed on the substrate or holding substrate 3A, or there may be multiple support layers or materials 3 provided on / deposited or superimposed on the substrate or holding substrate 3A. Etching can be performed by partially or completely penetrating a single support layer or material 3, partially or completely penetrating multiple support layers or materials 3, or completely penetrating one or more support layers or one or more materials 3, and partially penetrating the substrate or holding substrate 3A.

[0121] If the device or structure 1 includes a plurality of support layers or materials 3, the etching of the plurality of support layers or materials 3 is therefore carried out to form a plurality of recesses 7 within the plurality of support layers or materials 3. If the device or structure 1 includes a substrate 3A and at least one or more layers attached to the substrate 3A, the etching of at least one or more layers attached to the substrate 3A is carried out to form a plurality of recesses 7 only within the at least one or more layers, or within the at least one or more layers and the substrate 3A.

[0122] As mentioned above, etching is performed to create the recess 7 and the support structure 5.

[0123] For example, etching or removal can be performed using reactive ion etching (RIE), plasma etching, ion milling, chemical etching, mechanical etching, laser etching, or machining. A mask layer is provided on a support layer or material 3, for example, to form etchings at desired locations and result in a desired recess arrangement or pattern.

[0124] After etching one or more materials to a desired depth, the mask layer can be removed.

[0125] The mask layer is, for example, a hard mask layer that allows for sufficient material etching depth. At least one material, such as SiO2, HSQ (hydrogen silsesquioxane), photoresist, or a metal, such as Pt, can be used as the hard mask layer.

[0126] Diamond seeding may include, for example, placing microseeds MS on the outer surface 11 of a support layer or material 3, stirring the support layer or material 3 to transfer the microseeds MS into each or a plurality of recesses 7, and placing nanoseeds NS on the outer surface 11 of a support layer or material 3, stirring the support layer or material 3 to disperse the nanoseeds NS within each or a plurality of recesses 7 and across the surface 11 of the support layer or material 3.

[0127] Stirring may be carried out, for example, by ultrasonic stirring.

[0128] Diamond seeding may include providing microseeds and / or nanoseeds, for example, by immersion in one or more suspensions containing diamond seeds, drop casting, spraying, electrostatic spraying, or spin coating.

[0129] Diamond seeding may include providing microseeds by, for example, placing diamond seeds, such as diamond plates or chips or (large) particles, in each or a plurality of recesses 7, for example, manually or using a pick-and-place machine.

[0130] The particle size of the microseeds MS to be provided on the support layer or the outer surface 11 of material 3 can be selected based on, for example, the D50 median diameter or the particle size of the microseeds MS determined based on one of the measurement means described above. The particle size of the microseeds MS is selected based on the size of the opening OP of the recess 7, for example, to be relatively close to the size of the opening OP of the recess 7, so as described above, the recess 7 is substantially filled. Thus, a filling is obtained in which the size of the opening OP of the recess 7 is adapted to the particle size (or average particle size), or vice versa.

[0131] The particle size of the nanoseeds NS that will be provided on the support layer or the outer surface 11 of material 3 can be selected based, for example, on the particle size distribution measured using dynamic light scattering (DLS), or on the nanoseed NS particle size determined based on any one of the aforementioned measurement methods.

[0132] The microseeds MS and nanoseeds NS may be provided together or simultaneously on the surface 11 of the support layer or material 3, for example, for stirring. Subsequently, the support layer or material 3 (or device 1) is rinsed and / or dried.

[0133] Alternatively, microseeds MS can be dispersed by first placing them on the surface 11 of the support layer or material 3, and then stirring. Afterward, nanoseeds NS can be dispersed by first placing them on the surface 11 of the support layer or material 3, and then stirring. Rinsing and / or drying of the support layer or material 3 (or device 1) can be performed, for example, between the dispersion of microseeds MS and the dispersion of nanoseeds NS, after the dispersion of nanoseeds NS, or only after the dispersion of nanoseeds NS. Alternatively, the dispersion of nanoseeds NS may be performed before the dispersion of microseeds MS.

[0134] The desired density can be obtained by providing microseeds (MS) and / or nanoseeds (NS) for example, only once, multiple times in succession, or in any order.

[0135] It should be noted that not all recesses 7 need to contain microseed MS and nanoseed NS; the results described herein can be obtained by using multiple recesses 7 containing microseed MS and nanoseed NS.

[0136] Accordingly, the seed dipping method of this disclosure is ensured by providing recesses 7, for example, in one or more support layers or one or more materials 3, and by diamond seeding across the inner and outer surfaces 11 of the recesses 7 in the support layers or material 3. This is done before providing or depositing the diamond layer 9 on the device 1.

[0137] The method of the present disclosure also includes, for example, a diamond growth step of depositing a diamond layer 9 onto a diamond-seeded support layer or material 3. The diamond growth step can be carried out, for example, using chemical vapor deposition (CVD), such as microwave plasma chemical vapor deposition (MPCVD), or by low-temperature plasma CVD, atmospheric plasma CVD, plasma torch, and hot filament CVD.

[0138] The diamond layer 9 includes, for example, polycrystalline and / or single-crystal diamond, or is composed of such diamond.

[0139] The method further includes, for example, a diamond polishing step of polishing the deposited diamond layer 9. Polishing of the diamond layer 9 can be carried out, for example, using chemical polishing and / or mechanical polishing.

[0140] A fine-grained diamond grinding wheel can be used, for example, for the initial high-speed material removal and planarization of the diamond layer 9. Furthermore, precision polishing can then be performed using, for example, a lapping machine designed for diamond polishing to obtain a flat, mirror-like finish, such as that shown in Figure 6D.

[0141] A polished diamond layer 9 having a surface roughness of sub-nanometers is provided, for example, using such polishing.

[0142] After polishing, the diamond layer 9 (or device 1) can be cleaned, for example, using acetone and IPA. Subsequently, further cleaning steps can be performed to remove, for example, the graphite phase, undesirable layers, and other impurities.

[0143] As described above, in the method according to this disclosure, the support layer or material 3 may include or be composed of, for example, GaN or AlGaN.

[0144] The support layer or material 3 contains or is composed of, for example, GaN and AlGaN, and the Al content increases as the thickness of the layer or material increases.

[0145] As described above, the GaN and / or AlGaN layer can be placed on, for example, a substrate 3A. The substrate 3A may include or be composed of, for example, Si (silicon), SiC (silicon carbide), GaAs, Ga2O3, borosilicate, quartz, or sapphire. The recess 7 can extend, for example, to or into the substrate.

[0146] To demonstrate the fixation and strong adhesion of diamond, and the advantages of the method and device 1 of this disclosure, the inventors present experimental results in this specification for exemplary embodiments of diamond grown on GaN and / or AlGaN, particularly diamond grown on AlGaN / GaN-on-Si substrates. However, it should be understood that this disclosure is not limited to these specific embodiments.

[0147] AlGaN / GaN-on-Si substrates were used for seed dipping and diamond growth, enabling diamond integration on GaN-on-Si HEMTs for applications such as thermal management and power electronics.

[0148] A Si substrate 3A with a GaN and / or AlGaN layer 3 deposited on it was used. The GaN and / or AlGaN layer 3 has an exemplary thickness of approximately 3 μm or 5 μm. A relatively thin buffer layer may be present directly on the Si and between the outer GaN or AlGaN layer 3. Seed dipping began with deep etching of holes 7 in the support layer / substrate before growth (step II in Figure 2(a)). The etching step of GaN3 was performed using inductively coupled plasma (ICP) etching with Cl2 / BCl3 / Ar. Subsequently, the substrate 3A was further etched using a standard Bosch Si etching process to adjust the aspect ratio of the holes 7. Here, a Si etching step was performed to form holes 7 with a high aspect ratio simply to study the effect of hole depth DP, but for the remainder of the study, an optimized depth DP that did not require a Si etching step or significant deep etching was used. SiO2 was used as a hard mask for all etching steps and was deposited at 300°C using plasma CVD (PECVD).

[0149] Subsequently, micro-seeds MS and nano-seeds NS were seeded onto substrates 3 and 3A (Step III in Figure 2(a)). First, nano-seeding was performed using a 0.5% wt suspension of 5-10 nm diamond nanoparticles NS in methanol, followed by ultrasonic stirring for 10 minutes, IPA rinsing, and nitrogen drying. Then, micro-seeding MS was performed by immersing the substrate in a 10% wt suspension of 3-4 μm undoped diamond particles in isopropanol (IPA), which was ultrasonically stirred for 10 minutes. The seed dipping method resulted in the incorporation of diamond micro-seeds MS into the patterned GaN-on-Si substrates 3 and 3A (Figure 2(b)), and large micro-seeds MS could be efficiently confined within the pores 7 (Figure 2(c)).

[0150] As shown in Figure 2(d), the diamond nanoseed NS also has high density (>10) on substrate 3, 3A. 11 cm -1 It was covered with ).

[0151] A polycrystalline diamond film 9 was grown on substrates 3 and 3A seeded by microwave plasma chemical vapor deposition (MPCVD). The substrate temperature was fixed at 850°C, the average plasma power was 4 kW, and the pressure was 130 mbar. The diamond growth rate was maintained at over 1 μm / h using high-purity gas (9N) with a standard gas ratio (95% H2, 5% CH4) and with the addition of small amounts of nitrogen and / or argon (several ppm).

[0152] The grown diamond film 9 typically has a relatively high surface roughness (step IV in Figure 2(a)), and a smooth surface can be obtained by chemical / mechanical polishing steps (step V in Figure 2(a)). For example, diamond polishing can be performed by mounting the substrates 3, 3A containing the diamond 9 to be installed on a work head and applying them to a coarse-grained horizontal diamond grinding wheel for initial high-speed material removal and planarization of the diamond. Subsequently, the substrates 3, 3A are polished using a lapping machine specially designed for diamond polishing to obtain a flat, mirror finish. After polishing, the substrates can be cleaned using acetone and IPA, followed by a cleaning step using a high-temperature H2SO4 / H2O2 mixture to remove the graphite phase and all other impurities.

[0153] Nanoseed NS provides excellent surface coverage and high seeding density, but the low thermal conductivity of nanocrystalline diamond near the interface can lead to high TBR (thermal breakdown ratio). 31 On the other hand, while microseed MS can produce large particles and high thermal conductivity, the presence of gaps between particles near the interface can expose GaN to the hydrogen plasma of a CVD reactor, potentially causing GaN etching. 32、33 The use of mixed seeds in the seed dipping method of this disclosure offers the advantages of both methods, resulting in larger particles, and therefore higher thermal conductivity, as well as lower TBR and no damage to the GaN surface. 31 .

[0154] In the seed dipping method, to optimize and investigate the size and aspect ratio of the holes 7, a seeding step was performed in holes 7 with aperture sizes varying from 4 to 50 μm and large depths (~30 μm), followed by the growth of a diamond layer 9 approximately 30 μm thick. Figures 3(a) to 3(d) show cross-sectional SEM images of holes 4 μm, 10 μm, 20 μm, and 50 μm in size, respectively.

[0155] Although all pores 7 underwent the same seeding process, the containment of microseed MS depended heavily on the pore size. Pores 7 with a diameter of 4 μm were the most efficient at capturing microseed MS (Figure 3(a)). However, pores 7 with a diameter of 10 μm captured fewer microseed MS (Figure 3(b)), and larger pores 7 captured very few microseed MS (Figures 3(c) and 3(d)).

[0156] Figure 3(e) shows that only the top 5 μm of seeds in the initial substrate contributed to diamond nucleation and growth. No diamond growth was observed beyond 5 μm, which may be due to low diffusion of carbon atoms in the pores during growth and rapid coalescence at the top that can prevent nucleation from deeper seeds. Looking more closely near the diamond / GaN interface (Figure 3(f)), it can be seen that nanoseeds NS acted as nucleation sites for conformal growth of the diamond layer 9 with good adhesion to substrates 3, 3A, while microseeds MS formed nucleation sites for larger diamond crystals, contributing to a higher average grain size and higher quality of the polycrystalline diamond film 9. The growth of diamond 9 in all other pore sizes was mainly due to the presence of nanoseeds NS, with very few microseeds MS contributing to the growth of larger particles.

[0157] The size of the pores 7 did not affect the thickness of the diamond 9, but it significantly affected the roughness of the final diamond film 9. Insufficient diamond coalescence on 50 μm pores resulted in the formation of depressions at the top of pores 7 deeper than 10 μm (Figure 3(d)). Coalescence was significantly improved with smaller pores 7, and the depressions were much smaller. In samples with 10 μm and 20 μm pores 7, coalescence created cavities embedded within the pores 7 (Figures 3(b) and 3(c)), and the coalescence interface was visible along the entire thickness of the diamond film 9. However, in 4 μm pores 7, the coalescence interface was barely visible, with only diamond particles visible, indicating much improved coalescence.

[0158] Therefore, the size of an exemplary optimized pore 7 that incorporates both microseed MS and nanoseed NS and contributes to growth was found to be a width WD of 4 μm and a depth DP of 5 μm, which (approximately) corresponds to the average diameter of the microseed MS used in this study (e.g., D50 median diameter) (3-4 μm). Such a depth avoids deeper etching and simplifies the fabrication method. However, deeper depths are also possible if one or more microseed MS are located at the upper level (upper enclosure) of the recess 7, for example, within a depth DP of 5 μm from the opening OP of the pore 7.

[0159] Based on these results, AlGaN / GaN-on-Si substrates were constructed with these dimensions for the following experiments. The seed dipping method enabled reliable and reproducible growth of thick diamond layers on AlGaN / GaN-on-Si, including diamond layers thicker than 100 μm (20 hours of growth), without any signs of film delamination or cracking (Figure 4(a)). The diamonds grown from nanoseeds NS filled the space between the microseeds MS and the sidewalls (inset in Figure 4(a)), which significantly improved the adhesion of diamonds to substrates 3 and 3A.

[0160] X-ray tomography (XRT) images of the substrate show complete diamond growth and coalescence within and on the dipping region, resulting in a uniform diamond layer 9 in which all seed MS and NS contribute to gap- or cavity-free growth (Figure 4(b)). Furthermore, embedded diamond columns are formed in the substrate, significantly improving adhesion to the substrate and shear strength at the interface.

[0161] In the seed dipping method, the presence of pores 7 in substrates 3 and 3A strongly affected the adhesion and residual stress of the grown diamond film 9. The inventors confirmed that in substrates 3 and 3A without seed dipping, even when using a SiN or AlN intermediate layer, the diamond film 9 either peeled off during cooling in the CVD reactor or developed large cracks during the subsequent fabrication process. However, microstructuring substrates 3 and 3A along with the seed dipping method significantly improved the adhesion of the diamond film even in small areas of substrates 3 and 3A, and peeling or cracking was no longer observed.

[0162] To evaluate the effect of the seeding method used in the seed dipping process on the quality of the diamond film 9, different substrates 3 and 3A were seeded using nanoseed NS, microseed MS, and a mixture of both, followed by 10 hours of diamond growth (16 μm thickness). Micro-Raman spectroscopy was used to measure the stress, phase purity, and crystal quality of the diamond 9, and by varying the focus of the incident beam within the film, Raman shift profiles along the diamond thickness were obtained. 34 .

[0163] The Raman peak of stress-free diamond film 9 is 1332 cm⁻¹. -1 However 35 The values ​​were slightly higher in all of the above samples, which corresponds to the compressive stress of diamond 9. The stress profiles were calculated based on the positive shift of the peaks (Figure 5(a)). 36 The highest stress was measured only in samples containing nanoseeds at the interface with GaN (1.1 GPa), which is significantly lower than the typical values ​​measured for diamond films grown at over 700°C on GaN-on-Si film structures (5.6 GPa and 23.6 GPa depending on the dimensions). 20This may be due to dipping of substrates 3 and 3A. As it moved towards the upper diamond surface, the stress gradually decreased to 0.6 GPa. Diamond films 9, including micro-seed MS and mixed seeding, showed much lower stress at the interface, at 0.35 GPa and 0.2 GPa, respectively. Small changes were observed near the top surface (>12 μm thickness), which may be due to small changes in reactor parameters during growth. Such results highlight the significant advantage of seed dipping combined with mixed seeding for obtaining low residual stress in diamond, which is important to avoid delamination and cracking of the film.

[0164] All diamond films 9 have a thickness exceeding 8 μm and a high phase purity of 80% to 95% (sp 3 / sp 2 The ratio shows a low graphite phase of carbon atoms and high crystalline quality of diamond (Figure 5(b)). 3 / sp 2 The ratio was observed across the entire thickness of the substrate containing nanoseeds NS. However, lower ratios of 45% and 70%, respectively, were observed at the diamond / GaN interface containing microseeds and mixed seeds. Nevertheless, the phase purity of these films increased rapidly with increasing film thickness, saturating at maximum values ​​above 8 μm.

[0165] The high crystalline quality of the diamond film 9 was verified by the full width at half maximum (FWHM) of the Raman peak. The Raman spectrum of natural diamond is approximately 2 cm. -1 Although it has FWHM, polycrystalline CVD films generally have a wider width (5-15 cm) depending on the amount of crystal disorder caused by defects or strain. -1 ) indicates 37 As shown in Figure 5(c), a decrease in FWHM from the interface towards the top surface corresponds to higher film quality. Mixed seeds generally showed the lowest FWHM, and therefore the best crystal quality.

[0166] The X-ray photoelectron spectroscopy (XPS) spectrum in Figure 5(d) shows a strong peak for C1s and a very small peak for O1s. Analysis of the XPS spectrum revealed a very high-purity diamond film containing 98.27% carbon, 0.27% nitrogen, and 1.46% oxygen, spontaneously absorbed at the surface.

[0167] In a seed dipping method using mixed seeds, growth initiated by micro-seeds (MS) resulted in particles much larger than those grown by nano-seeds (NS) (Figure 5(e)). This higher average particle size is a significant advantage, as it reduces the thermal resistance within the particles, dramatically improving the thermal conductivity of films of the same diamond thickness. 3、38、39 Due to the random orientation and size variations of the diamond particles, the grown diamond film 9 exhibited a rough surface with a roughness of several tens of microns (Figure 6(a)). Such roughness is a problem for wafer processing. Therefore, the diamond film 9 requires a polishing step, which was previously difficult due to the high residual stress and weak adhesion of diamond films deposited using conventional methods. However, here, polishing of the diamond film 9 was made possible by the main improvement achieved by the seed dipping method. The presence of large micro-seeds MS in the pores 7, and the adhesion of the micro-seeds MS to the sidewalls by nano-seeds NS, forms diamond columns embedded in the substrates 3, 3A (Figure 4(b)), which can act as anchors that increase the shear strength at the interface with the substrates 3, 3A. In addition, the low residual stress gave the diamond film 9 excellent stability to maintain the mechanical polishing step (Figure 6(b)).

[0168] After precision polishing of substrates 3 and 3A containing the diamond layer 9 using a lapping machine, the high-quality diamond film 9 exhibited a transparent surface. Atomic force microscopy (AFM) scanning of areas exceeding 30 μm × 30 μm revealed sub-nanometer roughness, including an arithmetic mean roughness (Ra) of 0.5 nm and a root mean square roughness (Rq) of 0.6 nm (Figure 6(c)). The seed dipping method enabled reliable growth and polishing of diamond on AlGaN / GaN substrates with reproducible high quality (Figure 6(d)). Neither the Raman spectrum nor the FWHM showed any change after polishing, indicating that the high quality of the diamond was maintained after polishing (Figure 6(d)).

[0169] This specification describes a seed dipping method for diamond seeding and growth on other substrates such as AlGaN / GaN-on-Si, using intentional microstructural configurations of substrates 3 and 3A, and diamond seeding with both micro-seeds MS and nano-seeds NS. The configuration of pores 7 was optimized to efficiently confine the micro-seeds and allow both seed types to contribute to diamond growth, resulting in a complete cohesive without cavity formation. In addition, the diamond columns formed within pores 7 by the growth of nano-seeds NS adhering the micro-seeds MS to the sidewalls resulted in excellent diamond adhesion to the substrate and high shear strength at the interface.

[0170] The material properties of the diamond film 9 grown using seed dipping showed better crystallinity and larger grain size compared to conventional nanoseeding methods. The growth method of this disclosure has more than 98% carbon atoms and a high sp² of 95%. 3 / sp 2This resulted in a high-purity diamond film 9 with a specific ratio. The low residual stress (0.2 GPa), excellent adhesion to substrates 3 and 3A, and high mechanical stability of the diamond film 9 obtained by seed dipping enabled reliable and reproducible diamond growth on GaN, followed by a polishing step to obtain a smooth diamond surface with a roughness of less than 1 nm. The developed polished diamond-on-GaN substrate may be a cost-effective method for developing integrated heat spreaders, power ICs using complementary switches, and novel heterostructure devices that combine the properties of diamond and GaN.

[0171] While the present invention has been disclosed with reference to certain preferred embodiments, many modifications, alterations, and changes are possible to the embodiments described and their equivalents without departing from the art and scope of the invention. Therefore, the present invention is not limited to the embodiments described, and the broadest reasonable interpretation is intended in accordance with the language of the appended claims. Features of any one of the above embodiments may be included in other embodiments described herein.

[0172] (References) (1) Koizumi, S.; Umezawa, H.; Pemot, J.; Suzuki, M. Power Electronics Device Applications of Diamond Semiconductors, Woodhead Publishing Series in Electronic and Optical Materials; Elsevier Science, 2018. https: / / doi.org / 10.1016 / c2016-0-03999-2. (2) Amano, H.; Baines, Y.; Beam, E.; Borga, M.; Bouchet, T.; Chalker, P.R.; Charles, M.; Chen, K.J.; Chowdhury, N.; Chu, R.; De Santi, C.; De Souza, M.M.; Decoutere, S.; Di Cioccio, L.; Eckardt, B.; Egawa, T.; Fay, P.; Freedsman, J.J.; Guido, L.; Haberlen, O.; Haynes, G.; Heckel, T.; Hemakumara, D.; Houston, P.; Hu, J.; Hua, M.; Huang, Q.; Huang, A.; Jiang, S.; Kawai, H.; Kinzer, D.; Kuball, M.; Kumar, A.; Lee, K.B.; Li, X.; Marcon, D.; Marz, M.; McCarthy, R.; Meneghesso, G.; Meneghini, M.; Morvan, E.; Nakajima, A.; Narayanan, E. M. S.; Oliver, S.; Palacios, T.; Piedra, D.; Plissonnier, M.; Reddy, R.; Sun, M.; Thayne, L.; Torres, A.; Trivellin, N.; Unni, V.; Uren, M. J.; Van Hove, M.; Wallis, D. 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Claims

1. A support layer or material (3) comprising at least one support layer or material (3) containing at least one or more support structures (5), A plurality of recesses (7) defined by at least one or more of the support structures (5), Each recess (7) or the plurality of recesses (7) contains at least one diamond microseed (MS) and a plurality of diamond nanoseeds (NS) A diamond device or structure (1) comprising:

2. The diamond device or structure (1) according to claim 1, wherein the at least one or more support structures (5) define the openings (OP) and upper enclosures (UE) of each recess (7) or the plurality of recesses (7), and the at least one diamond microseed (MS) is disposed within the openings (OP) and / or the upper enclosures (UE).

3. The diamond device or structure (1) according to claims 1 and 2, wherein the at least one diamond microseed (MS) has a size or diameter (DD) that is 40% to 95%, 60% to 95%, 75% to 95%, or 75% to 90% of the size or diameter of the opening (OP).

4. The diamond device or structure (1) according to any one of claims 1 to 3, wherein the at least one diamond microseed (MS) defines a nucleation site or accretion site for diamond crystal growth.

5. The diamond device or structure (1) according to any one of claims 2 to 4, wherein the opening (OP) and / or the upper enclosure (UE) comprises a plurality of dispersed diamond nanoseeds (NS).

6. The diamond device or structure (1) according to claim 5, wherein the diamond nanoseeds (NS) define nucleation sites for conformal diamond growth.

7. The diamond device or structure (1) according to any one of claims 1 to 6, wherein each recess (7) or the plurality of recesses (7) is defined by at least one wall (W) and at least one floor (FL), and a plurality of diamond nanoseeds (NS) are arranged on the at least one wall (W) and / or the at least one floor (FL).

8. The diamond device or structure (1) according to claim 7, wherein the at least one wall (W) completely encloses the at least one diamond microseed (MS), and the at least one diamond microseed (MS) is completely or partially located within the at least one wall (W).

9. The diamond device or structure (1) according to any one of claims 1 to 8, wherein each recess or the plurality of recesses (7) has a depth (DP), and the depth (DP) of the recess (7) is 60% to 1000%, 60% to 500%, 80% to 150%, or 100% to 120% of the size or diameter (DD) of the at least one diamond microseed (MS).

10. The diamond device or structure (1) according to any one of claims 1 to 9, wherein the upper enclosure (UE) comprises only one diamond microseed (MS).

11. A diamond device or structure (1) according to any one of claims 1 to 8, wherein a plurality of diamond microseeds (MS) are arranged in each recess (7) or the plurality of recesses (7), and the diamond microseeds (MS) are stacked to fill each recess (7) or the plurality of recesses (7).

12. The diamond device or structure (1) according to claim 11, wherein the diamond microseeds (MS) are stacked so as to extend to each recess (7) or to the upper enclosure (UE) of the plurality of recesses (7).

13. The diamond device or structure (1) according to claim 11 or 12, wherein the diamond microseeds (MS) are stacked so as to extend to a position within at least 60%, 40%, 20%, 15%, 10%, or 5% of the outer edge (RM) of the opening (OP) of the recess (7), or to a position within or surrounded by the outer edge (RM) of the opening (OP).

14. The diamond device or structure (1) according to any one of claims 11 to 13, wherein the diamond microseeds (MS) are stacked from the floor (FL) of the recess (7).

15. The diamond device or structure (1) according to any one of claims 2 to 14, wherein the at least one or more support structures (5)) include a first wall (FW), a second wall (SW), and an upper landing (UL) extending between the first wall (FW) and the second wall (SW), and a plurality of diamond nanoseeds (NS) are arranged or dispersed on the upper landing (UL) and the first wall (FW) and the second wall (SW).

16. The diamond device or structure (1) according to claim 15, wherein the at least one or more support structures (5) include a plurality of walls (W) and a plurality of upper landings (UL) extending between the walls (W), and a plurality of diamond nanoseeds (NS) are arranged or dispersed in the upper landings (UL) and the walls (W).

17. The diamond device or structure (1) according to any one of claims 1 to 16, wherein the at least one diamond microseed (MS) comprises or is composed of particles or chips having a diameter or size (DD) of 1 μm to 2000 μm, 1 μm to 500 μm, 1 μm to 250 μm, 1 μm to 100 μm, 1 μm to 50 μm, or 3 μm to 7 μm.

18. The diamond device or structure (1) according to any one of claims 1 to 17, wherein the diamond nanoseeds (NS) include or are composed of particles having a diameter or size of 1 nm to less than 1000 nm, or 1 nm to 200 nm, or 1 nm to 100 nm, or 1 nm to 50 nm, or 1 nm to 15 nm, or 4 nm to 11 nm.

19. The diamond nanoseeds (NS) are dispersed or attached to the surface of the at least one support layer or material (3) at a density of 10 ８ cm －２ -2 to 10 １４ cm －２ -2, or 10 ８ cm －２ -3 to 10 １３ cm －２ -2, or 10 ９ cm －２ -4 to 10 １３ cm －２ -2, or 10 ９ cm －２ -5 to 10 １２ cm －２ -2. The diamond device or structure (1) according to any one of claims 1 to 18.

20. The diamond device or structure (1) according to any one of claims 1 to 19, wherein the one or more recesses (7) have an opening width (WD) in the planar direction of the at least one support layer or material (3), and the opening width has a value of 1 μm to 2000 μm, or 1 μm to 500 μm, or 1 μm to 250 μm, or 1 μm to 100 μm, or 1 μm to 50 μm, or 4 μm to 15 μm, or 3 μm to 6 μm.

21. The diamond device or structure (1) according to any one of claims 1 to 20, wherein the one or more recesses (7) have a depth (DP) extending in a direction perpendicular to the planar direction of the at least one support layer or material (3), and the depth has a value of 2 μm to 1000 μm, 2 μm to 400 μm, 2 μm to 100 μm, 2 μm to 20 μm, or 2 μm to 5 μm.

22. The diamond device or structure (1) according to any one of claims 1 to 21, wherein the plurality of recesses (7) are arranged in at least one or more regions of the at least one support layer or material (3), or the plurality of recesses (7) are arranged over the entirety of the at least one support layer or material (3).

23. The diamond device or structure (1) according to any one of claims 1 to 22, wherein the plurality of recesses (7) are configured as a periodic recess array, or arranged in a periodic array arrangement across the at least one support layer or material (3), or arranged as a non-periodic recess array.

24. The diamond device or structure (1) according to any one of claims 1 to 23, further comprising a diamond layer (9) attached to the at least one support layer or material (3).

25. The diamond device or structure (1) according to any one of claims 1 to 24, further comprising a diamond layer (9) or polished diamond layer (9) directly attached to the at least one support layer or material (3).

26. The diamond device or structure (1) according to claim 24 or 25, wherein the diamond microseeds (MS) are arranged in the plurality of recesses (7), and the diamond nanoseeds (NS) are dispersed on the at least one support layer or material (3) and in the plurality of recesses (7) to chemically bond and / or mechanically fix or fix the diamond layer (9) to the at least one support layer or material (3).

27. The diamond device or structure (1) according to any one of claims 24 to 26, wherein the diamond layer (9) extends from the diamond microseeds (MS) of the openings (OP) of the plurality of recesses (7) and / or the upper enclosure (UE).

28. The diamond device or structure (1) according to any one of claims 24 to 27, wherein the diamond layer (9) extends only from the diamond microseeds (MS) of the openings (OP) of the plurality of recesses (7) and / or the upper enclosure (UE).

29. The diamond device or structure (1) according to any one of claims 24 to 28, wherein there is no diamond growth in each recess (7) or in the lower enclosure (LE) of the plurality of recesses (7).

30. The diamond device or structure (1) according to any one of claims 24 to 29, wherein the diamond layer (9) has a thickness of >6 μm.

31. The diamond device or structure (1) according to any one of claims 24 to 30, wherein both the diamond microseed (MS) and the diamond nanoseed (NS) define nucleation sites or coalescence sites for diamond crystal growth in the at least one support layer or material (3).

32. The diamond device or structure (1) according to any one of claims 24 to 31, wherein the diamond layer (9) is a polished diamond layer (9).

33. The diamond device or structure (1) according to claim 32, wherein the polished diamond layer (9) has a surface roughness of nanometers or sub-nanometers.

34. The diamond device or structure (1) according to any one of claims 24 to 33, wherein the diamond layer (9) is a high-purity diamond layer containing at least 98% carbon atoms.

35. The diamond device or structure (1) according to any one of claims 24 to 34, wherein the diamond device or structure (1) has no intermediate layer between the diamond layer (9) and the at least one support layer or material (3).

36. The diamond device or structure (1) according to claim 35, wherein the diamond device or structure (1) has no AlN intermediate layer, no SiN intermediate layer, or no SiC intermediate layer between the diamond layer (9) and the at least one support layer or material (3).

37. The diamond device or structure (1) according to any one of claims 1 to 36, wherein the diamond device or structure (1) includes a plurality of support layers or materials (3), and the at least one or more support structures (5) are disposed within the plurality of support layers or materials (3).

38. The diamond device or structure (1) according to claim 37, wherein the plurality of recesses (7) extend through the plurality of support layers or materials (3).

39. A diamond device or structure (1) according to any one of claims 1 to 38, comprising a substrate (3A) and at least one or more support layers or materials (3) attached to the substrate (3A).

40. The diamond device or structure (1) according to claim 39, wherein the at least one or more support structures (5) are arranged within the at least one layer (3) or the multiple layers (3), or within the at least one layer or the multiple layers (3) and the substrate (3A).

41. The diamond device or structure (1) according to claim 39 or 40, wherein the plurality of recesses (7) extend through only the at least one or plurality of layers (3) attached to the substrate (3A), or extend into the substrate (3A) through the at least one or plurality of layers (3) attached to the substrate (3A).

42. The diamond device or structure (1) according to any one of claims 1 to 41, wherein the at least one support layer or material (3) includes or is composed of GaN or AlGaN.

43. A diamond device or structure (1) according to any one of claims 1 to 42, comprising a substrate (3A) wherein the at least one support layer or material (3) is disposed on the substrate (3A).

44. A diamond device or structure (1) according to any one of claims 1 to 43, comprising a substrate (3A) and a GaN and / or AlGaN layer disposed on the substrate (3A).

45. The diamond device or structure (1) according to claim 43 or 44, wherein the plurality of recesses (7) extend to or into the substrate (3A).

46. The substrate (3A) is made of Si, SiC, GaAs, Ga ２ O ３ A diamond device or structure (1) according to any one of claims 42 to 44, comprising or composed of a borosilicate, quartz, or sapphire.

47. An electronic device or integrated circuit comprising a diamond device or structure (1) according to any one of claims 1 to 46.

48. A step of providing at least one support layer or material (3) which includes at least one or more support structures (5) within at least one support layer or material (3), and a plurality of recesses (7) defined by the at least one or more support structures (5), The steps include performing diamond seeding to provide at least one diamond microseed (MS) and a plurality of diamond nanoseeds (NS) in each recess (7) or the plurality of recesses (7), and A method for manufacturing a diamond device or structure (1) including the following.

49. The step of providing the at least one support layer or material (3) including at least one support structure (5) and a plurality of recesses (7) is, The steps include providing at least one support layer or material (3), The steps include etching the at least one support layer or material (3) to form a plurality of recesses (7) within the at least one support layer or material (3), and The method according to claim 48, including the method described in claim 48.

50. The method according to claim 48 or 49, wherein each recess (7) or the plurality of recesses (7) is defined by at least one wall (W) and at least one floor (FL), and the at least one wall (W) extends to define a completely enclosing wall (W) for fully or partially receiving the at least one diamond microseed (MS) within the at least one wall (W).

51. The method according to any one of claims 48 to 50, wherein the one or more recesses (7) have an opening width (WD) in the planar direction of the at least one support layer or material (3), and the opening width has a value of 1 μm to 2000 μm, or 1 μm to 500 μm, or 1 μm to 250 μm, or 1 μm to 100 μm, or 1 μm to 50 μm, or 4 μm to 15 μm, or 3 μm to 8 μm, and / or the one or more recesses (7) have a depth (DP) extending in a direction perpendicular to the planar direction of the at least one support layer or material (3), and the depth has a value of 2 μm to 1000 μm, or 2 μm to 300 μm, or 2 μm to 100 μm, or 2 μm to 50 μm, or 2 μm to 15 μm,

52. The method according to any one of claims 48 to 51, wherein the plurality of recesses (7) are arranged in at least one or more regions of the at least one support layer or material (3), or the plurality of recesses (7) are arranged over the entirety of the at least one support layer or material (3).

53. The diamond device or structure (1) according to any one of claims 1 to 52, wherein the plurality of recesses (7) are configured as a periodic recess array, or arranged in a periodic array arrangement across the at least one support layer or material (3), or arranged as a non-periodic recess array.

54. The step of performing diamond seeding is The steps include: placing microseeds (MS) on the surface of the at least one support layer or material (3), stirring the at least one support layer or material (3) to move the microseeds (MS) into each recess (7) or into the plurality of recesses (7); The steps include: placing nanoseeds (NS) on the surface of the at least one support layer or material (3); stirring the at least one support layer or material (3) to disperse the nanoseeds (NS) within each recess (7) or the plurality of recesses (7) and across the surface of the at least one support layer or material (3); The method according to any one of claims 48 to 53, including the method described in any one of claims 48 to 53.

55. The method according to claim 54, wherein the microseeds (MS) and nanoseeds (NS) are provided together, continuously, and / or multiple times on the surface of the at least one support layer or material (3) for stirring.

56. The method according to claim 55, further comprising the step of rinsing and / or drying.

57. The method according to any one of claims 48 to 56, wherein the diamond microseed (MS) comprises or is composed of particles or chips having a diameter or size (DD) of 1 μm to 1000 μm, 1 μm to 500 μm, 1 μm to 250 μm, 1 μm to 100 μm, 1 μm to 50 μm, or 3 μm to 7 μm.

58. The method according to any one of claims 48 to 57, wherein the diamond nanoseeds (NS) include or consist of particles having a diameter or size of 1 nm to less than 1000 nm, or 1 nm to 200 nm, or 1 nm to 100 nm, or 1 nm to 50 nm, or 1 nm to 10 nm, or 3 nm to 15 nm, or 5 nm to 10 nm.

59. The aforementioned diamond nanoseed (NS) > 10 ８ cm －２ The method according to any one of claims 48 to 58, wherein the material is dispersed or attached to the surface of the at least one support layer or material (3) at a density of .

60. The method according to any one of claims 48 to 59, wherein the at least one or more support structures (5) define an opening (OP) and an upper enclosure (UE) of each recess (7) or the plurality of recesses (7), and at least one diamond microseed (MS) is disposed within the opening (OP) and / or the upper enclosure (UE).

61. The method according to claim 60, wherein the diamond microseed (MS) has a size or diameter (DD) that is 40% to 95% or 75% to 95% of the size or diameter of the opening (OP).

62. The method according to any one of claims 48 to 61, wherein the at least one diamond microseed (MS) defines a nucleation site or accretion site for diamond crystal growth.

63. The method according to any one of claims 60 to 62, wherein the upper enclosure (UE) comprises a plurality of dispersed diamond nanoseeds (NS).

64. The method according to claim 63, wherein the diamond nanoseed (NS) defines the nucleation site for conformal diamond growth.

65. The method according to any one of claims 48 to 64, wherein each recess (7) or the plurality of recesses (7) is defined by at least one wall (W) and at least one floor (FL), and a plurality of diamond nanoseeds (NS) are arranged on the at least one wall (W) and / or the at least one floor (FL).

66. The diamond device or structure (1) according to any one of claims 48 to 65, wherein each recess or the plurality of recesses (7) has a depth (DP), and the depth (DP) of the recess (7) is 60% to 150%, 60% to 120%, or 60% to 100% of the size or diameter (DD) of the at least one diamond microseed (MS).

67. The diamond device or structure (1) according to any one of claims 1 to 66, wherein the upper enclosure (UE) comprises only one diamond microseed (MS).

68. The method according to any one of claims 48 to 65, wherein a plurality of diamond microseeds (MS) are arranged in each recess (7) or in the plurality of recesses (7), and the diamond microseeds (MS) are stacked to fill each recess (7) or the plurality of recesses (7).

69. The method according to any one of claims 46 to 69, wherein the diamond microseeds (MS) are stacked so as to extend to each recess (7) or to the upper enclosure (UE) of the plurality of recesses (7).

70. The method according to claim 69 or 70, wherein the diamond microseeds (MS) are stacked to a position within at least 60%, 40%, 20%, 15%, 10%, or 5% of the outer edge (RM) of the opening (OP) of the recess (7), or to a position within or surrounded by the outer edge (RM) of the opening (OP).

71. The method according to any one of claims 69 to 71, wherein the diamond microseeds (MS) are stacked from the floor (FL) of the recess (7).

72. The method according to any one of claims 58 to 67, wherein the at least one or more support structures (5) include a first wall (FW), a second wall (SW), and an upper landing (UL) extending between the first wall (FW) and the second wall (SW), and a plurality of diamond nanoseeds (NS) are arranged or dispersed on the upper landing (UL) and the first wall (FW) and the second wall (SW).

73. The method according to claim 72, wherein the at least one or more support structures (5) include a plurality of walls (W) and a plurality of upper landings (UL) extending between the walls (W), and a plurality of diamond nanoseeds (NS) are arranged or dispersed in the upper landings (UL) and the walls (W).

74. The method according to any one of claims 48 to 74, further comprising a diamond growth step of depositing a diamond layer (9) onto the diamond-seeded support layer or material (3).

75. The method according to claim 74, wherein the diamond growth step is performed using chemical vapor deposition (CVD).

76. The method according to claim 75, wherein the diamond microseeds (MS) are arranged in the plurality of recesses (7), and the diamond nanoseeds (NS) are dispersed on the at least one support layer or material (3) and in the plurality of recesses (7) to chemically bond and / or mechanically fix or fix the diamond layer (9) to the at least one support layer or material (3).

77. The method according to claim 76, wherein the diamond layer (9) is a polycrystalline or single-crystal diamond layer (9).

78. The method according to any one of claims 48 to 78, further comprising a diamond polishing step of polishing the diamond layer (9).

79. The method according to claim 78, wherein the step of polishing the diamond layer (9) is performed using chemical polishing and / or mechanical polishing.

80. The method according to claim 79, wherein the step of polishing the diamond layer (9) is performed to provide a polished diamond layer (9) having a surface roughness of nanometers or sub-nanometers.

81. The step of providing the at least one support layer or material (3) is, The steps include providing multiple support layers or materials (3), The steps include etching the plurality of support layers or materials (3) to form a plurality of recesses (7) within the plurality of support layers or materials (3), and The method according to any one of claims 48 to 81, including the method described in any one of claims 48 to 81.

82. The step of providing the at least one support layer or material (3) is, The steps include providing a substrate (3A) and at least one or more layers (3) attached to the substrate (3A), The steps include etching the at least one or more layers (3) attached to the substrate (3A) to form a plurality of recesses (7) only within the at least one or more layers (3), or within the at least one or more layers (3) and the substrate (3A), and The method according to any one of claims 48 to 82, including the method described in any one of claims 48 to 82.

83. The method according to any one of claims 48 to 83, wherein the at least one support layer or material (3) includes or is composed of GaN or AlGaN.

84. The method according to any one of claims 48 to 84, wherein a substrate (3A) and at least one layer (3) disposed on the substrate are provided.

85. The method according to any one of claims 8 to 85, wherein a substrate (3A) and a GaN and / or AlGaN layer (3) disposed on the substrate (3A) are provided.

86. The method according to any one of claims 83 to 86, wherein the plurality of recesses (7) extend to or into the substrate (3A).

87. The substrate (3A) is made of Si, SiC, GaAs, Ga ２ O ３ The method according to any one of claims 83 to 87, comprising or composed of a borosilicate, quartz, or sapphire.

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