GB2528638A - Post-synthesis processing of diamond and related super-hard materials - Google Patents
Post-synthesis processing of diamond and related super-hard materials Download PDFInfo
- Publication number
- GB2528638A GB2528638A GB1410848.4A GB201410848A GB2528638A GB 2528638 A GB2528638 A GB 2528638A GB 201410848 A GB201410848 A GB 201410848A GB 2528638 A GB2528638 A GB 2528638A
- Authority
- GB
- United Kingdom
- Prior art keywords
- super
- hard material
- processing
- processing surface
- measured
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
- B24D3/02—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
- B24D3/20—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially organic
- B24D3/28—Resins or natural or synthetic macromolecular compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
- B24D18/0072—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for using adhesives for bonding abrasive particles or grinding elements to a support, e.g. by gluing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
Abstract
A method suitable for processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2 comprises forming a processing surface 2 by adhering abrasive particles 4 to a carrier substrate 6, preparing the processing surface 2 by removing sharp edges from the abrasive particles 4 forming a blunted processing surface 10, placing a surface of the super-hard material 14 in contact with the blunted processing surface 10 and polishing with the blunted processing surface 10. The abrasive particles 4 may be adhered to the carrier substrate 6 by embedding them in a layer of resin 8. The processing surface 2 may be prepared by using mechanical wear which may be achieved by polishing another super-hard material 12. The blunted processing surface 10 may have a lower surface roughness than before it was blunted. The super-hard material 14 may be a diamond, cubic boron nitride (CBN) or sapphire. The processed super-hard material 14 may have a low level of surface and sub-surface crystal damage, for example a low level of micro-cracks.
Description
POST-SYNTHESIS PROCESSING OF DIAMOND AND RELATED SUPER-HARD
MATERIALS
Field of Invention
The present invention relates to post-synthesis processing of diamond and related super-hard materials.
Background of Invention
In the context of the present invention super-hard materials are defined as those materials having a Vickers hardness of no less than 2000 kg/mm2. These materials include a range of diamond materials, cubic boron nitride materials (cBN), sapphire, and composites comprising the aforementioned materials, For example, diamond materials include chemical vapour deposited (CVD) single crystal and polycrystalline synthetic diamond materials of a variety of grades, high pressure high temperature (HPHT) synthetic diamond materials of a variety of grades, natural diamond material, and diamond composite materials such as polycrystalline diamond which includes a metal binder phase (PCD) or silicon cemented diamond (ScD) which includes a siliconlsilicon carbide binder phase.
In relation to the above, it should be noted that while super-hard materials are exceedingly hard, they are generally very britfie and have low toughness. As such, these materials are notoriously difficult to process into a product after the raw material is synthesized. Any processing method must be sufficiently aggressive to overcome the extreme hardness of the super-hard material while at the same time must not impart a large degree of stress or thermal shock to the material which would cause macroscopic fracturing of the material due to its brittle nature and low toughness. Furthermore, for certain applications it is important that surface and sub-surface damage at a microscopic scale, such as microcracking, is minimized to avoid deterioration of ifinctional properties which may result from such surface and sub-surface damage including, for example, optical scattering, increased optical absorption, decreased wear resistance, and increased internal stress resulting in a decrease in coherence time for quantum spin defects near the processed surface.
There is narrow operating window for achieving successful processing of super-hard materials and many available processing methods fall outside this operating window. For example, most processing methods are not sufficiently aggressive to process super-hard :i.
materials to any significant extent in reasonable time-frames. Conversely, more aggressive processing techniques tend to impart too much stress and/or thermal shock to the super-hard material thus causing cracking and material damage or failure.
Certain processing methods have operational parameters which can be altered so as to move from a regime in which no significant processing of a super-hard material is achieved into a regime in which processing is achieved but with associated cracking and damage or failure of the super-hard material. In this case, there may or may not be a transitional window of parameter space in which processing can be achieved without cracking and damage or failure of the super-hard material. The ability to operate within a suitable window of parameter space in which processing can be achieved without cracking and damage or failure of the super-hard material will depend on the processing technique, the size of any transitional operating window for such a technique, and the level of operation parameter control which is possible to maintain processing within the window of parameter space in which processing can be achieved without cracking and damage or failure of the super-hard material.
In light of the above, it will be appreciated that post-synthesis processing of super-hard materials is not a simple process and, although a significant body of research has been aimed at addressing this problem, current processing methods are still relatively time consuming and expensive, with processing costs accounting for a significant proportion of the production costs of super-hard material products.
Post synthesis processing may comprise one or more of the following basic processes: surface processing to remove material from the surface of the as-grown super-hard material in order to increase surface flatness, decrease surface roughness, remove surface defects, and/or attain a target thickness for the super-hard material; surface processing to achieve a fine surface finish where minimal material is removed from the super-hard product, i.e. polishing; and cutting of the super-hard material into target shapes arid sizes for particular product application.
In principle there are two basic forms of mechanical surface processing: (i) a two-body process in which abrasive particles are embedded/fixed in one body which is moved against a second body to process the second body; and (ii) a three-body process in which one body is moved relative to a second body to be processed and free abrasive particles, constituting a third body, are disposed between the first and second bodies in order to achieving surface processing of the second body.
The latter three-body approach to surface processing is known as lapping and it is this approach which is conventionally used to remove macroscopic quantities of surface material from super-hard materials. Three-body lapping, as opposed to a two-body surface processing technique, is preferred for removing macroscopic quantities of surface material from super-hard materials as it has been found that lapping is more efficient at removing surface material from a super-hard material without imparting a large degree of stress or thermal shock to the material which would cause macroscopic fracturing of the material due to its brittle nature and low toughness. In contrast, when it is desired to achieve a fine surface finish without removing macroscopic quantities of material then a two-body processing technique may be utilized. As such, conventionally lapping is used to remove material from the surface of an as-grown super-hard material in order to increase surface flatness, decrease surface roughness, remove surface defects, and/or attain a target thickness for the super-hard material. Subsequently, if a finc surfacc finish is required, thc supcr-hard material is polished and this may be performed using a two-body surface processing technique in which abrasive material is fixed in a polishing wheel such as via resin bonding. Polishing may also be achieved using an iron or steel wheel which is diamond impregnated and this is known as scaife polishing. Although scaife polishing generally utilizes free diamond abrasive particles these are of a small size relative to pores within the iron or steel wheel and are thus embedded/fixed into the wheel thus effecting a two-body processing as opposed to a true three body lapping process.
The most appropriate surface processing technique will depend on the end application, the type of surface finish required for the end application, and commercial considerations including an evaluation of the cost of a particular processing technique versus the commercial value of the product obtain after such processing. Surface processing parameters of interest may include one or more of roughness; flatness; curvature; surface/sub-surface crystal damage; speed; cost; precision; and repeatability.
Prior to discussing embodiments of the invention in more detail, it may be pertinent to clarify the distinction between flatness and roughness, particularly in the context of synthesis and processing of super-hard materials such as synthetic diamond materials. In this regard, a skilled person will understand that flatness and roughness are two different characteristics of a surface and particular applications will be sensitive to either one or both of these characteristics, For example, a smooth curved surface has low roughness but it not flat as illustrated in Figure 1 whereas a rough non-curved surface may be flat but have a high degree of roughness as illustrated in Figure 2. Roughness is generally the deviation of a surface from a smooth target profile measured on a microscopic scale relative to the scale of the surface area whereas flatness is generally the deviation of a surface from a smooth target profile measured on a macroscopic scale relative to the scale of the surface area, The two parameters are thus distinguished by the method of measuring deviations from a smooth surface profile with roughness being measured by a technique which determines deviations from the smooth surface profile at a microscopic scale and flatness/curvature being measured by a technique which determines deviations from a smooth surface profile at a macroscopic scale. For a wafer of material having two opposing surfaces then surface parallelism may often also be an important additional parameter.
In light of the above, it will be evident that a surface which has low roughness may still deviate significantly from a smooth target profile due to macroscopic deviations from the smooth target profile. For example, Figure 3 shows a schematic illustration of a wafer of super-hard material which has a surface profile which is bowed from a targeted smooth fiat configuration. Furthermore, if the target profile is flat then a low surface roughness surface can still deviate significantly from a smooth flat target profile due to non-perpendicular surface processing leading to a sloped or wedge-shaped profile as illustrated in Figure 4.
Similar deviations to those illustrated in Figures 3 and 4 for flat surface can also occur when a curved surface profile is desired.
Such deviations from a target profile may be caused by stress introduced into the super-hard material during synthesis and/or during surface processing which can lead to bowing in a super-hard material Furthermore, macroscopic deviations from a smooth target profile may also result due to non-uniform processing.
The aforementioned issues are typically more problematic for super-hard materials when compared to less hard materials for a number of reasons as discussed below.
First, synthesis conditions for super-hard materials are often extreme, e.g. very high pressures and/or temperatures, leading to stress in the synthesized super-hard material which can cause bowing.
Secondly, the extreme hardness of super-hard materials typically requires a large amount of energy to be imparted to process a surface of the material and this generates heat leading to the generation of thermal stress during processing which can again lead to bowing.
Thirdly, due to the extreme hardness of super-hard materials, abrasive particles can be broken down into smaller particles during processing of a super-hard material which can result in differential processing of, for example, central and outer regions of a wafer of super-hard material.
Fourthly, the extreme hardness of super-hard materials typically requires a large force do be applied to the super-hard material during processing and if this force isn't uniformly applied across the surface of the super-hard material during process a sloped or wedge-shaped profile can result.
Fifthly, the extreme hardness of super-hard materials typically requires a large force do be applied to the super-hard material during processing and this can lead to development of non-uniformities in the surface of the processing wheel over time, e.g. deviations from a flat processing surface, which can be result in corresponding non-uniformities in the surface of the surface of the super-hard materials being processed.
In addition to the above, even if a smooth, flat surface can be achieved by a particular surface processing method, or a combination of surface processing methods, problems may still exist in terms of crystal defects/damage being imparted into the crystal surface and sub-surface.
Figure 5 illustrates a super-hard material having a smooth and flat surface but where micro-cracks have been formed in a surface region due to forces imparted during the processing of the surface to a high degree of smoothness and flatness, This is a particular problem for super-hard materials due to the high hardness and low toughness of such materials, Several different methods are available for measuring surface and sub-surface crystal damage. For example, one technique involves applying a revealing plasma etch to the processed surface which preferentially etches cracked or damaged regions to form etch pits which can then be counted to evaluate the density of defects at the processed surface.
In light of the above, it is evident that while it is desirable for many applications to form low roughness and highly flat or precisely curved surfaces without imparting defects/damage into the crystal structure there are many problems associated with forming such surfaces in super-hard materials.
It is an aim of embodiments of the present invention to provide a method of processing super-hard materials to form low roughness and highly flat or precisely curved surfaces without imparting defects/damage into the crystal structure.
Summary of Invention
Embodiments of the present invention are directed to surface processing of a super-hard material by lapping and polishing. As described in the background section, conventionally a three-body lapping process, in which abrasive grit supported in a fluid is introduced between a processing wheel and a super-hard material, is used to remove material from the surface of an as-grown super-hard material in order to increase surface flatness, decrease surface roughness, remove surface defects, and/or attain a target thickness for the super-hard material. Subsequently, if a fine surface finish is required, the super-hard material is polished and this may be performed using a two-body surface processing technique in which abrasive material is fixed in a polishing wheel such as via resin bonding.
The present inventors have found that while a freshly prepared polishing wheel can process a surface of a super-hard material to form a finely polished, low roughness, and highly flat or precisely curved surface, analysis of the surface and sub-surface crystal microstructure reveals that significant surface and sub-surface crystal damage is introduced into the crystal structure, The present inventors have surprisingly found that if a blunted polishing wheel is used to process a super-hard material, i.e. a polishing wheel which has been subjected to significant mechanical wear prior to use, then the surface and sub-surface crystal damage introduced into the crystal structure during polishing is significantly reduced while still achieving a low roughness and highly flat or precisely curved surface. This is particularly useful for certain optical, electronic, and quantum sensing and processing applications which are adversely affected by surface and sub-surface crystal damage caused by polishing.
Furthermore, a reduction in such crystal damage can lead to a surface with better structural integrity which may be useftil for mechanical applications of super-hard materials.
In light of the above, according to a first aspect of the present invention there is provided a method of processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2, the method comprising: (a) forming a processing surface by adhering abrasive particles to a caner substrate; (b) preparing the processing surface by removing, at least in part, sharp edges from the abrasive particles extending outwards from the processing surface to fonn a Nunted processing surface; (c) disposing a surface of the super-hard material in contact with the blunted processing surface; and (d) polishing the surface of the super-hard material with the blunted processing surface.
According to a second aspect of the present invention there is provided a super-hard material product fabricated using the method as defined above.
Brief Description of the Drawings
For a better understanding of the present invention and to show how the same may be carried into effect, embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which: Figure t shows a smooth curved surface; Figure 2 shows a flat rough surface; Figure 3 shows a schematic illustration of a wafer of super-hard material which has bowed from a targeted flat configuration due to stress induced during synthesis and/or surface processing and/or due to non-uniform processing; Figure 4 shows a schematic illustration of a wafer of super-hard material which has a wedge shaped profile deviating from a targeted flat configuration due to non-uniform processing; Figure 5 shows a schematic illustration of a wafer of super-hard material which has a smooth flat surface profile which comprises surface damage in the form of microcracks introduced during surface processing; and Figure 6 shows a flow diagram illustrating a surface processing technique for processing a super-hard material according to an embodiment of the present invention.
Detailed Description
Figures ito S have already been discussed in the background section of this specification and serve to illustrate some different types of surfaces which can be generated during synthesis and processing of a super-hard material, Particular problems in processing super-hard materials have also been discussed in the background section and the desire to develop improved surface processing methodology for super-hard materials in order to achieve low roughness and highly flat or precisely curved surfaces without imparting defects/damage into the crystal structure.
Embodiments of the present invention have been developed to address the aforementioned problems and are particularly directed to two-body fine surface polishing which may be applied after a lapping process. As described in the summary of invention section and illustrated in Figure 6, a first aspect of the present invention provides a method of processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2 and which is required to have minimal surface and sub-surface damage. This will usually be a high value super-hard material part for use in certain optical, electronic, and quantum sensing and processing applications which are adversely affected by surface and sub-surface crystal damage caused by polishing, Alternatively, the super-hard material part may be required for certain extreme mechanical applications which require a surface with extreme precision and/or structural integrity, In step (a), a processing surface 2 is formed by adhering abrasive particles 4 to a carrier substrate 6, In the illustrated embodiment this is achieved by embedding the abrasive particles 4 in a layer of resin 8 disposed on the carrier substrate 6 to form a resin bond polishing wheel.
In step (b), the processing surface 2 is preparing by removing, at least in part, sharp edges from the abrasive particles 4 extending outwards from the processing surface 2 to form a
S
blunted processing surface 10. In the illustrated embodiment this is achieved by subjecting the processing surface 2 to mechanical wear, e.g. by polishing another super-hard material part 12. The super-hard material part 12 used in this surface preparation step should be one which is relatively low value. Such a super-hard material part 12 used in this surface preparation step may be discarded after use or it may form another product which does not require an extremely low crystal damage surface finish when compared to the processed super-hard material product of the present invention.
In step (c), a surface of a super-hard material 14 which is required to have a low crystal damage surface finish is disposed in contact with the blunted processing surface 10 as prepared in step (b).
Finally, in step (d), the surface of the super-hard material 14 is polished with the blunted processing surface 10 to form a low roughness and highly flat (or alternatively precisely curved as required) surface which has very low surface and sub-surface crystal damage.
According to certain embodiments, in step (a) the concentration of abrasive particles distributed over the carrier substrate (particles/cm2) and/or the distributed of abrasive particles through a layer of resin (particles/cm3) can be controlled to obtain a desired surface finish for the super-hard material product 14, Furthermore, an average particle size D50 of the abrasive particles and/or a D90 abrasive particle size may be controlled to obtain a desired surface finish. That is, by controlling the abrasive particle loadings and particle sizes, in combination with the blunting process as described herein, it is possible to achieve a desired surface finish for the super-hard material product with a very low roughness and low crystal damage.
After step (a), the processing surface 2 is relatively rough whereas after step (b) the blunted processing surface is significantly smoother as a result of the blunting process. Furthermore, in addition to controlling surface parameters of the processing surface, in steps (c) and (d) the force or pressure with which the super-hard material is pressed against the blunted processing surface, the speed with which the blunted processing surface is rotated, and the time period over which the super-hard material is polished with the blunted processing surface can be controlled to obtain a desired surface finish in terms of roughness and crystal damage.
After step (d), the processed super-hard material product may have a surface roughness Ra of no more than 20 nm, 15 nm, 10 nm, 5 nm, 3 nm, or 1 nm and has a low level of surface and sub-surface crystal damage, e.g. a low level of micro-cracks.
As previously indicated, the present processing methodology is particularly useful for high value super-hard material parts for use in certain optical, electronic, and quantum sensing and processing applications which are adversely affected by surface and sub-surface crystal damage caused by polishing. For example, the processing methodology is particularly suited for single crystal or polycrvstalline CVD diamond materials and particularly optical, electronic, and quantum grades of such materials available from Element Six Limited.
For example, the super-hard material may be a synthetic diamond material having one or more of the following characteristics: an absorption coefficient measured at room temperature of i 0.5 cm'1, «= 0.4 cm'1, «= 0,3 cm", 0.2 cm", 0.t cm", 0.07 cm" or 0.05 cm" at a wavelength of 10.6 m; a dielectric loss coefficient tan 6 measured at room temperature at 145 GHz of 2 x l0, S x l0', 10', S x 10.6, or 10; an average microfeature density no greater than S mm'2, 3 mm'2, I mm'2, 0.5 mm'2, or 0.1 mm'2; a microfeature distribution such that there are no more than 5, 4, 3, 2, or I microfeatures within any 3 mm2 area; an integrated absorbance per unit thickness of no more than 0.20 cm2, 0.15 cm2, 0.10 cm'2, or 0.05 cm'2, when measured with a corrected linear background in a range 2760 cm" to 3030 cm'; a thermal conductivity of no less than 1800 Wm' K', 1900 Wm'1 K', 2000 Wm" K', 2100 Wm"K", or 2200 Wm"K"; a silicon concentration as measured by secondary ion mass spectrometry of no more 17 3 16 -3 16 -3 15 -3 15 -3 thanlO cm,SxtO cm,10 cm,5x10 cm,orlO cm; a nitrogen concentration as measured by secondary ion mass spectrometry of no more 18 -3 17 -3 16 -3-16 -3 15 -3 15 -3 thanlO cm,SxlO cm,5x10 cm,10 cm,5x10 cm,orlO cm;and nitrogen vacancy defects (NV') having a decoherence time T2 at room temperature of at least 100 is, 300 us, 500 us, I ms, 2 ms, S ms, 10 ms, SUms, or 100 ms.
In general, the super-hard material which is used to blunt the processing surface (prior to polishing the super-hard material product) will be a lower value super-hard material which does not meet one or more of the aforementioned requirements. For example, in step (b) of the present process the processing surface may be prepared by polishing a lower value super-hard material product (e.g. a lower grade synthetic diamond material) which does not require a ow crystal damage surface finish and which may have one or more of the following characteristics: an absorption coefficient measured at room temperature of? 0.5 cm'1, ? 0,4 cm'1, ? 0,3 cm", ? 0,2 cm", ? 0.1 cm", ? 0.07 cm" or? 0.05 cm" at a wavelength of 10.6 um; a dielectric loss coefficient tan ö measured at room temperature at 145 GHz of? 2 x 10',? io, ? 5 x i0',? 10',? 5 x 106, or? 1o; an average microfeature density no less than 5 mm'2, 3 mm'2, t mm'2, 0.5 mm'2, or 0. mm'2;
a microfeature distribution such that there are no less than 5, 4, 3, 2, or 1 microfeatures within any 3 mm2 area; an integrated absorbance per unit thickness of no less than 0.20 cm'2, 0.15 cm'2, 0.10 cm'2, or 0.05 cm'2, when measured with a corrected linear background in a range 2760 cm' to 3030 cm"; a thermal conductivity of no more than 1800 Wm"K", 1900 Wm"K4, 2000 Wm"K", 2100 Wm"K", or 2200 Wm"K"; a silicon concentration as measured by secondary ion mass spectrometry of no less 17 3 16 -3 16 -3 15 -3 15 3 thanlo cm,5x10 cm,10 cm,SxIO cm,orIO cm; a nitrogen concentration as measured by secondary ion mass spectrometry of no less than 10's cm'3, cm", 5 x cm'3, j( cm'3, 5 x 10 cm'3, or cm'3; and nitrogen vacancy defects (NV') having a decoherence time T2 at room temperature of at most tOO us, 300 jis, 500 u, 1 ms, 2 ms, 5 ms, tO ms, SUms, or tOO ms, While this invention has been particularly shown and described with reference to embodiments, it 11 be understood to those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as defined by the appending claims.
Claims (10)
- Claims 1. A method of processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2, the method comprising: (a) forming a processing surface by adhering abrasive particles to a carrier substrate; (b) preparing the processing surface by removing, at least in part, sharp edges from the abrasive particles extending outwards from the processing surface to form a blunted processing surface; (c) disposing a surface of the super-hard material in contact with the blunted processing surface; and (d) polishing the surface of the super-hard material with the blunted processing surface to form a processed super-hard material product.
- 2. A method according to claim 1, wherein, in step (a), the abrasive particles are adhered to the carrier substrate by embedding the abrasive particles in a layer of resin disposed on the carrier substrate.
- 3, A method according to claim I or 2, wherein, in step (b), the processing surface is prepared by subjecting the processing surface to mechanical wear.
- 4. A method according to claim 3, wherein the mechanical wear is achieved by polishing another super-hard material which does not require a low crystal damage surface finish when compared to the processed super-hard material product formed in step (d).
- 5. A method according to any preceding claim, wherein, after step (b), the blunted processing surface has a lower surface roughness than before step (b).
- 6. A method according to any preceding claim, wherein, after step (d), the processed super-hard material product has a surface roughness Ra of no more than 20 nm, 15 nm, 10 nm, 5 nm, 3 nm, or 1 nm.
- 7. A method according to any preceding claim, wherein the super-hard material is single crystal CVD diamond or polycrystalline CVD diamond.
- 8. A method according to any preceding claim, wherein the super-hard material is a synthetic diamond material having one or more of the following characteristics: an absorption coefficient measured at room temperature of i 0.5 cm", 0.4 cm", 0.3 cm", 0.2 cm", 0.1 cm", 0.07 cm" or <0.05 cm" at a wavelength of 10.6 m; a dielectric loss coefficient tan 6 measured at room temperature at 145 GH.z of 2 x <l0, <5 x l0, < 10's, < x 10.6, or< an average microfeature density no greater than 5 mm'2, 3 mm'2, 1 mm'2, 0.5 mm'2, or 0.1 mm'2; a microfeature distribution such that there are no more than 5, 4, 3, 2, or 1 microfeatures within any 3 mm2 area; an integrated absorbance per unit thickness of no more than 0,20 cm'2, 0.15 cm'2, 0.10 cm'2, or 0.05 cm'2, when measured with a corrected linear background in a range 2760 cm" to 3030 cm'; a thermal conductivity of no less than 1800 Wm'1K", 1900 Wm"K", 2000 Wm"K", 2100 Wm"K", or 2200 Wm"K"; a silicon concentration as measured by secondary ion mass spectrometry of no more 17 -3 16 -3 16 -3 15 -3 15 3 thanlO cm,SxlO cm,10 cm,SxlO cm,orlO cm; a nitrogen concentration as measured by secondary ion mass spectrometry of no more 18 -3 17 -3 16 -3-16 -3 15 -3 15 -3 thanlO cm,SxlO cm,SxlO cm,10 cm,SxlO cm,orlO cm;and nitrogen vacancy defects (NV') having a decoherence time T2 at room temperature of at least 100,ts, 300 us, 500 us, I ms, 2 ms, S ms, 10 ms, SUms, or 100 ms.
- 9. A method according to claims 1, 3, and 4, wherein the super-hard material used in step (b) to prepare the processing surface is a synthetic diamond material having one or more of the following characteristics: an absorption coefficient measured at room temperature of? 0.5 cm" at a wavelength of 10.6 Rm; a dielectric loss coefficient tan S measured at room temperature at 145 Gl-lz of? 2 x iO'4; an average microfeature density no less than 5 mm'2; a microfeature distribution such that there are no less than S microfeatures within any 3 mm2 area; an integrated absorbance per unit thickness of no less than 0,20 cm'2 when measured with a corrected linear background in a range 2760 cm" to 3030 cm"; a thermal conductivity of no more than 1800 Wm'1K"; a silicon concentration as measured by secondary ion mass spectrometry of no less 16 -than 10 cm-; a nitrogen concentration as measured by secondary ion mass spectrometry of no less than 1016 cm1; and nitrogen vacancy defects (NV') having a decoherence time T2 at room temperature of at most 100 us.
- 1 0, A super-hard material product fabricated using a method according to any preceding claim,
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1410848.4A GB2528638A (en) | 2014-06-18 | 2014-06-18 | Post-synthesis processing of diamond and related super-hard materials |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1410848.4A GB2528638A (en) | 2014-06-18 | 2014-06-18 | Post-synthesis processing of diamond and related super-hard materials |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201410848D0 GB201410848D0 (en) | 2014-07-30 |
| GB2528638A true GB2528638A (en) | 2016-02-03 |
Family
ID=51266776
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1410848.4A Withdrawn GB2528638A (en) | 2014-06-18 | 2014-06-18 | Post-synthesis processing of diamond and related super-hard materials |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2528638A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111638305B (en) * | 2020-06-08 | 2023-09-22 | 郑州磨料磨具磨削研究所有限公司 | Method for determining optimal processing direction of monocrystalline material |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0796461A (en) * | 1993-09-29 | 1995-04-11 | Komatsu Ltd | Method for adjusting grinding wheel with super abrasive grain, and truer for super abrasive grain and electric discharge |
| JPH10235553A (en) * | 1997-02-24 | 1998-09-08 | Osaka Diamond Ind Co Ltd | Diamond lapping surface plate and manufacture therefor |
| US20020173228A1 (en) * | 2001-04-23 | 2002-11-21 | Munehisa Gunjima | Grinder and method of and apparatus for non-contact conditioning of tool |
| JP2009056517A (en) * | 2007-08-30 | 2009-03-19 | Yamagata Prefecture | Method and tool for truing diamond wheel |
-
2014
- 2014-06-18 GB GB1410848.4A patent/GB2528638A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0796461A (en) * | 1993-09-29 | 1995-04-11 | Komatsu Ltd | Method for adjusting grinding wheel with super abrasive grain, and truer for super abrasive grain and electric discharge |
| JPH10235553A (en) * | 1997-02-24 | 1998-09-08 | Osaka Diamond Ind Co Ltd | Diamond lapping surface plate and manufacture therefor |
| US20020173228A1 (en) * | 2001-04-23 | 2002-11-21 | Munehisa Gunjima | Grinder and method of and apparatus for non-contact conditioning of tool |
| JP2009056517A (en) * | 2007-08-30 | 2009-03-19 | Yamagata Prefecture | Method and tool for truing diamond wheel |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201410848D0 (en) | 2014-07-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Schuelke et al. | Diamond polishing | |
| Zhou et al. | A study on the diamond grinding of ultra-thin silicon wafers | |
| Liu et al. | Grinding wheels for manufacturing of silicon wafers: a literature review | |
| Zhong et al. | Grinding of alumina/aluminum composites | |
| Hird et al. | Diamond polishing | |
| TWI548503B (en) | Scribing wheel, its manufacturing method and crossed method | |
| Gu et al. | Effect of cutting tool geometries on the ductile-brittle transition of monocrystalline sapphire | |
| KR20160112000A (en) | Substrate including a diamond layer and a composite layer of diamond and silicon carbide, and, optionally, silicon | |
| TW200837823A (en) | CMP pad conditioners and associated methods | |
| WO2009158507A2 (en) | Chemical mechanical planarization pad conditioner and method of forming | |
| Mao et al. | Wear mechanism of single cBN-WC-10Co fiber cutter in machining of Ti-6Al-4V alloy | |
| Kovalchenko et al. | Suppressing scratch-induced brittle fracture in silicon by geometric design modification of the abrasive grits | |
| Almeida et al. | Nanocrystalline CVD diamond coatings for drilling of WC-Co parts | |
| Lin et al. | Mechanism of material removal by fixed abrasive lapping of fused quartz glass | |
| Xu et al. | An efficient titanium-containing corundum wheel for grinding CVD diamond films | |
| US10214835B2 (en) | Post-synthesis processing of diamond and related super-hard materials | |
| CN108728816A (en) | Wire-drawing die and preparation method thereof with a variety of coatings | |
| Luo et al. | Studies on cut-off grinding of BK7 optical glass using thin diamond wheels | |
| GB2528638A (en) | Post-synthesis processing of diamond and related super-hard materials | |
| CN103367242A (en) | Combined trimmer and manufacturing method thereof and chemical mechanical polishing method | |
| EP2634295A1 (en) | Method for producing gemstones from silicon carbide | |
| CN206550883U (en) | A kind of CVD polycrystalline diamond abrasive sticks of nucleation face mirror finish | |
| KR101233239B1 (en) | Recycling method of CMP pad conditioner having end of life and recycled CMP pad conditioner treated thereby | |
| CN105473283A (en) | Form dressing roller | |
| WO2015096986A1 (en) | Post-synthesis processing of diamond and related super-hard materials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |