Substrate, substrate splicing method and preparation method of single crystal diamond
阅读说明：本技术 衬底及衬底的拼接方法和单晶金刚石的制备方法 (Substrate, substrate splicing method and preparation method of single crystal diamond ) 是由 何斌 曹海涛 韩培刚 黄江涛 陈文婷 张宗雁 于 2021-07-05 设计创作，主要内容包括：本发明涉及单晶金刚石技术领域,具体提供一种衬底及衬底的拼接方法和单晶金刚石的制备方法。所述衬底的拼接方法包括以下步骤：提供单晶金刚石籽晶,单晶金刚石籽晶具有底表面和与底表面相背的顶表面；单晶金刚石籽晶具有自底表面至顶表面的第一高度；沿第一高度的等分线切割单晶金刚石籽晶,使单晶金刚石籽晶被切割成具有相同第二高度的多块籽晶；将多块籽晶沿垂直于第二高度的方向进行拼接,且使相互拼接的籽晶之间的晶体取向相同,由此获得衬底。本发明可获得晶体取向相同的衬底,从而有助于节省单晶金刚石的加工工序,提高单晶金刚石的生长效率以及获得大尺寸、高质量的单晶金刚石。(The invention relates to the technical field of single crystal diamond, and particularly provides a substrate, a substrate splicing method and a single crystal diamond preparation method. The substrate splicing method comprises the following steps: providing a single crystal diamond seed having a bottom surface and a top surface opposite the bottom surface; the single crystal diamond seed has a first height from the bottom surface to the top surface; cutting the single crystal diamond seed crystal along a bisector of the first height such that the single crystal diamond seed crystal is cut into a plurality of seed crystals having the same second height; and splicing a plurality of seed crystals in a direction perpendicular to the second height, and making the crystal orientations of the seed crystals spliced with each other the same, thereby obtaining the substrate. The invention can obtain the substrate with the same crystal orientation, thereby being beneficial to saving the processing procedure of the single crystal diamond, improving the growth efficiency of the single crystal diamond and obtaining the large-size and high-quality single crystal diamond.)
1. A method of splicing substrates, comprising the steps of:
providing a single crystal diamond seed having a bottom surface and a top surface opposite the bottom surface; the single crystal diamond seed has a first height from the bottom surface to the top surface;
cutting the single crystal diamond seed along a bisector of the first height such that the single crystal diamond seed is cut into a plurality of seeds having a same second height;
and splicing a plurality of the seed crystals in a direction perpendicular to the second height, and making the crystal orientations of the seed crystals spliced with each other the same, thereby obtaining a substrate.
2. The method of splicing substrates of claim 1, wherein the single crystal diamond seed further comprises a circumferential side surface extending from an edge of the bottom surface toward the top surface and connected to an edge of the top surface;
before the cutting, the step of reducing the roughness of the circumferential side surface is further included, and the cutting is carried out along a bisector of the first height;
or, before the cutting, the step of reducing the roughness of the circumferential side surface is further included, and the cutting is performed along the trisection line of the first height;
alternatively, the method further comprises a step of reducing the roughness of the circumferential side surface before the cutting, and the cutting is performed along a bisector of the first height.
3. The method for splicing substrates according to claim 2, wherein two splicing surfaces of two seed crystals spliced with each other are parallel to each other, and the roughness of both the splicing surfaces is not more than 0.8 nm.
4. The method for splicing substrates according to claim 2, wherein a gap between two seed crystals spliced to each other is less than 5.0 nm.
5. The method for splicing substrates according to any one of claims 1 to 4, wherein a plurality of said seed crystals obtained have cut faces, and further comprising, before said splicing, a step of reducing roughness of said cut faces.
6. The method for splicing substrates according to any one of claims 1 to 4, further comprising the step of subjecting the top surface and the cut surfaces of a plurality of the seed crystals to a finish grinding process so that the top surface, the cut surfaces are parallel to the bottom surface.
7. A substrate is characterized in that the substrate is formed by splicing a plurality of seed crystals, and the crystal orientations of the plurality of seed crystals spliced with each other are the same;
the substrates are spliced by the splicing method of any one of claims 1 to 6.
8. The substrate according to claim 7, wherein a gap between two adjacent seed crystals spliced to each other in the substrate is less than 5.0 nm.
9. A method for producing a single crystal diamond, comprising the steps of:
providing a substrate according to any one of claims 7 to 8;
the substrate has a top surface on which a layer of single crystal diamond is grown to obtain single crystal diamond.
10. A method of producing single crystal diamond according to claim 9, further comprising the step of separating the substrate from the single crystal diamond layer.
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of single crystal diamond, in particular to a substrate, a substrate splicing method and a single crystal diamond preparation method.
[ background of the invention ]
At present, natural diamond or artificially synthesized single-crystal diamond diaphragms are usually adopted as seed crystals to grow on the original sizes of the natural diamond or the artificially synthesized single-crystal diamond diaphragms, but because the large-size natural diamond is very rare and expensive, the artificially synthesized single-crystal diamond is limited by the sizes of the seed crystals, the top surface area of the crystals gradually becomes smaller along with the growth of a diamond growth layer, and the obtaining of the large-size single-crystal diamond diaphragms is limited, so that the sizes of the diamonds obtained by the existing method are limited.
In order to obtain a large-sized single crystal diamond, the prior art splices a plurality of small-sized single crystal diamond seed crystals together to obtain a substrate spliced by the plurality of small-sized single crystal diamond seed crystals, and then performs homoepitaxial growth on the surface of the substrate to obtain the large-sized single crystal diamond. However, this splicing growth method has at least the following drawbacks:
(1) the seed crystal has high selection difficulty, complex splicing process and poor splicing effect. The method comprises the following specific steps: the growth method requires that the size, thickness and crystal orientation of two spliced seed crystals are completely consistent to generate the large-size single crystal diamond with good quality. However, whether a naturally occurring natural single crystal diamond seed or an artificially synthesized single crystal diamond seed, after processing into platelets of {100} crystal orientation, the crystal orientations of the different platelets may not be perfectly identical. In order to obtain a good splicing effect, two different seed crystals need to be spliced according to the crystal orientation, so that the crystal orientations of a plurality of seed crystals need to be accurately analyzed and calibrated, then two proper seed crystals are selected, and meanwhile, the angle of the splicing surface of the two selected seed crystals needs to be measured and polished and adjusted, so that the complexity of the large-size single crystal diamond growth process is greatly increased.
(2) And the growth efficiency of the single crystal diamond is low, and the obtained single crystal diamond has more defects. The method comprises the following specific steps: the seed crystal selection process is complex, so that the processing efficiency of the large-size single crystal diamond is low; in the spliced substrate, as long as the crystal orientations of a plurality of seed crystals are slightly different, a subboundary and even a macroscopic gap are easily left at the spliced part of the growth layer when the single crystal diamond layer grows, so that the quality of the large-size single crystal diamond is influenced.
Therefore, there is a need to provide a new technical solution to solve the above technical problems of the existing large-sized diamond processing.
[ summary of the invention ]
The invention aims to provide a substrate and a substrate splicing method, which are used for solving the problems that the existing seed crystal is difficult to select and use, the splicing process is complex, the splicing effect is poor, and large-size single crystal diamond is not easy to obtain.
In order to realize the technical goal, the following technical scheme is adopted:
a method of splicing substrates, comprising the steps of:
providing a single crystal diamond seed having a bottom surface and a top surface opposite the bottom surface; the single crystal diamond seed has a first height from the bottom surface to the top surface;
cutting the single crystal diamond seed along a bisector of the first height such that the single crystal diamond seed is cut into a plurality of seeds having a same second height;
and splicing a plurality of the seed crystals in a direction perpendicular to the second height, and making the crystal orientations of the seed crystals spliced with each other the same, thereby obtaining a substrate.
The second purpose of the invention is to provide a substrate, which is formed by splicing a plurality of seed crystals, and the crystal orientations of the plurality of seed crystals spliced with each other are the same;
the substrate is obtained by splicing by the splicing method.
The invention also aims to provide a preparation method of the single crystal diamond, which comprises the following steps:
providing a substrate as described above;
and growing a layer of single crystal diamond on one surface of the substrate to obtain single crystal diamond.
Further, a step of cutting the substrate and the single crystal diamond layer so that the substrate is separated from the single crystal diamond layer is further included.
The invention has the beneficial effects that:
compared with the prior art, the substrate splicing method and the single crystal diamond preparation method provided by the invention have the advantages that one single crystal diamond seed crystal is cut into a plurality of seed crystals with the same height, then the plurality of seed crystals are spliced, and the crystal orientations among the plurality of mutually spliced seed crystals are ensured to be the same, so that the substrate with the same crystal orientation can be obtained, the area of the substrate for growing the single crystal diamond is multiplied by more than the area of the growth surface of one single crystal diamond seed crystal, the substrate obtained by the method can ensure that the crystal orientations of the plurality of seed crystals are the same, the accurate analysis, calibration and selection of the crystal orientations of the spliced seed crystals are not needed, the processing procedure of the single crystal diamond is greatly simplified, and the growth efficiency of the single crystal diamond is improved; more importantly, because the plurality of seed crystals are derived from the same single crystal diamond seed crystal, the crystal orientations of the plurality of seed crystals spliced with each other are completely consistent, and the obtained substrate is beneficial to growth and obtaining of large-size and high-quality single crystal diamond.
[ description of the drawings ]
Fig. 1 is a simplified flow chart of a method for splicing substrates according to an embodiment of the present invention;
FIG. 2 is a simplified flow diagram of a method of producing single crystal diamond according to one embodiment of the present invention;
fig. 3 is an SEM image of a single crystal diamond at a substrate splicing interface obtained by the method for producing a single crystal diamond according to the first embodiment of the present invention;
FIG. 4 is an AFM image of a single crystal diamond at a substrate splicing interface obtained by the method for preparing a single crystal diamond according to the first embodiment of the present invention;
FIG. 5 is a simplified flowchart of a method for splicing substrates according to a second embodiment of the present invention;
fig. 6 is a simplified flow chart of a method for splicing substrates according to a third embodiment of the present invention;
FIG. 7 is a simplified flowchart of a method for splicing substrates according to a fourth embodiment of the present invention;
fig. 8 is a simplified flowchart of a method for splicing substrates according to a fifth embodiment of the present invention;
fig. 9 is a simplified flowchart of a method for splicing substrates according to a sixth embodiment of the present invention;
fig. 10 is a simplified flow chart of a method for splicing substrates according to a seventh embodiment of the present invention;
fig. 11 is a schematic perspective view of a substrate according to a seventh embodiment of the present invention.
[ detailed description ] embodiments
The invention is further described with reference to the following figures and embodiments. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
Example one
As shown in fig. 1 to 4, this embodiment provides a substrate 1000, a method of splicing the substrate 1000, and a method of producing a single crystal diamond 3000.
Referring to fig. 1, the method for splicing the substrates 1000 includes the following steps:
s10, providing a single crystal diamond seed 100.
The single crystal diamond seed crystal 100 has a bottom surface 1, a top surface 2, and a peripheral side surface 3, wherein the bottom surface 1 and the top surface 2 are oppositely disposed, and the peripheral side surface 3 extends from an edge of the bottom surface 1 toward the top surface 2 and is connected to an edge of the top surface 2; the single crystal diamond seed 100 has a first height H from the bottom surface 1 to the top surface 2.
In one embodiment, the circumferential side surface 3 includes a first circumferential surface 31, a second circumferential surface 32, a third circumferential surface 33, and a fourth circumferential surface 34, the first circumferential surface 31 and the third circumferential surface 33 are disposed oppositely, and the second circumferential surface 32 and the fourth circumferential surface 34 each extend from two opposite edges of the first circumferential surface 31 toward the third circumferential surface 33, respectively, and are connected to two opposite edges of the third circumferential surface 33, respectively. In some embodiments, the single crystal diamond seed 100 has dimensions of 1000 μm by 500 μm by 300 μm, with a length of 1000 μm, a width of 500 μm, and a height (i.e., first height H) of 300 μm.
S11, the top surface 2 of the single crystal diamond seed crystal 100 is ground so that the top surface 2 and the bottom surface 1 are parallel to each other and the roughness of the top surface 2 is reduced.
In some embodiments, the roughness of the finish-ground top surface 2 is not greater than 0.8 nm. In some embodiments, further comprising subjecting the bottom surface 1 to a finish grinding process, again such that the roughness of the bottom surface 1 is no greater than 0.8 nm.
S12, polishing the first circumferential surface 31 and the third circumferential surface 33 to reduce the roughness of the first circumferential surface 31 and the third circumferential surface 33. The roughness of the first circumferential surface 31 and the third circumferential surface 22 is reduced, which is beneficial to reducing the gap between the two mutually spliced surfaces of the substrate 1000 obtained by subsequent splicing.
In some embodiments, the roughness of the polished first circumferential surface 31 is not more than 0.8 nm. When the roughness of the first circumferential surface 31 is not more than 0.8nm, two seed crystals spliced with each other can be closely arranged together, and an ideal splicing effect is achieved.
In some embodiments, the roughness of the polished third circumferential surface 33 is not more than 0.8 nm. When the roughness of the third circumferential surface 33 is not more than 0.8nm, two seed crystals spliced with each other can be closely arranged together, and an ideal splicing effect is achieved.
In some embodiments, the polishing process comprises at least one of mechanical polishing, chemical polishing, and electrochemical polishing.
In some embodiments, the polishing process is not limited to the first circumferential surface 31 and the third circumferential surface 33, and may further include polishing at least one of the second circumferential surface 32 and the fourth circumferential surface 34.
S13, bisect first height H to obtain bisector 35, and bisector 35 in this embodiment is bisector 351.
Specifically, the first height H of the single crystal diamond seed crystal 100 may be equally divided on any face of the circumferential side surface 3, and the marking process may be performed on any face of the circumferential side surface 3. In one embodiment, the first height H is bisected on the second circumferential surface 32, and the bisector line 351 is marked to obtain the bisector line 351 and the mark 36 partially covering the bisector line 351, so as to facilitate accurate separation of the seed crystals during cutting and splicing.
S14, cutting the single crystal diamond seed crystal 100 along bisector line 351 such that the single crystal diamond seed crystal 100 is cut into the first seed crystal 200 and the second seed crystal 300. The first seed crystal 200 and the second seed crystal 300 both have a height, i.e., both have a second height H (H ═ 2H), and the first circumferential surface 31 is cut into a first side surface 311 and a second side surface 312, and the third circumferential surface 33 is cut into a ninth side surface 331 and a tenth side surface 332, wherein the first side surface 311 and the ninth side surface 331 are both located on the first seed crystal 200, and the second side surface 312 and the tenth side surface 332 are both located on the second seed crystal 300; meanwhile, the mark 36 is cut into a first mark 361 and a second mark 362, wherein the first mark 361 is located on the first seed crystal 200 and the second mark 362 is located on the second seed crystal 300.
In some embodiments, both the first seed crystal 200 and the second seed crystal 300 obtained by cutting have cut faces, that is, the first seed crystal 200 has a first cut surface 201, the second seed crystal 300 has a second cut surface 301, since the first cut surface 201 and the second cut surface 301 obtained by cutting are not necessarily flat, a step of performing a finish grinding or polishing process on the first cut surface 201 and the second cut surface 301 may be further included, so that the roughness of the first cutting surface 201 and the roughness of the second cutting surface 301 are not more than 0.8nm and are parallel to the bottom surface 1, the height of the first seed crystal 200 and the height of the second seed crystal 300 are the same after the fine grinding or polishing treatment, thereby being beneficial to reducing the surface defects of the first seed crystal 200 and the second seed crystal 300, improving the mutual splicing effect of the first seed crystal 200 and the second seed crystal 300 and simultaneously being beneficial to the epitaxial growth on the surface of the spliced substrate 1000.
S15, the first seed crystal 200 and the second seed crystal 300 are spliced in a direction perpendicular to the second height h such that the crystal orientation of the first seed crystal 200 and the crystal orientation of the second seed crystal 300 spliced to each other are the same, thereby obtaining the substrate 1000. The spliced substrate 1000 has a size of 2000 μm × 500 μm × 150 μm, where 2000 μm denotes a length; 500 μm represents the width; 150 μm represents the height, i.e., the second height h, i.e., the height of the resulting stitched substrate 1000 is one-half the height of the single crystal diamond seed 100.
Specifically, since the first seed crystal 200 and the second seed crystal 300 are obtained by cutting the single-crystal diamond seed crystal 100 on the second circumferential surface 32 along the bisector 351 of the first height H, the first side surface 311 on the first seed crystal 200 and the second side surface 312 on the second seed crystal 300 both face in the same direction, the ninth side surface 331 on the first seed crystal 200 and the tenth side surface 332 on the second seed crystal 300 both face in the same direction, the first side surface 311 and the ninth side surface 331 are oppositely arranged in the first seed crystal 200, the second side surface 312 and the tenth side surface 332 are oppositely arranged in the second seed crystal 300, and the first side surface 311 and the tenth side surface 332 are oppositely attached, thereby obtaining the substrate 1000. The resulting substrate 1000 has a bottom surface and a top surface, wherein the bottom surface is formed by the bottom surface 1 of the single crystal diamond seed 100 (in this case, the bottom surface of the first seed 200) and the second cut surface 301; the top surface is formed by the top surface 2 of the single crystal diamond seed crystal 100 (in this case, the top surface of the second seed crystal 300) and the first cut surface 201; the height from the bottom surface to the top surface of the substrate 1000 is the second height H, and the first height H of the single crystal diamond seed 100 is twice the height of the substrate 1000. In some embodiments, the substrate 1000 may also be obtained by attaching the second side 312 of the first seed crystal 200 and the ninth side 331 of the second seed crystal 300 in a facing manner.
In some embodiments, the two splicing surfaces of the first seed crystal 200 and the second seed crystal 300 spliced with each other are parallel to each other and perpendicular to the top surface and/or the bottom surface, thereby facilitating an improvement in splicing effect.
In some embodiments, the substrate 1000 obtained in steps S10 to S15 has a gap of less than 5.0nm at a portion where the first seed crystal 200 and the second seed crystal 300 are bonded to each other, thereby facilitating epitaxial growth of large-sized single crystal diamond on the top surface of the substrate 1000 or the bottom surface of the substrate 1000 and reducing defects of the large-sized single crystal diamond at the bonded portion.
This embodiment further provides a method for producing the single crystal diamond 3000 on the basis of obtaining the substrate 1000.
Referring to fig. 2, a method of manufacturing a single crystal diamond 3000 includes the steps of:
a single crystal diamond layer 2000 is grown on the top surface of the substrate 1000 obtained as described above, thereby obtaining a single crystal diamond 3000.
The method specifically comprises the following steps:
s16, performing homoepitaxial growth on the top surface of the substrate 1000 by using microwave plasma chemical vapor deposition, so that a layer of single crystal diamond 2000 is deposited on the top surface of the substrate 1000.
The specific process flow comprises the following steps: placing the substrate 1000 obtained in S15 into a vacuum chamber until the background vacuum degree reaches 10- 4After Pa, the molecular pump is closed; introducing H of 300sccm2Adjusting the working air pressure and the microwave power, and introducing 30sccm CH after the working air pressure is 20kPa, the microwave power reaches 3000W and the temperature of the sample is 850 DEG C4I.e. starting to grow the layer 2000 of single crystal diamond by controlling the growth time of the diamondAnd the growth rate controls the growth thickness of the single crystal diamond layer 2000.
In some embodiments, the top surface of the substrate 1000 obtained in step S15 may be cleaned before the microwave plasma cvd is performed, so as to ensure that the top surface of the substrate 1000 is clean and dry, which is beneficial to improve the growth quality of the single crystal diamond layer 2000.
S17, separating the substrate 1000 from the single crystal diamond layer 2000 by laser cutting, to obtain a large-sized single crystal diamond 3000.
The size of the obtained single crystal diamond 3000 was 2000 μm × 500 μm × X μm, where 2000 μm represents a length, 500 μm represents a width, and X μm represents a height, which can be determined according to the time of epitaxial growth. From this it can be seen that the length of the resulting single crystal diamond 3000 is doubled over the length of the single crystal diamond seed 100.
The characterization of the micro-morphology of the single crystal diamond 3000 obtained in this embodiment includes Scanning Electron Microscope (SEM) characterization and Atomic Force Microscope (AFM) characterization, wherein the SEM characterization results are shown in fig. 3, and MN indicates the morphology of the mutual splicing portion of the first seed crystal 200 and the second seed crystal 300; the results of the AFM characterization are shown in fig. 4.
As can be seen from fig. 3, the length of the single crystal diamond 3000 grown on the top surface of the substrate 1000 is indeed double the length of the single crystal diamond seed 100. More importantly, in the single crystal diamond 3000, the crystal orientation at MN, i.e., the surface of the portion where the first and second seed crystals 200 and 300 are spliced with each other, is the same as the crystal orientation at the first cutting plane 201 of the first seed crystal 200 and the top surface of the second seed crystal 300 (originally, the top surface 2 of the single crystal diamond seed crystal 100), while the crystal orientation of the single crystal diamond 3000 is also the same as the crystal orientations of the first and second seed crystals 200 and 300, without significant transition therebetween, and the MN presents a Mosaic (Mosaic) splicing interface microscopic morphology with nearly perfect transition.
As can be seen from fig. 4, the obtained single crystal diamond 3000 is tightly connected at the joint of the substrate 1000, and there is no obvious crack defect or sub-crystal interface at the interface, thereby effectively avoiding the problems of crack defect at the joint caused by lattice mismatch when the different single crystal diamond seed crystals 100 are jointed.
Example two
Referring to fig. 1, fig. 2 and fig. 5, the difference between the present embodiment and the first embodiment is that in the first embodiment, at least the first circumferential surface 31 and the third circumferential surface 33 are polished, and the second circumferential surface 32 is marked, and during the splicing, the substrate 1000 is obtained by attaching the first side surface 311 of the first seed crystal 200 and the tenth side surface 332 of the second seed crystal 300 in an opposite manner, or the substrate 1000 is obtained by attaching the second side surface 312 of the first seed crystal 200 and the ninth side surface 331 of the second seed crystal 300 in an opposite manner; in this embodiment, at least the second circumferential surface 32 and the fourth circumferential surface 34 are polished while the marking process is performed on the first circumferential surface 31, the second circumferential surface 32 is cut into the fifth side surface 321 and the sixth side surface 322, the fourth circumferential surface 34 is cut into the thirteenth side surface 341 and the fourteenth side surface 342, the fifth side surface 321 and the thirteenth side surface 341 are located on the first seed crystal 200, and the sixth side surface 322 and the fourteenth side surface 342 are located on the second seed crystal 300, and then the first seed crystal 200 and the second seed crystal 300 are joined so that the thirteenth side surface 341 and the sixth side surface 322 are in facing contact with each other to obtain the substrate 1000, or the first seed crystal 200 and the second seed crystal 300 are joined so that the fifth side surface 321 and the fourteenth side surface 342 are in facing contact with each other to obtain the substrate 1000. The resulting substrate 1000 has dimensions of 1000 μm 150 μm, where 1000 μm represents the length, 1000 μm represents the width, and 150 μm represents the height, i.e., the second height h, i.e., the height of the resulting substrate 1000 is one-half the height of the single crystal diamond seed 100 and the width is twice the width of the original single crystal diamond seed 100.
Except for the above differences, the other steps can be performed with reference to the steps of the first embodiment, and are not further described herein.
EXAMPLE III
Fig. 6 shows a substrate 1000, a method for splicing the substrate 1000, and a method for manufacturing single crystal diamond according to this embodiment.
Referring to fig. 6 and 1, the method for splicing the substrates 1000 includes the following steps:
s30, providing the single crystal diamond seed crystal 100 as in the first embodiment, which will not be described herein.
S31 is the same as step S11 of the first embodiment, and will not be described herein again.
S32 is the same as step S12 of the first embodiment, and will not be described herein again.
S33, bisect the first height H on the second circumferential surface 32 or the fourth circumferential surface 34 to obtain a bisector 35, the bisector 35 in this embodiment is a trisection 352, and treat the trisection 352 with a mark 36 to obtain the trisection 352 and the mark 36 partially covering the trisection 352.
S34, cutting the single crystal diamond seed crystal 100 along the trisection line 352, such that the single crystal diamond seed crystal 100 is cut into the first seed crystal 200, the second seed crystal 300 and the third seed crystal 400, and the cut first seed crystal 200, the second seed crystal 300 and the third seed crystal 400 are all the same in height, i.e., all h (the second height), and the first circumferential surface 31 is cut into the first side surface 311, the second side surface 312 and the third side surface 313, and the third circumferential surface 33 is cut into the fifth side surface 321, the sixth side surface 322 and the seventh side surface 323, wherein the first side surface 311 and the fifth side surface 321 are located on the first seed crystal 200, and the first side surface 311 and the fifth side surface 321 are opposite; the second side 312 and the sixth side 322 are positioned on the second seed crystal 300, and the second side 312 and the sixth side 322 are opposite; the third side 313 and the seventh side 323 are positioned on the third seed crystal 400, and the third side 313 and the seventh side 323 are opposite; meanwhile, the mark 36 is cut into a first mark 361, a second mark 362 and a third mark 363, and the first mark 361 is located on the first seed crystal 200, the second mark 362 is located on the second seed crystal 300, and the third mark 363 is located on the third seed crystal 400.
In some embodiments, the first, second and third cut seeds 200, 300 and 400 all have cut faces, i.e., the first seed 200 has a first cut face 201, the second seed 300 has a second cut face 301, and the third seed 400 has a third cut face 401 and a fourth cut face 402. Because each cut surface obtained by cutting may be uneven, the method can further comprise the step of performing fine grinding or polishing treatment on the first cut surface 201, the second cut surface 301, the third cut surface 401 and the fourth cut surface 402 before splicing, so that the roughness of the first cut surface 201, the roughness of the second cut surface 301, the roughness of the third cut surface 401 and the roughness of the fourth cut surface 402 are not more than 0.8nm and are all parallel to the bottom surface 1, the method is favorable for reducing the surface defects of the first seed crystal 200, the second seed crystal 300 and the third seed crystal 400, and further favorable for splicing and epitaxial growth.
S35, the first seed crystal 200, the second seed crystal 300, and the third seed crystal 400 are joined in a direction perpendicular to the second height h, and the crystal orientations of the joined first seed crystal 200, second seed crystal 300, and third seed crystal 400 are all the same, thereby obtaining the substrate 1000. The resulting substrate 1000 has dimensions of 3000 μm × 500 μm × 100 μm, where 3000 μm denotes the length, 500 μm denotes the width, and 100 μm denotes the height, i.e., the second height H, H ═ 3H.
Specifically, since the first seed crystal 200, the second seed crystal 300, and the third seed crystal 400 are cut from the single crystal diamond seed crystal 100 on the second circumferential surface 32 along the trisection line 352 of the first height H, the first side 311 on the first seed crystal 200, the second side 312 on the second seed crystal 300, and the third side 313 of the third seed crystal 400 all face in the same direction; the ninth side surface 331 of the first seed crystal 200, the tenth side surface 332 of the second seed crystal 300, and the eleventh side surface 333 of the third seed crystal 400 are all oriented in the same direction, and the first seed crystal 200, the second seed crystal 300, and the third seed crystal 400 are joined so that the first side surface 311 and the eleventh side surface 333 are in facing contact with each other and the third side surface 313 and the tenth side surface 332 are in facing contact with each other during joining, thereby obtaining the substrate 1000. In some embodiments, the substrate 1000 may be obtained by bonding the first seed crystal 200, the second seed crystal 300, and the third seed crystal 400 so that the ninth side surface 331 and the third side surface 313 face each other and the second side surface 312 and the eleventh side surface 333 face each other. Alternatively, the substrate 1000 can be obtained by attaching the first side 311 and the tenth side 332 to each other and attaching the second side 312 and the eleventh side 333 to each other.
The substrate 1000 has a bottom surface and a top surface, wherein the bottom surface is formed by splicing the bottom surface 1, the second cutting surface 301 and the fourth cutting surface 402 of the single crystal diamond seed crystal 100; and the top surface is formed by the top surface 2 of the single crystal diamond seed crystal 100, the first cutting surface 201 and the third cutting surface 401 in a splicing manner.
In some embodiments, two splicing surfaces spliced with each other between the first seed crystal 200 and the third seed crystal 400 are parallel to each other, two splicing surfaces spliced with each other between the second seed crystal 300 and the third seed crystal 400 are parallel to each other, the splicing surfaces of the first seed crystal 200 and the third seed crystal 400 are perpendicular to the bottom surface and/or the top surface of the substrate 1000, and the splicing surfaces of the third seed crystal 400 and the second seed crystal 300 are perpendicular to the bottom surface and/or the top surface of the substrate 1000, thereby facilitating the improvement of the splicing effect.
In some embodiments, the substrate 1000 obtained in steps S20 to S25 has a gap of less than 5.0nm at a portion where the first seed crystal 200 and the third seed crystal 400 are joined to each other and a gap of less than 5.0nm at a portion where the second seed crystal 300 and the third seed crystal 400 are joined to each other, thereby facilitating epitaxial growth of large-sized single crystal diamond on the top surface of the substrate 1000 or the bottom surface of the substrate 1000.
In this embodiment, a method for preparing a single crystal diamond 3000 is further provided on the basis of obtaining the substrate 1000, which is specifically referred to fig. 2 and will not be described herein again. The size of the obtained single crystal diamond 3000 was 3000 μm × 500 μm × X μm, where 3000 μm represents a length, 500 μm represents a width, X represents a height, and X is determined according to the time of epitaxial growth.
Example four
Referring to fig. 6 and 7, the difference between the third embodiment and the third embodiment is that in the third embodiment, at least the first circumferential surface 31 and the third circumferential surface 33 are polished, and the second circumferential surface 32 is marked, and during the splicing, the first seed crystal 200, the second seed crystal 300, and the third seed crystal 400 are spliced to obtain the substrate 1000 in a manner that the first side surface 311 and the eleventh side surface 333 are attached to each other in an opposite manner, and the third side surface 313 and the tenth side surface 332 are attached to each other in an opposite manner; or the first seed crystal 200, the second seed crystal 300 and the third seed crystal 400 are spliced in such a manner that the ninth side surface 331 and the third side surface 313 are attached facing each other and the second side surface 312 and the eleventh side surface 333 are attached facing each other, thereby obtaining the substrate 1000; in the present embodiment, at least the second circumferential surface 32 and the fourth circumferential surface 34 are polished, and at the same time, the marking process is performed on the first circumferential surface 31 or the third circumferential surface 33, the second circumferential surface 32 is cut into a fifth side surface 321, a sixth side surface 322 and a seventh side surface 323, the fourth circumferential surface 34 is cut into a thirteenth side surface 341, a fourteenth side surface 342 and a fifteenth side surface 343, the fifth side surface 321 and the thirteenth side surface 341 are positioned on the first seed crystal 200, the sixth side surface 322 and the fourteenth side surface 342 are positioned on the second seed crystal 300, the seventh side surface 323 and the fifteenth side surface 343 are positioned on the third seed crystal 400, and then the first seed crystal 200, the second seed crystal 300 and the third seed crystal 400 are joined in such a manner that the thirteenth side surface 341 and the seventh side surface 323 are directly bonded and the sixth side surface 322 is directly bonded to the fifteenth side surface 343 to obtain the substrate 1000, or the fifth side surface 321, the fifteenth side surface 343 are directly bonded, The first seed crystal 200, the second seed crystal 300 and the third seed crystal 400 are spliced in a manner that the twelfth side 342 and the seventh side 323 are just attached to each other, so that the substrate 1000 is obtained. The resulting substrate 1000 after splicing has dimensions of 1000 μm 1500 μm 100 μm, where 1000 μm represents the length, 1500 μm represents the width, and 100 μm represents the height, i.e., the second height h, i.e., the height of the resulting substrate 1000 after splicing is one-third the height of the single crystal diamond seed 100 and the width is three times the width of the original single crystal diamond seed 100.
Except for the above differences, the other steps can be performed with reference to the steps of the third embodiment, and detailed description thereof is omitted.
EXAMPLE five
The embodiment provides a substrate 1000, a splicing method of the substrate 1000 and a preparation method of single crystal diamond.
Referring to fig. 8 and fig. 1, the method for splicing the substrates 1000 includes the following steps:
s50, providing the single crystal diamond seed crystal 100 as in the first embodiment, which will not be described herein.
S51 is the same as step S11 of the first embodiment, and will not be described herein again.
S52 is the same as step S12 of the first embodiment, and will not be described herein again.
S53, equally dividing the first height H on the second circumferential surface 32 or the fourth circumferential surface 34 to obtain a bisector 35, wherein the bisector 35 in this embodiment is a bisector 353, and processing the bisector 353 with a mark 36 to obtain the bisector 353 and the mark 36 partially covering the bisector 353.
S54, cutting the single crystal diamond seed crystal 100 along the bisector 353 such that the single crystal diamond seed crystal 100 is cut into the first, second, third and fourth seed crystals 200, 300, 400 and 500, and the cut first, second, third and fourth seed crystals 200, 300, 400 and 500 all have a height, all of the four being the same, i.e., all being h (the second height), and the first circumferential surface 31 is cut into the first, second, third and fourth side surfaces 311, 312, 313 and 314; the third circumferential surface 33 is cut into a ninth side 331, a tenth side 332, an eleventh side 333, and a twelfth side 334, wherein the first side 311 and the ninth side 331 are located on the first seed crystal 200, and the first side 311 and the ninth side 331 are opposite to each other; the second side 312 and the tenth side 332 are positioned on the second seed crystal 300, and the second side 312 and the tenth side 332 are opposite; the third side 313 and the eleventh side 333 are positioned on the third seed crystal 400, and the third side 313 and the eleventh side 333 are opposite; the fourth side 314 and the twelfth side 334 are positioned on the fourth seed crystal 500, and the fourth side 314 and the twelfth side 334 are opposite; meanwhile, the mark 36 is cut into a first mark 361, a second mark 362, a third mark 363, and a fourth mark 364, and the first mark 361 is located on the first seed crystal 200, the second mark 362 is located on the second seed crystal 300, the third mark 363 is located on the third seed crystal 400, and the fourth mark 364 is located on the fourth seed crystal 500.
In some embodiments, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400 and the fourth seed crystal 500 obtained by cutting all have cutting faces, i.e. the first seed crystal 200 has a first cutting face 201, the second seed crystal 300 has a second cutting face 301, the third seed crystal 400 has a third cutting face 401 and a fourth cutting face 402, and the fourth seed crystal 500 has a fifth cutting face 501 and a sixth cutting face 502. In some embodiments, since each of the cut surfaces may not be perfectly flat after cutting, the method further comprises the step of performing finish grinding or polishing treatment on the first cut surface 201, the second cut surface 301, the third cut surface 401, the fourth cut surface 402, the fifth cut surface 501 and the sixth cut surface 502, so that the roughness of each of the first cut surface 201, the second cut surface 301, the third cut surface 401, the fourth cut surface 402, the fifth cut surface 501 and the sixth cut surface 502 is not more than 0.8nm and is parallel to the bottom surface 1, which is beneficial to reducing surface defects of the first seed crystal 200, the second seed crystal 300, the third seed crystal 400 and the fourth seed crystal 500, and is further beneficial to splicing and epitaxial growth.
S55, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 are joined in a direction perpendicular to the second height h, and the crystal orientation of the first seed crystal 200, the crystal orientation of the second seed crystal 300, the crystal orientation of the third seed crystal 400, and the crystal orientation of the fourth seed crystal 500 joined to each other are all the same, thereby obtaining the substrate 1000. The substrate 1000 has dimensions 4000 μm × 500 μm × 75 μm, where 4000 μm denotes the length, 500 μm denotes the width, and 75 μm denotes the height, i.e., the second height H, where H is 4H.
Specifically, since the first seed crystal 200, the second seed crystal 300, the third seed crystal 400 and the fourth seed crystal 500 are obtained by cutting the single crystal diamond seed crystal 100 on the second circumferential surface 32 along the bisector 353 of the first height H, the first side surface 311 on the first seed crystal 200, the second side surface 312 on the second seed crystal 300, the third side surface 313 of the third seed crystal 400 and the fourth side surface 314 of the fourth seed crystal 500 all face the same direction; the ninth side 331 of the first seed crystal 200, the tenth side 332 of the second seed crystal 300, the eleventh side 333 of the third seed crystal 400, and the twelfth side 334 of the fourth seed crystal 500 all face in the same direction, and when the first side 311 and the twelfth side 334 are attached facing each other, the fourth side 314 and the eleventh side 333 are attached facing each other, and the third side 313 and the tenth side 332 are attached facing each other, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 are joined together, thereby obtaining the substrate 1000. In some embodiments, the substrate 1000 may be obtained by splicing the fourth seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 in such a manner that the ninth side 331 and the fourth side 314 are attached facing each other, the twelfth side 334 and the third side 313 are attached facing each other, and the tenth side 333 and the second side 312 are attached facing each other. Or the substrate 1000 is obtained by splicing the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 in such a manner that the ninth side 331 and the third side 313 are attached facing each other, the eleventh side 333 and the fourth side 314 are attached facing each other, and the twelfth side 334 and the second side 312 are attached facing each other. Of course, the method is not limited to these splicing methods, and other substrates 1000 with uniform crystal orientation can be obtained by splicing the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500.
The substrate 1000 has a bottom surface and a top surface, wherein the bottom surface is formed by the bottom surface 1 of the single crystal diamond seed crystal 100 (in this case, the bottom surface of the first seed crystal 200), the second cutting surface 301, the fourth cutting surface 402, and the sixth cutting surface 502 in a pieced manner; the top surface of the substrate 1000 is pieced together by the first cut surface 201, the fifth cut surface 501, the third cut surface 401, and the top surface 2 of the single crystal diamond seed crystal 100 (in this case, the top surface of the second seed crystal 300).
In some embodiments, two splicing surfaces spliced with each other between the first seed crystal 200 and the fourth seed crystal 500 are parallel to each other, two splicing surfaces spliced with each other between the second seed crystal 300 and the third seed crystal 400 are parallel to each other, two splicing surfaces spliced with each other between the third seed crystal 400 and the fourth seed crystal 500 are perpendicular to the bottom surface of the substrate 1000, and thus the splicing effect is improved.
In some embodiments, in the substrate 1000 obtained in steps S30 to S35, the gap between the joint portion of the first seed crystal 200 and the fourth seed crystal 500 is less than 5.0nm, the gap between the joint portion of the second seed crystal 300 and the third seed crystal 400 is less than 5.0nm, and the gap between the joint portion of the third seed crystal 400 and the fourth seed crystal 500 is less than 5.0nm, so that the epitaxial growth of the large-size single crystal diamond on the top surface of the substrate 1000 or the bottom surface of the substrate 1000 is facilitated, and the defects of the large-size single crystal diamond at the joint portion are reduced.
In this embodiment, a method for preparing a single crystal diamond is further provided on the basis of obtaining the substrate 1000, which specifically refers to fig. 2 and will not be described herein again. The size of the obtained single crystal diamond 3000 was 4000 μm × 500 μm × X μm, where 4000 μm represents a length, 500 μm represents a width, and X represents a height, which was determined according to the time of epitaxial growth.
EXAMPLE six
Referring to fig. 9 and 8, the difference between the fifth embodiment and the fifth embodiment is that in the fifth embodiment, at least the first circumferential surface 31 and the third circumferential surface 33 are polished, and the second circumferential surface 32 is marked, and during the splicing, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 are spliced in such a manner that the first lateral surface 311 and the twelfth lateral surface 334 are attached to face each other, the fourth lateral surface 314 and the eleventh lateral surface 333 are attached to face each other, and the third lateral surface 313 and the tenth lateral surface 332 are attached to face each other, or in such a manner that the ninth lateral surface 331 and the fourth lateral surface 314 are attached to face each other, the twelfth lateral surface 334 and the third lateral surface 313 are attached to face each other, and the tenth lateral surface 333 and the second lateral surface 312 are attached to face each other; in the present embodiment, at least the second circumferential surface 32 and the fourth circumferential surface 34 are polished while the marking process is performed on the first circumferential surface 31 or the third circumferential surface 33, the second circumferential surface 32 is cut into the fifth side surface 321, the sixth side surface 322, the seventh side surface 323, and the eighth side surface 324, the fourth circumferential surface 34 is cut into the thirteenth side surface 341, the fourteenth side surface 342, the fifteenth side surface 343, and the sixteenth side surface 344, the fifth side surface 321 and the thirteenth side surface 341 are located on the first seed crystal 200, the sixth side surface 322 and the fourteenth side surface 342 are located on the second seed crystal 300, the seventh side surface 323 and the fifteenth side surface 343 are located on the third seed crystal 400, and the eighth side surface 324 and the sixteenth side surface 344 are located on the fourth seed crystal 500. During the splicing, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400 and the fourth seed crystal 500 are spliced in a manner that the thirteenth side surface 341 and the eighth side surface 324 are attached in a facing manner, the sixteenth side surface 344 and the seventh side surface 323 are attached in a facing manner, and the fifteenth side surface 343 and the sixth side surface 322 are attached in a facing manner, so as to obtain the substrate 1000. Of course, the substrate 1000 may be obtained by splicing the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 in other arrangements and combinations, as long as it is possible to ensure that the crystal orientations of the substrate 1000 are uniform and the sizes of the spliced substrate 1000 are 1000 μm × 2000 μm × 75 μm. In the substrate 1000, 1000 μm represents a length, 2000 μm represents a width, and 75 μm represents a height, i.e., a second height h, i.e., the height of the spliced substrate 1000 is one-fourth of the height of the single crystal diamond seed 100, and the width is four times the width of the original single crystal diamond seed 100.
Except for the above differences, the remaining steps can be performed with reference to the steps in the fifth embodiment, and are not further described herein.
EXAMPLE seven
As shown in fig. 10 to 11, the present embodiment provides a substrate 1000, a method of splicing the substrate 1000, and a method of producing single crystal diamond.
Referring to fig. 10, fig. 1 and fig. 8, the method for splicing the substrates 1000 includes the following steps:
s70, providing the single crystal diamond seed crystal 100 as in the first embodiment, which will not be described herein.
S71 is the same as step S11 of the first embodiment, and will not be described herein again.
S72, polishing the first circumferential surface 31, the second circumferential surface 32, the third circumferential surface 33, and the fourth circumferential surface 34 to reduce the roughness of the first circumferential surface 31, the second circumferential surface 32, the third circumferential surface 33, and the fourth circumferential surface 34, which is the same as step S12 in the first embodiment and is not repeated herein.
S73, performing quartering process on the first height H, which is the same as step S53 in the fifth embodiment and will not be described herein again.
S74, cutting the single crystal diamond seed crystal 100, which is the same as the step S54 of the fifth embodiment and is not repeated herein.
S75, the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500 are joined in a direction perpendicular to the second height h, and the crystal orientation of the first seed crystal 200, the crystal orientation of the second seed crystal 300, the crystal orientation of the third seed crystal 400, and the crystal orientation of the fourth seed crystal 500 joined to each other are all the same, thereby obtaining the substrate 1000. The dimensions of the substrate 1000 are 2000 μm × 1000 μm × 75 μm, where 2000 μm denotes the length, 1000 μm denotes the width, and 75 μm denotes the height, i.e., the second height H, where H is 4H.
Specifically, since the first seed crystal 200, the second seed crystal 300, the third seed crystal 400 and the fourth seed crystal 500 are obtained by cutting the single crystal diamond seed crystal 100 on the second circumferential surface 32 along the bisector 353 of the first height H, the first side surface 311 on the first seed crystal 200, the second side surface 312 on the second seed crystal 300, the third side surface 313 of the third seed crystal 400 and the fourth side surface 314 of the fourth seed crystal 500 all face the same direction; the fifth side 321 on the first seed crystal 200, the sixth side 322 on the second seed crystal 300, the seventh side 323 of the third seed crystal 400 and the eighth side 324 of the fourth seed crystal 500 all face in the same direction; the ninth side 331 on the first seed crystal 200, the tenth side 332 on the second seed crystal 300, the eleventh side 333 on the third seed crystal 400, and the twelfth side 334 on the fourth seed crystal 500 all face in the same direction; the thirteenth side 341 on the first seed crystal 200, the fourteenth side 342 on the second seed crystal 300, the fifteenth side 343 on the third seed crystal 400, and the sixteenth side 344 on the fourth seed crystal 500 all face in the same direction; in the case of the alignment, the substrate 1000 is obtained by aligning the first side 311 and the twelfth side 334, the third side 313 and the tenth side 332, the thirteenth side 341 and the sixth side 322, and the sixteenth side 344 and the seventh side 323. The resulting substrate 1000 has a bottom surface and a top surface, wherein the bottom surface is pieced together by the bottom surface 1 of the single crystal diamond seed crystal 100 (in this case, the bottom surface of the first seed crystal 200), the second cutting surface 301, the fourth cutting surface 402, and the sixth cutting surface 502; the top surface of the substrate 1000 is formed by splicing the first cut surface 201, the top surface 2 of the single crystal diamond seed crystal 100 (in this case, the top surface of the second seed crystal 300), the third cut surface 401, and the fifth cut surface 501, and the height from the top surface of the substrate 1000 to the bottom surface of the substrate 1000 is the second height h.
Fig. 11 shows a perspective view of the resulting substrate 1000, and as can be seen from fig. 11, the first mark 361 and the fourth mark 364 are located on the same outer side of the substrate 1000, while the second mark 362 and the third mark 363 are located on the mating surface of the substrate 1000.
In some embodiments, two splicing surfaces spliced with each other between the first seed crystal 200 and the fourth seed crystal 500 are parallel to each other, two splicing surfaces spliced with each other between the second seed crystal 300 and the third seed crystal 400 are parallel to each other, two splicing surfaces of the first seed crystal 200 and the second seed crystal 300 are parallel to each other, two splicing surfaces of the third seed crystal 400 and the fourth seed crystal 500 are perpendicular to the bottom surface of the substrate 1000, and thus the splicing effect is improved.
In some embodiments, the substrate 1000 obtained in steps S40 to S45 has a gap between the portions where the first seed crystal 200 and the fourth seed crystal 500 are joined to each other of less than 5.0nm, a gap between the portions where the second seed crystal 300 and the third seed crystal 400 are joined to each other of less than 5.0nm, a gap between the portions where the first seed crystal 200 and the second seed crystal 300 are joined to each other of less than 5.0nm, and a gap between the portions where the third seed crystal 400 and the fourth seed crystal 500 are joined to each other of less than 5.0nm, thereby facilitating epitaxial growth of large-sized single crystal diamond on the top surface of the substrate 1000 or the bottom surface of the substrate 1000. Of course, the present embodiment is not limited to this splicing manner, and other substrates 1000 having uniform crystal orientation may be obtained by splicing the first seed crystal 200, the second seed crystal 300, the third seed crystal 400, and the fourth seed crystal 500.
In this embodiment, a method for preparing a single crystal diamond is further provided on the basis of obtaining the substrate 1000, which specifically refers to fig. 2 and will not be described herein again. The size of the obtained single crystal diamond 3000 was 2000 μm × 1000 μm × X μm, where 2000 μm represents a length, 1000 μm represents a width, X represents a height, and X is determined according to the time of epitaxial growth.
While the foregoing is directed to embodiments of the present invention, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the invention.