Composite wafer, integration method and applications thereof

Abstract

The present application relates to a kind of composite wafer and its integrated method and application, the integrated method includes the following steps: on the hetero-substrate of surface roughness≤0.5nm, warping≤3 μm, epitaxial growth diamond wafer;Adhesive is used on the growth surface of diamond wafer Adhesion temporary carrier, then remove hetero-substrate, expose the nucleation surface of diamond wafer, wherein, the Young's modulus of temporary carrier≥300GPa and thermal expansion coefficient<9.9×10 ‑6 / ℃;The nucleation surface of diamond wafer is bonded with semiconductor wafer;Remove adhesive and temporary carrier, obtain composite wafer.The integrated method of the present application does not need to polish and grind diamond wafer, and then the size and thickness of diamond wafer also have no special requirements, can be selected according to needs, not only reduce the production difficulty and cost, and the composite wafer bonded is more widely applicable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, in particular to a composite wafer and an integration method and application thereof. BACKGROUND

[0002] With the rapid development of semiconductor devices towards high power density and high frequency, thermal management has become a core challenge restricting the performance and reliability of semiconductor devices. Wide bandgap semiconductor materials represented by gallium nitride (GaN) and silicon carbide (SiC) have shown significant advantages in high frequency and high temperature scenarios, but the increase in power density has exacerbated the problem of local heat accumulation. Traditional heat dissipation materials such as copper and silver are difficult to meet the demand due to insufficient thermal conductivity, while diamond is considered an ideal heat dissipation substrate due to its ultra-high thermal conductivity (>2000 W / m·K), low thermal expansion coefficient and excellent dielectric properties.

[0003] However, direct epitaxial growth of semiconductors on diamond requires a high temperature environment of more than 1000℃, which easily leads to interfacial atomic diffusion and defect generation. In addition, diamond has a cubic crystal structure, while nitrides such as GaN and AlN have a hexagonal wurtzite structure, resulting in a serious lattice mismatch between the two, which increases the semiconductor defect density and interfacial thermal resistance. At the same time, the difference in thermal expansion coefficient between diamond and hetero-materials such as GaN and AlN also easily causes interfacial stress, causing diamond to warp or semiconductors to crack.

[0004] To this end, the prior art generally first epitaxially grows a diamond wafer on a hetero-substrate, and grinds and polishes the growth surface of the diamond wafer to make its surface roughness meet the requirements of the bonding process, and then bonds it with a semiconductor wafer, which can solve the above problems. However, diamond is the hardest material known, and it is difficult to process. The larger the size of the diamond, the more difficult it is to process. It is very difficult to meet this demand and the cost is extremely high. At the same time, in order to facilitate polishing and bonding, the thickness of the diamond wafer needs to be more than 500μm, which greatly limits the application of the composite wafer obtained after bonding in semiconductor devices. SUMMARY

[0005] Therefore, it is necessary to provide a composite wafer and an integration method and application thereof to solve the above problems. The integration method does not require polishing and processing of the diamond wafer, and does not have special requirements for the size and thickness of the diamond wafer, which not only reduces the production difficulty and cost, but also makes the composite wafer obtained by bonding more suitable.

[0006] An integration method of a composite wafer, comprising the following steps:

[0007] epitaxially growing a diamond wafer on a hetero-substrate, wherein the surface roughness of the hetero-substrate is less than or equal to 0.5nm, and the warpage is less than or equal to 3μm;

[0008] bonding a temporary carrier on the growth surface of the diamond wafer using an adhesive, and removing the heterogeneous substrate to expose the nucleation surface of the diamond wafer, wherein the temporary carrier has a Young's modulus greater than or equal to 300 GPa and a thermal expansion coefficient less than 9.9 x 10 -6 / ℃;

[0009] bonding the nucleation surface of the diamond wafer to a semiconductor wafer;

[0010] removing the adhesive and the temporary carrier to obtain a composite wafer.

[0011] In one embodiment, the temporary carrier is selected from a ceramic carrier.

[0012] In one embodiment, the temporary carrier is selected from one of an alumina ceramic carrier, an aluminum nitride ceramic carrier, or a silicon carbide ceramic carrier.

[0013] In one embodiment, the thickness of the temporary carrier is 10 mm to 50 mm.

[0014] In one embodiment, in the step of bonding a temporary carrier on the growth surface of the diamond wafer using an adhesive, the thickness of the adhesive layer after bonding is 1 mm to 3 mm.

[0015] In one embodiment, in the step of bonding a temporary carrier on the growth surface of the diamond wafer using an adhesive, a pressure of 10 Newton to 50 Newton is used during bonding.

[0016] In one embodiment, the adhesive is selected from at least one of a hot melt adhesive and a light-cured adhesive.

[0017] In one embodiment, the heterogeneous substrate has a warpage less than or equal to 1 μm.

[0018] A composite wafer obtained by the integrated method.

[0019] Use of the composite wafer in a semiconductor device.

[0020] In the integrated method of the present application, when the diamond wafer is epitaxially grown on the hetero-substrate, the surface roughness and flatness of the nucleation surface of the obtained diamond wafer can be controlled by controlling the surface roughness and warping degree of the hetero-substrate, so as to directly meet the requirements of the bonding process. Meanwhile, the residual stress of the diamond wafer can be overcome by selecting the temporary carrier, so as to avoid warping or cracking of the diamond wafer during the transfer. Therefore, the integrated method of the present application does not need to polish and grind the diamond wafer, and thus the size and thickness of the diamond wafer are not required to be special, and can be selected according to the requirements. The integrated method of the present application not only reduces the production difficulty and cost, but also has wider applicability of the obtained composite wafer. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0022] Figure 1 The flowchart of the integrated method of the composite wafer of the present application.

[0023] In the figure: 10, hetero-substrate; 20, diamond wafer; 30, adhesive layer; 40, temporary carrier; 50, semiconductor wafer. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of the present application, the present application will be described in more detail below. However, it should be understood that the present application can be realized in many different forms, and is not limited to the embodiments or examples described herein. On the contrary, the purpose of providing these embodiments or examples is to make the disclosure of the present application more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments or examples only and is not intended to be limiting of the present application. As used herein, the term "and / or" is an optional range that includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, including any two related listed items, any more related listed items, or all related listed items.

[0026] In the present application, when numerical ranges are referred to, unless otherwise indicated, the numerical range is considered continuous along the entire range including minimum and maximum values, and every value between the minimum and maximum values. Further, when ranges are provided for a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are to be understood as being inclusive of any and all sub-ranges subsumed therein.

[0027] As shown in the figure, the integrated method of the composite wafer provided by the present application comprises the following steps: Figure 1

[0028] Epitaxially growing a diamond wafer 20 on a hetero-substrate 10;

[0029] Bonding a temporary carrier 40 on the growth surface of the diamond wafer 20 by using an adhesive, and then removing the hetero-substrate 10 to expose the nucleation surface of the diamond wafer 20;

[0030] Bonding the nucleation surface of the diamond wafer 20 with a semiconductor wafer 50;

[0031] Removing the adhesive and the temporary carrier 40 to obtain a composite wafer.

[0032] In the process of epitaxially growing the diamond wafer 20 on the hetero-substrate 10, the interface of the initial nucleation growth on the surface of the hetero-substrate 10 is the nucleation surface, and the free surface formed in the process of continuous deposition and thickening is the growth surface. The surface roughness and flatness of the growth surface are uncontrollable, while the nucleation surface can inherit the surface roughness and flatness of the hetero-substrate 10. Therefore, by controlling the surface roughness of the hetero-substrate 10 to be less than or equal to 0.5 nm and the warping degree to be less than or equal to 3 μm, the surface roughness and flatness of the nucleation surface of the diamond wafer 20 can be controlled to directly meet the requirements of the bonding process. Thus, when the nucleation surface of the diamond wafer 20 is bonded with the semiconductor wafer 50, the diamond wafer 20 does not need to be polished and processed, which greatly reduces the production difficulty and cost, and further, the diamond wafer 20 does not have a minimum thickness requirement, and its size and thickness can be selected according to actual needs, which has strong applicability.

[0033] Optionally, the hetero-substrate 10 can be selected from a single crystal silicon substrate and the like, and the surface roughness and warping degree of the hetero-substrate 10 mainly refer to the surface roughness and warping degree used for epitaxially growing the diamond wafer 20, so that the surface roughness and flatness of the nucleation surface of the diamond wafer 20 obtained by epitaxial growth can meet the requirements of the bonding process, and at the same time, the nucleation surface of the diamond wafer 20 can be prevented from warping or cracking during transfer. ​

[0034] Further, the warpage of the hetero-substrate 10 is preferably less than or equal to 2 μm, and more preferably less than or equal to 1 μm, so that a nucleation surface with better flatness can be obtained, and the nucleation surface of the diamond wafer 20 can be better prevented from warping or breaking during transfer.

[0035] Since the diamond wafer 20 does not need to be polished and processed in the present application, and the diamond wafer 20 can be better prevented from warping or breaking during transfer, the size and thickness of the diamond wafer 20 are not particularly required and can be selected as needed. Of course, in order to better play a role in heat dissipation, the thickness of the diamond wafer 20 is preferably greater than or equal to 1 μm.

[0036] Further, when the diamond wafer 20 is epitaxially grown on the hetero-substrate 10, the corresponding hetero-substrate 10 can be selected according to the size of the diamond wafer 20. Since the residual stress of the diamond wafer 20 increases with the increase of the size, the greater the size of the diamond wafer 20 required, the greater the thickness of the hetero-substrate 10 used.

[0037] However, due to the residual stress of the diamond wafer 20 itself, the diamond wafer 20 is prone to warping and breaking, and it is difficult to obtain the nucleation surface of the diamond wafer 20 and bond it with the semiconductor wafer 50. To this end, the present application uses an adhesive to bond the temporary carrier 40 to the growth surface of the diamond wafer 20, and controls the Young's modulus of the temporary carrier 40 to be greater than or equal to 300 GPa and the thermal expansion coefficient to be less than 9.9 x 10 -6 / ℃, so that the residual stress of the diamond wafer 20 can be overcome, and the diamond wafer 20 can be better prevented from warping or breaking during transfer.

[0038] Optionally, the temporary carrier 40 is selected from a ceramic carrier, and is further preferably selected from one of an alumina ceramic carrier, an aluminum nitride ceramic carrier or a silicon carbide ceramic carrier, and the adhesive is selected from one of a hot melt adhesive and a light curing adhesive.

[0039] In order to better overcome the residual stress of the diamond wafer 20, the thickness of the temporary carrier 40 is preferably 10 mm-50 mm, and / or in the step of bonding the temporary carrier 40 to the growth surface of the diamond wafer 20 using an adhesive, the thickness of the adhesive layer 30 after bonding is 1 mm-3 mm.

[0040] When the quality of the diamond wafer 20 obtained by epitaxial growth is good, for example, the warping degree is good, in the step of bonding the temporary carrier 40 to the growth surface of the diamond wafer 20 by using the adhesive, the pressure used in the bonding process will not affect the diamond wafer 20 and cause the diamond wafer 20 to be broken. Of course, in order to avoid the diamond wafer 20 from being broken in the bonding process as much as possible, it is preferred that the pressure used in the bonding process is 10 N to 50 N.

[0041] Preferably, the size of the temporary carrier 40 is the same as that of the diamond wafer 20, and the size of the adhesive layer 30 formed after the bonding of the adhesive is also the same as that of the diamond wafer 20, so that the residual stress of the diamond wafer 20 can be better overcome, and the warping or breaking of the diamond wafer 20 can be avoided.

[0042] It should be noted that after the temporary carrier 40 is bonded to the growth surface of the diamond wafer 20 by using the adhesive, the hetero-substrate 10 is removed by at least one of the following methods: laser lift-off, substrate polishing, dry etching, and wet etching, so as to expose the nucleation surface of the diamond wafer 20.

[0043] It can be understood that although the present application does not require the nucleation surface of the diamond wafer 20 to be polished, the bonding surface of the semiconductor wafer 50 still needs to be polished before the nucleation surface of the diamond wafer 20 is bonded to the semiconductor wafer 50, so as to meet the requirements of the bonding process.

[0044] It should be noted that the present application does not have special requirements for the semiconductor wafer 50, which can be a gallium nitride (GaN) wafer, a silicon carbide (SiC) wafer, or the like, and the bonding method includes but is not limited to direct bonding, metal bonding, eutectic bonding, and the like.

[0045] After the bonding is completed, the adhesive and the temporary carrier 40 are removed, and a composite wafer is obtained. The removal method can be heating or using a degreasing agent to separate the adhesive from the diamond wafer 20.

[0046] In summary, the integration method of the present application does not require the diamond wafer 20 to be polished, and thus the size and thickness of the diamond wafer 20 also do not have special requirements and can be selected as required. The integration method not only reduces the production difficulty and cost, but also makes the composite wafer obtained by the bonding have wider applicability.

[0047] Based on this, the present application further provides a composite wafer obtained by using the integration method, which includes a stacked diamond wafer and a semiconductor wafer, for example, a composite wafer of a diamond wafer and a gallium nitride wafer, a composite wafer of a diamond wafer and a silicon carbide wafer, or the like. The semiconductor wafer is stacked on the nucleation surface of the diamond wafer in a bonded manner.

[0048] The application further provides application of the composite wafer in a semiconductor device, and the composite wafer has excellent heat dissipation performance.

[0049] In the following, the composite wafer and the integrated method and application thereof will be further described through the following specific examples.

[0050] Example 1

[0051] A single crystal silicon substrate with a surface roughness of 0.2 nm, a warpage of 1 μm, a thickness of 3 mm and a size of 4 inches is selected. Then, a microwave CVD equipment method is used to crack a mixed gas of methane and hydrogen to deposit a diamond wafer on the single crystal silicon substrate, and the thickness of the diamond wafer is 80 μm.

[0052] An alumina ceramic with a thickness of 15 mm is used as a temporary carrier, and a hot melt adhesive is spin-coated on the surface of the alumina ceramic. Then, the alumina ceramic with the hot melt adhesive is completely attached to the growth surface of the diamond wafer, 30 Newtons of pressure is applied, and the hot melt adhesive is used to bond the alumina ceramic to the growth surface of the diamond wafer. After bonding, the thickness of the hot melt adhesive layer is 1.5 mm.

[0053] The single crystal silicon substrate is removed by a wet etching method to expose the nucleation surface of the diamond wafer. The etching solution is a hydrofluoric acid solution with a concentration of 20% and a temperature of 40℃, and the etching time is 1 hour. After detection, the surface roughness of the nucleation surface of the diamond wafer is 0.5 nm, and the warpage is 50 μm.

[0054] The diamond wafer with the alumina ceramic is placed in an SPM solution prepared by mixing H2SO4 and H2O2 at a ratio of 4:1 at 100℃ for 10 minutes, then washed with deionized water and dried with nitrogen. At the same time, the silicon carbide wafer is polished to a surface roughness of 0.2 nm, then ultrasonically cleaned in acetone and isopropyl alcohol for 5 minutes, and then dried with nitrogen. Then, the cleaned silicon carbide wafer and the diamond wafer with the alumina ceramic are placed in a magnetron sputtering device, the surface is pretreated with oxygen plasma, then a 10 nm Ti metal layer and a 50 nm Au metal layer are sequentially deposited on the surface, then the sample is immediately attached to each other in a clean room after being taken out of the magnetron sputtering device, and then bonded at 300℃, with a pressure of 7 MPa applied during the process for 2 hours, and then taken out after natural cooling to room temperature.

[0055] Then, the sample is heated to 150℃, and toluene is used as a degreasing agent to remove the alumina ceramic and the hot melt adhesive, thereby obtaining a composite wafer in which the diamond wafer and the silicon carbide wafer are stacked.

[0056] Example 2

[0057] A single crystal silicon substrate with a surface roughness of 0.3 nm, a warpage of 1 μm, a thickness of 5 mm, and a size of 6 inches is selected. Then, a microwave CVD apparatus is used to deposit a diamond wafer on the single crystal silicon substrate by pyrolyzing a mixed gas of methane and hydrogen.

[0058] An aluminum nitride ceramic with a thickness of 25 mm is used as a temporary carrier, and a hot melt adhesive is spin-coated on the surface of the aluminum nitride ceramic. Then, the aluminum nitride ceramic with the hot melt adhesive is completely attached to the growth surface of the diamond wafer, and a pressure of 35 Newtons is applied to bond the aluminum nitride ceramic to the growth surface of the diamond wafer using the hot melt adhesive. After bonding, the thickness of the hot melt adhesive layer is 2 mm.

[0059] A portion of the single crystal silicon substrate is removed by laser ablation, and then the remaining single crystal silicon substrate is completely removed by dry etching to expose the nucleation surface of the diamond wafer. In the dry etching, nitrogen trifluoride is used as the etching gas, the flow rate is 100 mL / min, the pressure is 100 Pa, the power is 800 W, and the time is 2 hours. After detection, the surface roughness of the nucleation surface of the diamond wafer is 1 nm, and the warpage is 100 μm.

[0060] The diamond wafer with the aluminum nitride ceramic is placed in an SPM solution prepared by mixing H2SO4 and H2O2 at a ratio of 4:1 at 100°C for 10 minutes, then washed with deionized water and dried with nitrogen. At the same time, the gallium nitride wafer is polished to a surface roughness of 0.3 nm, then ultrasonically cleaned in acetone and isopropyl alcohol for 5 minutes, and then dried with nitrogen. Then, the cleaned silicon carbide wafer and the diamond wafer with the aluminum nitride ceramic are placed in a magnetron sputtering device, and the surface is pretreated with oxygen plasma. Then, a 10-nm-thick Ti metal layer, a 200-nm-thick Cu metal layer, a 5-nm-thick Ti metal layer, and a 20-nm-thick Au metal layer are sequentially deposited on the nucleation surface of the diamond wafer, and a 10-nm-thick Ti metal layer and a 20-nm-thick Au metal layer are sequentially deposited on the surface of the gallium nitride wafer. Then, the samples are immediately attached to each other in a clean room after being taken out of the magnetron sputtering device, and then bonded at 200°C with a pressure of 5 MPa for 2 hours. After natural cooling to room temperature, the samples are taken out.

[0061] Then, the samples are heated to 150°C, and the aluminum nitride ceramic and the hot melt adhesive are removed using acetone as a degreasing agent to obtain a composite wafer in which the diamond wafer and the gallium nitride wafer are stacked.

[0062] Example 3

[0063] A single crystal silicon substrate with a surface roughness of 0.5 nm, a warpage of 3 μm, a thickness of 10 mm, and a size of 8 inches is selected. Then, a microwave CVD apparatus is used to deposit a diamond wafer on the single crystal silicon substrate by pyrolyzing a mixed gas of methane and hydrogen.

[0064] A silicon carbide ceramic with a thickness of 50 mm is used as a temporary carrier, and a hot melt adhesive is spin-coated on the surface of the silicon carbide ceramic. Then, the silicon carbide ceramic with the hot melt adhesive is completely attached to the growth surface of the diamond wafer, and a pressure of 40 N is applied. The silicon carbide ceramic is bonded to the growth surface of the diamond wafer by using a light-cured adhesive. After bonding, the thickness of the hot melt adhesive layer is 2.5 mm.

[0065] A part of the single crystal silicon substrate is removed by a wet etching method, and the remaining single crystal silicon substrate is completely removed by a dry etching method to expose the nucleation surface of the diamond wafer. In the dry etching method, nitrogen trifluoride is used as the etching gas, the flow rate is 100 mL / min, the pressure is 100 Pa, the power is 800 W, and the time is 2 hours. After detection, the surface roughness of the nucleation surface of the diamond wafer is 1 nm, and the warpage is 150 μm.

[0066] The diamond wafer with the silicon carbide ceramic is placed in an SPM solution prepared by mixing H2SO4 and H2O2 at a ratio of 4:1 at 100°C for 10 minutes, then washed with deionized water and dried with nitrogen. At the same time, the gallium nitride wafer is polished to a surface roughness of 0.5 nm, then ultrasonically cleaned in acetone and isopropyl alcohol for 5 minutes, and then dried with nitrogen. Then, the cleaned silicon carbide wafer and the diamond wafer with the silicon carbide ceramic are placed in a magnetron sputtering device, and the surface is pretreated by oxygen plasma. Then, a 10-nm-thick Ti metal layer, a 200-nm-thick Cu metal layer, a 5-nm-thick Ti metal layer, and a 20-nm-thick Au metal layer are sequentially deposited on the nucleation surface of the diamond wafer, and a 10-nm-thick Ti metal layer and a 20-nm-thick Au metal layer are sequentially deposited on the surface of the gallium nitride wafer. Then, the sample is taken out of the magnetron sputtering device and immediately attached to each other in a clean room, and then bonded at 200°C with a pressure of 5 MPa for 2 hours. After natural cooling to room temperature, it is taken out.

[0067] Then, the sample is heated to 150°C, and the aluminum nitride ceramic and the hot melt adhesive are removed using acetone as a degreasing agent to obtain a composite wafer in which the diamond wafer and the gallium nitride wafer are stacked.

[0068] Comparative Example 1

[0069] The difference between the comparative example 1 and the example 1 is only that the surface roughness of the single crystal silicon substrate is 0.8 nm and the warpage is 10 microns. In the comparative example, the surface roughness of the diamond wafer nucleation surface is 1.5 nm and the warpage is 100 microns, which cannot directly meet the requirements of the bonding process and needs to be polished.

[0070] Comparative example 2

[0071] The difference between the comparative example 2 and the example 1 is only that the single crystal silicon wafer with a thickness of 15 mm is used instead of the alumina ceramic as the temporary carrier. It is detected that the surface roughness of the diamond wafer nucleation surface is 1 nm and the warpage is 400 microns, the surface roughness is not affected, but the warpage is increased due to the low Young's modulus and insufficient rigidity of the temporary carrier.

[0072] Comparative example 3

[0073] The difference between the comparative example 3 and the example 1 is only that the molybdenum metal sheet with a thickness of 15 mm is used instead of the alumina ceramic as the temporary carrier, but the diamond wafer is directly broken due to the difference in the thermal expansion coefficient during the transfer process.

[0074] From the above examples and comparative examples, it can be seen that, when the diamond wafer is epitaxially grown on the hetero-substrate, the surface roughness and the flatness of the diamond wafer nucleation surface can be controlled by controlling the surface roughness and the warpage of the hetero-substrate, so that the requirements of the bonding process can be directly met. At the same time, the residual stress of the diamond wafer can be overcome by selecting the temporary carrier, and the warpage or breakage of the diamond wafer during the transfer process can be avoided. Therefore, the integration method of the present application does not need to polish and grind the diamond wafer, and thus the size and thickness of the diamond wafer are not specially required, which can be selected according to the needs, so as to not only reduce the production difficulty and cost, but also make the bonded composite wafer more suitable.

[0075] The technical features of the above examples can be combined arbitrarily, and in order to make the description simple, all possible combinations of the technical features in the above examples are not described, however, as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0076] The above examples only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.

Claims

1. An integration method of a composite wafer, characterized by, The method comprises the following steps: epitaxially growing a diamond wafer on a heterogeneous substrate, wherein the surface roughness of the heterogeneous substrate is less than or equal to 0.5 nm, and the warping degree is less than or equal to 1 μm; bonding a temporary carrier to a growth face of a diamond wafer using a bonding agent, the temporary carrier having a Young's modulus greater than or equal to 300 GPa and a coefficient of thermal expansion less than 9.9 x 10 -6 / °C, the temporary carrier being selected from the group consisting of ceramic carriers, and removing the foreign substrate to expose a nucleation face of the diamond wafer. bonding a nucleation surface of the diamond wafer with a semiconductor wafer; removing the adhesive and the temporary carrier to obtain a composite wafer.

2. The integration method of composite wafers according to claim 1, wherein The temporary carrier is selected from one of an alumina ceramic carrier, an aluminum nitride ceramic carrier, or a silicon carbide ceramic carrier.

3. The integrated method of composite wafer according to claim 1, wherein, The thickness of the temporary carrier is 10 mm-50 mm.

4. The integrated method of composite wafer of claim 1, wherein, In the step of bonding the temporary carrier to the growth surface of the diamond wafer using an adhesive, the thickness of the adhesive layer after bonding is 1 mm-3 mm.

5. The integrated method of composite wafer of claim 1, wherein, In the step of bonding the temporary carrier to the growth surface of the diamond wafer using an adhesive, a pressure of 10 Newton to 50 Newton is used during bonding.

6. The integrated method of composite wafer of claim 1, wherein, The adhesive is selected from at least one of a hot melt adhesive and a light curing adhesive.

7. A composite wafer obtained by the integrated method according to any one of claims 1 to 6.

8. Use of the composite wafer according to claim 7 in a semiconductor device.

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