JP6049571B2 - Method for manufacturing composite substrate having nitride semiconductor thin film - Google Patents

Description

  The present invention relates to a method of manufacturing a composite substrate having a semiconductor layer on a support substrate, free from metal contamination and having few defects in the semiconductor layer.

  Nitride single crystal semiconductors, especially GaN, have a wide band gap, so application to blue LEDs and high power devices are being studied. A GaN thin film is usually manufactured by epitaxially growing GaN on a sapphire substrate having a small difference in lattice constant from GaN. However, defects occur due to a mismatch in lattice constant. In recent years, a single crystal GaN free-standing substrate has been developed for the purpose of preventing such defects. Growing GaN on a GaN free-standing substrate can be expected to reduce defects because there is no difference in lattice constant.

  However, the single crystal GaN free-standing substrate has a problem that the current cost is high. As a measure for reducing the cost, for example, a technique used in SOI, SOS, etc., for example, a light element ion such as hydrogen is ion-implanted into single crystal Si and then bonded to a support substrate such as Si or sapphire to transfer the Si thin film. It is conceivable to apply a smart cut method or the like to a GaN free-standing substrate. By applying this method, the GaN free-standing substrate after the GaN thin film transfer can be reused for the transfer of the GaN thin film, and the cost can be reduced.

  For example, Patent Document 1 describes that an ion-implanted GaN substrate is bonded to a Si substrate, and heat treatment at 800 ° C. or higher is performed to transfer the GaN thin film onto the Si substrate. Non-Patent Documents 1 and 2 describe attempts to bond an ion-implanted GaN substrate and a sapphire substrate.

JP 2006-210660 A O. Moutanabbir et al., ECS Transactions 16 (8), 251-262 (2008) O. Moutanabbir and U. Gosele, Journal of Electronic Materials 39 (5), 482-488 (2010)

However, in Patent Document 1, when heat treatment is performed, separation in the ion-implanted region is not performed, and a problem that the GaN substrate peels off from the Si substrate frequently occurs. Further, in Non-Patent Documents 1 and 2, similarly to Patent Document 1, there is a problem that the substrate is peeled off during the heat treatment. That is, it is stated that ion implantation into a GaN substrate causes warpage of the GaN substrate to be large, and bonding with the support substrate is not performed well, and peeling occurs due to heat treatment after bonding.
As a countermeasure above, it has been studied to improve the warpage of the GaN substrate by ion implantation from both sides of the GaN substrate, but this method does not transfer the thin film to the entire surface of the sapphire substrate, and the number of diameters is at most. Only mm size transfer has been made. In addition, if ion implantation is performed on both surfaces, the warpage is improved, but the number of ion implantations is doubled, which increases costs. Although the surface roughness of the substrate may be considered as another factor that causes the substrate to peel off, when the SiO ₂ layer is provided on the surface of the GaN substrate, the surface roughness is about 0.2 nm, which is a level that can be sufficiently bonded. For this reason, the cause of peeling is large warpage, and it is assumed that peeling occurs due to heat treatment after joining. Thus, it has been difficult to achieve transfer of the GaN thin film to the entire surface of the support substrate only by improving the surface roughness or warpage.
From the above, thin film transfer of a GaN substrate using ion implantation has a problem that transfer over the entire substrate surface is difficult.

As a result of studies by the present inventors, it has been found that a GaN thin film can be transferred to the entire support substrate surface even in a state where there is a warp in which ions are implanted only on one surface of the GaN substrate. In other words, surface activation treatment is performed before bonding and bonding is performed under a constant load to increase the bonding strength. After bonding, bonding is performed when the GaN substrate is peeled off along the ion implantation layer and transferred. It has been found that the GaN thin film can be transferred over the entire support substrate surface without causing separation at the bonding interface.
In one aspect of the present invention, a step of obtaining a nitride semiconductor substrate having an ion implantation layer therein by implanting ions from the surface, wherein the nitride semiconductor substrate has the ion implanted surface as an upper side. At least one of a step having a warp of 10 μm or more and 300 μm or less warped in a convex shape, and the surface of the nitride semiconductor substrate to which the ion implantation is performed and the surface of the support substrate to be bonded to the nitride semiconductor substrate A step of performing a surface activation treatment and the ion-implanted surface of the nitride semiconductor substrate and the surface of the support substrate are overlapped and bonded under a pressure of 1.0 MPa or more and 4.0 MPa or less. And at least a step of peeling the nitride semiconductor substrate along the ion implantation layer and transferring a nitride semiconductor thin film onto the support substrate. A method for manufacturing a composite substrate including a nitride semiconductor thin film on a support substrate can be provided.

  According to the present invention, a nitride semiconductor thin film can be transferred to the entire support substrate surface even when a nitride semiconductor substrate having a warp caused by ion implantation on the surface of the nitride semiconductor substrate is used.

It is a schematic diagram which shows the one aspect | mode of the manufacturing process of the composite substrate concerning this invention.

Examples of the nitride semiconductor substrate to be transferred include a GaN substrate and an AlN substrate, but a GaN substrate is preferable because of its large size as a single crystal substrate. The following describes a GaN wafer.
In the GaN single crystal wafer, either the Ga surface or the N surface can be used as the bonding surface. However, since a Ga surface is usually used for a device, it is preferable to use an N surface as a bonding surface and to use a Ga surface as a surface exposed after transfer.

  The surface of the GaN wafer has a surface roughness RMS (root mean square, JIS B 0601) of preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less. It is preferable for realizing the bonding with the support substrate. Further, if there is a defect such as a pit on the bonding surface, the portion becomes a void after thin film transfer, and therefore it is preferable that there is no defect.

A CMP (chemical mechanical polishing) process is generally used as a method for smoothing the surface of a semiconductor substrate, but this method is used directly on the surface of a GaN wafer to achieve a desired surface roughness RMS and defect-free. This is not easy in the present situation, the yield and the like deteriorate, and the cost is high. Therefore, in order to set the GaN wafer surface to a desired surface roughness RMS with high yield, and to suppress the generation of voids after transfer, the surface to be ion-implanted as the bonding surface of the GaN wafer has SiO ₂ , Si ₃ N ₄ , and It is preferable to provide a film selected from SiO _x N _y (0 <x <2, 0 <y <1.3). The thickness of this film is preferably 10 nm to 10 μm, more preferably 20 nm to 5 μm, and still more preferably 50 nm to 3 μm. If it is less than 10 nm, the effect of improving the surface roughness RMS may be insufficient, and if it exceeds 10 μm, peeling may occur during film formation. As a means for forming a film, chemical vapor deposition methods such as AP-CVD, LP-CVD, PE-CVD, electron beam evaporation, sputtering, or a solution containing a film precursor is spin-coated, dip-coated, A method of forming a film by means selected from slit coating and the like and then converting to a desired film by heat treatment can be used.

  After the above film formation, an annealing treatment may be preferably performed at 800 to 1200 ° C. for film densification and degassing treatment. Further, after the film formation, it is preferable to perform CMP in order to set the surface roughness RMS to the above-described desired surface roughness RMS. By performing CMP on the surface of the film formed on the GaN wafer, it is possible to achieve a desired surface roughness RMS with a high yield. However, when the surface roughness RMS after film formation or after annealing is preferably 1 nm or less, more preferably 0.5 nm or less, and still more preferably 0.3 nm or less, CMP is not particularly required. If the annealing treatment does not affect the surface roughness RMS, the above-described annealing treatment may be performed after CMP.

After forming a film on the surface of the GaN wafer to obtain a desired surface roughness RMS, ions are implanted from the surface to form an ion implantation layer inside the GaN wafer. At this time, a predetermined dose of hydrogen ions (H ⁺ ) or hydrogen molecular ions (H ₂ ⁺ ) is implanted with an implantation energy that can form an ion implantation layer at a desired depth from the surface. As a condition at this time, for example, the implantation energy can be set to 50 to 100 keV. Any ion such as He ion or B ion can be used as long as the same effect can be obtained, and the implantation energy may be appropriately selected. The ion implantation depth depends on the desired thickness of the donor thin film, but can usually be 50 nm to 2000 nm.
When hydrogen ions (H ⁺ ) are used as implanted ions, the dose is preferably, for example, 1.0 × 10 ¹⁶ atoms / cm ^{2 to} 3.0 × 10 ¹⁷ atoms / cm ² . In addition, when hydrogen molecular ions (H ₂ ⁺ ) are used as the implanted ions, the dose is preferably, for example, 5.0 × 10 ¹⁵ atoms / cm ^{2 to} 1.5 × 10 ¹⁷ atoms / cm ² .

  A convex warpage occurs in the GaN wafer after ion implantation when the ion-implanted surface is on the upper side. Warp can be used as an index of warpage. Warp represents the deformation (warpage) of the wafer in the unclamped state evaluated by MF1390 of the SEMI standard. Specifically, the maximum distance and the minimum distance between the three-point reference plane and the wafer surface in the unclamped state For example, it can be measured by FlatMaster200XRA-Wafer (manufactured by Corning Tropel). When using Warp, the warp of the wafer is preferably 300 μm or less. More preferably, it is 100 micrometers or less, More preferably, it is 50 micrometers or less. When Warp is larger than 300 μm, subsequent bonding becomes difficult. The lower limit is 10 μm although it depends on the original substrate Warp, size, and dose of hydrogen ions. The magnitude of the warp can be controlled by, for example, the dose of implanted hydrogen ions, the size of the substrate, the thickness of the substrate, and the like.

The support substrate is selected depending on the purpose and application, but is preferably a substrate different from the nitride semiconductor substrate. Examples of typical substrates include single substrates such as silicon, sapphire, alumina, SiC, AlN, SiN, and diamond. A crystalline or polycrystalline substrate can be mentioned. The polycrystalline substrate may be used as a thin film provided on a substrate such as silicon. Further, the surface roughness RMS of these supporting substrates is also preferably set to a level of roughness RMS that can be bonded in the same manner as the GaN wafer described above. When a polycrystalline substrate or a polycrystalline thin film is used, a film such as SiO _{2 can be} formed on the surface by the above method, and CMP can be performed to reduce the surface roughness RMS.

  In the bonding of the GaN wafer and the support substrate, surface activation treatment is performed on at least one of the bonding surfaces of the GaN wafer and the support substrate before bonding, and then bonding is performed by applying pressure to the bonded surface. It is important that

Examples of the surface activation treatment include plasma treatment, ozone water treatment, UV ozone treatment, and ion beam treatment. For example, when processing with plasma, a cleaned substrate is placed in a vacuum chamber, a plasma gas is introduced under reduced pressure, and then exposed to a high-frequency plasma of about 100 W for about 5 to 10 seconds to plasma-treat the surface. . As the plasma gas, oxygen gas can be used when the surface is oxidized, and hydrogen gas, nitrogen gas, argon gas, or a mixed gas thereof can be used when the surface is not oxidized. By treating with plasma, organic substances on the surface of the substrate are oxidized and removed, and OH groups on the surface are increased and activated. When processing with ozone, ozone gas can be introduced into pure water and the surface can be activated with active ozone. When UV ozone processing is performed, short wavelength UV light (wavelength in the atmosphere or oxygen gas) The surface can be activated by irradiating (approx. 195 nm) and generating active ozone. The ion beam treatment can be performed by exposing an ion beam such as Ar to the surface in a high vacuum (<1 × 10 ⁻⁶ Torr) to expose a dangling bond having high activity.
This treatment is more preferably performed on both the ion-implanted surface of the GaN wafer and the surface of the support substrate to be bonded to the GaN wafer, but only one of them may be performed. If the surface activation treatment is not performed, the bonding force at the bonding surface is weak, peeling between the substrates occurs during the heat treatment, and the transfer of the GaN thin film hardly occurs.

After the surface activation treatment, the ion-implanted surface of the GaN wafer and the surface of the supporting substrate to be bonded to the GaN wafer are overlapped and bonded together under pressure. If no pressure is applied during bonding, the transfer of the GaN thin film occurs only on a part of the support substrate surface. Therefore, in order to transfer the GaN thin film over the entire support substrate surface, not only the surface activation process but also the pressurization is required.
Examples of the pressing method include an isostatic press, a uniaxial press, a press roll, a flat plate press, and a hot press. The pressure for pressurization is preferably 0.5 to 5.0 MPa. More preferably, it is 0.7-4.5 MPa, More preferably, it is 1.0-4.0 MPa. If the pressure is lower than 0.5 MPa, the effect of applying pressure only to a part of the supporting substrate is small, and if it exceeds 5.0 MPa, the substrate may be damaged. The holding time for pressurization varies depending on the pressure, but is preferably 1 to 600 seconds, more preferably 10 to 500 seconds, and further preferably 30 to 400 seconds. If the pressurization time is shorter than 1 second, it may transfer to only a part of the support substrate and the effect of pressurization may be insufficient. Becomes longer.

The bonded substrates may be heat treated as necessary to increase the bonding strength. Depending on the case, heat treatment may be performed while bonding under pressure using a hot press machine or the like in the bonding step, or after the bonding step and before the step of transferring the GaN thin film onto the support substrate. A step of performing heat treatment on the combined substrates may be included.
The heat treatment temperature is preferably 100 to 300 ° C. The heat treatment time is determined according to the heat treatment temperature and the material, and is preferably selected in the range of 10 minutes to 24 hours. If the heat treatment temperature is too high or the heat treatment time is too long, there is a risk of cracking, peeling, or the like. Optionally, the heat treatment can be performed preferably in the presence of argon, nitrogen, helium, or a mixed gas thereof.

After the bonding step, the GaN thin film can be transferred onto the support substrate by peeling the GaN wafer along the ion implantation layer. As a method of performing peeling, peeling by applying visible light irradiation or heat, or peeling by applying a mechanical impact may be mentioned. The method of performing said peeling may be used independently and may be used in combination.
In the case of peeling by visible light irradiation, the ion-implanted layer has a mechanism in which the vicinity of the ion-implanted interface formed inside the GaN wafer is amorphized, so that it easily absorbs visible light and easily accepts energy. Can be embrittled and peeled off. Moreover, this peeling method is preferable because it is simpler than mechanical peeling. The visible light source is preferably a Rapid Thermal Annealer (RTA), a green laser light, or a flash lamp light.
In addition, when mechanical peeling is performed by applying an impact to the ion-implanted layer, there is no possibility that thermal strain, cracking, peeling of the bonded surfaces, and the like accompanying heating occur. The mechanical peeling is preferably by cleavage from one end to the other end. As the cleavage member, a wedge-shaped member, for example, a wedge (wedge) is preferably inserted into the ion implantation layer (implantation interface), and the cleavage is progressed by the deformation by the wedge, and the separation may be performed. When using this method, care should be taken to avoid generation of scratches and particles at the contact portion of the wedge, and substrate cracking due to excessive deformation of the wafer caused by driving the wedge. In order to give an impact to the ion-implanted layer, for example, a jet of a fluid such as a gas or a liquid may be sprayed continuously or intermittently from the side surface of the bonded wafer. If there is no particular limitation.
In this way, the GaN thin film can be transferred to the entire surface of the support substrate even when the wafer is warped by ion implantation into the surface of the GaN wafer.

Although the manufacturing process of the composite substrate concerning this invention is not specifically limited, The one aspect | mode is shown in FIG. According to this, the SiO ₂ film 2 is formed on the surface of the GaN wafer 1, and ions 3 are implanted from the surface to form the ion implantation layer 4 (a). Further, surface activation treatment is performed on the bonding surface 5a of the ion-implanted surface 2a and the sapphire substrate 5 as a support substrate by irradiation with an ion beam 6 (b and c), and these surfaces are opposed to each other, for example, And hold and apply pressure 7 at 250 ° C. (d). Thereafter, a wedge-shaped jig is inserted into the ion implantation layer 4 of the bonded substrate 8, and the GaN wafer 1 b is peeled along the ion implantation layer 4, whereby the GaN thin film 1 a is transferred onto the sapphire substrate 5. 9 can be obtained (e).

<Example 1>
A single crystal GaN wafer having an outer diameter of 2 inches and a thickness of 350 μm was used as the nitride semiconductor substrate, and 300 nm of SiO ₂ was deposited on the N surface side by plasma CVD to form a film. H ⁺ ions were implanted at 2.0 × 10 ¹⁷ atoms / cm ² from the SiO ₂ film surface side of the GaN wafer. The GaN wafer after ion implantation had a convex shape when the ion implantation surface was on the upper side, and Warp was 40 μm. In addition, Warp measured in the state of unclamping using FlatMaster200XRA-Wafer apparatus (made by Corning Tropel). Subsequently, CMP was performed on the surface of the SiO ₂ film on the GaN wafer, and the surface roughness RMS (JIS B 0601) was adjusted to 0.2 nm to obtain a roughness RMS at a level that enables bonding.
A sapphire wafer of the same size as the GaN wafer was used as a support substrate. Surface activation treatment was performed on the SiO ₂ film surfaces of the sapphire wafer and the GaN wafer by ion beam irradiation. Thereafter, the surfaces subjected to the surface activation treatment were opposed to each other, held together at a pressure of 4.0 MPa for 60 seconds using a uniaxial pressure press, and a GaN wafer and a sapphire wafer were bonded to obtain a joined body. After heat-treating this at 250 ° C., the GaN wafer was peeled off by applying a mechanical impact using a wedge-shaped member to obtain a sapphire wafer onto which the GaN thin film was transferred.

<Example 2>
A sapphire wafer to which a GaN thin film was transferred was obtained in the same manner as in Example 1 except that a bonded body was obtained by holding the GaN wafer and the sapphire wafer together at a pressure of 1.0 MPa for 300 seconds.

<Example 3>
Under the same conditions as in Example 1, 300 nm of SiO ₂ was deposited on the N face side of the GaN wafer, and H ⁺ ions were implanted at 4.3 × 10 ¹⁷ atoms / cm ² from the SiO ₂ film face side. The substrate after ion implantation was convex when the ion implantation surface was on the upper side, and Warp was 260 μm. Subsequently, CMP was performed on the surface of the SiO ₂ film on the GaN wafer, and the surface roughness RMS was adjusted to be 0.2 nm so that the surface could be bonded.
A sapphire wafer having a GaN thin film transferred thereon was obtained in the same manner as in Example 1 except that a sapphire wafer was used as the support substrate and the pressurization time was 120 seconds in the subsequent steps.

<Example 4>
A silicon wafer having a GaN thin film transferred thereon was obtained in the same manner as in Example 1 except that a silicon wafer was used as the support substrate.

<Example 5>
Under the same conditions as in Example 1, 300 nm of SiN was deposited on the N face side of the GaN wafer, and H ⁺ ions were implanted at 4.3 × 10 ¹⁷ atoms / cm ² from the SiN film face side. The substrate shape after ion implantation was convex when the ion implantation surface side was the upper side, and Warp was 50 μm. Subsequently, CMP was performed on the surface of the SiN film on the GaN wafer, and the surface roughness RMS was adjusted to be 0.2 nm so that the surface could be bonded.
A sapphire wafer was used as a support substrate, and the subsequent steps were performed in the same manner as in Example 1 to obtain a sapphire wafer to which a GaN thin film was transferred.

<Comparative Example 1>
A sapphire wafer to which a GaN thin film was transferred was obtained in the same manner as in Example 1 except that bonding was performed by pressing the outer peripheral portion with a pin in an unpressurized state at the time of bonding.

<Comparative example 2>
A sapphire wafer to which a GaN thin film was transferred was obtained in the same manner as in Example 1 except that the surface activation treatment was not performed before pressurization.

<Comparative Example 3>
Bonding was performed in the same manner as in Example 1 except that the bonded body was obtained by holding the GaN wafer and the sapphire wafer for 60 seconds at a pressure of 7.0 MPa. When the obtained joined body was taken out, a crack was generated in the sapphire substrate.

<Comparative example 4>
Under the same conditions as in Example 1, 300 nm of SiO ₂ was deposited on the N face side of the GaN wafer, and H ⁺ ions were implanted at 5.0 × 10 ¹⁷ atoms / cm ² from the SiO ₂ film face side. The substrate shape after ion implantation was convex when the ion implantation surface was on the upper side, and Warp was 350 μm. Subsequently, CMP was performed on the surface of the SiO ₂ film on the GaN wafer, and the surface roughness RMS was adjusted to be 0.2 nm so that the surface could be bonded.
The steps from the sapphire as the support substrate to the subsequent surface activation treatment, bonding by pressurization and heat treatment were performed under the same conditions as in Example 1. When the state of the bonded body after the heat treatment was observed, it was transferred only in the vicinity of the center and not transferred to the outer peripheral portion.

 Table 1 shows the bonding conditions and transfer results of Examples 1 to 5 and Comparative Examples 1 to 4.

When Example 1 is compared with Comparative Examples 1 and 2, the transfer of the GaN thin film is not successful without either the surface activation treatment or the predetermined pressure treatment, and the entire wafer surface is not obtained until both treatments are used. Can now be transferred. In Comparative Example 3, the wafer was damaged because the pressure during pressurization was too high. That is, the pressure has an upper limit, which is about 5.0 MPa. Further, in Examples 1 and 3 and Comparative Example 4, the Warp of the GaN wafer was different, and when Warp became too large, a region where no transfer occurred even when the pressure was increased was generated. For this reason, it is necessary to control the conditions so that Warp is 300 μm or less.
The scope of claims at the beginning of the filing of the present application is as follows.
[Claim 1] A step of obtaining a nitride semiconductor substrate having an ion-implanted layer therein by implanting ions from the surface, wherein the nitride semiconductor substrate is convex when the ion-implanted surface is on the upper side. A step having a warped shape with a warp of 10-300 μm;
Performing a surface activation process on at least one of the ion-implanted surface of the nitride semiconductor substrate and the surface of a support substrate to be bonded to the nitride semiconductor substrate;
A step of facing and superimposing the ion-implanted surface of the nitride semiconductor substrate and the surface of the support substrate, and bonding them under a pressure of 0.5 to 5.0 MPa;
Peeling the nitride semiconductor substrate along the ion implantation layer, and transferring the nitride semiconductor thin film onto the support substrate;
A method of manufacturing a composite substrate including at least a nitride semiconductor thin film on a support substrate.
[Claim 2] In the bonding step, heat treatment is performed at 100 to 300 ° C. while bonding under the pressure, or the nitride semiconductor thin film is transferred onto the supporting substrate after the bonding step. The manufacturing method of Claim 1 including the process of heat-processing the said bonded board | substrate at 100-300 degreeC before the process to perform.
[Claim 3] The manufacturing method according to claim 1 or 2, wherein the pressure in the bonding step is maintained for 1 to 600 seconds.
[Claim 4] Before the step of implanting the ions into the nitride semiconductor substrate, SiO ₂ , Si ₃ N ₄ and SiO _x N _y (0 <x) are formed on the surface of the nitride semiconductor substrate into which the ions are implanted. The manufacturing method as described in any one of Claims 1-3 including the process of forming the film | membrane selected from <2, 0 <y <1.3).
[Claim 5] The manufacturing method according to any one of claims 1 to 4, wherein a surface roughness RMS of each bonding surface of the nitride semiconductor substrate and the supporting substrate in the bonding step is 1 nm or less. .
[6] The manufacturing method according to any one of [1] to [5], wherein the nitride semiconductor substrate is a GaN substrate or an AlN substrate.
[7] The method according to any one of [1] to [6], wherein the support substrate is selected from the group consisting of silicon, sapphire, alumina, SiC, AlN, SiN, and diamond.

DESCRIPTION OF SYMBOLS 1 GaN wafer 1a GaN thin film 1b GaN wafer 2 after peeling 2 SiO ₂ film 2a Ion-implanted surface 3 Ion 4 Ion-implanted layer 5 Sapphire substrate (support substrate)
5a Bonding surface 6 Ion beam 7 Pressure 8 Bonded substrate 9 Composite substrate

Claims (7)

A process for obtaining a nitride semiconductor substrate having an ion implantation layer from the surface to the inside by implanting ions, 10 [mu] m or more warped in a convex shape when the nitride semiconductor substrate has an upper said ion-implanted surface a step of 300μm Ri shape der having the warp, represents a warpage in the unclamped state where the warp is evaluated by MF1390 of SEMI standards in,
Performing a surface activation process on at least one of the ion-implanted surface of the nitride semiconductor substrate and the surface of a support substrate to be bonded to the nitride semiconductor substrate;
A step of facing and superimposing the ion-implanted surface of the nitride semiconductor substrate and the surface of the support substrate, and bonding them under a pressure of 1.0 MPa or more and 4.0 MPa or less ;
A method for producing a composite substrate comprising a nitride semiconductor thin film on a support substrate, comprising at least a step of peeling the nitride semiconductor substrate along the ion implantation layer and transferring the nitride semiconductor thin film onto the support substrate. Wherein either heat treatment bonding while at 100 ° C. or higher 300 ° C. or less under a pressure in the step of the bonding, or a step of transferring the nitride semiconductor thin film on the supporting substrate even after the be bonded step before The manufacturing method according to claim 1, further comprising a step of heat-treating the bonded substrates at 100 ° C. or more and 300 ° C. or less . The manufacturing method according to claim 1 or 2, wherein the pressure in the bonding step is maintained for 1 second or more and 600 seconds or less . Before the step of injecting the ions into the nitride semiconductor substrate, forming a SiO _2, Si ₃ N ₄ and SiO _x N _y or we selected the film on the surface of implanting the ions of the nitride semiconductor substrate step only contains the formula, x and y are the production method according to any one of claims 1 to 3 satisfy respectively 0 <x <2,0 <y < 1.3. The manufacturing method according to claim 1, wherein a surface roughness RMS of each bonding surface of the nitride semiconductor substrate and the support substrate in the bonding step is 1 nm or less. The manufacturing method according to claim 1, wherein the nitride semiconductor substrate is a GaN substrate or an AlN substrate. It said support substrate is silicon, sapphire, alumina, SiC, method according to any one of claims 1 to 6 AlN, is selected from the group consisting of SiN and diamond.

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