JP5411438B2 - Manufacturing method of SOI substrate - Google Patents

Description

  The present invention relates to a method for manufacturing an SOI substrate, and more particularly to a method for manufacturing an SOI substrate in which the surface treatment method of a silicon thin film that has been thinned and transferred by ion implantation is improved.

Silicon on insulator (SOI) substrates have been widely used to reduce parasitic capacitance and increase device speed and power saving.
In recent years, there is an increasing demand for a thin film SOI having an SOI layer (silicon layer) of 100 nm or less in order to make a fully depleted layer type SOI device. This is because the device can be expected to increase in speed by reducing the thickness of the SOI layer.

As the SOI layer becomes thinner, the required in-plane film thickness uniformity is becoming stricter.
In general, a thin-film SOI substrate is pre-implanted with hydrogen ions into a donor wafer, and then bonded to a handle wafer, and the SOITEC method or SiGen method in which the thin film is transferred from the donor side to the handle side along the hydrogen ion implantation interface. At this time, an ion implantation defect layer (amorphous layer) of about 0.1 μm remains in the transferred silicon thin film, and surface roughness of several nm or more is introduced on the thin film surface by RMS. (See Non-Patent Document 1, for example).

Here, the SOITEC method is to bond both the donor and handle wafers at room temperature and then raise the temperature to around 500 ° C. to form holes called microcavities at the hydrogen injection interface and thermally exfoliate to transfer the thin film. It is a method to do.
On the other hand, the SiGen method is a surface plasma activation treatment as a pretreatment for bonding both the donor and handle wafers, bonding at room temperature, achieving high bonding strength at this point, and at low temperature (300 ° C. if necessary) This is a method of transferring the thin film by applying mechanical impact to the hydrogen ion implantation interface after performing the heat treatment before and after). Since this SiGen method can be a lower temperature process than the SOITEC method, it is a manufacturing method suitable for manufacturing bonding of wafers having different coefficients of thermal expansion (for example, Silicon on Quartz: SOQ).

Here, in the SOITEC method and the SiGen method, an ion implantation defect layer introduced by ion implantation exists on the surface portion of the separation surface. Several methods for removing the defective layer and smoothing the surface have been proposed.
One is a method of polishing about 0.1 μm, which is about the same thickness as the ion implantation defect layer, and removing the ion implantation defect layer. However, this method has a problem that it is difficult to achieve in-plane uniformity of the thickness of the remaining film due to polishing variations.
As another method, a method of recovering the crystallinity of the damaged layer by high-temperature heat treatment and then polishing by several tens of nanometers called touch polish in order to remove surface irregularities can be considered. At this time, there is also a report that the surface can be smoothed without using a touch polishing step by using hydrogen as the atmospheric gas (see, for example, Non-Patent Document 2).

However, since a high-temperature hydrogen heat treatment step is added, problems such as metal contamination, substrate warpage, an increase in manufacturing cost, and a decrease in throughput are newly generated. In addition, since hydrogen gas etches silicon, it has a drawback that it is difficult to achieve film thickness uniformity between substrates and within the substrate surface.
The problem is even more serious when the handle wafer is an SOI substrate made of a low-melting-point material other than silicon (quartz, glass, etc.) because high-temperature heat treatment cannot be applied.

B. Asper "Basic Mechanisms Involved in the Smart-Cut (R) process," Microelectronics Engineering, 36, p233 (1997) Nobuhiko Sato and Takao Yonehara "Hydrogen annealed silicon-on-insulator," Appl Phys Lett Vol 65, pp. 1924 (1994)

  The present invention has been made in view of the above problems, and efficiently removes an ion implantation defect layer existing in an ion implantation layer in the vicinity of a separation surface separated by an ion implantation separation method. It is an object of the present invention to provide a method for manufacturing an SOI substrate that can ensure a uniform film thickness and can also be applied to an SOI substrate using a low melting point material for a handle wafer.

In order to solve the above-described problems, the present invention provides a method for manufacturing an SOI substrate, in which a silicon wafer on which an ion-implanted layer is formed by implanting at least hydrogen ions, rare gas ions, or both is bonded to a handle wafer. A step of preparing a bonded substrate stack, a step of transferring the silicon wafer to the handle wafer by performing peeling along the ion implantation layer, and a pulsed state on the peeled surface of the transferred silicon wafer having a step of annealing by irradiating a laser that provides a method for manufacturing an SOI substrate according to claim.

In this way, the peeled surface of the transferred silicon wafer is annealed by irradiating a pulsed laser so that only the vicinity of the surface of the peeled surface can be instantaneously heated, and only the vicinity of the surface is melted. Can do. Since the melted surface is recrystallized using the silicon single crystal layer existing under the melted layer as a seed, the vicinity of the melted surface can be single crystallized, and a high-quality SOI substrate is obtained. Can do. Moreover, since the laser is irradiated onto the silicon wafer surface, the handle wafer can be kept at room temperature. For this reason, since it is not necessary to heat-process the whole bonded substrate at high temperature, it can suppress that problems, such as metal contamination and a curvature, generate | occur | produce. In addition, a low-melting-point material can be used for the handle wafer, and even with SOI substrates that are bonded together with wafers with different thermal expansion coefficients, it is possible to suppress the occurrence of bonding defects due to differences in the thermal expansion coefficients. can do.
Further, since recrystallization can be performed using the lower silicon single crystal layer as a seed, film thickness uniformity between the substrates and in the substrate surface can be easily ensured.
In addition, since the ion implantation defect layer can be removed by irradiating a pulsed laser, an SOI substrate manufacturing method that can be carried out very easily can be obtained.

Further, after the transferring step, before the step of irradiating the pulsed laser, a step of treating the peeled surface by a PACE method using plasma or a GCIB method using a gas cluster ion beam is performed. it is not preferable.
Thus, before the laser irradiation step, the ion-implanted defect layer on the separation surface is removed to some extent in advance by treating the peeled surface by the PACE method using plasma or the GCIB method using a gas cluster ion beam. . Since these PACE methods and GCIB methods are etching methods according to the in-plane film thickness variation, it is possible to improve the film thickness uniformity of the silicon wafer surface before laser annealing. The film thickness uniformity in the substrate surface can be further increased.

Further, the bonded substrate to be prepared is bonded after forming the ion implantation layer on the silicon wafer and then performing a plasma activation process on at least one bonded surface of the silicon wafer and the handle wafer. later, and that increase the bonding strength by a heat treatment of 350 ° C. or less, and a step of the transfer, it is not preferable that shall be peeled at the ion implanted layer by applying a mechanical impact to the ion implanted layer.
In this way, by using the so-called SiGen method as a method for preparing the bonded substrate, the bonding strength of the bonded substrate can be increased, so that occurrence of defective bonding can be suppressed. In addition, since it is not necessary to perform high-temperature heat treatment, it is suitable for bonding different kinds of substances, and it is possible to further suppress the occurrence of problems of metal contamination and warpage of the substrate.

Further, the bonded substrate to be prepared is formed by forming the ion-implanted layer on the silicon wafer, and then bonding the silicon wafer and the handle wafer, and the transferring step is performed by heat treatment at 500 ° C. or more. carried by it is not preferable that shall be peeled at the ion implanted layer.
Thus, by using the so-called SOITEC method as a method for preparing the bonded substrate, the silicon wafer to be transferred can be made thin, and the surface roughness of the peeled surface can be made low. it can.

Further, in the step of preparing the bonded substrate, the handle wafer, quartz, glass, sapphire, SiC, alumina, have preferably be comprised of any material of aluminum nitride.
As described above, since the insulating material described above is used for the handle wafer, it is possible to suppress leakage current from flowing into the SOI substrate as compared with the case where a silicon wafer is used as the handle wafer. Low power consumption.

Further, after the step of the transfer, before the step of irradiating the pulsed laser, the release surface, it is not preferable to perform the step of chemical etching.
In this way, by performing chemical etching on the release surface before the laser irradiation step, the ion implantation defect layer existing on the surface of the release surface can be removed to some extent in advance. For this reason, since the thickness of the layer to be melted can be reduced in the laser annealing step, the process time of the laser annealing step can be shortened. Moreover, since the output of the applied laser can be suppressed, the temperature rise of the silicon thin film can be further suppressed.

The chemical etching is preferably etching using at least one etching solution of KOH solution, NH ₄ OH solution, NaOH solution, CsOH solution, SC1 solution, EDP solution, TMAH solution, and hydrazine solution. Yes.
By using the above-mentioned etching solution as the chemical etching, it is possible to more reliably perform the etching of the peeling surface of the silicon wafer in the chemical etching step. Removal can be performed more reliably.

Further, after the step of the transfer, before the step of irradiating the pulsed laser, with respect to the peeling surface, Ru can have a step of performing CMP polishing or heat treatment.
As described above, by performing CMP polishing or heat treatment on the separation surface before the laser irradiation step, the ion implantation defect layer existing on the separation surface can be greatly reduced. Therefore, the process time of the laser annealing process can be further shortened.

  As described above, according to the method for manufacturing an SOI substrate of the present invention, only the vicinity of the surface of the peeling surface can be instantaneously heated to a high temperature, and only the vicinity of the surface can be melted and recrystallized. Can be single-crystallized. In addition, since the laser is irradiated on the surface of the silicon wafer, only the surface of the silicon wafer becomes hot, and the handle wafer can be kept at room temperature. For this reason, since it is not necessary to heat-process the whole bonded substrate at high temperature, it can suppress that problems, such as metal contamination and a curvature, generate | occur | produce. In particular, even when bonding between different substrates, peeling and cracking do not occur. Further, a low melting point material can be used as the handle wafer. Further, since recrystallization can be performed using the lower silicon single crystal layer as a seed, film thickness uniformity between the substrates and in the substrate surface can be easily ensured. In addition, since the ion implantation defect layer can be removed by irradiating a pulsed laser, an SOI substrate manufacturing method that can be carried out very easily can be obtained.

Hereinafter, the present invention will be described more specifically.
As described above, the ion implantation defect layer existing in the ion implantation layer in the vicinity of the separation surface separated by the ion implantation separation method can be efficiently removed, and the film thickness uniformity between the substrates and in the substrate surface can be ensured. In addition, development of a manufacturing method of an SOI substrate that can be applied to, for example, bonding between dissimilar substances or an SOI substrate using a low-melting-point material for a handle wafer has been awaited.

  Therefore, the present inventors can remove only the ion implantation defect layer in the vicinity of the peeling surface at a high temperature to melt and recrystallize the ion implantation defect layer and ensure film thickness uniformity. , Earnestly studied.

  As a result, the present inventors can melt and recrystallize only the ion-implanted defect layer in the vicinity of the peeling surface at a high temperature by irradiating the peeling surface with a pulsed laser, which can solve the above-mentioned problems And the present invention was completed.

Hereinafter, although the manufacturing method of the SOI substrate of this invention is demonstrated with reference to FIGS. 1-3, this invention is not limited to these.
FIG. 1 is a process diagram showing an example of a process of a method for manufacturing an SOI substrate according to the present invention. 2 and 3 are process diagrams showing another example of the process of the method for manufacturing an SOI substrate according to the present invention.

(Process a: Preparation of bonded substrate)
First, as shown in FIG. 1A, a bonded substrate on which a silicon wafer 11 on which an ion-implanted layer 14 is formed by implanting hydrogen ions, rare gas ions, or both, and a handle wafer 12 are bonded together. 13 is prepared.

Here, when the bonded substrate is prepared, the handle wafer can be made of any material of quartz, glass, sapphire, SiC, alumina, and aluminum nitride.
In the present invention, as will be described later, annealing by a pulse laser is used to remove the ion-implanted damage layer on the peeling surface of the silicon thin film surface. For this reason, only the vicinity of the silicon thin film surface is instantaneously heated ( Since the substrate remains at a low temperature, the substrate is not limited to silicon, and it is possible to use a different substance such as quartz or glass or a material having a low melting point.
Further, since the insulating material as described above can be used for the handle wafer, it is possible to suppress a leakage current from flowing through the SOI substrate as compared with the case where a silicon wafer is used as the handle wafer. This makes it possible to reduce the power consumption of the device.

(Process b: Peeling)
Next, as shown in FIG. 1B, peeling is performed along the ion implantation layer 14, the silicon wafer 11 of the bonded substrate 13 is thinned, and the silicon thin film is transferred to the handle wafer 12.

Here, the bonded substrate 13 to be prepared is bonded after forming the ion implantation layer 14 on the silicon wafer 11 and then performing plasma activation on at least one bonded surface of the silicon wafer 11 and the handle wafer 12. Thereafter, the bonding strength can be increased by a heat treatment at 350 ° C. or lower, and the peeling process can be performed along the ion implantation layer 14 by applying a mechanical impact to the ion implantation layer 14.
In this way, by using the so-called SiGen method as a method for preparing the bonded substrate, the bonding strength of the bonded substrate can be increased, so that occurrence of defective bonding can be suppressed. In addition, since it is not necessary to perform high-temperature bonding heat treatment or peeling heat treatment, it is possible to further suppress the occurrence of problems of metal contamination and warpage of the substrate. In particular, when bonding between different substances, cracking or peeling occurs due to the difference in thermal expansion coefficient when heat treatment is performed at high temperature, but there is no such concern with the SiGen method.

Further, the prepared bonded substrate 13 is formed by forming the ion implantation layer 14 on the silicon wafer 11, and then bonding the silicon wafer 11 and the handle wafer 12, and performing a heat treatment at 500 ° C. or higher. It can be peeled off by the ion implantation layer 14.
In this way, by using the so-called SOITEC method as a method for preparing a bonded substrate, it is possible to reduce the thickness of the silicon thin film to be transferred and to reduce the surface roughness of the peeling surface. it can.

(Process c: Laser irradiation)
Next, as illustrated in FIG. 1C, the SOI substrate 10 is obtained by irradiating the peeling surface 15 with a pulsed laser.
As the pulsed laser irradiated to the peeling surface 15, for example, an excimer laser which is an nsec order pulse oscillation laser such as XeCl or KrF can be used, but it is not limited to this.
In this process, the ion implantation defect layer of the ion implantation layer on the thin film surface is melted and recrystallized using the lower single crystal silicon layer as a seed, thereby simultaneously recovering the ion implantation damage near the surface and smoothing the surface. Is what you do. Further, by using a pulsed laser, only the vicinity of the surface can be instantaneously heated to a high temperature (˜1400 ° C.), and the handle substrate can be kept at a low temperature.

Here, in the laser irradiation process, the irradiation atmosphere is preferably an inert gas.
By using an inert gas as the atmospheric gas, etching of the bonded substrate in the laser annealing step can be minimized, so that the film thickness uniformity within the substrate surface can be further increased.

Next, a method for manufacturing the SOI substrate of the present invention illustrated in FIG. 2 will be described, but the present invention is not limited to the following examples.
(Process a ': Preparation of bonded substrate)
First, as shown in FIG. 2 (a ′), as in FIG. 1 (a), a silicon wafer 11 in which an ion implantation layer 14 is formed by implanting hydrogen ions, rare gas ions, or both, and a handle. A bonded substrate 13 on which the wafer 12 is bonded is prepared.

(Process b ': Peeling)
Next, as shown in FIG. 2 (b ′), as in FIG. 1 (b), peeling is performed along the ion implantation layer 14, and the silicon wafer 11 of the bonded substrate 13 is thinned to form a silicon thin film. Is transferred to the handle wafer 12.

(Step c ′: treatment by PACE method or GCIB method)
Next, as shown in FIG. 2 (c ′), the peeling surface 15 can be processed by a PACE method using plasma or a GCIB method using a gas cluster ion beam.
As described above, the PACE method and the GCIB method of etching according to the in-plane film thickness variation can improve the film thickness uniformity of the silicon thin film surface before the laser irradiation annealing process described later. Further, the film thickness uniformity within the substrate surface of the SOI substrate can be further increased.

Here, the PACE method is a method of making the wafer thickness (SOI layer thickness) uniform while locally etching the surface of the wafer with a plasma gas. After the measurement by the capacitance method, by controlling the etching removal amount by the plasma gas according to the thickness distribution, the wafer surface can be made highly flat.
In the GCIB method, a mass atomic group (gas cluster) of a gaseous substance is formed at normal temperature and normal pressure, and the gas cluster ions generated by bathing electrons are accelerated by an acceleration voltage and irradiated to the wafer surface. Similar to the PACE method, the wafer thickness distribution is measured by the optical interference method or the capacitance method, and then the etching removal amount by gas cluster ions is controlled according to the thickness distribution. The in-plane can be made highly flat.
Specific embodiments such as the PACE method and the GCIB method are not particularly limited, and known apparatuses and methods can be appropriately used.

(Process d ': Laser irradiation)
Thereafter, as shown in FIG. 2 (d ′), the SOI substrate 10 is obtained by irradiating the surface of the silicon thin film subjected to the processing by the PACE method or the GCIB method with a pulsed laser.

  The process of FIG. 2 differs from the process of FIG. 1 in the presence or absence of a process of performing a PACE method using plasma or a GCIB method using a gas cluster ion beam after the peeling process and before the laser irradiation process. Thereby, the laser irradiation process can be shortened and the film thickness distribution can be made more uniform.

Next, a method for manufacturing the SOI substrate of the present invention illustrated in FIG. 3 will be described, but the present invention is not limited to the following examples.
(Process a ″: Preparation of bonded substrate)
First, as shown in FIG. 3A ″, similarly to FIG. 1A, a silicon wafer 11 in which an ion implantation layer 14 is formed by implanting hydrogen ions, rare gas ions, or both, A bonded substrate 13 on which the handle wafer 12 is bonded is prepared.

(Process b '': peeling)
Next, as shown in FIG. 3 (b ″), similarly to FIG. 1 (b), peeling is performed along the ion implantation layer 14, and the silicon wafer 11 of the bonded substrate 13 is thinned to form silicon. The thin film is transferred to the handle wafer 12.

(Process c ″: Chemical etching)
Next, as shown in FIG. 3C ″, a chemical etching process is performed on the peeling surface 15.
In this way, by performing chemical etching on the release surface before the laser irradiation step, the ion implantation defect layer existing on the surface of the release surface can be removed to some extent in advance. For this reason, since the output of an applied laser can be suppressed, the temperature rise of a silicon wafer can be further suppressed.

In addition, this chemical etching step can be performed using at least one etching solution of KOH solution, NH ₄ OH solution, NaOH solution, CsOH solution, SC1 solution, EDP solution, TMAH solution, and hydrazine solution. .
As described above, since chemical etching is performed using the above-described etching solution, the peeling surface of the silicon wafer can be more reliably etched in the chemical etching step, so that ions existing on the surface of the peeling surface can be obtained. The implantation defect layer can be removed more reliably.

(Process d ″: treatment by PACE method or GCIB method)
Thereafter, as shown in FIG. 3 (d ″), the surface of the silicon thin film subjected to the chemical etching can be processed by the PACE method using plasma or the GCIB method using gas cluster ion beam. . This process can be performed in the same manner as in FIG.

(Process e '': Laser irradiation)
Thereafter, as shown in FIG. 3 (e ″), the SOI substrate 10 is obtained by irradiating the surface of the silicon thin film subjected to the processing by the PACE method or the GCIB method with a pulsed laser.

  The process of FIG. 3 differs from the process of FIGS. 1 and 2 in the presence or absence of a chemical etching process.

In the illustration of FIG. 3, the chemical etching is followed by the processing by the PACE method and the GCIB method. However, the present invention is not limited to this, and this order can be reversed.
2 and 3, the handle wafer can be made of any material of quartz, glass, sapphire, SiC, alumina, and aluminum nitride, and a method for preparing a bonded substrate is also available. Needless to say, the so-called SiGen method or the SOITEC method can be used.

Here, steps (b) and (c) in FIG. 1, steps (b ′) and (d ′) in FIG. 2, and steps (b ″) and (e ″) in FIG. Thereafter, CMP polishing or heat treatment can be performed on the surface of the silicon thin film before the laser irradiation step.
Thus, by performing CMP polishing or heat treatment on the surface of the silicon thin film after the peeling step and before the laser irradiation step, the number of ion implantation defect layers can be significantly reduced. This can reduce the time required for the annealing process.

  As described above, according to the method for manufacturing an SOI substrate of the present invention, only the ion-implanted damaged layer near the surface of the silicon thin film surface can be instantaneously heated to a high temperature. Therefore, only the vicinity of the ion-implanted damaged layer is melted / recrystallized. It can be made. Accordingly, the vicinity of the surface can be single-crystallized. In addition, since the handle wafer of the bonded substrate can be kept at a low temperature, problems such as metal contamination and warpage can be suppressed. Further, the present invention can also be applied to bonding between different kinds of materials and an SOI substrate using a low melting point material for a handle wafer. Since the lower silicon single crystal layer can be recrystallized as a seed, film thickness uniformity between the substrates and in the substrate surface can be easily ensured. Furthermore, since the film thickness uniformity and single crystallization on the surface of the silicon thin film can be achieved by an easy means, it is possible to increase the throughput and reduce the manufacturing cost.

Hereinafter, the manufacturing method of the SOI substrate of the present invention will be described more specifically with reference to examples and comparative examples.
Example 1
As described below, an SOI substrate was manufactured according to the method for manufacturing an SOI substrate as shown in FIG.

  A bonded substrate having a diameter of 200 mm was prepared by performing hydrogen ion implantation and transferring a silicon thin film to a quartz substrate. When 81 points in the plane of the bonded substrate were measured and evaluated by AFM, the average film thickness of the silicon thin film was 150 nm and the in-plane film thickness variation was 5.4 nm. The surface roughness was 5.5 nm by RMS.

The surface of the silicon thin film of such a bonded substrate was irradiated with a pulsed excimer laser to perform surface annealing. As the conditions for this excimer laser, crystallization conditions of an output of 200 W and 500 mJ / cm ² were used.

  When 81 points in the plane of the SOI substrate after laser irradiation were measured and evaluated by AFM, the average film thickness of the silicon thin film was a little over 149 nm, and the in-plane film thickness variation was 5.5 nm. Further, the surface roughness was within 0.5 nm or less by RMS. And when the cross section of this SOI substrate was observed with the transmission electron microscope, it turned out that the silicon thin film surface is single-crystallizing.

(Example 2)
As described below, an SOI substrate was manufactured according to the method for manufacturing an SOI substrate as shown in FIG.
First, a bonded substrate as shown in Example 1 was prepared.
After that, this bonded substrate is subjected to GCIB processing to correct the film thickness variation within the substrate surface, and then irradiated with an excimer laser in the same manner as in Example 1 to perform the same evaluation as in Example 1. It was.

In Example 2, the film thickness of the silicon thin film after the GCIB treatment was 80 nm, and the in-plane film thickness variation was 1.8 nm.
The average film thickness of the silicon thin film of the SOI substrate after laser irradiation was a little less than 80 nm, and the in-plane film thickness variation was 1.9 nm. The surface roughness was 0.5 nm by RMS. When the cross section was observed, it was found that the silicon thin film surface was single crystallized.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

It is process drawing which shows an example of the process of the manufacturing method of the SOI substrate of this invention. It is process drawing which shows another example of the process of the manufacturing method of the SOI substrate of this invention. It is process drawing which shows another example of the process of the manufacturing method of the SOI substrate of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... SOI substrate, 11 ... Silicon wafer, 12 ... Handle wafer, 13 ... Bonded substrate, 14 ... Ion implantation layer, 15 ... Release surface.

Claims (7)

A method for manufacturing an SOI substrate, comprising:
at least,
A step of preparing a bonded substrate in which a silicon wafer on which an ion-implanted layer is formed by implanting hydrogen ions or rare gas ions or both of them and a handle wafer are bonded together;
Step of transferring the silicon wafer to the handle wafer by performing peeling along the ion implantation layer,
The peeling surface, a step of treating by a GCIB method using a gas cluster ion beam,
And a step of annealing by irradiating the peeled surface of the transferred silicon wafer with a pulsed laser. The bonded substrate to be prepared is formed after the ion implantation layer is formed on the silicon wafer, and then the plasma activation process is performed on at least one bonded surface of the silicon wafer and the handle wafer. It is assumed that the bond strength is increased by heat treatment at 350 ° C. or lower,
2. The method for manufacturing an SOI substrate according to claim 1, wherein in the transferring step, mechanical impact is applied to the ion-implanted layer and the ion-implanted layer is peeled off. The bonded substrate to be prepared is formed by forming the ion implantation layer on the silicon wafer, and then bonding the silicon wafer and the handle wafer.
2. The method for manufacturing an SOI substrate according to claim 1, wherein the transferring step is performed by performing a heat treatment at 500 [deg.] C. or more to peel off the ion-implanted layer.   In the step of preparing the bonded substrate, the handle wafer is made of any material of quartz, glass, sapphire, SiC, alumina, and aluminum nitride. The manufacturing method of the SOI substrate as described.   5. The method according to claim 1, wherein after the transferring step and before the step of irradiating the pulsed laser, a step of chemically etching the peeled surface is performed. The manufacturing method of the SOI substrate as described. The chemical etching is etching using at least one etching solution of KOH solution, NH ₄ OH solution, NaOH solution, CsOH solution, SC1 solution, EDP solution, TMAH solution, and hydrazine solution. Item 6. A method for manufacturing an SOI substrate according to Item 5. 7. The method according to claim 1, further comprising a step of performing CMP polishing or heat treatment on the peeled surface after the transferring step and before the step of irradiating the pulsed laser. The manufacturing method of the SOI substrate of any one of Claims 1.

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