TWI482203B - And a method for producing a substrate having a single crystal thin film - Google Patents

Description

Method for manufacturing substrate having single crystal film

The present invention relates to a method for producing a substrate having a small number of crystal defects, particularly a single crystal film having substantially no crystal defects.

In the semiconductor devices such as power transistors, lasers, LEDs, and high-frequency devices, single crystal films or substrates such as ruthenium, SiC, GaN, AlN, zinc oxide, and diamond used in recent years have been highly integrated and brightened in the device. Under high frequency, etc., Yifa increases its importance.

A general single crystal thin film is laminated on a single crystal substrate having a lattice constant close to, for example, ruthenium, sapphire, SiC or the like by PVD method such as gas phase, liquid phase epitaxy or sputtering, EB, MBE, sublimation or the like. Grow and grow.

On the other hand, the substrate used in these is generally produced by growing a bulk crystal by a FZ method, a CZ method, a sublimation method or the like using seed crystal, and performing steps such as slicing and polishing.

However, the single crystal thin film or substrate obtained by the prior art is continuously present in the single crystal substrate used as the seed substrate, and is susceptible to crystal deformation due to the mismatch of the lattice constant and the thermal expansion coefficient. Or the disadvantage of laminating defects such as defects and microtubules.

When such crystal defects are often caused, the initial characteristics and long-term reliability of the device are adversely affected. Therefore, when manufacturing a high-performance and highly reliable semiconductor device, it is necessary to reduce crystal defects of the single crystal thin film or the substrate as much as possible.

Therefore, in order to reduce crystal defects in the past, as a single crystal substrate, a single crystal (Neat Perfect Crystal) having a crystal defect of about zero is used, and a single crystal substrate is laminated between a single crystal substrate and a single crystal film having a long length. Laminating several layers of a single crystal film having a lattice constant or a coefficient of thermal expansion between the two, such as SiO ₂ , germanium, GaN, AlGaN, InGaN, GaAs, etc., and laminating the target single crystal film (refer to the patent) Document 1).

However, the raw material cost or process cost of such improved technologies is high, economically unfavorable, and the reduction in safety and hygiene or crystal defects is not sufficient, and thus is not practical.

[Patent Document 1] JP-A-2004-048076

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a method for producing a single crystal layer, a single crystal film, and a single crystal, which can easily produce less crystal defects without using a special substrate, in particular It is a substrate of a single crystal film which does not substantially have a crystal defect, and by using the substrate as a seed substrate for epitaxial growth or bulk crystal growth, it is possible to produce a crystal defect with few defects, in particular, substantially no crystal defects. Crystalline layer, single crystal film and single crystal.

In order to achieve the above object, the present invention provides a method for fabricating a substrate having a single crystal film, characterized in that it comprises at least the following steps: preparing a donor substrate and processing the substrate A; and synthesizing a long single crystal layer on the donor substrate. Step B; injecting ions into a single crystal layer of the donor substrate formed with the single crystal layer to form an ion implantation layer; Step C of bonding the ion donor substrate to the processing substrate; And a step E of peeling off the ion implantation layer in the single crystal layer of the bonded donor substrate, thereby forming a single crystal thin film on the processing substrate; and using the processed substrate on which the single crystal thin film is formed as a donor The substrate is at least repeated in the above steps A to E (Patent No. 1 in the patent application).

According to the manufacturing method of the present invention described above, in the single crystal layer formed on the donor wafer, a portion having a small crystal defect which is less likely to affect the surface portion of the surface defect of the donor wafer is formed on the processed wafer as a single crystal. film. Further, by using the operation wafer for the next time as a donor wafer, a long single crystal layer is synthesized on a single crystal thin film having few crystal defects, and the formed single crystal layer becomes more crystalline defects than the former step. Less single crystal layer. By repeating the steps (A to E), a single crystal film formed on a donor wafer can be obtained as a single crystal film having reduced crystal defects and finally a substantially reduced number of homogeneous crystal defects and substantially close to zero. The substrate.

Moreover, according to the manufacturing method of the present invention, when a substrate having a single crystal thin film having few crystal defects is produced, it is not necessary to prepare a particularly expensive substrate, and no special steps are required, so that it can be manufactured inexpensively and easily. There are few crystal defects, especially substrates close to zero single crystal film.

At this time, the step E of the peeling may be performed by the heat treatment or the mechanical peeling on the ion implantation layer (the second item of the patent application).

When the peeling step is carried out by these methods, the flatness of the peeling surface can be improved.

The step C of injecting ions described above is to inject hydrogen ions or rare gas ions or both (application patent item 3).

In the production method of the present invention, the implanted ions may be appropriately selected from the above.

Further, it is preferred to smooth the surface of the single crystal layer of the donor substrate before the bonding step D (the fourth item of the patent application).

By smoothing the single crystal layer of the donor substrate before the bonding step, it is possible to suppress the occurrence of voids or the like at the bonding interface at the time of bonding, and it is possible to firmly bond them.

Further, after the peeling step E, it is preferred to smooth the surface of the single crystal film of the treated substrate (the fifth item of the patent application).

According to this, by smoothing the surface of the single crystal film of the processing substrate, a single crystal having less flatness and less crystal defects can be formed when the long single crystal layer is synthesized as a donor wafer on the surface of the single crystal film. Floor.

Further, the step B of synthesizing the long single crystal layer in the above layer can be carried out by any one of a CVD method, a PVD method, and a liquid phase epitaxial growth method (Patent Patent No. 6).

In the production method of the present invention, the method of laminating the single crystal layer may be appropriately selected from the above, and any of the methods may achieve a reduction in crystal defects of the single crystal layer having a long layer.

Further, the material of the donor substrate or the processing substrate may be any of ruthenium, sapphire, SiC, GaN, AlN, or zinc oxide (Japanese Patent Application No. 7).

In the manufacturing method of the present invention, the donor substrate or the processing substrate may be appropriately selected from the viewpoints of the purpose of fabricating the semiconductor device.

In addition, the processing substrate is preferably one of an amorphous substrate, a polycrystalline substrate, and a single crystal substrate having a surface roughness (Ra) of 0.5 nm or less (Application No. 8).

By using the substrate having the surface roughness and bonding them, it is possible to suppress the pores and the like and to firmly bond them.

Further, at least one of the donor substrate and the processing substrate prepared as described above may be a substrate having a buffer layer of any one of Sio ₂ , Si ₃ N ₄ , GaN, AlGaN, InGaN, AlN or a combination thereof (patent pending) Scope 9).

According to the substrate having the buffer layer, even if the material of the substrate and the single crystal layer are different, a single crystal layer having a good quality can be obtained, and the number of times of bonding and peeling can be reduced.

Further, the single crystal layer having a long synthesis layer may be any one of ruthenium, SiC, GaN, AlN, zinc oxide, and diamond (Application No. 10).

The single crystal layer which is synthesized by the method of the present invention can be appropriately selected from the above depending on the purpose of the semiconductor device to be fabricated, and can be used according to the present invention even in the case of a single crystal layer of a type which is prone to cause crystal defects. Invention to reduce crystal defects.

Further, before the bonding step D, at least one of the surface of the single crystal layer of the donor substrate and the surface of the processing substrate is preferably subjected to plasma treatment (Application No. 11).

As a result, the surface of the substrate subjected to the plasma treatment is activated by an increase in the OH group or the like, and when the substrate is adhered to the other substrate at the time of bonding, the substrate can be bonded more strongly by hydrogen bonding or the like.

Further, the present invention provides a method for producing a substrate having a single crystal layer, the method for producing a substrate having a single crystal layer characterized by at least a single crystal film of a substrate produced by the method for producing a substrate having a single crystal thin film of the present invention. , layer synthesis of long single crystal layer (application for the scope of the 12th item).

According to this, since the single crystal thin film of the substrate produced by the production method of the present invention has few crystal defects, if a long single crystal layer is laminated on the single crystal thin film, defects such as the influence of the surface of the substrate which is long in the layer formation can be prevented. The crystal defects are reduced, in particular, a single crystal layer having a desired thickness which can be almost zero defect.

At this time, the substrate in which the layer is formed into a long single crystal layer is preferably annealed (article 13 of the patent application).

When the annealing treatment is applied to the substrate having the single crystal layer obtained as described above, the surface of the single crystal layer can be smoothed, and the crystal defects can be further uniformly reduced.

Further, the present invention provides a method for producing an independent single crystal film, which is characterized in that at least a substrate having a single crystal layer produced by the method for producing a substrate having a single crystal layer of the present invention is implanted with ions. On the other hand, an ion implantation layer was formed in the single crystal layer, and the ion implantation layer was peeled off to obtain an independent single crystal film (Application No. 14 of the patent application).

According to this, if a portion of the single crystal layer of the substrate having the thick single crystal layer produced by the production method of the present invention is peeled off by a predetermined thickness by ion implantation, an independent single crystal having high flatness with almost no crystal defects can be produced. membrane.

At this time, the peeled single crystal film is preferably annealed (Patent No. 15 of the patent application).

By subjecting the obtained independent single crystal film to annealing treatment as described above, the surface of the single crystal film can be smoothed, and the crystal defects can be further uniformly reduced.

Further, the present invention provides a method for producing a single crystal, which is characterized in that at least a substrate having a single crystal film, a substrate having a single crystal layer, and a single crystal film are used, which are manufactured by the production method of the present invention. Either as a seed substrate for epitaxial growth or bulk crystal growth (Application No. 16 of the patent application).

The substrate having the single crystal thin film obtained by the production method of the present invention, the substrate having the single crystal layer, and the independent single crystal film may have few or no crystal defects, and therefore, if a substrate having the single crystal thin film is used, When a substrate having a single crystal layer and a separate single crystal film are used as a seed substrate, crystal defects derived from surface defects of the seed substrate hardly occur when epitaxial growth or bulk crystal growth occurs. Therefore, there is almost no crystal defect, and it can grow into a single crystal having a desired thickness.

As described above, according to the method for producing a single crystal thin film of the present invention, the upper portion of the single crystal layer having less crystal defects formed on the substrate can be used only as a single crystal thin film, and the long single layer can be further synthesized on the single crystal thin film of the substrate. The crystal layer can thus be a single crystal layer with less crystal defects. Thus, repeating the steps of the present invention can reduce the crystal defects of the layer-synthesized single crystal layer, and finally, a substrate having a single crystal thin film having extremely low defects, particularly substantially no crystal defects, can be produced. Further, when the substrate thus obtained is used as a seed substrate, crystal defects such as epitaxial growth or bulk crystal growth can be prevented from occurring at all.

When a single crystal thin film or a single crystal substrate is produced, the index defect of the substrate as the seed substrate is continuously used, and there is a problem that a so-called crystal defect occurs in the produced single crystal thin film or the like.

As a result of active research on these problems, the present inventors have found out that the crystal defects in the production of a single crystal thin film occur mostly in the synthesis of the first half of the single crystal substrate in the first half of the growth. The growth of the laminate is relatively small.

From this fact, a long single crystal layer is formed on the donor substrate, and an ion implantation layer is formed in the single crystal layer, and the crystal defect in the single crystal layer can be less than the upper layer (the latter half growth portion) after bonding with the processing substrate. ) is separated from the lower layer (the first half of the growth) and peeled off. Therefore, it has been found that a single crystal thin film having few crystal defects is formed on the processing substrate, and the substrate is used as a donor substrate. Repeating the above steps can reduce crystal defects of the single crystal thin film, and finally, crystal defects are extremely small, and in particular, almost A single crystal film of zero, thus completing the present invention.

Hereinafter, the substrate having the single crystal thin film, the substrate having the single crystal layer, and the method for producing the independent single crystal film of the present invention will be described in detail with reference to FIGS. 1 and 2 which are examples of the embodiment, but the present invention is not These restrictions.

1 is a flow chart showing an example of a manufacturing step of a substrate having a single crystal thin film of the present invention, and FIG. 2 is a view showing a substrate having a single crystal thin film obtained by the production method of the present invention, and having a single crystal layer. A flow chart of an example of a step of a substrate and a separate single crystal film.

First, in the step (A) of FIG. 1, the donor substrate 11 and the processing substrate 12 are prepared.

The material of the donor substrate 11 or the processing substrate 12 may be any of ruthenium, sapphire, SiC, GaN, AlN, or zinc oxide. The present invention can be suitably selected from the above depending on the purpose of the fabricated semiconductor device.

Further, it is preferable that at least one of the donor substrate 11 and the handle substrate 12 has any one of SiO ₂ , Si ₃ N ₄ , GaN, AlGaN, InGaN, and AlN, or the like, depending on the single crystal type in which the layer is synthesized. A substrate of a combined buffer layer. If a lattice constant or an expansion coefficient which is intermediate between the single crystal layer having a close-layer synthesis length and the donor substrate is appropriately selected as the buffer layer, a single crystal layer having a longer quality can be synthesized.

Moreover, it is preferable that the processed substrate 12 prepared at this time is any one of an amorphous substrate, a polycrystalline substrate, and a single crystal substrate having a surface roughness (Ra) of 0.5 nm or less. According to this, when the substrate having a surface roughness (Ra) of 0.5 nm or less is used, the pores at the bonding interface can be suppressed at the time of bonding, and a stronger bonding can be achieved. Further, since the prepared substrate is not caused to vaporize the single crystal layer, it is not necessary to be a single crystal, and a more expensive multi-crystal substrate or amorphous material may be used.

The following step (B) is a step of synthesizing the long single crystal layer 13 on the donor substrate 11.

At this time, the layer formation length can be carried out by any one of a CVD (Chemical Vapor Deposition) method, a PVD (Physical Vapor Deposition) method, and a liquid phase epitaxial growth method. The type of the single crystal layer which can be synthesized according to the layer is appropriately selected from the above.

Further, the single crystal layer 13 having a long layer composition may be any of ruthenium, SiC, GaN, AlN, zinc oxide, or diamond. The type of the single crystal layer can be appropriately selected from the above depending on the purpose of the semiconductor device to be fabricated, and the crystal defects can be reduced by the present invention even in the case of a single crystal layer of a type in which crystal defects are easily generated.

The step (C) is to implant ions into the single crystal layer 13 formed on the donor substrate 11 to form the ion implantation layer 14.

Hydrogen ions or rare gas ions or both are implanted into the single crystal layer 13, and the ion implantation layer (microbubble layer) 14 parallel to the surface is formed at an average depth of penetration of the ions, and the implantation temperature is preferably 25 ° C. 450 ° C. At this time, in the present invention, when the ion implantation layer 14 is formed, since it is formed in the single crystal layer 13, the layer portion (the latter half growth portion) having less crystal defects is transferred to the treated substrate after peeling after the peeling. Become a single crystal film. The ion implantation depth is adjusted in such a manner that the thickness of the film after peeling becomes a desired thickness.

In the step (D), the donor substrate 11 on which the ion implantation layer is formed is bonded to the processing substrate 12.

Before the bonding step (D), it is preferred to plasma-treat at least one of the surface of the single crystal layer 13 of the donor substrate 11 and the surface of the processing substrate. In the case of plasma treatment, for example, the substrate 12 to be cleaned by RCA cleaning or the like is placed in a vacuum chamber, and the plasma gas is introduced, and then about 5 to 10 seconds in a high-frequency plasma of about 100 W to make the surface Treated by plasma. As the gas for the plasma, hydrogen gas, argon gas, nitrogen gas or a mixed gas thereof or the like can be used.

Moreover, after lamination, the bonded substrate can be heated, and the bonding can be made stronger by heating. In the case of plasma treatment, it can be firmly bonded under heating at a relatively low temperature.

Further, before the step (D), the surface of the single crystal layer 13 of the donor substrate 11 is preferably smoothed. If it is a smooth surface, it can reduce the generation of pores at the bonding interface, and can be firmly bonded. The smoothing method can smooth the surface of the single crystal layer by applying, for example, grinding or annealing treatment.

Next, in step (E), by peeling off as the boundary ion implantation layer 14, the processed substrate 12 forming the single crystal thin film 15 can be obtained. The stripping method is to apply a heat treatment at a temperature of about 500 ° C or higher under an inert gas atmosphere, and to separate the ion-implanted layer by crystal rearrangement and agglomeration of bubbles. Further, the peeling method can also be peeled off by, for example, applying a mechanical external force.

Thus, by performing the peeling step by heat treatment using ion implantation or mechanically, a substrate having a flat peeling surface can be obtained.

The single crystal film 15 of the substrate 12 obtained in the steps (A) to (E) is transferred onto the processing substrate 12 by the upper portion (the latter half growth portion) of the single crystal layer 13 formed on the donor substrate 11. As a result, the crystal defects are less. In the present invention, the processed substrate 12 having the single crystal thin film 15 having a small crystal defect thus produced is used as the subsequent donor substrate, and the above steps (A) to (E) are repeated. According to this, by forming a long single crystal layer on the single crystal thin film having a reduced crystal defect, a single crystal layer having a reduced crystal defect can be further synthesized, and by repeating the steps, the crystal defect of the single crystal thin film is extremely small. Finally, a substrate having a single crystal film having substantially no crystal defects can be produced.

At this time, after the peeling step (E), the surface of the single crystal thin film 15 of the substrate 12 is preferably smoothed. Thereby, it is possible to more effectively reduce the crystal defects of the single crystal layer which is subsequently synthesized as the donor substrate.

Further, as shown in Figs. 2(f) to (g), the present invention can be applied to the upper layer of the substrate 12 of the single crystal thin film 15 having the desired crystal defect density obtained by repeating the steps of Figs. 1(A) to (E). A long single crystal layer 16 is synthesized. The long single crystal layer is synthesized in the upper layer of the single crystal thin film having almost no crystal defects produced by the production method of the present invention, and a favorable single crystal layer having no translocation defects can be formed. At this time, the substrate 12 having the single crystal layer 16 to be produced is preferably annealed, whereby the surface of the single crystal layer 16 is smoothed, and the single crystal layer 16 can be further more uniformly reduced in crystal defects.

Further, as shown in Figs. 2(g) to (i), the single crystal layer 16 formed on the substrate 12 having the single crystal thin film 15 produced by the production method of the present invention has a sufficient thickness, so that the single crystal layer is present in the single crystal layer. The ion implantation layer 14 is formed in 16 and peeled off, whereby a separate single crystal film 17 can be produced. The thus-formed independent single crystal film 17 can be made to have almost no crystal defects and high flatness. Further, by subjecting the produced single crystal film 17 to annealing, the surface of the single crystal film can be smoothed, and the crystal defects can be further reduced homogeneously.

Further, any of a substrate having a single crystal thin film, a substrate having a single crystal layer, and a single single crystal film produced by the production method of the present invention can be used as a seed substrate for epitaxial growth or bulk crystal growth.

The single crystal thin film, the single crystal layer, and the independent single crystal film obtained by the production method of the present invention have almost no crystal defects, and therefore, the substrate having the single crystal thin film, the substrate having the single crystal layer, and the independent single crystal are used. When the film is used as a seed substrate, crystal defects derived from defects on the surface of the seed substrate hardly occur when epitaxial growth or bulk crystal growth, and thus a single crystal having almost no crystal defects can be grown.

As described above, according to the method for producing a single crystal thin film of the present invention, only a layer of a single crystal layer having a small crystal defect formed on the substrate can be formed as a single crystal thin film, and further layered on the substrate. The single crystal layer can be a single crystal layer with less crystal defects. By repeating the steps of the present invention in this way, the crystal defects of the single crystal layer can be reduced, and finally, a substrate having a crystal defect of few, particularly a single crystal film having substantially no crystal defects, can be obtained. Further, when the substrate thus obtained is used as a seed substrate, a single crystal layer, a single crystal film, or a single crystal having almost no crystal defects can be obtained.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited thereto.

(Example 1)

A substrate having a diamond film is fabricated by the steps of FIG.

In the step (A) of Fig. 1, a single crystal substrate having a diameter of 6 inches (150 mm) is prepared as the donor substrate 11 and the processing substrate 12. At this time, the prepared substrate 12 is a surface roughness (Ra) of 0.3 nm.

In the step (B) of FIG. 1, the donor substrate 11 is placed in a 2.45 GHz microwave plasma apparatus, and hydrogen gas of 2% methane concentration is passed while being at 30 Torr (4000 Pa) and 850 ° C. Plasma CVD is performed to synthesize a diamond layer 13 having a thickness of 15 μm.

In the step (C) of FIG. 1, ion implantation is performed on the layer-forming long diamond layer 13 on the donor substrate 11 by an ion implanter at a hydrogen input amount of 5× ^{10 17} /cm ² to form an ion implantation layer 14 . .

In the step (D) of Fig. 1, the donor substrate 11 and the processing substrate 12 are adhered to each other, and are adhered to each other by heating with an infrared lamp to 250 °C.

In the step (E) of Fig. 1, the bonded substrate is heat-treated at 600 ° C and then peeled off from the hydrogen ion implantation layer to produce a tantalum single crystal substrate 12 having a diamond film 15 having a thickness of 500 nm.

Next, using the thus produced single crystal substrate 12 having the diamond film 15 as the next donor substrate, the above steps (A) to (E) were repeated three times to obtain a substrate having a diamond film having substantially zero crystal defects.

Subsequently, in steps (f) to (g) of FIG. 2, a 16 μm thick diamond layer is synthesized on the diamond film 15 of the substrate 12 in the same manner as in the step (B) of the embodiment 1, and annealed. Treatment (1200 ° C, 3 hours). The tantalum substrate having the diamond layer thus obtained is a substrate suitable for a high withstand voltage power transistor.

(Example 2)

In the step (A) of Fig. 1, a synthetic quartz substrate having a diameter of 4 inches (100 mm) was prepared as a donor substrate 11, and an AlN buffer layer having a thickness of 1 μm was laminated on the substrate by reactive sputtering. A sapphire substrate having a diameter of 4 inches (100 mm) was prepared as the processing substrate 12. At this time, the surface roughness (Ra) of the prepared substrate 12 was 0.38 nm.

In the step (B) of FIG. 1, ammonia and chlorine are used as a carrier gas on the surface of the buffer layer of the donor substrate 11 by a HVPE (hydride vapor phase epitaxy) method at 1050 ° C under normal pressure. The gallium layer is synthesized into a GaN single crystal layer 13 grown to a thickness of 8 μm.

In the step (C) of Fig. 1, ion implantation at a depth of 800 nm is performed on the upper GaN single crystal layer 13 synthesized on the donor substrate 11 by an ion implanter at a hydrogen input amount of 9 x ^{10 16} /cm ² to form an ion implantation layer 14 . .

In the step (D) of FIG. 1, the surface of the GaN single crystal layer 13 of the donor substrate 11 and the surface of the handle substrate 12 are subjected to plasma treatment in advance using a plasma gas (Ar/N ₂ ), followed by adhesion to heat. The heater is heated to 180 ° C for a strong fit.

In the step (E) of Fig. 1, a sapphire substrate 12 having a GaN single crystal thin film 15 having a thickness of 800 nm was produced by using a squeegee and a vacuum chuck to peel off the bonded substrate on the hydrogen ion implantation layer.

At this time, the translocation density of the GaN single crystal thin film 15 on the peeled sapphire substrate 12 (treated substrate) is ² ×10 ⁴ /cm ² , and the translocation density of the GaN single crystal thin film on the synthetic quartz substrate 11 (donor substrate) It is 8x10 ⁸ /cm ² . The single crystal film 15 in the layer portion above the single crystal layer 13 before peeling has a lower index density than the lower layer portion.

Using the thus produced sapphire substrate 12 having the GaN single crystal thin film 15 as a subsequent donor substrate, the above steps (A) to (E) are repeated four times to obtain a substrate having a GaN single crystal thin film having a substantially zero translocation density. .

Subsequently, in steps (f) to (g) of FIG. 2, a 7 μm thick GaN single crystal layer 16 is synthesized on the GaN single crystal thin film 15 of the substrate 12 in the same manner as in the step (B) of the embodiment 2. A sapphire substrate 12 having a GaN single crystal layer 16 having an indexing density of almost zero is obtained.

Further, in steps (g) to (i) of FIG. 2, in the same manner as in the step (C) of the second embodiment, ion implantation of a depth of 2000 nm on the GaN single crystal layer 16 of the manufactured sapphire substrate 12 forms ions. The layer 14 is injected. Subsequently, in the same manner as in the step (E), the ion implantation layer 14 was peeled off to produce a 2000 nm thick independent single crystal film 17 of only GaN single crystal. The independent single crystal film 17 thus obtained has no crystal defects or lifts at all, and is most suitable as a substrate for blue lasers.

Using the thus obtained GaN 2000 nm thick independent single crystal film 17 as a seed substrate, 0.3 g of 6N metal gallium was fed into an autoclave together with 10 g of 5N sodium azide and 40 g of 5N ammonia, and crystallized at 500 ° C. 10 days. As a result, a single crystal of GaN bulk of about 1 mm having almost no crystal defects was grown. When a HEMT (High Electron Mobility Transistor) is produced from a substrate cut out from a single crystal of the GaN bulk, it is extremely excellent in high frequency characteristics.

As described above, according to the production method of the present invention, the crystal defects of the single crystal thin film can be surely reduced, and a single crystal thin film having a final crystal defect of almost zero can be obtained. Further, the substrate having the thus obtained single crystal thin film is the most suitable substrate for use as a seed substrate for epitaxial growth or bulk crystal growth.

Further, the present invention is not limited to the above embodiment. The above-described embodiments are merely illustrative, and those having substantially the same technical concept as the technical concept described in the claims of the present invention can achieve the same effects and are included in the technical scope of the present invention.

11. . . Donor substrate

12. . . Processing substrate

13,16. . . Single crystal layer

14. . . Ion implantation layer

15. . . Single crystal film

17. . . Single crystal film

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing an example of a substrate manufacturing step of a single crystal film of the present invention.

Fig. 2 is a flow chart showing an example of a manufacturing process of a substrate having a single crystal layer and a single crystal film of the present invention.

11. . . Donor substrate

12. . . Processing substrate

13. . . Single crystal layer

14. . . Ion implantation layer

15. . . Single crystal film

Claims (16)

A method for manufacturing a substrate having a single crystal film, comprising the steps of: preparing a donor substrate and processing a substrate A; and forming a long single crystal layer on the donor substrate; and forming the single sheet a step C of implanting ions into a single crystal layer of the donor substrate of the crystal layer to form an ion implantation layer; a step D of bonding the ion-implanted donor substrate to the processing substrate; and the bonded donor substrate a step E of stripping the ion implantation layer in the single crystal layer; thereby forming a single crystal thin film on the processing substrate; and repeating the steps of A to E described above by using the processed substrate on which the single crystal thin film is formed as a donor substrate . The method for producing a substrate having a single crystal thin film according to the first aspect of the invention, wherein the peeling step E is performed by peeling off the ion implantation layer by heat treatment or mechanical means. A method of producing a substrate having a single crystal thin film according to claim 1 or 2, wherein the step C of implanting ions is implanted with hydrogen ions or rare gas ions or both. A method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein the surface of the single crystal layer of the donor substrate is smoothed before the bonding step D. A method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein the surface of the single crystal thin film of the treated substrate is smoothed after the peeling step E. The method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein the step B of synthesizing the long single crystal layer is performed by any one of a CVD method, a PVD method, and a liquid phase epitaxial growth method. get on. A method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein the material of the donor substrate or the processed substrate is any one of ruthenium, sapphire, SiC, GaN, AlN, or zinc oxide. The method for producing a substrate having a single crystal thin film according to the first or second aspect of the invention, wherein the processed substrate is an amorphous substrate, a polycrystalline substrate, or a single crystal substrate having a surface roughness (Ra) of 0.5 nm or less One. The method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein at least one of the prepared donor substrate and the processed substrate has SiO ₂ , Si ₃ N ₄ , GaN, AlGaN, InGaN, or the like. A substrate of a buffer layer of any one of AlN or a combination thereof. A method for producing a substrate having a single crystal thin film according to the first or second aspect of the invention, wherein the single crystal layer having a long synthesis layer is any one of ruthenium, SiC, GaN, AlN, zinc oxide, and diamond. A method for producing a substrate having a single crystal thin film according to claim 1 or 2, wherein at least one of a surface of the single crystal layer of the donor substrate and a surface of the processing substrate is electrically formed before the bonding step D Slurry treatment. A method for producing a substrate having a single crystal layer, characterized by at least a single crystal film of a substrate produced by the method for producing a substrate having a single crystal thin film according to any one of claims 1 to 11 A long single crystal layer is synthesized. The method for producing a substrate having a single crystal layer according to claim 12, wherein the substrate in which the layer is formed into a long single crystal layer is annealed. A method for producing an independent single crystal film, characterized in that at least a substrate having a single crystal layer manufactured by a method for producing a substrate having a single crystal layer of claim 12 or 13 is implanted with ions in the foregoing single crystal An ion implantation layer is formed in the layer, and the ion implantation layer is peeled off to thereby obtain an independent single crystal film. The method for producing an independent single crystal film according to claim 14, wherein the peeled single crystal film is annealed. A method for producing a single crystal, which is characterized in that at least a substrate having a single crystal film, a substrate having a single crystal layer, and a single crystal film are produced by using the manufacturing method according to any one of claims 1 to 15. Either as a seed substrate for epitaxial growth or bulk crystal growth.