Transfer method of semiconductor film layer

Abstract

According to the transfer method of the semiconductor thin film layer provided by the invention, the first porous layer with high porosity has relatively strong absorption capability on gas or liquid in the fluid medium, and the temporary bonding substrate is placed in a low-temperature environment; the first porous layer with high porosity is easier to crystallize than the second porous layer with low porosity, and due to the fact that after the fluid medium is crystallized, the volume of the fluid medium is increased, the first porous layer with high porosity bears stronger crystallization stress, and the mechanical strength of the first porous layer with high porosity is weak, the first porous layer with high porosity can bear stronger crystallization stress. Compared with a second porous layer, transverse cracking is easier to occur, so that transfer from the semiconductor film layer to the supporting substrate is realized, the transfer method has low requirements on a substrate material, relatively high universality is realized, the manufacturing cost can be reduced, and in addition, compared with an ion stripping method, the transfer method has the advantage that the production efficiency is improved. The thermal stress mismatch generated in the transfer process can be controlled in a lower range, so that high-quality transfer of the semiconductor film layer is realized.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor device manufacturing, and in particular to a method for transferring a semiconductor thin film layer. Background Art

[0002] In order to meet the needs of semiconductor device manufacturing technology, the following requirements generally need to be met during the transfer process of semiconductor films: 1) The transfer process does not significantly affect the quality of the semiconductor film and does not introduce high-density defects in the semiconductor film; 2) The transferred semiconductor film is not damaged, and the area of ​​successful transfer accounts for a large proportion (for example, >99%); 3) The thickness of the transferred semiconductor film is controllable and the thickness uniformity is good; 4) The film transfer process is simple, can be mass-produced, and the process cost is controllable.

[0003] In the existing semiconductor device preparation process, the method of first bonding and then partially removing the supply substrate is generally used. Among them, the methods of removing part of the supply substrate include: grinding and thinning method, ion stripping method and grinding and thinning combined with self-stop etching method. Among them, the grinding and thinning method can directly grind away the part of the supply substrate that needs to be removed, but this method is costly and has poor controllability of grinding thickness. It is not compatible with semiconductor processes with finer feature sizes, and it is more difficult to grind and remove when encountering semiconductor materials with higher hardness; the ion stripping method requires the injection of an appropriate amount of H, He and other types of ions into the supply substrate in advance, and then temperature annealing is performed after bonding to make the H and He ions gather into bubbles, thereby separating the supply substrate into two parts. Although this method has good thickness controllability, the required implanted ion concentration and stripping temperature of some materials are high, which results in high process cost, serious lattice damage, and serious thermal mismatch during stripping annealing, making it difficult to obtain high-quality semiconductor transfer films; the method of combining grinding thinning with self-stop etching can thin most of the supply substrate by grinding, so that the thinning process stops at other functional layers of the supply substrate, thereby achieving precise thinning of the supply substrate, but this method requires that the supply substrate must be a composite substrate and that there is a large selective etching ratio between different functional layers of the composite substrate, resulting in higher manufacturing costs.

[0004] Therefore, it is of great significance to develop a semiconductor thin film layer transfer method with greater universality, higher process reliability and lower process cost. Summary of the invention

[0005] In view of the shortcomings of the prior art mentioned above, the object of the present invention is to provide a method for transferring a semiconductor thin film layer, so as to solve the problems existing in the existing transfer technology, such as high manufacturing cost, poor controllability of grinding thickness, severe lattice damage, severe thermal mismatch during annealing, and difficulty in obtaining high-quality semiconductor transferred films.

[0006] To achieve the above-mentioned object and other related objects, the present invention provides a method for transferring a semiconductor thin film layer, the method for transferring a semiconductor thin film layer comprising the following steps:

[0007] Providing a transfer substrate, wherein the transfer substrate has a first surface and a second surface disposed opposite to each other, and forming a composite porous structure layer on the first surface of the transfer substrate;

[0008] Growing a semiconductor thin film layer on the surface of the composite porous structure layer;

[0009] Providing a supporting substrate, and performing a bonding process on the supporting substrate and the semiconductor thin film layer to form a temporary bonding substrate;

[0010] placing the temporary bonding substrate in a fluid medium so that the fluid medium enters into the composite porous structure layer;

[0011] The ambient temperature and / or ambient pressure of the temporary bonding substrate is changed so that the temporary bonding substrate is transversely cracked along the composite porous structure layer, thereby completing the transfer of the semiconductor thin film layer to the supporting substrate.

[0012] Optionally, the ambient temperature of the temporary bonding substrate is lowered to allow the fluid medium to crystallize in the composite porous structure layer, so that the temporary bonding substrate is transversely cracked along the composite porous structure layer.

[0013] Optionally, the ambient temperature and / or ambient pressure of the temporary bonding substrate is increased so that the fluid medium can diffuse into the composite porous structure layer more easily and quickly corrode the composite porous structure layer, causing the temporary bonding substrate to undergo lateral cracking along the composite porous structure layer.

[0014] Optionally, the composite porous structure layer includes a plurality of porous layers with different porosities.

[0015] Optionally, the composite porous structure layer includes a first porous layer and a second porous layer with different porosities, and the porosity of the first porous layer close to the first surface of the transfer substrate is greater than the porosity of the second porous layer away from the first surface of the transfer substrate.

[0016] Optionally, the method for forming the composite porous structure layer includes an electrochemical corrosion process, and after completing the electrochemical corrosion process, the composite porous structure layer needs to be oxidized to form an oxide film layer that completely covers or partially covers the surface of the micro-nano structure inside the composite porous structure layer.

[0017] Optionally, before growing the semiconductor thin film layer on the composite porous structure layer, the step also includes selectively removing the oxide film covering the composite porous structure layer at a depth of 5 nm to 1 μm extending downward from the surface of the composite porous structure layer, and annealing the transfer substrate in a hydrogen atmosphere or a mixed atmosphere of hydrogen and an inert gas, wherein the annealing temperature is 300 to 1400°C.

[0018] Optionally, before the support substrate is bonded to the semiconductor thin film layer, the method further includes forming a functional material layer on the first surface of the support substrate or on the semiconductor thin film layer.

[0019] Optionally, the functional material layer includes at least one of a single crystal semiconductor layer, a polycrystalline semiconductor layer, an amorphous material layer, an insulating dielectric layer, a piezoelectric material layer, a metal layer, and a compound conductive layer.

[0020] Optionally, before forming a temporary bonding substrate, a step of forming a patterned cavity structure is also included, wherein the patterned cavity structure can be completely located in the functional material layer in the depth direction, or span the interface between the functional material layer and the supporting substrate, or span the interface between the functional material layer and the semiconductor thin film layer, or be completely located in the supporting substrate and connected to the functional material layer.

[0021] Optionally, the fluid medium includes at least one of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., and the fluid medium can crystallize at a certain temperature.

[0022] Optionally, after placing the temporary bonding substrate in the fluid medium, the method further includes placing the temporary bonding substrate and the fluid medium in a sealed container, and performing pressurization and temperature raising steps.

[0023] Optionally, after the temporary bonding substrate is laterally cracked along the composite porous structure layer, the process further includes performing at least one of thinning, polishing, homoepitaxial growth or heteroepitaxial growth on the semiconductor thin film layer.

[0024] Optionally, the bonding process includes one of a hydrophilic bonding process, a thermal compression bonding process, a surface plasma activation bonding process or an anodic bonding process.

[0025] As described above, the semiconductor thin film layer transfer method of the present invention has the following beneficial effects: on the one hand, since the first porous layer with high porosity in the composite porous structure layer has a strong absorption capacity for gas or liquid in the fluid medium, by placing the temporarily bonded substrate in a low-temperature fluid medium environment, the first porous layer with high porosity is more likely to crystallize than the second porous layer with low porosity. Since the volume of the fluid medium increases when it crystallizes, the composite porous structure layer will be subjected to stronger crystallization stress. On the other hand, the first porous layer with high porosity has weaker mechanical strength, so it is more likely to undergo lateral cracking than the second porous layer with low porosity, thereby completing the transfer of the semiconductor thin film layer to the supporting substrate. The transfer method does not have high requirements on the substrate material, has strong universality, and can reduce manufacturing costs. In addition, compared with the ion stripping method, the thermal stress mismatch generated during the transfer process can be controlled within a lower range, thereby achieving high-quality transfer of the semiconductor thin film layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Shown is a process flow chart of the semiconductor thin film layer transfer method provided by the present invention.

[0027] Figures 2 to 9 Shown is a schematic cross-sectional structure diagram corresponding to each step in the semiconductor thin film layer transfer method provided by the present invention.

[0028] Component number description

[0029] 10. Transfer substrate; 101. First surface; 102. Second surface; 11. Composite porous structure layer; 110. First porous layer; 111. Second porous layer; 12. Semiconductor thin film layer; 13. Support substrate; 14. Functional material layer; 15. Cavity structure; 16. Temporary bonding substrate; 161. Front surface; 162. Back surface; 17. Fastening fixture; 18. Fluid medium; S1~S4: steps. DETAILED DESCRIPTION

[0030] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0031] For example, when describing the embodiments of the present invention in detail, for the sake of convenience, the schematic diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0032] For convenience of description, spatially relative terms such as "under", "below", "below", "below", "above", "on", etc. may be used herein to describe the relationship of one element or feature shown in the drawings to other elements or features. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0033] In the context of the present application, a structure in which a first feature is described as being "above" a second feature may include embodiments in which the first and second features are in direct contact, and may also include embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0034] It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and therefore the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0035] The present invention provides a method for transferring a semiconductor thin film layer 12, such as Figure 1 As shown, it is a process flow chart of the transfer method of the semiconductor thin film layer 12, which includes the following steps:

[0036] S1: providing a transfer substrate 10, wherein the transfer substrate 10 has a first surface 101 and a second surface 102 arranged opposite to each other, and forming a composite porous structure layer 11 on the first surface 101 of the transfer substrate 10;

[0037] S2: growing a semiconductor thin film layer 12 on the surface of the composite porous structure layer 11;

[0038] S3: providing a support substrate 13, and performing a bonding process on the support substrate 13 and the semiconductor thin film layer 12 to form a temporary bonding substrate 16;

[0039] S4: placing the temporary bonding substrate 16 in a fluid medium 18, so that the fluid medium 18 enters into the composite porous structure layer 11;

[0040] S5: changing the ambient temperature and / or ambient pressure of the temporary bonding substrate 16 so that the temporary bonding substrate 16 is transversely cracked along the composite porous structure layer 11 to complete the transfer of the semiconductor thin film layer 12 to the supporting substrate 13 .

[0041] The following is a further introduction to the transfer method of the semiconductor thin film layer 12 in conjunction with the accompanying drawings. It should be noted that the above sequence does not strictly represent the sequence of the transfer method of the semiconductor thin film layer 12 protected by the present invention, and those skilled in the art may change it according to the actual preparation steps. The following is a further introduction to the transfer method of the semiconductor thin film layer 12 in conjunction with the accompanying drawings, as follows:

[0042] In step S1, see Figure 1 and Figure 2 , providing a transfer substrate 10 , wherein the transfer substrate 10 has a first surface 101 and a second surface 102 that are oppositely disposed, and forming a composite porous structure layer 11 on the first surface 101 of the transfer substrate 10 .

[0043] As an example, Figure 2 As shown in a, the transfer substrate 10 has a first surface 101 and a second surface 102 arranged opposite to each other, wherein the material of the transfer substrate 10 can be a silicon-based material, such as a silicon wafer, silicon carbide or silicon oxide, and its shape can be circular, square or any other desired shape. In addition, the material of the transfer substrate 10 can also include any material of single crystal sapphire, aluminum nitride, gallium nitride, gallium arsenide, indium arsenide, indium phosphide and quartz, which is not particularly limited here. Before forming the composite porous structure layer 11 on the first surface 101 of the transfer substrate 1010, the transfer substrate 10 needs to be cleaned, and various liquids in the RCA cleaning process and common cleaning liquids such as deionized water, ethanol, acetone, isopropanol, etc. are used in the cleaning process.

[0044] In one embodiment, a composite porous structure layer 11 is formed on the first surface 101 of the transfer substrate 10 , and the composite porous structure layer 11 includes N porous layer structures, wherein N>2, and the porosity of each porous layer is different.

[0045] In another embodiment, if Figure 2 As shown in b, the composite porous structure layer 11 includes a first porous layer 110 and a second porous layer 111 with different porosities and stacked in sequence, wherein the porosity of the first porous layer 110 close to the first surface 101 of the transfer substrate 10 is greater than the porosity of the second porous layer 111. The second porous layer 111 is a low-porosity layer, and its lattice structure is relatively complete, thereby ensuring that the semiconductor thin film layer 12 grown by the subsequent epitaxial process has a higher quality. The first porous layer 110 is a high-porosity layer, and its thermal conductivity is lower and its mechanical strength is weaker. By lowering the ambient temperature of the temporary bonding substrate 16, the fluid medium 18 is more likely to crystallize in the first porous layer 110. Since the stress generated by the crystallization is more concentrated here, the first porous layer 110 is more likely to undergo lateral cracking.

[0046] As an example, the method for forming the composite porous structure layer 11 includes an electrochemical corrosion process, and after completing the electrochemical corrosion process, the composite porous structure layer 11 needs to be oxidized to form an oxide film layer that completely covers or partially covers the surface of the micro-nano structure inside the composite porous structure layer 11.

[0047] Specifically, an electrochemical corrosion process is used for the first surface 101 of the transfer substrate 10, and the corrosion depth of the porosity of the composite porous structure layer 11 is regulated by adjusting parameters such as the type of current signal, current intensity, solution composition ratio, lighting conditions, and corrosion time. After the electrochemical corrosion process is completed to form the composite porous structure layer 11, the composite porous structure layer 11 is also required to be subjected to an oxidation process to form an oxide film layer that completely covers or partially covers the surface of the micro-nano structure inside the composite porous structure layer 11, thereby enhancing the strength of the composite porous structure layer 11.

[0048] As an example, before growing the semiconductor thin film layer 12 on the composite porous structure layer 11, the steps also include selectively removing the oxide film covering the composite porous structure layer 11 and extending downward from the surface of the composite porous structure layer 11 to a depth of 5 nm to 1 μm, and annealing the transfer substrate 10 in a hydrogen atmosphere or a mixed atmosphere of hydrogen and an inert gas, wherein the annealing temperature ranges from 300 to 1400°C.

[0049] Before growing the semiconductor thin film layer 12 on the composite porous structure layer 11, it is also necessary to remove the oxide layer on the surface of the composite porous structure layer 11. Specifically, the oxide film layer covering the composite porous structure layer 11 is selectively removed by extending downward from the surface of the composite porous structure layer 11 to a depth of 5 nm to 1 μm. Then, the transfer substrate 10 and the composite porous structure layer 11 are annealed in a hydrogen atmosphere or a mixed atmosphere of hydrogen and an inert gas. The annealing temperature may be 300 to 1400°C, thereby further repairing the surface defects of the composite porous structure layer 11 and partially or completely healing the corrosion holes on the surface of the composite porous structure layer 11, which is more conducive to forming a high-quality semiconductor thin film layer 12.

[0050] In step S2, see Figure 1 and Figure 3 , a semiconductor thin film layer 12 is grown on the surface of the composite porous structure layer 11.

[0051] As an example, Figure 3As shown, epitaxial growth is performed on the surface of the composite porous structure layer 11 through an epitaxial process to obtain a semiconductor thin film layer 12 with a smooth surface. This embodiment does not specifically limit the process parameters of the semiconductor thin film layer 12, as long as a semiconductor thin film layer 12 with a smooth surface can be grown on the surface of the composite porous structure layer 11, the requirements can be met. It should be understood that those skilled in the art can achieve epitaxial growth of the semiconductor thin film layer 12 by controlling the epitaxial process conditions of the semiconductor thin film layer 12.

[0052] As an example, the material of the semiconductor thin film layer 12 can be the same as that of the transfer substrate 10, or different from that of the transfer substrate 10. The semiconductor thin film layer 12 can be a single-layer structure, or a multi-layer structure composed of different types of semiconductor film layers. Preferably, in this embodiment, the semiconductor thin film layer 12 is a multi-layer structure composed of different types of semiconductor film layers.

[0053] In step S3, see Figure 1 , Figures 4 to 6 , providing a supporting substrate 13, and performing a bonding process on the supporting substrate 13 and the semiconductor thin film layer 12 to form a temporary bonding substrate 16.

[0054] As an example, Figure 4 As shown, the support substrate 13 has a first surface and a second surface relative to each other, wherein the material of the support substrate 13 may be a silicon-based material, such as a silicon wafer, silicon carbide or silicon oxide, and its shape may be circular, square or any other desired shape. In addition, the material of the support substrate 13 may also include any one of single crystal sapphire, aluminum nitride, gallium nitride, gallium arsenide, indium arsenide, indium phosphide and quartz, which is not particularly limited here. The material selection of the support substrate 13 may be the same as that of the transfer substrate 10, or may be different from that of the transfer substrate 10. Preferably, in this embodiment, the material selection of the support substrate 13 is the same as that of the transfer substrate 10.

[0055] As an example, Figure 4 As shown, before the support substrate 13 is bonded to the semiconductor thin film layer 12 , the step of forming a functional material layer 14 on the first surface of the support substrate 13 or on the semiconductor thin film layer 12 is also included.

[0056] Specifically, the first surface of the support substrate 13 is bonded to the semiconductor thin film layer 12. Before bonding, a functional material layer 14 is epitaxially grown on the first surface of the support substrate 13 or on the semiconductor thin film layer 12 by an epitaxial process, so as to ensure the subsequent bonding quality of the support substrate 13 and the transfer substrate 10. The functional material layer 14 includes at least one of a single crystal semiconductor layer, a polycrystalline semiconductor layer, an amorphous material layer, an insulating dielectric layer, a piezoelectric material layer, a metal layer, and a compound conductive layer, that is, the functional material layer 14 can be composed of one of a single crystal semiconductor layer, a polycrystalline semiconductor layer, an amorphous material layer, an insulating dielectric layer, a piezoelectric material layer, a metal layer, and a compound conductive layer, or can be composed of multiple of a single crystal semiconductor layer, a polycrystalline semiconductor layer, an amorphous material layer, an insulating dielectric layer, a piezoelectric material layer, a metal layer, and a compound conductive layer, and there is no special limitation here.

[0057] In one embodiment, before forming the temporary bonding substrate 16, a step of forming a patterned cavity structure 15 is also included, wherein: Figure 5 As shown in a, the patterned cavity structure 15 can be completely located in the functional material layer 14 in the depth direction; or Figure 5 As shown in b, the patterned cavity structure 15 spans the interface between the functional material layer 14 and the supporting substrate 13; or as shown in Figure 5 As shown in FIG. 3 , the patterned cavity structure 15 spans the interface between the functional material layer 14 and the semiconductor thin film layer 12; or as shown in FIG. Figure 5 As shown in FIG. d, the patterned cavity structure 15 is completely located in the supporting substrate 13 and connected to the functional material layer 14. The arrangement of the patterned cavity structure 15 makes it easier to tape out the subsequently formed devices.

[0058] As Figure 6 As shown, after forming the functional material layer 14, the first surface of the support substrate 13 is bonded to the semiconductor thin film layer 12 to form a temporary bonding substrate 16, and the temporary bonding substrate 16 has a front side 161 and a back side 162 that are arranged opposite to each other. The bonding process includes one of a hydrophilic bonding process, a thermocompression bonding process, a surface plasma activation bonding process or an anodic bonding process. Preferably, in this embodiment, the bonding process is preferably a thermocompression bonding process.

[0059] In step S4, see Figure 1 and Figure 7 , placing the temporary bonding substrate 16 in a fluid medium 18 so that the fluid medium 18 enters into the composite porous structure layer 11 .

[0060] As an example, before the temporary bonding substrate 16 is transversely cracked along the composite porous structure layer 11 , a step of performing a high-temperature annealing and curing process on the temporary bonding substrate 16 is also included.

[0061] Specifically, after the first surface of the support substrate 13 is bonded to the semiconductor thin film layer 12 to form a temporary bonding substrate 16 , the temporary bonding substrate 16 is subjected to a high temperature annealing and curing process, thereby enhancing the bonding interface strength between the support substrate 13 and the semiconductor thin film layer 12 .

[0062] As an example, the fluid medium 18 includes at least one of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., and the fluid medium 18 can crystallize at a certain temperature.

[0063] Specifically, Figure 7 As shown, firstly, a fastening fixture 17 is used to clamp the front side 161 and the back side 162 of the temporary bonding substrate 16. The fastening fixture 17 can prevent the temporary bonding substrate 16 from warping to a certain extent, thereby avoiding the temporary bonding substrate 16 from producing irreversible deformation under a large stress, thereby improving the production yield; then, the temporary bonding substrate 16 is placed in a fluid medium 18, and the fluid medium 18 includes at least one of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., that is, The fluid medium 18 may include only one of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., or may include two or more of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., and then the temporary bonding substrate 16 and the fluid medium 18 are placed together in a closed container, and pressurized and heated, so as to reduce the surface tension of the fluid medium 18 and enhance the permeability of the fluid medium 18 in the composite porous structure layer 11.

[0064] In step S5, refer to Figure 1 and Figure 8 , changing the ambient temperature and / or ambient pressure of the temporary bonding substrate 16 so that the temporary bonding substrate 16 is laterally cracked along the composite porous structure layer 11, thereby completing the transfer of the semiconductor thin film layer 12 to the supporting substrate 13.

[0065] In one embodiment, the fluid medium 18 can crystallize at a certain temperature. By lowering the ambient temperature of the temporary bonding substrate 16, the fluid medium 18 can be crystallized in the composite porous structure layer 11. Since the volume of the fluid medium 18 increases during crystallization, the composite porous structure layer 11 will be subjected to strong crystallization stress. The first porous layer 110 in the composite porous structure layer 11 is a high-porosity layer with lower thermal conductivity and weaker mechanical strength. The stress generated by crystallization is more likely to accumulate in the first porous layer 110, making it easier for the temporary bonding substrate 16 to undergo lateral cracking along the first porous layer 110.

[0066] In another embodiment, the ambient temperature and / or ambient pressure of the temporary bonding substrate 16 can be increased so that the fluid medium 18 can diffuse into the composite porous structure layer 11 more easily and quickly corrode the composite porous structure layer 11, so that the temporary bonding substrate 16 is laterally cracked along the composite porous structure layer 11, thereby completing the transfer of the semiconductor thin film layer 12 to the supporting substrate 13.

[0067] As an example, after the temporary bonding substrate 16 is transversely cracked along the composite porous structure layer 11, the semiconductor thin film layer 12 is subjected to at least one of thinning, polishing, homoepitaxial growth or heteroepitaxial growth.

[0068] Specifically, Fig. 9 As shown, after the cleavage occurs between the transfer substrate 10 and the support substrate 13, the semiconductor film layer 12 on the surface of the support substrate 13 is thinned and polished to remove the residual second porous layer 111, and the semiconductor film layer 12 is thinned at the same time, so as to improve the surface flatness and roughness of the semiconductor film layer 12 and reduce the surface defects of the semiconductor film layer 12. In other embodiments, the semiconductor film layer 12 on the surface of the support substrate 13 can also be corroded, etched, annealed in a specific atmosphere, homoepitaxial or heteroepitaxial to achieve the removal of the second porous layer 111.

[0069] In summary, the present invention provides a method for transferring a semiconductor thin film layer. On the one hand, since the first porous layer with high porosity in the composite porous structure layer has a strong absorption capacity for gas or liquid in the fluid medium, by placing the temporarily bonded substrate in a low-temperature fluid medium environment, the first porous layer with high porosity is more likely to crystallize than the second porous layer with low porosity. Since the volume of the fluid medium increases when it crystallizes, the composite porous structure layer will be subjected to stronger crystallization stress. On the other hand, the first porous layer with high porosity has weaker mechanical strength, and therefore, it is more likely to undergo lateral cracking than the second porous layer with low porosity, thereby completing the transfer of the semiconductor thin film layer to the supporting substrate. The transfer method does not have high requirements on the substrate material, has strong universality, and can reduce manufacturing costs. In addition, compared with the ion stripping method, the thermal stress mismatch generated during the transfer process can be controlled within a lower range, thereby achieving high-quality transfer of the semiconductor thin film layer.

[0070] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for transferring a semiconductor thin film layer, characterized in that: The semiconductor thin film layer transfer method comprises the following steps: Providing a transfer substrate, wherein the transfer substrate has a first surface and a second surface disposed opposite to each other, and forming a composite porous structure layer on the first surface of the transfer substrate; Growing a semiconductor thin film layer on the surface of the composite porous structure layer; Providing a supporting substrate, and performing a bonding process on the supporting substrate and the semiconductor thin film layer to form a temporary bonding substrate; placing the temporary bonding substrate in a fluid medium so that the fluid medium enters into the composite porous structure layer; The ambient temperature and / or ambient pressure of the temporary bonding substrate is changed so that the temporary bonding substrate is transversely cracked along the composite porous structure layer, thereby completing the transfer of the semiconductor thin film layer to the supporting substrate.

2. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: The ambient temperature of the temporary bonding substrate is lowered to allow the fluid medium to crystallize in the composite porous structure layer, so that the temporary bonding substrate is transversely cracked along the composite porous structure layer.

3. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: Increasing the ambient temperature and / or ambient pressure of the temporary bonding substrate allows the fluid medium to diffuse more easily into the composite porous structure layer and rapidly corrode the composite porous structure layer, causing the temporary bonding substrate to undergo lateral cracking along the composite porous structure layer.

4. The method for transferring a semiconductor thin film layer according to any one of claims 1 to 3, characterized in that: The composite porous structure layer includes a plurality of porous layers with different porosities.

5. The method for transferring a semiconductor thin film layer according to claim 4, characterized in that: The composite porous structure layer includes a first porous layer and a second porous layer with different porosities, and the porosity of the first porous layer close to the first surface of the transfer substrate is greater than the porosity of the second porous layer far from the first surface of the transfer substrate.

6. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: The method for forming the composite porous structure layer includes an electrochemical corrosion process, and after completing the electrochemical corrosion process, the composite porous structure layer needs to be oxidized to form an oxide film layer that completely covers or partially covers the surface of the micro-nano structure inside the composite porous structure layer.

7. The method for transferring a semiconductor thin film layer according to claim 2, characterized in that: Before growing the semiconductor thin film layer on the composite porous structure layer, the method also includes the steps of selectively removing the oxide film covering the composite porous structure layer at a depth of 5 nm to 1 μm extending downward from the surface of the composite porous structure layer, and annealing the transfer substrate in a hydrogen atmosphere or a mixed atmosphere of hydrogen and an inert gas, wherein the annealing temperature ranges from 300 to 1400°C.

8. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: Before the support substrate is bonded to the semiconductor film, the method further includes forming a functional material layer on the first surface of the support substrate or on the semiconductor film.

9. The method for transferring a semiconductor thin film layer according to claim 5, characterized in that: The functional material layer includes at least one of a single crystal semiconductor layer, a polycrystalline semiconductor layer, an amorphous material layer, an insulating dielectric layer, a piezoelectric material layer, a metal layer, and a compound conductive layer.

10. The method for transferring a semiconductor thin film layer according to claim 7, characterized in that: Before forming a temporary bonding substrate, a step of forming a patterned cavity structure is also included, wherein the patterned cavity structure can be completely located in the functional material layer in the depth direction, or span the interface between the functional material layer and the supporting substrate, or span the interface between the functional material layer and the semiconductor thin film layer, or be completely located in the supporting substrate and connected to the functional material layer.

11. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: The fluid medium includes at least one of CO2, O2, N2, water, liquid acid, salt solution, liquid organic matter, etc., and the fluid medium can crystallize at a certain temperature.

12. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: After placing the temporary bonding substrate in the fluid medium, the method further includes placing the temporary bonding substrate and the fluid medium in a sealed container, and performing pressurization and temperature increase steps.

13. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: After the temporary bonding substrate is transversely cracked along the composite porous structure layer, the method further comprises the step of performing at least one of thinning, polishing, homoepitaxial growth or heteroepitaxial growth on the semiconductor film layer.

14. The method for transferring a semiconductor thin film layer according to claim 1, characterized in that: The bonding process includes one of a hydrophilic bonding process, a thermal compression bonding process, a surface plasma activation bonding process or an anodic bonding process.

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