Substrate removing device and substrate removing method

Abstract

The invention provides a substrate removing device and a substrate removing method, and belongs to the technical field of photoelectron manufacturing. The substrate removing device comprises a corrosion tank, a connecting base and a liquid injection part, an injection port and a discharge port are respectively formed in two opposite tank walls of the corrosion tank, the liquid injection piece is used for injecting a corrosion solution into the corrosion tank from the injection port, so that the corrosion solution flows to the discharge port from the injection port, and the connecting base is positioned at the bottom of the corrosion tank and is used for mounting an epitaxial wafer. According to the embodiment of the invention, the problem that part of the epitaxial layer is corroded and damaged due to inconsistent corrosion rates of the local region of the epitaxial wafer in the process of removing the GaAs substrate can be improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of optoelectronic manufacturing, and in particular to a substrate removal device and method. Background Art

[0002] Light emitting diodes (LEDs) are a highly influential new product in the optoelectronics industry. They have the characteristics of small size, long service life, rich colors, and low energy consumption. They are widely used in lighting, display screens, signal lights, backlight sources, toys and other fields.

[0003] In the related art, when preparing light-emitting diodes, an epitaxial layer is first grown on a GaAs substrate, and then the epitaxial layer is bonded to a sapphire substrate. The GaAs substrate on the epitaxial layer is then removed by immersing the epitaxial wafer in a solution.

[0004] However, during the soaking process, the epitaxial wafer often floats up and down in the solution, which causes different etching rates in different areas of the epitaxial wafer surface. Therefore, within the same etching time, some areas of the epitaxial wafer will continue to erode the epitaxial layer after etching the GaAs substrate, causing damage to the epitaxial layer. Summary of the Invention

[0005] The present disclosure provides a substrate removal device and method that can improve the problem of partial epitaxial layer corrosion damage caused by inconsistent etching rates in local areas of the epitaxial wafer during GaAs substrate removal. The technical solution is as follows:

[0006] On the one hand, an embodiment of the present disclosure provides a substrate removal device, which includes: an etching groove, a connecting base and a liquid injection part; the two opposite groove walls of the etching groove are respectively provided with an injection port and a discharge port, and the liquid injection part is used to inject etching solution into the etching groove from the injection port so that the etching solution flows from the injection port to the discharge port, and the connecting base is located at the bottom of the etching groove, and the connecting base is used to install the epitaxial wafer.

[0007] In one implementation of the present disclosure, the flow rate at which the liquid injection piece injects the corrosion solution into the corrosion tank is 1 mm / s to 5 mm / s.

[0008] In another implementation of the present disclosure, the epitaxial wafer includes a sapphire substrate, an epitaxial layer and a GaAs substrate stacked in sequence; the connecting base includes a suction cup, which is located at the bottom of the etching groove, and the suction cup is used to adsorb the surface of the sapphire substrate away from the epitaxial layer.

[0009] In another implementation of the present disclosure, the removal device further includes a fluid replenishing member, which is located in the corrosion tank and arranged between the injection port and the discharge port, and is used to inject the corrosion solution into the corrosion tank.

[0010] In another implementation of the present disclosure, the removal device includes multiple liquid replenishing parts, which are arranged at intervals, and the orthographic projection of each liquid replenishing part on the bottom of the etching groove is located within the orthographic projection of the epitaxial wafer on the bottom of the etching groove.

[0011] In another implementation of the present disclosure, the removal device further includes a detection member, which is located in the etching groove and is used to detect the thickness of the GaAs substrate of the epitaxial wafer.

[0012] In another implementation of the present disclosure, the removal device includes a plurality of detection members, which are arranged at intervals, and the orthographic projection of each detection member on the bottom of the etching groove is located within the orthographic projection of the epitaxial wafer on the bottom of the etching groove.

[0013] In another implementation of the present disclosure, the plurality of detection parts include a detection reference part and a detection proofreading part, the detection reference part being closest to the injection port among the plurality of detection parts, the detection reference part being used to detect the thickness reference value, and the detection proofreading part being used to detect the thickness proofreading value; the detection proofreading part corresponds one-to-one to the fluid replenishing part, and the orthographic projection of the detection proofreading part on the bottom of the corrosion groove at least partially overlaps with the orthographic projection of the corresponding fluid replenishing part on the bottom of the corrosion groove.

[0014] In another embodiment of the present disclosure, the removal device further includes a controller, which is electrically connected to the detection reference part, the detection proofreading part and the fluid replenishing part respectively; the controller is configured to control the fluid replenishing part corresponding to the detection proofreading part to increase the rate of injecting the corrosive solution when it is detected that the thickness proofreading value detected by the detection proofreading part is greater than the thickness reference value; and to control the fluid replenishing part corresponding to the detection proofreading part to reduce the rate of injecting the corrosive solution when the thickness proofreading value detected by the detection proofreading part is less than the thickness reference value.

[0015] On the other hand, an embodiment of the present disclosure also provides a method for removing a substrate, which is implemented using the removal device as described above. The removal method includes: mounting an epitaxial wafer on a connecting base so that the GaAs substrate of the epitaxial wafer is away from the bottom of the etching groove; controlling the liquid injection part to inject a corrosive solution into the etching groove through the injection port so that the corrosive solution flows from the injection port to the discharge port to corrode the GaAs substrate.

[0016] The beneficial effects of the technical solutions provided by the embodiments of the present disclosure include at least:

[0017] The substrate removal device provided in the disclosed embodiment includes a connecting base within an etching tank. The connecting base is used to mount an epitaxial wafer, allowing the epitaxial wafer to be fixed to the bottom of the etching tank via the connecting base. Furthermore, two opposing walls of the etching tank are provided with an inlet and an outlet. A liquid injection member can inject an etching solution into the etching tank from the inlet, causing the etching solution to flow from the inlet to the outlet, thereby forming a flowing etching solution within the etching tank. Thus, when the removal device is used to etch the GaAs substrate of the epitaxial wafer, the connecting base secures the epitaxial wafer to the bottom of the etching tank, preventing the epitaxial wafer from floating up and down within the etching solution. Furthermore, the etching solution flows from the inlet to the outlet during injection, meaning that the etching solution continuously flows. This ensures that the etching solution within the etching tank is always fresh, ensuring that the concentration of the etching solution in each region of the etching tank is consistent. This effectively avoids the problem of different etching rates in different regions on the surface of the epitaxial wafer, allowing the GaAs substrate in each region of the epitaxial wafer to be uniformly etched, preventing damage to the epitaxial layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 1 is a schematic structural diagram of a substrate removal device provided in an embodiment of the present disclosure;

[0020] Figure 2 Schematic diagram of the arrangement of a fluid infusion component provided by an embodiment of the present disclosure;

[0021] Figure 3 is a schematic diagram of the arrangement of detection components provided by an embodiment of the present disclosure;

[0022] Figure 4 This is a flow chart of a substrate removal method provided by an embodiment of the present disclosure.

[0023] The descriptions of the marks in the figure are as follows:

[0024] 10. Corrosion tank; 11. Inlet; 12. Discharge port;

[0025] 20. Connect the base;

[0026] 30. Liquid injection parts;

[0027] 40. Epitaxial wafer; 41. Sapphire substrate; 42. Epitaxial layer; 43. GaAs substrate;

[0028] 50. Fluid refill kit;

[0029] 60. Inspection part; 61. Inspection reference part; 62. Inspection proofreading part. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0031] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by a person of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," "third," and similar words used in the patent specification and claims of this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish between different components. Similarly, terms such as "a" or "an" do not indicate a quantitative limitation, but rather indicate the presence of at least one. Terms such as "include" or "comprise" mean that the elements or objects preceding "include" or "comprises" encompass the elements or objects listed after "include" or "comprises," and their equivalents, and do not exclude other elements or objects. Terms such as "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," "right," "top," and "bottom" are used only to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0032] Figure 1 Schematic diagram of a substrate removal device provided by an embodiment of the present disclosure. Figure 1 As shown, the removal device includes: a corrosion tank 10, a connecting base 20 and a liquid injection part 30.

[0033] like Figure 1 As shown, the two opposite walls of the etching tank 10 are respectively provided with an injection port 11 and a discharge port 12. The liquid injection part 30 is used to inject the etching solution into the etching tank 10 from the injection port 11, so that the etching solution flows from the injection port 11 to the discharge port 12. The connecting base 20 is located at the bottom of the etching tank 10, and the connecting base 20 is used to install the epitaxial wafer 40.

[0034] The substrate removal device provided in the disclosed embodiment includes a connecting base 20 disposed within an etching tank 10. The connecting base 20 is used to mount an epitaxial wafer 40, allowing the epitaxial wafer 40 to be secured to the bottom of the etching tank 10 via the connecting base 20. Furthermore, an inlet 11 and an outlet 12 are disposed on opposing walls of the etching tank 10. A liquid injection member 30 can inject an etching solution into the etching tank 10 from the inlet 11, causing the etching solution to flow from the inlet 11 to the outlet 12, thereby forming a flowing etching solution within the etching tank 10. Thus, when the removal device is used to etch the GaAs substrate 43 of the epitaxial wafer 40, the connecting base 20 secures the epitaxial wafer 40 to the bottom of the etching tank 10, preventing the epitaxial wafer 40 from floating up and down within the etching solution. Furthermore, the etching solution flows from the inlet 11 to the outlet 12 during injection, meaning the etching solution continuously flows. This ensures that the etching solution within the etching tank 10 is always fresh, ensuring that the concentration of the etching solution in all areas of the etching tank 10 is consistent. This can effectively avoid the problem of different etching rates in different areas on the surface of the epitaxial wafer 40 , allowing the GaAs substrate 43 in each area of ​​the epitaxial wafer 40 to be uniformly corroded, thereby preventing damage to the epitaxial layer 42 .

[0035] For example, the etching solution may include ammonia, hydrogen peroxide, and water. The temperature of the etching solution may be 45°C to 55°C. At this temperature, the ammonia and hydrogen peroxide in the etching solution synergistically attack gallium sites in gallium arsenide, forming soluble gallium hydride while releasing elemental arsenic, ultimately achieving uniform and thorough etching.

[0036] Optionally, the removal device may further include a storage box and a collection box. The storage box is used to store the corrosive solution. The injection piece 30 is connected between the storage box and the injection port 11 so that the injection piece 30 can transport the corrosive solution to the corrosion tank 10. The collection box is connected to the discharge port 12 through a pipeline to collect the corrosive solution discharged from the corrosion tank 10.

[0037] For example, the liquid injection member 30 can be a micro electric pump, the suction port of the electric pump is connected to the storage tank, and the discharge port of the electric pump is connected to the injection port 11. When the electric pump is in operation, it sucks the oil in the storage tank through the suction port and delivers the corrosive solution to the injection port 11 through the discharge port.

[0038] The rate at which the electric pump delivers the corrosive solution can be adjusted by controlling the working power of the electric pump.

[0039] Optionally, the flow rate of the etching solution injected into the etching tank 10 by the liquid injection member 30 is 1 mm / s to 5 mm / s.

[0040] A flow rate that is too low for the etching solution can cause reactant retention and the formation of microscopic etching pits; a flow rate that is too high can cause turbulence and surface damage. By controlling the etching solution flow rate within the above range, the etching solution is evenly distributed across the surface of the GaAs substrate 43, minimizing local concentration variations. This helps avoid over- or under-etching caused by uneven solution composition, thereby improving overall process stability.

[0041] Exemplarily, the flow rate of the etching solution injected into the etching tank 10 by the liquid injection part 30 is 1 mm / s.

[0042] Alternatively, as Figure 1 As shown, the epitaxial wafer 40 includes a sapphire substrate 41, an epitaxial layer 42 and a GaAs substrate 43 stacked in sequence.

[0043] The sapphire substrate 41 is used as the carrier of the epitaxial layer 42 because the sapphire substrate 41 has a relatively high light transmittance, and the sapphire material is relatively hard and has relatively stable chemical properties, which can make the light-emitting diode have good light-emitting effect and stability.

[0044] In the embodiment of the present disclosure, the epitaxial layer 42 includes a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer sequentially stacked on the sapphire substrate 41 .

[0045] In the embodiment of the present disclosure, one of the first semiconductor layer and the second semiconductor layer is a p-type layer, and the other of the first semiconductor layer and the second semiconductor layer is an n-type layer.

[0046] As an example, the first semiconductor layer is an n-type layer, and the second semiconductor layer is a p-type layer.

[0047] Optionally, the first semiconductor layer is an n-type AlGaInP layer, and the thickness of the n-type AlGaInP layer may be 0.5 μm to 3 μm.

[0048] Optionally, the multi-quantum well layer includes an AlGaInP quantum well layer and an AlGaInP quantum barrier layer grown alternately. The Al content in the AlGaInP quantum well layer and the AlGaInP quantum barrier layer is different. The multi-quantum well layer may include 3 to 8 periods of AlGaInP quantum well layers and AlGaInP quantum barrier layers alternately stacked.

[0049] As an example, in the embodiment of the present disclosure, the multi-quantum well layer includes five periods of alternately stacked AlGaInP quantum well layers and AlGaInP quantum barrier layers.

[0050] Optionally, the thickness of the multi-quantum well layer may be 150 nm to 200 nm.

[0051] Optionally, the second semiconductor layer is an indium-doped p-type AlInP layer, and the thickness of the p-type AlInP layer may be 0.5 μm to 3 μm.

[0052] like Figure 1 As shown, the connection base 20 includes a suction cup, which is located at the bottom of the etching groove 10 and is used to absorb the surface of the sapphire substrate 41 away from the epitaxial layer 42.

[0053] The chuck's evenly distributed suction force ensures the epitaxial wafer 40 remains in a stable position during the etching process. Furthermore, the chuck secures the sapphire substrate 41 through non-contact suction, avoiding scratches or particle contamination that can occur with traditional mechanical fixtures. The chuck maintains the integrity of the substrate surface and reduces defects caused by contact friction.

[0054] Alternatively, as Figure 1 As shown, the removal device further includes a fluid replenishing member 50 , which is located in the corrosion tank 10 and arranged between the injection port 11 and the discharge port 12 . The fluid replenishing member 50 is used to inject the corrosion solution into the corrosion tank 10 .

[0055] By providing the liquid replenishing member 50 , the corrosion solution can be replenished into the corrosion tank 10 in a timely manner, thereby avoiding the problem of inconsistent corrosion rates caused by the corrosion solution concentration being too low in a local area of ​​the corrosion tank 10 .

[0056] For example, the fluid replenishing member 50 can be a micro electric pump. The suction port of the electric pump is connected to the storage tank, and the discharge port of the electric pump is located above the corrosion tank 10. When the electric pump is in operation, it draws the oil from the storage tank through the suction port and discharges the oil from the top of the corrosion tank 10 downward through the discharge port.

[0057] The rate at which the electric pump delivers the corrosive solution can be adjusted by controlling the working power of the electric pump.

[0058] Figure 2 FIG. 5 is a schematic diagram of the arrangement of a fluid infusion component 50 provided in an embodiment of the present disclosure. Figure 2 As shown, the removal device includes multiple liquid replenishing parts 50, which are arranged at intervals, and the orthographic projection of each liquid replenishing part 50 on the bottom of the etching groove 10 is located within the orthographic projection of the epitaxial wafer 40 on the bottom of the etching groove 10.

[0059] For example, Figure 2 As shown, each of the liquid replenishing members 50 is disposed directly above the epitaxial wafer 40. This ensures that the etching solution replenished by the liquid replenishing members 50 can fall into the area where the epitaxial wafer 40 is located. Furthermore, since the liquid replenishing members 50 are spaced apart in the areas directly above the epitaxial wafer 40, the etching solution can be replenished in different areas of the epitaxial wafer 40 using each of the liquid replenishing members 50, thereby achieving the goal of controlling the etching solution concentration at various locations on the GaAs substrate 43 to be consistent.

[0060] For example, Figure 1 、 2 As shown, the liquid replenishing member 50 may not be provided in the area of ​​the epitaxial wafer 40 near the injection port 11. Since the etching solution in the area near the injection port 11 is fresh etching solution that has just been injected into the etching tank 10 from the liquid injection member 30, the etching solution concentration at this time meets the requirements. Therefore, the liquid replenishing member 50 does not need to be provided in the area of ​​the epitaxial wafer 40 near the injection port 11, thereby saving costs.

[0061] Alternatively, as Figure 1 As shown, the removal device further includes a detection member 60 , which is located in the etching groove 10 , and is used to detect the thickness of the GaAs substrate 43 of the epitaxial wafer 40 .

[0062] By arranging the detection member 60 above the etching groove 10 to detect the thickness of the GaAs substrate 43, the etching condition of the GaAs substrate 43 can be understood in real time to determine whether the etching rates of different regions of the GaAs substrate 43 are consistent.

[0063] For example, the inspection member 60 may be a probe-type step meter or an optical profiler.

[0064] Figure 3 FIG. 6 is a schematic diagram of the arrangement of a detection member 60 provided in an embodiment of the present disclosure. Figure 3 As shown, the removal device includes a plurality of detection members 60 , which are arranged at intervals, and the orthographic projection of each detection member 60 on the bottom of the etching groove 10 is located within the orthographic projection of the epitaxial wafer 40 on the bottom of the etching groove 10 .

[0065] For example, Figure 3 As shown, each detection member 60 is disposed directly above the epitaxial wafer 40. This ensures that the detection members 60 can detect the thickness of the GaAs substrate 43. Furthermore, since the detection members 60 are spaced apart in various areas directly above the epitaxial wafer 40, the thickness of different areas of the GaAs substrate 43 can be detected by using each detection member 60, thereby achieving the purpose of understanding the corrosion rate of various locations on the GaAs substrate 43.

[0066] Alternatively, as Figure 1 、 3 As shown, the multiple detection parts 60 include a detection reference part 61 and a detection calibration part 62. The detection reference part 61 closest to the injection port 11 is the detection reference part 61. The detection reference part 61 is used to detect the thickness reference value, and the detection calibration part 62 is used to detect the thickness calibration value.

[0067] Because the etching solution in the area near injection port 11 is freshly injected into etching tank 10 from injection member 30, the etching solution concentration meets the requirements, indicating that the etching rate of GaAs substrate 43 in this area also meets the design requirements. A detection reference member 61 is installed in the area near injection port 11 of epitaxial wafer 40. Using the thickness reference value detected by detection reference member 61 as a reference, it can quickly determine whether the etching rate of other areas of GaAs substrate 43 is too fast or too slow.

[0068] like Figure 1 As shown, the detection and calibration component 62 corresponds to the liquid replenishing component 50 one by one, and the orthographic projection of the detection and calibration component 62 on the bottom of the etching tank 10 at least partially overlaps with the orthographic projection of the corresponding liquid replenishing component 50 on the bottom of the etching tank 10.

[0069] Since the detection component 60 detects that the corrosion rate is too fast or too slow, it is necessary to use the liquid replenishing component 50 to replenish or reduce the replenishment of the corrosion solution. Therefore, the detection and calibration component 62 and the corresponding liquid replenishing component 50 are arranged in the same position to ensure that the liquid replenishing component 50 replenishes or reduces the replenishment of the corrosion solution in the correct position.

[0070] Optionally, the removal device further includes a controller, which is electrically connected to the detection reference component 61 , the detection calibration component 62 and the liquid replenishing component 50 , respectively.

[0071] For example, the controller may be a Programmable Logic Controller (PLC). A PLC can implement logic control, sequential operations, timing counting, and data processing through programming, and can control mechanical equipment and production processes with the help of digital or analog signal input / output modules.

[0072] The controller is configured to control the liquid replenishing member 50 corresponding to the detection and calibration member 62 to increase the rate of injecting the corrosion solution when it is detected that the thickness calibration value detected by the detection and calibration member 62 is greater than the thickness reference value.

[0073] When the thickness calibration value detected by the detection and calibration component 62 is less than the thickness reference value, the liquid replenishing component 50 corresponding to the detection and calibration component 62 is controlled to reduce the rate of injecting the corrosion solution.

[0074] In the embodiment of the present disclosure, when the thickness calibration value detected by the detection and calibration part 62 is greater than the thickness reference value, it indicates that the corrosion rate of the area where the detection and calibration part 62 is located is too slow. At this time, the controller controls the liquid replenishing part 50 corresponding to the detection and calibration part 62 to increase the rate of injecting the corrosion solution, thereby replenishing the corrosion solution in the area and increasing the concentration of the corrosion solution in the area to increase the corrosion rate.

[0075] If the thickness calibration value detected by the detection and calibration component 62 is less than the thickness reference value, it indicates that the etching rate in the area where the detection and calibration component 62 is located is too high. In this case, the controller controls the liquid replenishing component 50 corresponding to the detection and calibration component 62 to stop injecting the etching solution or reduce the injection rate of the etching solution, thereby replenishing the etching solution in the area, increasing and reducing the concentration of the etching solution in the area, and thus slowing the etching rate. Therefore, by setting up the controller, the etching of the GaAs substrate 43 can be automated.

[0076] Figure 4 1 is a flow chart of a substrate removal method provided by an embodiment of the present disclosure. The removal method is implemented using the removal device described above. Figure 4 As shown, the removal method includes:

[0077] S11: Mount the epitaxial wafer on a connection base.

[0078] The GaAs substrate of the epitaxial wafer is far away from the bottom of the etching groove.

[0079] Illustratively, the epitaxial wafer may include a sapphire substrate, an epitaxial layer, and a GaAs substrate.

[0080] The epitaxial layer may include a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer sequentially stacked on a substrate. The first semiconductor layer has a first conductivity type, the second semiconductor layer has a second conductivity type different from the first conductivity type, and the multi-quantum well layer is used to generate light through electron-hole recombination.

[0081] One of the first semiconductor layer and the second semiconductor layer is a p-type layer, and the other of the first semiconductor layer and the second semiconductor layer is an n-type layer.

[0082] As an example, the first semiconductor layer is a p-type layer, and the second semiconductor layer is an n-type layer.

[0083] In the embodiment of the present disclosure, the production of an epitaxial wafer may include the following steps:

[0084] The first step is to provide a GaAs wafer.

[0085] In the second step, a first semiconductor layer, a multi-quantum well layer and a second semiconductor layer are grown in sequence on the GaAs wafer.

[0086] Exemplarily, the first semiconductor layer is an indium-doped p-type AlInP layer, and the thickness of the p-type AlInP layer may be 0.5 μm to 3 μm.

[0087] For example, the second semiconductor layer may be an n-type AlGaInP layer, and the thickness of the n-type AlGaInP layer may be 0.5 μm to 3 μm.

[0088] Optionally, the multi-quantum well layer includes an AlGaInP quantum well layer and an AlGaInP quantum barrier layer grown alternately. The Al content in the AlGaInP quantum well layer and the AlGaInP quantum barrier layer is different. The multi-quantum well layer may include 3 to 8 periods of AlGaInP quantum well layers and AlGaInP quantum barrier layers alternately stacked.

[0089] As an example, in the embodiment of the present disclosure, the multi-quantum well layer includes five periods of alternately stacked AlGaInP quantum well layers and AlGaInP quantum barrier layers.

[0090] Optionally, the thickness of the multi-quantum well layer may be 150 nm to 200 nm.

[0091] In the second step, an etching stop layer may be grown before growing the second semiconductor layer, and an AlInP carrier confinement layer may be grown before growing the multi-quantum well layer.

[0092] A GaP window layer may be further grown after the second semiconductor layer is grown, wherein the thickness of the GaP window layer is 10,000 angstroms to 20,000 angstroms.

[0093] Exemplarily, the thickness of the GaP window layer is 3 μm.

[0094] In the third step, the second semiconductor layer is bonded to the sapphire substrate, and the bonding temperature is set to 300°C.

[0095] Step S12: controlling the liquid injection part to inject the etching solution into the etching tank through the injection port, so that the etching solution flows from the injection port to the discharge port to etch the GaAs substrate.

[0096] For example, the etching solution may include ammonia, hydrogen peroxide, and water. The temperature of the etching solution may be 45°C to 55°C. At this temperature, the ammonia and hydrogen peroxide in the etching solution synergistically attack gallium sites in gallium arsenide, forming soluble gallium hydride while releasing elemental arsenic, ultimately achieving uniform and thorough etching.

[0097] Optionally, the removal device may also include a storage box and a collection box, the storage box is used to store the corrosive solution, the injection piece is connected between the storage box and the injection port so that the injection piece can transport the corrosive solution to the corrosion tank, and the collection box is connected to the discharge port through a pipeline to collect the corrosive solution discharged from the corrosion tank.

[0098] For example, the injection member can be a micro electric pump, wherein the suction port of the electric pump is connected to the storage tank, and the discharge port of the electric pump is connected to the injection port. When the electric pump is in operation, it sucks the oil in the storage tank through the suction port and delivers the corrosive solution to the injection port through the discharge port.

[0099] The rate at which the electric pump delivers the corrosive solution can be adjusted by controlling the working power of the electric pump.

[0100] Optionally, the injection member injects the etching solution into the etching tank at a flow rate of 1 mm / s to 5 mm / s. Exemplarily, the injection member injects the etching solution into the etching tank at a flow rate of 1 mm / s.

[0101] During the etching process of the GaAs substrate, the thickness of different regions of the GaAs substrate can be detected by multiple detection elements.

[0102] Among them, the multiple detection parts include detection reference parts and detection correction parts. The detection reference part closest to the injection port is the detection reference part. The detection reference part is used to detect the thickness reference value, and the detection correction part is used to detect the thickness correction value.

[0103] In an embodiment of the present disclosure, when the thickness calibration value detected by the detection and calibration part is greater than the thickness reference value, it indicates that the corrosion rate of the area where the detection and calibration part is located is too slow. At this time, the controller controls the liquid replenishing part corresponding to the detection and calibration part to increase the rate of injecting the corrosion solution, thereby replenishing the corrosion solution in the area and increasing the concentration of the corrosion solution in the area to increase the corrosion rate.

[0104] When the thickness calibration value detected by the detection and calibration part is less than the thickness reference value, it indicates that the corrosion rate in the area where the detection and calibration part is located is too fast. At this time, the controller controls the liquid replenishing part corresponding to the detection and calibration part to stop injecting the corrosion solution or reduce the injection rate of the corrosion solution, thereby replenishing the corrosion solution in the area, increasing and reducing the concentration of the corrosion solution in the area, and slowing down the corrosion rate.

[0105] The substrate removal method provided by the embodiment of the present disclosure first installs the epitaxial wafer through the connecting base so that the epitaxial wafer can be fixed to the bottom of the etching tank through the connecting base. At the same time, the two opposite groove walls of the etching tank are provided with an injection port and an outlet port, and then the etching solution is injected into the etching tank from the injection port through the injection part, so that the etching solution flows from the injection port to the outlet port, thereby forming a flowing etching solution in the etching tank. In this way, when etching the GaAs substrate of the epitaxial wafer, since the connecting base fixes the epitaxial wafer to the bottom of the etching tank, the epitaxial wafer will not float up and down in the etching solution; at the same time, the etching solution flows from the injection port to the outlet port during the injection process, that is, the etching solution also flows continuously, which can ensure that the etching solution in the etching tank is always in a fresh state, so that the concentration of the etching solution in various areas of the etching tank tends to be consistent. This can effectively avoid the problem of different etching rates in different areas on the surface of the epitaxial wafer, so that the GaAs substrate in each area of ​​the epitaxial wafer can be uniformly corroded, and damage to the epitaxial layer is prevented.

[0106] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. The data therein merely represent illustrative examples. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A substrate removal device, characterized in that: The removal device comprises: a corrosion tank (10), a connecting base (20) and a liquid injection part (30); The two opposite groove walls of the etching groove (10) are respectively provided with an injection port (11) and a discharge port (12); the liquid injection member (30) is used to inject the etching solution into the etching groove (10) from the injection port (11), so that the etching solution flows from the injection port (11) to the discharge port (12); the connecting base (20) is located at the groove bottom of the etching groove (10); the connecting base (20) is used to install the epitaxial wafer (40).

2. The removal device according to claim 1, characterized in that The injection piece (30) injects the etching solution into the etching tank (10) at a flow rate of 1 mm / s to 5 mm / s.

3. The removal device according to claim 1, characterized in that The epitaxial wafer (40) comprises a sapphire substrate (41), an epitaxial layer (42) and a GaAs substrate (43) stacked in sequence; The connection base (20) comprises a suction cup, the suction cup is located at the bottom of the etching groove (10), and the suction cup is used to absorb the surface of the sapphire substrate (41) away from the epitaxial layer (42).

4. The removal device according to any one of claims 1 to 3, characterized in that The removal device further comprises a liquid replenishing member (50), the liquid replenishing member (50) being located in the corrosion tank (10) and arranged between the injection port (11) and the discharge port (12), the liquid replenishing member (50) being used to inject the corrosion solution into the corrosion tank (10).

5. The removal device according to claim 4, characterized in that The removal device comprises a plurality of liquid replenishing parts (50), the plurality of liquid replenishing parts (50) are arranged at intervals, and the orthographic projection of each of the liquid replenishing parts (50) on the bottom of the etching groove (10) is located within the orthographic projection of the epitaxial wafer (40) on the bottom of the etching groove (10).

6. The removal device according to claim 5, characterized in that The removal device further comprises a detection member (60), the detection member (60) being located in the etching groove (10), and the detection member (60) being used to detect the thickness of the GaAs substrate (43) of the epitaxial wafer (40).

7. The removal device according to claim 6, characterized in that The removal device comprises a plurality of detection members (60), the plurality of detection members (60) are arranged at intervals, and the orthographic projection of each detection member (60) on the bottom of the etching groove (10) is located within the orthographic projection of the epitaxial wafer (40) on the bottom of the etching groove (10).

8. The removal device according to claim 7, characterized in that The plurality of detection parts (60) include a detection reference part (61) and a detection calibration part (62). The detection reference part (61) closest to the injection port (11) among the plurality of detection parts (60) is the detection reference part (61). The detection reference part (61) is used to detect a thickness reference value, and the detection calibration part (62) is used to detect a thickness calibration value. The detection and calibration component (62) corresponds to the liquid replenishing component (50) one by one, and the orthographic projection of the detection and calibration component (62) on the bottom of the corrosion groove (10) at least partially overlaps with the orthographic projection of the corresponding liquid replenishing component (50) on the bottom of the corrosion groove (10).

9. The removal device according to claim 8, characterized in that The removal device further includes a controller, wherein the controller is electrically connected to the detection reference component (61), the detection calibration component (62), and the liquid replenishing component (50) respectively; The controller is configured to control the liquid replenishing part (50) corresponding to the detection and calibration part (62) to increase the rate of injecting the corrosion solution when it is detected that the thickness calibration value detected by the detection and calibration part (62) is greater than the thickness reference value; When the thickness calibration value detected by the detection and calibration component (62) is less than the thickness reference value, the liquid replenishing component (50) corresponding to the detection and calibration component (62) is controlled to reduce the rate of injecting the corrosion solution.

10. A method for removing a substrate, characterized in that: The removal method is implemented using the removal device according to any one of claims 1 to 9, and the removal method includes: Mounting the epitaxial wafer on a connection base so that the GaAs substrate of the epitaxial wafer is away from the bottom of the etching groove; The liquid injection part is controlled to inject the etching solution into the etching tank through the injection port, so that the etching solution flows from the injection port to the discharge port to etch the GaAs substrate.

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