Epitaxial wafer peeling apparatus

Abstract

The application relates to an epitaxial wafer stripping device, which comprises a plurality of chambers, the plurality of chambers at least comprising a stripping chamber, a cleaning and drying chamber, a heating chamber and a deposition chamber; the epitaxial wafer is in a vacuum environment during transportation among different chambers; the stripping chamber is used for stripping a substrate from the epitaxial wafer; the cleaning and drying chamber is used for cleaning and drying the stripped epitaxial wafer; the heating chamber is internally provided with a heating device; the heating device is used for heating the cleaned and dried epitaxial wafer, so as to remove moisture and reduce the deposition time of the epitaxial wafer; and the deposition chamber is used for deposition based on the heated epitaxial wafer. The application can effectively improve the performance of a semiconductor device.

Description

Technical Field

[0001] This application relates to the field of integrated circuit technology, and in particular to an epitaxial wafer stripping device. Background Technology

[0002] Currently, some semiconductor devices (such as gallium nitride devices) are typically formed on substrates such as sapphire using heteroepitaxial growth. However, as heteroepitaxial substrates, sapphire and similar materials suffer from drawbacks such as high lattice mismatch, high thermal mismatch, poor thermal conductivity, and poor electrical conductivity. This has spurred research into lift-off techniques. Lift-off techniques remove gallium nitride epitaxial wafers from substrates such as sapphire, allowing for homoepitaxial growth on these wafers to form the device. Lift-off techniques overcome the adverse effects of sapphire substrates on device fabrication.

[0003] However, devices formed using the current stripping technique often fail to achieve the desired performance. Summary of the Invention

[0004] Based on this, embodiments of this application provide an epitaxial wafer stripping device and a semiconductor manufacturing system that can improve the performance of semiconductor devices.

[0005] An epitaxial wafer stripping device includes multiple chambers, each chamber including at least a stripping chamber, a cleaning and drying chamber, a heating chamber, and a deposition chamber; the epitaxial wafer is transported between different chambers in a vacuum environment.

[0006] The stripping chamber separates the substrate from the epitaxial wafer, and the cleaning and drying chamber is used to clean and dry the stripped epitaxial wafer. The heating chamber is located between the cleaning and drying chamber and the deposition chamber, and is equipped with a heating device inside. The heating device is used to heat the cleaned and dried epitaxial wafer to remove moisture and reduce the deposition time of the epitaxial wafer. The deposition chamber performs deposition based on the heated epitaxial wafer.

[0007] In one embodiment, the stripping cavity is provided with a laser stripping device, the laser stripping device comprising:

[0008] A laser, used to emit laser light;

[0009] The photomask includes multiple light-transmitting holes, each of which is equipped with a light valve, which is used to control whether the light-transmitting hole it is located in transmits light.

[0010] In one embodiment,

[0011] A mask control element controls the opening and closing of each optical valve according to the size of the epitaxial wafer.

[0012] In one embodiment, the heating cavity is further provided with a temperature detection device, which is used to detect the temperature of the epitaxial wafer. The heating device is electrically connected to the temperature detection device and is used to heat the epitaxial wafer according to the detection result of the temperature detection device.

[0013] In one embodiment,

[0014] The epitaxial wafer stripping device also includes a transfer cavity and a control device;

[0015] The transfer chamber is equipped with a robotic arm and is surrounded by other chambers, including a transfer gate valve. When the transfer gate valve is closed, it isolates the interior of the transfer chamber from the outside. The stripping chamber has a stripping gate valve on the side facing the transfer chamber, which also isolates the interior of the transfer chamber from the outside when closed. The cleaning and drying chamber has a cleaning gate valve on the side facing the transfer chamber, which isolates the interior of the cleaning and drying chamber from the outside when closed. The heating chamber has a heating gate valve on the side facing the transfer chamber, which isolates the interior of the heating chamber from the outside when closed. The deposition chamber has a deposition gate valve on the side facing the transfer chamber, which isolates the interior of the deposition chamber from the outside when closed. The transfer chamber, stripping chamber, cleaning and drying chamber, heating chamber, and deposition chamber are all connected to a vacuum system to allow the epitaxial wafer to be transferred between the transfer chamber and other chambers under vacuum conditions.

[0016] A control device is used to control the rotation of the conveying cavity.

[0017] In one embodiment, the epitaxial wafer stripping device further includes a peripheral cavity, in which the conveying cavity, the stripping cavity, the cleaning and drying cavity, the heating cavity, and the deposition cavity are all located, and the peripheral cavity is also connected to a vacuum system.

[0018] In one embodiment, the control device further controls the transfer chamber to move linearly in the direction in which the transfer gate valve is located, so as to bring the transfer gate valve into contact with the gate valves of other chambers, thereby opening the transfer chamber and the corresponding other chambers under the same pressure.

[0019] In one embodiment, the epitaxial wafer stripping device further includes:

[0020] The separation chamber is located within the peripheral chamber and between the stripping chamber and the cleaning and drying chamber. It has a separation gate valve on the side facing the transfer chamber. When the separation gate valve is closed, it isolates the interior of the separation chamber from the exterior. The separation chamber is used to separate the epitaxial wafer from the substrate.

[0021] In one embodiment, the epitaxial wafer stripping device further includes:

[0022] The loading and unloading cavity is located inside the peripheral cavity and has a loading and unloading gate valve on the side facing the transfer cavity. When the loading and unloading gate valve is closed, it isolates the interior of the loading and unloading cavity from the exterior. The loading and unloading cavity is used to load and unload epitaxial wafers.

[0023] In one embodiment, the transfer chamber, the loading and unloading chamber, the stripping chamber, the separation chamber, the cleaning and drying chamber, the heating chamber, the deposition chamber, and the peripheral chamber are connected to different vacuum devices within the vacuum system.

[0024] The aforementioned epitaxial wafer stripping apparatus includes a heating chamber. Heating the epitaxial wafer in the heating chamber further removes residual moisture from its surface, effectively preventing residual moisture from affecting the subsequent deposition process in the deposition chamber. Furthermore, heating the epitaxial wafer in the heating chamber before transporting it to the deposition chamber for film deposition further reduces crystallization time, thereby improving the crystallization quality of the deposited film.

[0025] Therefore, the performance of the device formed from the epitaxial wafer after being processed by the epitaxial wafer stripping device according to the embodiments of this application can be effectively improved.

[0026] Meanwhile, the epitaxial wafer is in a vacuum environment during transport between different chambers, which can reduce external contamination such as C, O and other donor impurities in the air during the stripping process, thereby further improving the performance of the final device. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of an epitaxial wafer stripping device provided in one embodiment;

[0029] Figure 2 This is a schematic diagram of a laser ablation device provided in one embodiment;

[0030] Figure 3 This is a schematic diagram of a molding mask provided in one embodiment;

[0031] Figure 4 This is a schematic diagram of the epitaxial wafer stripping device provided in another embodiment. Detailed Implementation

[0032] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0034] It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, regions, layers, doping types, and / or portions, these elements, components, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, doping type, or portion from another element, component, region, layer, doping type, or portion. Therefore, without departing from the teachings of this application, the first element, component, region, layer, doping type, or portion discussed below may be referred to as a second element, component, region, layer, or portion.

[0035] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0036] In one embodiment, see Figure 1 An epitaxial wafer stripping apparatus is provided, which includes multiple chambers, including at least a stripping chamber 100, a cleaning and drying chamber 200, a heating chamber 300, and a deposition chamber 400.

[0037] The release chamber 100 is used to separate the substrate from the epitaxial wafer. Before separation, the epitaxial wafer can be heterogeneously grown on the substrate. As an example, the substrate of the heterogeneously grown epitaxial wafer can be a sapphire substrate. The epitaxial wafer can be a gallium nitride epitaxial wafer.

[0038] The lift-off cavity 100 can be equipped with a lift-off stage for placing the substrate with the epitaxial wafer grown on it. During lift-off, an ultraviolet laser of a suitable wavelength can be selected to irradiate from one side of the substrate. Simultaneously, the lift-off stage can be equipped with a heating device to heat the substrate at the same time. At this point, the epitaxial wafer at the interface decomposes. In laser lift-off technology, a laser with energy less than that of the substrate material and a band gap larger than that of the epitaxial wafer material is used to penetrate the substrate and reach the interface between the substrate and the epitaxial wafer. The epitaxial wafer will then decompose under certain pressure and temperature. When the epitaxial wafer is a gallium nitride epitaxial wafer, the reaction is as follows:

[0039]

[0040] Gallium nitride (GaN) decomposes at 900°C under one atmosphere. If the equilibrium pressure is lower than one atmosphere, the decomposition temperature of GaN decreases, and the required laser threshold power density also decreases. Therefore, a vacuum system can be used to evacuate the stripping chamber 100 during the stripping process. After evacuation, the vacuum level in the stripping chamber 100 can reach as low as 10⁻⁵ Pa. Under this vacuum level, the decomposition temperature of GaN decreases to 688 K, enabling stripping at a lower temperature and thus achieving rapid, low-power laser stripping.

[0041] The stripping stage for the epitaxial wafer can move horizontally under the control of a controller. When the laser beam cannot completely cover the epitaxial wafer, the stage can be moved back and forth or left and right, and the epitaxial wafer moves along with the stage on the work platform. This ensures that the laser beam evenly irradiates all areas of the epitaxial wafer. Specifically, the movement trajectory and speed of the stage can be controlled, such as moving the stage at a step speed of 1 mm / s along the left and right or back and forth directions to achieve comprehensive stripping by the laser beam. During the stripping process, the vacuum system of the stripping chamber 100 can be kept on to remove impurity gases (such as nitrogen gas formed by the decomposition of gallium nitride) generated during the stripping process, preventing contamination of other chambers.

[0042] The cleaning and drying chamber 200 is used to clean and dry the epitaxial wafer after it has been peeled off.

[0043] The cleaning and drying chamber 200 may be equipped with a cleaning worktable, a cleaning device, a rotating robotic arm, and a blowing device. The cleaning worktable is used to place the epitaxial wafers. The cleaning device is used to rinse the epitaxial wafers. The rotating robotic arm is used to grip and rotate the epitaxial wafers. The blowing device is used to blow away moisture from the surface of the epitaxial wafers.

[0044] When cleaning and drying epitaxial wafers, the wafers are first placed on a cleaning table with the surface adjacent to the growth substrate facing upwards. Then, this surface of the epitaxial wafer is rinsed using a cleaning device. Specifically, deionized water can be used to rinse the epitaxial wafer. Afterwards, a purging device is used to purge the epitaxial wafer. Specifically, nitrogen gas can be used to blow the epitaxial wafer dry.

[0045] The epitaxial wafer is then flipped using a robotic arm so that the surface away from its growth substrate is facing upwards. This surface is then rinsed sequentially using a cleaning device. Afterwards, the surface away from its growth substrate is dried by purging with nitrogen gas. Following purging, the surface away from its growth substrate is now facing upwards for subsequent deposition.

[0046] Since there may be certain defects or roughness at the laser lift-off interface, when forming a functional layer on the epitaxial layer, using the surface away from the lift-off interface as the top surface for subsequent deposition processes can effectively improve the performance of the final device.

[0047] The heating chamber 300 is equipped with a heating device, which is used to heat the cleaned and dried epitaxial wafer to remove moisture and reduce the deposition time of the epitaxial wafer.

[0048] Specifically, the heating chamber 300 can be located between the cleaning and drying chamber 200 and the deposition chamber 400, and can be equipped with multiple heating worktables. These worktables can be arranged vertically from top to bottom, and each worktable can hold one epitaxial wafer, allowing for the temporary storage of multiple epitaxial wafers. The heating device can independently heat each worktable, thus heating the epitaxial wafers placed on each worktable as needed.

[0049] Deposition chamber 400 is used for deposition based on heated epitaxial wafers.

[0050] The deposition chamber 400 may be equipped with a pressure detection device and a gas detection device. The second pressure detection device and the second gas detection device are used to detect the type and pressure of the gas in the deposition chamber 400, and then to regulate the gas parameters in the deposition chamber 400 to achieve deposition.

[0051] The number of deposition chambers 400 can be one or more.

[0052] Specifically, the deposition methods in each deposition chamber 400 may include metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and atomic layer deposition (ALD). Depending on the type of device formed and the layer structure deposited, a robotic arm 510 can be used to control the transport of the target substrate within different deposition chambers 400.

[0053] The deposition chamber 400 can be equipped with a growth stage, and the chamber can have several gas inlets. When the target substrate is delivered into the deposition chamber, a vacuum can be drawn according to the device type. Then, different gases are introduced through the gas inlets according to the gases used in epitaxial growth.

[0054] The deposition chamber 400 may also include multiple infrared pyrometry detectors, which can be used to measure the temperature of the center and edge of the target substrate during epitaxial growth, as well as the temperature of the sidewalls of the deposition chamber 400.

[0055] In this embodiment, a heating chamber 300 is provided. Heating the epitaxial wafer in the heating chamber 300 further removes residual moisture from the surface of the epitaxial wafer, effectively preventing residual moisture from affecting the subsequent deposition process in the deposition chamber 400. Moreover, in the deposition step, the deposition of the gallium nitride layer requires a temperature of 900-1200 degrees Celsius. Preheating the epitaxial wafer will not affect the subsequent deposition. After being heated by the heating device in the heating chamber 300, the epitaxial wafer is transported to the deposition chamber 400 for film deposition. Due to the higher surface temperature of the preheated epitaxial wafer, the crystallization time can be further reduced, thereby improving the crystal quality of the deposited film.

[0056] Therefore, the performance of the device formed from the epitaxial wafer processed by the epitaxial wafer stripping device in this embodiment can be effectively improved.

[0057] Meanwhile, in the epitaxial wafer stripping device of this embodiment, the epitaxial wafer is in a vacuum environment when it is transferred between different chambers, which can reduce external contamination such as C, O and other donor impurities in the air during the stripping process, thereby further improving the performance of the final device.

[0058] In one embodiment, a laser ablation device is provided within the ablation cavity 100. See also... Figure 2 as well as Figure 3 The laser stripping device includes a laser emitting unit 210 and a forming mask 220.

[0059] The laser emitting unit 210 is used to emit laser light. Specifically, the laser emitting unit 210 may include, but is not limited to, an excimer laser unit with the desired wavelength, a diode-excited solid-state laser unit, or an ultrafast laser unit with the desired wavelength.

[0060] The molding mask 220 includes multiple light-transmitting holes 220a. As an example, the molding mask 220 can be divided into several rectangular units, each of which is a light-transmitting hole 220a. Each light-transmitting hole 220a is equipped with a light valve (not shown), which controls whether light passes through the hole. Specifically, the light valve may include a grating light valve or a liquid crystal light valve.

[0061] Traditional forming masks can only process epitaxial wafers of specific sizes. In existing technologies, when the size of the epitaxial wafer changes, a forming mask of a corresponding size needs to be replaced. However, this embodiment includes multiple light-transmitting holes 220a equipped with light valves in the forming mask 220. By opening and closing the light valves of each light-transmitting hole 220a, the position and size of the final light-transmitting area of ​​the forming mask 220 can be controlled. Therefore, the same forming mask can process epitaxial wafers of various sizes, thereby improving the versatility of the forming mask.

[0062] In one embodiment, the laser stripping apparatus further includes a mask control element (not shown) that controls the opening and closing of each optical valve according to the size of the epitaxial wafer.

[0063] Specifically, when the epitaxial wafer is small, the mask control element can control the opening of light valves through fewer light-transmitting holes. Conversely, when the epitaxial wafer is large, the mask control element can control the opening of light valves through more light-transmitting holes. Specifically, in use, the rectangular unit containing the edge of the epitaxial wafer is used as the boundary unit. The boundary unit and the light valves within it are opened to peel off the epitaxial wafer according to its dimensions.

[0064] Furthermore, the laser lift-off apparatus may also include beam-shaping optics (e.g., mirrors, lenses, etc.). The beam-shaping optics can alter the shape and / or size of the forming beam behind the forming mask 220. During laser lift-off, the substrate is on top and the epitaxial wafer is below; the laser beam is incident from one side of the substrate at the interface between the substrate and the epitaxial wafer.

[0065] In one embodiment, the heating cavity 300 is further provided with a temperature detection device, which is used to detect the temperature of the epitaxial wafer.

[0066] Specifically, when multiple heating stages are provided within the heating chamber 300, the temperature detection device may include multiple temperature detection units. Each temperature detection unit is responsible for detecting the temperature of one heating stage. In this case, the temperature of the epitaxial wafers placed on each heating stage can be detected.

[0067] Of course, a heating worktable can also be installed inside the heating chamber 300. In this case, the temperature detection device can also include a temperature detection unit.

[0068] By setting the temperature detection device, the heating temperature of the epitaxial wafer can be precisely controlled. Specifically, the epitaxial wafer can be heated to a preset temperature. The preset temperature can be higher than the vaporization temperature of water but lower than the subsequent deposition process temperature. This further removes residual moisture from the surface of the epitaxial wafer, and transporting the heated epitaxial wafer to the deposition equipment for deposition will not affect subsequent deposition. Furthermore, the higher surface temperature of the heated epitaxial wafer further reduces crystallization time and improves deposition quality.

[0069] As an example, when the epitaxial wafer is a gallium nitride (GaN) epitaxial wafer, the wafer, after being heated in the heating chamber, can be placed in the deposition chamber for homogeneous epitaxial deposition. The GaN layer deposition temperature needs to be between 900℃ and 1200℃. At this point, a preset temperature can be set to 400℃ to 500℃. Further, a preset temperature can be set to 200℃ to 300℃.

[0070] In one embodiment, the heating device is electrically connected to a temperature detection device. In this case, the heating device can automatically heat the epitaxial wafer based on the detection results of the temperature detection device.

[0071] Specifically, for example, when the temperature detection device detects that the temperature of the epitaxial wafer is lower than a preset temperature, the heating device can heat the corresponding epitaxial wafer. When the temperature detection device detects that the temperature of the epitaxial wafer has reached the preset temperature, the heating device can stop heating the corresponding epitaxial wafer.

[0072] In one embodiment, see Figure 4 The epitaxial wafer stripping device also includes a transfer cavity 500 and a control device 600.

[0073] The transfer chamber 500 is equipped with a robotic arm 510. The transfer chamber 500 is surrounded by other chambers and has a transfer gate valve 520, which isolates the interior of the transfer chamber 500 from the outside when closed. Furthermore, the transfer chamber 500 can be connected to a vacuum system, thereby providing a vacuum environment for the interior of the chamber.

[0074] Specifically, the robotic arm 510 includes a robotic arm 511 and a wafer pickup interface 512. The wafer pickup interface 512 picks up wafers via vacuum adsorption and transports them to other chambers via the robotic arm 511. Meanwhile, the transfer chamber 500 has a transfer gate valve 520. The transfer gate valve 520 can close the transfer chamber 500. The transfer chamber 500 can be connected to a vacuum system, thereby ensuring a closed vacuum environment within the transfer chamber 500.

[0075] Meanwhile, the stripping chamber 100 has a stripping gate valve 110 on the side facing the transfer chamber 500. When the stripping gate valve 110 is closed, it isolates the interior of the transfer chamber 500 from the outside. Furthermore, the stripping chamber 100 can be connected to a vacuum system, thereby allowing the stripping chamber 100 to be in a closed vacuum environment.

[0076] Meanwhile, the cleaning and drying chamber 200 has a cleaning gate valve 210 on the side facing the transfer chamber 500. When the cleaning gate valve 210 is closed, it isolates the interior of the cleaning and drying chamber 200 from the outside. Furthermore, the cleaning and drying chamber 200 can be connected to a vacuum system, thereby allowing the cleaning and drying chamber 200 to be in a closed vacuum environment.

[0077] Meanwhile, the heating chamber 300 has a heating gate valve 310 on the side facing the transfer chamber 500. When the heating gate valve 310 is closed, it isolates the interior of the heating chamber 300 from the outside. Furthermore, the heating chamber 300 can be connected to a vacuum system, thereby allowing the heating chamber 300 to be in a closed vacuum environment.

[0078] The deposition chamber 400 has a deposition gate valve 410 on the side facing the transfer chamber 500. When the deposition gate valve 410 is closed, it isolates the interior of the deposition chamber 400 from the outside, thereby protecting the deposition chamber 400 from contamination by other chambers. The heating chamber 300 can be located between the deposition chamber 400 and the cleaning and drying chamber 200, thereby facilitating the transfer of epitaxial wafers to it.

[0079] The control device 600 is used to control the rotation of the transfer cavity 500. Under the control of the control device 600, the transfer cavity 500 can rotate between the stripping cavity 100, the cleaning and drying cavity 200 and the heating cavity 300, thereby enabling the transfer of wafers between the stripping cavity 100, the cleaning and drying cavity 200 and the heating cavity 300.

[0080] In this embodiment, the stripping chamber 100, cleaning and drying chamber 200, heating chamber 300, and deposition chamber 400 are all connected to a vacuum system, ensuring that each process chamber is under vacuum, thereby preventing contamination of the epitaxial wafer during each stripping process. Simultaneously, this embodiment also includes a transfer chamber 500. The transfer chamber 500 is also connected to a vacuum system, preventing contamination of the epitaxial wafer during transfer. Therefore, this embodiment effectively reduces external contamination such as C, O, and other donor impurities in the air during the stripping process.

[0081] Furthermore, the transfer chamber 500 in this embodiment has a transfer gate valve 520. When the transfer gate valve 520 is closed, it isolates the interior of the transfer chamber 500 from the exterior, thus making the transfer chamber 500 independent of other chambers. This allows the transfer chamber 500 to be unaffected by other chambers. For example, the size of the transfer chamber 500 is not affected by other chambers, allowing for flexible configuration to adapt to specific needs. Specifically, the transfer chamber 500 can be configured as a relatively small chamber, facilitating evacuation to a higher vacuum level for better protection during epitaxial wafer transfer and preventing contamination. Simultaneously, the independence of the transfer chamber 500 from other chambers reduces the difficulty of chamber design, fabrication, and post-use maintenance.

[0082] Furthermore, the transfer chamber 500 in this embodiment can rotate under the control of the control device, so that the same transfer gate valve 520 can be aligned with different process chambers by rotating the transfer chamber 500. This makes it possible to set only one transfer gate valve 520 in the transfer chamber 500, thereby simplifying the structure of the transfer chamber 500 and reducing the manufacturing cost of the transfer chamber 500.

[0083] Specifically, a vacuum system can include multiple vacuum pumping devices. Different chambers can have independent vacuum pumping devices, allowing for flexible vacuuming of each chamber as needed. Of course, different chambers can also share a single vacuum pumping device; this is not a limitation.

[0084] Furthermore, there can be multiple deposition chambers 400. When there are multiple deposition chambers 400, each deposition chamber 400 can be equipped with a deposition gate valve 810, and each deposition chamber 400 can be connected to a vacuum system. The vacuum systems of each deposition chamber 400 can be independent of each other.

[0085] In one embodiment, see Figure 4 The epitaxial wafer stripping apparatus also includes a peripheral cavity 700. The transfer cavity 500, stripping cavity 100, cleaning and drying cavity 200, heating cavity 300, and deposition cavity 400 are all located within the peripheral cavity 700. The peripheral cavity 700 is also connected to a vacuum system.

[0086] The peripheral cavity 700 allows the entire epitaxial wafer stripping device to be in a closed vacuum environment, thereby effectively preventing the epitaxial wafer from being contaminated during the etching process.

[0087] It is understood that the peripheral cavity 700 has an external cavity inlet / outlet portion (not shown in the figure) for the epitaxial wafer to enter and exit.

[0088] Meanwhile, as an example, the control device 600 can be located outside the peripheral cavity 700. This facilitates operation and control by the operator.

[0089] Of course, the configuration of the epitaxial wafer stripping apparatus is not limited to this. For example, in some embodiments, the epitaxial wafer stripping apparatus also includes an inner cavity. Other chambers besides the transfer chamber 500 (such as the stripping chamber 100, the cleaning and drying chamber 200, the heating chamber 300, and the deposition chamber 400, etc.) surround and form a closed inner cavity. The inner cavity is also connected to a vacuum system, in which case the transfer chamber 500 can be located within the inner cavity. Alternatively, in some embodiments, the epitaxial wafer stripping apparatus may also have both an outer cavity and an inner cavity, etc., and there is no limitation on this.

[0090] In one embodiment, the control device 600 also controls the transfer chamber 500 to move in the direction where it is provided with the transfer gate valve 520, specifically in a linear motion, so as to bring the transfer gate valve into contact with the gate valves of other chambers, thereby opening the transfer chamber and the corresponding other chambers under the same pressure.

[0091] During the transfer of the epitaxial wafer in the chamber corresponding to the transfer gate valve 520 (such as the peeling chamber 100, the cleaning and drying chamber 200, or the heating chamber 300), the transfer chamber 500 can move towards the corresponding chamber and contact its gate valve. Then, both chambers are evacuated to a similar pressure, thereby simultaneously opening the gate valves of both chambers. The epitaxial wafer is then transferred via the robotic arm 510. After the epitaxial wafer transfer is complete, the gate valves of both chambers are simultaneously closed. Afterwards, the transfer chamber 500 can move away from the chamber under the control of the control device 600, returning to its origin. Then, the control device 600 controls the rotation direction of the transfer chamber 500 to allow the transfer gate valve 520 to transfer the epitaxial wafer between other chambers. During the epitaxial wafer transfer process, to save time, the relevant chambers can be evacuated simultaneously. For example, during the process of removing the epitaxial wafer from the peeling chamber, the peeling chamber and the transfer chamber can be evacuated simultaneously.

[0092] In this embodiment, the transfer cavity 500 can be conveniently transferred to other cavities. Of course, in other embodiments, the control device may not control the transfer cavity 500 to move in the direction where the transfer gate valve 520 is provided.

[0093] For example, in other embodiments, when a peripheral cavity is provided, when transferring the epitaxial wafer between the transfer cavity 500 and other cavities, the two cavities and the peripheral cavity 700 surrounding them can be evacuated simultaneously, so that the pressure of the two cavities is equivalent to that of the peripheral cavity, thereby opening the gate valves of the two cavities to transfer the epitaxial wafer.

[0094] In this embodiment, since the control device 600 also controls the transfer cavity 500 to move linearly in the direction where the transfer gate valve 520 is provided, the vacuum requirement of the peripheral cavity 700 is greatly reduced.

[0095] In some embodiments, the control module of the control device 600 can also simultaneously control the movement of the robotic arm 510 and the opening and closing of the gate valves in each chamber, etc.

[0096] In one embodiment, see Figure 4 The epitaxial wafer stripping apparatus also includes a separation chamber 800. The separation chamber 800 is located within the peripheral chamber and between the stripping chamber 100 and the cleaning and drying chamber 200, and is used to separate the epitaxial wafer from the substrate.

[0097] After the substrate and epitaxial wafer are separated by laser within the separation cavity 100, they may still be connected by substances formed from the decomposition of the epitaxial wafer. For example, when the epitaxial wafer is a gallium nitride epitaxial wafer, metallic gallium will still be present between the substrate and the epitaxial wafer. In this case, a further step of separating the substrate and the epitaxial wafer is required.

[0098] In this embodiment, a separation cavity 800 is provided so that the substrate and the epitaxial wafer can be completely separated.

[0099] As an example, the separation chamber 800 may be equipped with an acid pickling device. The acid pickling device may contain an acid pickling solution, which reacts with the substances formed by the decomposition of the epitaxial wafer, thereby separating the substrate from the epitaxial wafer.

[0100] Specifically, when the epitaxial wafer is a gallium nitride (GaN) epitaxial wafer and the substrate is a sapphire substrate, the epitaxial wafer connected to the substrate can be placed in an acid pickling solution for acid pickling. A 20%-50% hydrochloric acid solution can be used for pickling. Immersing the epitaxial wafer in dilute hydrochloric acid separates the GaN epitaxial wafer from the substrate.

[0101] Meanwhile, the separation chamber 800 has a separation gate valve 810 on the side facing the transfer chamber 500. When the separation gate valve 810 is closed, it isolates the interior of the separation chamber 800 from the outside, thus making the separation chamber 800 independent of other chambers. At this time, the separation chamber 800 can also be connected to a vacuum system, so that separation can be carried out in a vacuum environment, thereby preventing the epitaxial wafer from being contaminated by other gaseous impurities during the separation process.

[0102] In one embodiment, see Figure 4 The epitaxial wafer stripping device also includes a loading and unloading cavity 900. The loading and unloading cavity 900 is used to load and unload the epitaxial wafer.

[0103] Specifically, the loading / unloading cavity 900 can also be connected to a vacuum system, which can also be located within the peripheral cavity 700. Furthermore, the loading / unloading cavity 80 may include a loading / unloading section 910.

[0104] When the epitaxial wafer is transferred from the outside to the epitaxial wafer stripping device, the loading and unloading section 910 of the loading and unloading cavity 900 can be opened first. Then, the epitaxial wafer is placed inside the loading and unloading cavity 900. Afterward, the loading and unloading section 910 is closed. An epitaxial wafer placement device (not shown) can be installed inside the loading and unloading cavity 900. The epitaxial wafer placement device can include multiple epitaxial wafer placement stages, which can be arranged vertically from top to bottom. Each epitaxial wafer placement stage can hold one epitaxial wafer.

[0105] Meanwhile, the loading / unloading chamber 900 has a loading / unloading gate valve 920 on the side facing the transfer chamber 500. When the loading / unloading gate valve 920 is closed, it isolates the interior of the loading / unloading chamber 900 from the outside. The loading / unloading chamber 900 is used to load and unload epitaxial wafers. At this time, the loading / unloading chamber 900 can transfer epitaxial wafers between itself and the transfer chamber 500 through the loading / unloading gate valve 920.

[0106] The loading and unloading section 910 is arranged opposite to the loading and unloading gate valve 920, so that the epitaxial wafer can be conveniently transferred to the outside and transferred to the transfer chamber 500 on opposite sides of the loading and unloading chamber 900.

[0107] Specifically, the loading / unloading section 910 can be configured as a gate valve or in other forms (such as a window), and there is no limitation on this. Alternatively, the loading / unloading section 910 may not be provided. In this case, the loading / unloading cavity 900 can be configured to rotate, thereby realizing the transfer of the epitaxial sheet between the loading / unloading cavity 900 and the outside, and the transfer of the epitaxial sheet between the loading / unloading cavity 900 and the transfer cavity 500, respectively, by having the loading / unloading gate valve 920 in different positions.

[0108] Meanwhile, the loading and unloading chamber can be connected to a nitrogen inlet pipeline, which can then inject nitrogen into the loading and unloading chamber 900°. Using nitrogen to clean the epitaxial wafer can remove impurities that have adhered to the epitaxial wafer during transportation; the cleaning time can be 30 seconds to 5 minutes.

[0109] After deposition is completed on the epitaxial wafer, the deposited product can be removed from the deposition chamber 400 and transferred to the loading / unloading chamber 900. The loading / unloading gate valve 920 in the loading / unloading chamber 900 is closed. Then, nitrogen gas is introduced into the loading / unloading chamber 900 to ensure that the pressure is consistent with the external pressure. At this point, the loading / unloading section 910 on the other side of the loading / unloading chamber 900 is opened to transport the processed product out.

[0110] In one embodiment, the transfer chamber 500, loading and unloading chamber 900, stripping chamber 100, separation chamber 800, cleaning and drying chamber 200, heating chamber 300, deposition chamber 400, and peripheral chamber 600 are connected to different vacuum devices within the vacuum system, thereby allowing for flexible control of the vacuum level in each chamber.

[0111] Further, please refer to Figure 4 The conveying chamber 500, loading and unloading chamber 900, stripping chamber 100, separation chamber 800, cleaning and drying chamber 200, heating chamber 300 and sedimentation chamber 400 can all be located within the outer chamber 700.

[0112] Specifically, the transfer chamber 500 can be located in the middle area. The loading and unloading chamber 900, the stripping chamber 100, the separation chamber 800, the cleaning and drying chamber 200, the heating chamber 300, and the deposition chamber 400 can surround the transfer chamber 500.

[0113] At this point, the loading / unloading chamber 900, peeling chamber 100, separation chamber 800, washing / drying chamber 200, heating chamber 300, and deposition chamber 400 can be positioned between the vertices of a regular polygon, while the transfer chamber 500 is located at the center of the polygon. Alternatively, the loading / unloading chamber 900, peeling chamber 100, separation chamber 800, washing / drying chamber 200, heating chamber 300, and deposition chamber 400 can be positioned at different locations on the same circle, with the transfer chamber 500 located at the center of that circle. In this case, it can be ensured that the robotic arm 510 within the transfer chamber 500 can transport samples at equal distances. This allows for rapid and precise sample transfer.

[0114] In the description of this specification, references to terms such as "one embodiment," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0115] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An epitaxial wafer stripping device, characterized in that, It includes multiple chambers, and the multiple chambers include at least: a transfer chamber, a stripping chamber, a washing and drying chamber, a heating chamber, and a deposition chamber; The epitaxial wafer is transported in a vacuum environment when it is moved between different chambers; The stripping chamber is used to strip the substrate from the epitaxial wafer, and the cleaning and drying chamber is used to clean and dry the stripped epitaxial wafer. The heating chamber is equipped with a heating device, which is used to heat the cleaned and dried epitaxial wafer to remove moisture and reduce the deposition time of the epitaxial wafer. The deposition chamber performs deposition based on the heated epitaxial wafer. The epitaxial wafer is transferred between different chambers based on the transfer cavity, and the transfer is carried out in a vacuum environment; the transfer cavity has a transfer gate valve, which makes the transfer cavity independent of other chambers; other chambers outside the transfer cavity surround and form a closed inner cavity, and the transfer cavity is located in the inner cavity; wherein, by rotating the transfer cavity, the same transfer gate valve is aligned with different chambers, and the transfer gate valve of the transfer cavity and the gate valve independently set in the aligned chamber are both in the open state, so as to transfer the epitaxial wafer.

2. The epitaxial wafer stripping apparatus according to claim 1, characterized in that, The stripping cavity is equipped with a laser stripping device, which includes: A laser emitting unit is used to emit laser light. A molding mask includes multiple light-transmitting holes, each of which is equipped with a light valve, which is used to control whether the light-transmitting hole it is located in transmits light.

3. The epitaxial wafer stripping apparatus according to claim 2, characterized in that, The laser ablation device also includes: A mask control element controls the opening and closing of each optical valve according to the size of the epitaxial wafer.

4. The epitaxial wafer stripping apparatus according to claim 1, characterized in that, The heating chamber is also equipped with a temperature detection device, which is used to detect the temperature of the epitaxial wafer. The heating device is electrically connected to the temperature detection device and is used to heat the epitaxial wafer according to the detection result of the temperature detection device.

5. The epitaxial wafer stripping apparatus according to claim 1, characterized in that, The epitaxial wafer stripping device also includes a control device; The transfer chamber is equipped with a robotic arm and is surrounded by other chambers. When the transfer gate valve is closed, it isolates the interior of the transfer chamber from the outside. The stripping chamber has a stripping gate valve on the side facing the transfer chamber, which isolates the interior of the transfer chamber from the outside when closed. The cleaning and drying chamber has a cleaning gate valve on the side facing the transfer chamber, which isolates the interior of the cleaning and drying chamber from the outside when closed. The heating chamber has a heating gate valve on the side facing the transfer chamber, which isolates the interior of the heating chamber from the outside when closed. The deposition chamber has a deposition gate valve on the side facing the transfer chamber, which isolates the interior of the deposition chamber from the outside when closed. The transfer chamber, the stripping chamber, the cleaning and drying chamber, the heating chamber, and the deposition chamber are all connected to a vacuum system to allow the epitaxial wafer to be transferred between the transfer chamber and other chambers under vacuum conditions. A control device is used to control the rotation of the conveying cavity.

6. The epitaxial wafer stripping apparatus according to claim 5, characterized in that, The epitaxial wafer stripping device also includes a peripheral cavity, in which the conveying cavity, the stripping cavity, the cleaning and drying cavity, the heating cavity, and the deposition cavity are all located. The peripheral cavity is also connected to a vacuum system.

7. The epitaxial wafer stripping apparatus according to claim 5, characterized in that, The control device also controls the conveying chamber to move in the direction in which the conveying gate valve is located, so as to bring the conveying gate valve into contact with the gate valves of other chambers, thereby opening the conveying chamber and the corresponding other chambers under the same pressure.

8. The epitaxial wafer stripping apparatus according to claim 6, characterized in that, The epitaxial wafer stripping device further includes: The separation chamber is located within the peripheral chamber and between the stripping chamber and the cleaning and drying chamber. It has a separation gate valve on the side facing the transfer chamber. When the separation gate valve is closed, it isolates the interior of the separation chamber from the exterior. The separation chamber is used to separate the epitaxial wafer from the substrate.

9. The epitaxial wafer stripping apparatus according to claim 8, characterized in that, The epitaxial wafer stripping device further includes: The loading and unloading cavity is located inside the peripheral cavity and has a loading and unloading gate valve on the side facing the transfer cavity. When the loading and unloading gate valve is closed, it isolates the interior of the loading and unloading cavity from the exterior. The loading and unloading cavity is used to load and unload epitaxial wafers.

10. The epitaxial wafer stripping apparatus according to claim 9, characterized in that, The transfer chamber, the loading and unloading chamber, the stripping chamber, the separation chamber, the cleaning and drying chamber, the heating chamber, the deposition chamber, and the peripheral chamber are connected to different vacuum devices within the vacuum system.

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