Epitaxial wafer resistance measurement preprocessing device

Abstract

The present invention relates to the technical field of epitaxial wafer production equipment, and discloses an epitaxial wafer resistance value measurement pretreatment device, including a main body, the top of which is sequentially provided with a primary cleaning pool, a secondary cleaning pool, and a tertiary cleaning pool, and also includes: a placement rack, the placement rack includes: a frame body; a placement slot; a fluid channel; a cleaning roller, which is in the shape of a hollow circular tube, the cleaning roller is rotatably arranged on the frame body, the two ends of the cleaning roller are connected to the fluid channel, and two cleaning rollers are mirror-imaged and arranged on both sides of the lower part of the frame body; a paddle, which is fixedly arranged at the end of the cleaning roller; a spray hole, which is evenly opened in the middle of the cleaning roller; a pressing component, so that the epitaxial wafer is pressed against the cleaning roller; a pump, which is arranged on one side of the three-stage cleaning pool. The present invention can solve or at least alleviate the problem that the existing epitaxial wafer surface pretreatment device is easy to cause scratches on the surface of the epitaxial wafer and a large number of fine particles attached, and provides an epitaxial wafer resistance value measurement pretreatment device.

Description

Technical Field

[0001] The invention relates to the technical field of epitaxial wafer production equipment, and in particular to an epitaxial wafer resistance value measurement preprocessing device. Background Art

[0002] Epitaxial growth is a very important link in the semiconductor industry chain, and the crystal quality of epitaxial wafers is one of the key factors affecting device performance. As a key material in semiconductor technology, the surface quality of epitaxial wafers is directly related to the performance and stability of subsequent devices. Therefore, cleaning the surface of epitaxial wafers is crucial.

[0003] For example, a device and method for pretreating the surface of an epitaxial wafer with publication number CN118788671B comprises a main body, a primary cleaning pool, a secondary cleaning pool and a tertiary cleaning pool are sequentially provided on the top of the main body, and further comprises: a placement rack, which can accommodate and place a plurality of epitaxial wafers and sequentially place the epitaxial wafers into the primary cleaning pool, the secondary cleaning pool and the tertiary cleaning pool for cleaning through a mechanical arm. The present invention also discloses a method for pretreating the surface of an epitaxial wafer, comprising the following steps: primary cleaning, secondary cleaning, tertiary cleaning and drying. The present invention avoids the problem of the epitaxial wafer floating during the soaking process by driving a pressure plate to press on the circumference of the epitaxial wafer under the action of buoyancy by a float, and by placing the spray hole close to the circumference of the corresponding epitaxial wafer, deionized water is sprayed on both sides of the epitaxial wafer in an inclined manner through the first inclined hole and the second inclined hole, thereby increasing the spray coverage of the epitaxial wafer and improving the cleaning effect of the epitaxial wafer.

[0004] However, although this solution avoids the epitaxial wafers in the placement rack from floating up during immersion, it is sprayed after the water is released. During spraying, the spraying water flow directly impacts the epitaxial wafer. When the impact force of the spraying water flow is small, it is not easy to remove the attachments on the surface of the epitaxial wafer. When the impact force of the spraying water flow is large, scratches will appear on the surface of the epitaxial wafer, resulting in a large surface roughness of the epitaxial wafer.

[0005] Moreover, in this scheme, the epitaxial wafer is driven to rotate in the placement rack by the transmission shaft, and the transmission shaft passes through the main body. To ensure the sealing of the tertiary cleaning tank, the transmission shaft needs to fit tightly with the main body. When the transmission shaft rotates, certain fine particles will be generated. These fine particles will increase the particle level of the pure water in the tertiary cleaning tank, and some of the fine particles will adhere to the epitaxial wafer.

[0006] At the same time, during drying, even if the air guide tube is repeatedly moved horizontally to make the blowing range more comprehensive, it is still impossible to quickly remove water from the epitaxial wafer, which is prone to insufficient drying. The water on the surface of the epitaxial wafer forms water droplets, which react with silicon dioxide formed by oxidation of silicon in water to form stable metasilicic acid. These metasilicic acids appear as granular water marks on the surface of the silicon epitaxial wafer after cleaning. Water marks will affect the integrity of etching, cause regional chip failure, and cause final yield loss. Summary of the invention

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art, solve or at least alleviate the problem that the existing epitaxial wafer surface pretreatment device easily causes scratches on the epitaxial wafer surface and a large number of fine particles attached, and provide an epitaxial wafer resistance value measurement pretreatment device.

[0008] To achieve the above object, the present invention provides the following technical solution: an epitaxial wafer resistance value measurement pretreatment device, comprising a main body, a primary cleaning pool, a secondary cleaning pool and a tertiary cleaning pool are sequentially opened on the top of the main body, and further comprising:

[0009] A placement rack is used to store and place multiple epitaxial wafers, and the placement rack is sequentially placed into a primary cleaning tank, a secondary cleaning tank, and a tertiary cleaning tank for cleaning by a robotic arm. The placement rack includes:

[0010] Frame;

[0011] A placement slot is evenly arranged in the middle of the frame;

[0012] A fluid channel is opened inside the frame, with one end penetrating to the bottom end of the frame and the other end extending upward to the top end of the frame;

[0013] A cleaning roller, which is in the shape of a hollow circular tube, is rotatably arranged on the frame, both ends of the cleaning roller are connected to the fluid channel, and two cleaning rollers are arranged on both sides of the lower part of the frame in a mirror-image relationship, and the cleaning rollers support the bottom of the epitaxial wafer placed in the frame;

[0014] A paddle is fixedly arranged at the end of the cleaning roller. When the fluid in the fluid channel enters the cleaning roller, the cleaning roller is driven to rotate through the paddle. When the cleaning roller rotates, the epitaxial wafer in the frame is driven to rotate;

[0015] Spray holes are evenly arranged in the middle of the cleaning roller, the spray holes are staggered with the placement grooves, and the spray direction of the spray holes is toward the side of the epitaxial wafer in the corresponding placement groove;

[0016] The clamping assembly is rotatably arranged on both sides of the top of the placement rack. The clamping assembly restricts the epitaxial wafer inside the placement rack so that the epitaxial wafer abuts against the cleaning roller.

[0017] In order to further realize the present invention, the following technical solutions may be preferably selected:

[0018] Preferably, it also includes a flow supply channel, which is arranged in the main body and located below the three-stage cleaning tank. When the placement rack is located on the bottom surface of the three-stage cleaning tank, the flow supply channel is connected with the fluid channel;

[0019] A diversion channel is arranged in the main body and located on the side of the third-level cleaning tank;

[0020] A pump is arranged on one side of the three-stage cleaning tank, the outlet end of the pump is connected to the flow supply channel, the inlet end of the pump is connected to the three-stage cleaning tank through the guide channel, and the pump supplies the liquid in the three-stage cleaning tank to the cleaning roller through the flow supply channel and the fluid channel.

[0021] Preferably, a drying component is also included, and the drying component includes:

[0022] a hot nitrogen source connected to the flow supply channel;

[0023] A source of isopropyl alcohol vapor is connected to the inlet end of the pump.

[0024] Preferably, the drying component further comprises:

[0025] An air guide pipe is longitudinally arranged in the upper part of the three-stage cleaning tank, and the upper end of the air guide pipe is connected to the isopropyl alcohol vapor source;

[0026] A lifting guide block, in which an air guide hole is arranged, the upper part of the air guide hole is sealed and slidably sleeved on the lower part of the air guide pipe, and the lower end of the air guide hole corresponds to the guide channel;

[0027] A floating block is fixedly arranged on the lifting guide block, and the floating block provides buoyancy for the lifting guide block so that the lifting guide block rises and falls along with the liquid level in the third cleaning tank;

[0028] The circulation pool is opened inside the main body and is located below the three-stage cleaning pool. The circulation pool is used to contain liquid discharged from the three-stage cleaning pool when drying.

[0029] Preferably, it also includes a heat preservation component, and the heat preservation component includes:

[0030] A first sliding cover and a second sliding cover, wherein the first sliding cover and the second sliding cover are both slidably disposed on the upper side of the main body, the first sliding cover reciprocates between the opening of the primary cleaning tank and the opening of the secondary cleaning tank, and the second sliding cover reciprocates between the opening of the secondary cleaning tank and the opening of the tertiary cleaning tank;

[0031] An insulation pipe is buried in the main body, the insulation pipe is located around the secondary cleaning tank, the inlet end of the insulation pipe extends upward from the main body and is located on one side of the secondary cleaning tank close to the tertiary cleaning tank;

[0032] A heat conducting hole is opened in the second sliding cover, and the inlet end of the heat conducting hole is located at the lower middle part of the second sliding cover. When the second sliding cover is located at the opening of the third-level cleaning pool, the outlet end of the heat conducting hole is connected to the inlet end of the insulation tube.

[0033] Preferably, the pressing assembly comprises:

[0034] A rotating frame, the middle part of which is rotatably arranged on the top of the frame body and rotates around the connection between the frame body and the frame body;

[0035] A pressing plate, which is fixedly arranged on the top of the rotating frame;

[0036] A flexible bag, which is arranged on the lower side of the pressure plate, and the flexible bag is connected to the fluid channel;

[0037] The float is fixedly arranged at the bottom end of the rotating frame, and the float drives the rotating frame to rotate after receiving the buoyancy provided by the liquid.

[0038] Preferably, the pressing assembly further comprises:

[0039] The pressing sheet is fixedly arranged on the lower side of the flexible bag, and the pressing sheet is equal in number to the epitaxial wafers in the frame and is arranged one-to-one.

[0040] Preferably, the pressing assembly further comprises:

[0041] A liquid-conducting box, which is fixedly arranged on the top of the frame, wherein the lower part of the liquid-conducting box is connected to the fluid channel, and the upper part of the liquid-conducting box is connected to the flexible bag;

[0042] A rotating rod, which is fixedly arranged at the middle part of the rotating frame, and the rotating rod passes through the liquid guiding box;

[0043] A water blocking plate, which is fixedly arranged at the middle part of the rotating rod and rotatably arranged inside the liquid guiding box, wherein the water blocking plate always maintains a seal with the inner wall of the liquid guiding box during the rotation process;

[0044] The elastic member is fixedly arranged between the top of the water blocking plate and the inner side wall of the liquid guiding box.

[0045] Preferably, the placement rack further comprises:

[0046] A bottom frame, which is fixedly arranged on the outer side of the bottom end of the frame;

[0047] The connecting parts are symmetrically fixedly arranged at the two ends of the top of the bottom frame, and the connecting parts cooperate with the mechanical arm to move the placement rack.

[0048] Preferably, the spraying direction of the spray holes of one of the cleaning rollers is toward the lower front side of the epitaxial wafer in the frame, and the spraying direction of the spray holes of the other cleaning roller is toward the lower back side of the epitaxial wafer in the frame.

[0049] The beneficial effects of the present invention are:

[0050] 1. The present invention rinses the epitaxial wafer by using a cleaning roller while the epitaxial wafer is immersed. The water on the outer side of the epitaxial wafer can buffer the impact force during rinsing to avoid scratches. Meanwhile, the attachments on the epitaxial wafer are also more easily detached from the epitaxial wafer.

[0051] 2. The present invention eliminates the transmission shaft, thereby preventing fine particles generated when the rotating shaft rotates from entering the tertiary cleaning tank, reducing the particle level of pure water in the tertiary cleaning tank, and reducing the amount of fine particles attached to the surface of the epitaxial wafer after cleaning.

[0052] 3. The present invention uses an air guide pipe and a lifting guide block to blow isopropyl alcohol vapor toward the surface of the epitaxial wafer when the water is drained from the three-stage cleaning tank. The surface tension of isopropyl alcohol is less than that of pure water, so that the isopropyl alcohol concentration on the surface of the epitaxial wafer is higher than that in pure water. The smaller surface tension of isopropyl alcohol removes water from the surface of the epitaxial wafer. When the epitaxial wafer is completely exposed to the water surface, hot nitrogen is blown toward the epitaxial wafer to quickly dry the epitaxial wafer and avoid water marks on the surface of the epitaxial wafer.

[0053] 4. The cleaning roller not only supports the epitaxial wafer in the placement rack, but also drives the epitaxial wafer to rotate. At the same time, the water flow during rinsing and the air flow during drying are both rushed to the epitaxial wafer through the cleaning roller, which simplifies the structure and avoids too many moving parts from generating fine particles during movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a schematic diagram of the structure of the present invention.

[0055] Figure 2 It is a structural cross-sectional view of the present invention.

[0056] Figure 3 For the present invention Figure 2 Enlarged view of point A in the middle.

[0057] Figure 4 It is a schematic diagram of the placement state of the epitaxial wafer of the present invention.

[0058] Figure 5 For the present invention Figure 4 Longitudinal cross-sectional view of .

[0059] Figure 6 For the present invention Figure 5 Cross-sectional view at BB in .

[0060] Figure 7 It is a structural schematic diagram of the placement rack of the present invention.

[0061] Figure 8 It is a structural sectional view of the placement rack of the present invention.

[0062] Fig. 9 It is a schematic structural diagram of the cleaning roller of the present invention.

[0063] Fig.10 It is a structural cross-sectional view of the cleaning roller of the present invention.

[0064] Fig.11 It is a schematic structural diagram of the clamping assembly of the present invention.

[0065] Fig.12 It is a structural cross-sectional view of the clamping assembly of the present invention.

[0066] Fig.13 It is a schematic structural diagram of the thermal insulation pipe of the present invention.

[0067] The accompanying drawings are marked as follows:

[0068] 1-main body; 2-primary cleaning pool; 3-secondary cleaning pool; 4-tertiary cleaning pool; 5-placing rack; 6-epitaxial wafer; 7-drying assembly; 8-insulating assembly; 9-pressing assembly; 10-flow channel; 11-flow channel; 12-pump; 501-frame; 502-placing slot; 503-fluid channel; 504-cleaning roller; 505-paddle; 506-spraying hole; 507-bottom frame; 508-connecting part; 701-hot nitrogen source ;702-isopropanol vapor source;703-air guide tube;704-lifting guide block;705-air guide hole;706-floating block;707-circulating pool;801-first sliding cover;802-second sliding cover;803-insulation tube;804-heat conduction hole;901-rotating frame;902-pressing plate;903-flexible bag;904-floating;905-pressing sheet;906-liquid guide box;907-rotating rod;908-water blocking plate;909-elastic part. DETAILED DESCRIPTION

[0069] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0071] Embodiment 1

[0072] The existing epitaxial wafer cleaning equipment is to spray after soaking and draining water. When spraying, the spraying water flow directly impacts the epitaxial wafer 6. When the impact force of the spraying water flow is small, it is not easy to remove the attachments on the surface of the epitaxial wafer 6. When the impact force of the spraying water flow is large, scratches will appear on the surface of the epitaxial wafer 6, resulting in a large surface roughness of the epitaxial wafer 6.

[0073] Reference Figures 1 to 10 A device for measuring the resistance value of an epitaxial wafer is disclosed. The device comprises a main body 1. A primary cleaning pool 2, a secondary cleaning pool 3 and a tertiary cleaning pool 4 are sequentially provided on the top of the main body 1. The primary cleaning pool 2 is an ultrasonic cleaning pool, which is used for ultrasonic cleaning of an epitaxial wafer 6 to remove pollutants attached to the surface of the epitaxial wafer 6. Ultrasonic cleaning is a prior art. An acetone solvent is contained in the secondary cleaning pool 3, and the primary cleaning pool 2, the secondary cleaning pool 3 and the tertiary cleaning pool 4 can be used to remove photoresist and organic residues on the surface of the epitaxial wafer 6. At the same time, an ultrasonic cleaning function can also be added to the secondary cleaning pool 3 to further improve the cleaning effect on the epitaxial wafer 6. The tertiary cleaning pool 4 is filled with deionized water. The epitaxial wafer 6 is immersed and sprayed with deionized water to completely remove the residual chemical substances on the surface of the epitaxial wafer 6.

[0074] It also includes a placement rack 5, which is used to store and place multiple epitaxial wafers 6, and the placement rack 5 is placed in the primary cleaning tank 2, the secondary cleaning tank 3 and the tertiary cleaning tank 4 in sequence by a robotic arm for cleaning.

[0075] In this embodiment, the placement rack 5 includes a rack body 501; a placement groove 502 is evenly opened in the middle of the rack body 501, and the placement groove 502 is used to store the epitaxial wafer 6. The width of the placement groove 502 is slightly larger than the thickness of the epitaxial wafer 6, so that the epitaxial wafer 6 can rotate freely in the placement groove 502; a fluid channel 503 is opened inside the rack body 501, one end of the fluid channel 503 passes through the bottom end of the rack body 501, and the other end extends upward to the top end of the rack body 501; two cleaning rollers 504 are arranged on both sides of the lower part of the rack body 501 in a mirror-image relationship, and the cleaning rollers 504 are hollow cylindrical and rotatably arranged on the rack body 50 1. Both ends of the cleaning roller 504 are connected to the fluid channel 503. The cleaning roller 504 supports the bottom of the epitaxial wafer 6 placed in the frame 501. A paddle 505 is fixedly set at the end of the cleaning roller 504. When the fluid in the fluid channel 503 enters the cleaning roller 504, the paddle 505 drives the cleaning roller 504 to rotate. When the cleaning roller 504 rotates, it drives the epitaxial wafer 6 in the frame 501 to rotate. A plurality of spray holes 506 are evenly opened in the middle of the cleaning roller 504. The spray holes 506 and the placement slots 502 are staggered one by one. The spray direction of the spray hole 506 is toward the side of the epitaxial wafer 6 in the corresponding placement slot 502.

[0076] The spraying direction of the spray hole 506 of one cleaning roller 504 is toward the lower front part of the epitaxial wafer 6 inside the frame 501, and the spraying direction of the spray hole 506 of the other cleaning roller 504 is toward the lower back part of the epitaxial wafer 6 inside the frame 501. The spraying direction of the spray hole 506 does not coincide with the radial direction of the cleaning roller 504. The reverse force of the spray hole 506 during spraying can also drive the cleaning roller 504 to rotate.

[0077] In order to facilitate the movement of the placement rack 5 and ensure the stability of the position state of the placement rack 5 in the primary cleaning tank 2, the secondary cleaning tank 3 and the tertiary cleaning tank 4, the placement rack 5 also includes: a bottom frame 507 is fixedly provided on the outer side of the bottom end of the frame body 501; connecting parts 508 are symmetrically fixedly provided at both ends of the top of the bottom frame 507, and the connecting parts 508 cooperate with the robot arm to move the placement rack 5.

[0078] In order to ensure that the epitaxial wafer 6 in the placement rack 5 can reliably contact the cleaning roller 504 , clamping assemblies 9 are rotatably provided on both sides of the top of the placement rack 5 . The clamping assemblies 9 restrict the epitaxial wafer 6 inside the placement rack 5 so that the epitaxial wafer 6 contacts the cleaning roller 504 .

[0079] In order to spray the deionized water in the tertiary cleaning tank 4 onto the epitaxial wafer 6, a flow supply channel 10 is opened in the main body 1, and the flow supply channel 10 is located below the tertiary cleaning tank 4. When the placement rack 5 is located on the bottom surface of the tertiary cleaning tank 4, the flow supply channel 10 is connected with the fluid channel 503; a guide channel 11 is opened in the main body 1, and the guide channel 11 is located on the side of the tertiary cleaning tank 4; a pump 12 is installed on the outside of the tertiary cleaning tank 4, and the outlet end of the pump 12 is connected to the flow supply channel 10, and the inlet end of the pump 12 is connected to the tertiary cleaning tank 4 through the guide channel 11, and the pump 12 supplies the liquid in the tertiary cleaning tank 4 to the cleaning roller 504 through the flow supply channel 10 and the fluid channel 503.

[0080] By washing the epitaxial wafer 6 in an immersed state with the cleaning roller 504 , the water outside the epitaxial wafer 6 can buffer the impact force during washing to avoid scratches, and at the same time, the attachments on the epitaxial wafer 6 are easier to separate from the epitaxial wafer 6 .

[0081] The present invention eliminates the transmission shaft, thereby preventing fine particles generated when the rotating shaft rotates from entering the tertiary cleaning tank 4, reducing the particle level of pure water in the tertiary cleaning tank 4, and reducing the amount of fine particles attached to the surface of the epitaxial wafer 6 after cleaning.

[0082] Embodiment 2

[0083] When the existing epitaxial wafer 6 surface pretreatment device is drying, even if the air guide tube 703 is repeatedly translated to make the blowing range more comprehensive, it is still impossible to quickly separate the water from the epitaxial wafer 6, which is prone to insufficient drying. The water on the surface of the epitaxial wafer 6 forms water droplets, which react with silicon dioxide formed by oxidation of silicon in water to form stable metasilicic acid. These metasilicic acids appear as granular water marks on the surface of the silicon epitaxial wafer 6 after cleaning. The water marks will affect the integrity of the etching, cause regional chip failure, and cause the final yield loss.

[0084] Reference Figures 1 to 3 The present invention also includes a drying component 7, which includes a hot nitrogen source 701, an isopropyl alcohol vapor source 702, an air guide pipe 703 and a lifting guide block 704. The hot nitrogen source 701 is connected to the flow supply channel 10, the air guide pipe 703 is longitudinally arranged at the upper part of the third-level cleaning pool 4, and the upper end of the air guide pipe 703 is connected to the isopropyl alcohol vapor source 702; the lifting guide block 704 is provided with an air guide hole 705, the upper part of the air guide hole 705 is sealed and slidably sleeved at the lower part of the air guide pipe 703, and the lower end of the air guide hole 705 corresponds to the flow guide channel 11; the lifting guide block 704 is fixedly provided with a floating block 706, and the floating block 706 provides buoyancy for the lifting guide block 704, so that the lifting guide block 704 rises and falls with the liquid level in the third cleaning pool.

[0085] In order to store the deionized water discharged from the tertiary cleaning pool 4 during drying, a circulation pool 707 is provided inside the main body 1. The circulation pool 707 is located below the tertiary cleaning pool 4 and is used to accommodate the liquid discharged from the tertiary cleaning pool 4 during drying.

[0086] During cleaning, the liquid level in the tertiary cleaning pool 4 is at a high place, and the lifting guide block 704 rises due to buoyancy. At this time, the guide channel 11 is directly connected to the tertiary cleaning pool 4, and the pump 12 pumps the deionized water in the tertiary cleaning pool 4 into the cleaning roller 504. The deionized water is sprayed from the cleaning roller 504 to rinse the epitaxial wafer 6.

[0087] After cleaning, the deionized water in the tertiary cleaning pool 4 flows into the circulation pool 707, the liquid level in the tertiary cleaning pool 4 gradually decreases, and the lifting guide block 704 gradually decreases with the liquid level. When the liquid level drops to the point where the deionized water sprayed from the cleaning roller 504 rinses the epitaxial wafer 6, the lifting guide block 704 drops to the limit position. At this time, the lower part of the lifting guide block 704 is located at the connection point between the guide channel 11 and the tertiary cleaning pool 4, and the lower end of the air guide hole 705 is connected to the guide channel 11. The deionized water in the tertiary cleaning pool 4 cannot enter the pump 12 through the guide channel 11. The pump 12 draws isopropyl alcohol vapor into the cleaning roller 504, and the isopropyl alcohol vapor is sprayed from the cleaning roller 504 to the epitaxial wafer 6, accelerating the water on the epitaxial wafer 6 to separate from the epitaxial wafer 6. When the liquid level in the tertiary cleaning pool 4 continues to drop until the epitaxial wafer 6 in the placement rack 5 is completely exposed to the liquid surface, hot nitrogen is introduced into the flow supply channel 10. At this time, the lower end of the air guide hole 705 is still connected to the guide channel 11, and the hot nitrogen and isopropyl alcohol vapor are sprayed from the cleaning roller 504 toward the epitaxial wafer 6, so that the epitaxial wafer 6 is quickly and fully dried.

[0088] When draining water from the third-level cleaning pool 4, isopropyl alcohol vapor is blown toward the surface of the epitaxial wafer 6 through the air guide 703 and the lifting guide block 704. The surface tension of isopropyl alcohol is smaller than that of pure water, so that the isopropyl alcohol concentration on the surface of the epitaxial wafer 6 is higher than that in the pure water. The smaller surface tension of isopropyl alcohol removes water from the surface of the epitaxial wafer 6. When the epitaxial wafer 6 is completely exposed to the water surface, hot nitrogen is blown toward the epitaxial wafer 6 to quickly dry the epitaxial wafer 6 and avoid water marks on the surface of the epitaxial wafer 6.

[0089] Embodiment 3

[0090] The primary cleaning tank 2, the secondary cleaning tank 3 and the tertiary cleaning tank 4 of the existing epitaxial wafer 6 surface pretreatment device are all in an open state. The secondary cleaning tank 3 is filled with acetone solvent, and the acetone solvent has a certain volatility. The concentration and temperature of the acetone solvent will also affect the effect of removing surface particles. If the concentration and temperature of the acetone solvent are too low, the particle removal ability of the acetone solvent will be reduced, but if the concentration and temperature are too high, the volatilization of the acetone solvent will be accelerated and the roughness of the surface of the epitaxial wafer 6 will be affected.

[0091] Reference Figure 1 , Figure 2 and Fig.13 The present invention also includes a heat preservation component 8, which includes a first sliding cover 801, a second sliding cover 802 and a heat preservation pipe 803.

[0092] Among them, the first sliding cover 801 and the second sliding cover 802 are both slidably arranged on the upper side of the main body 1, the first sliding cover 801 slides back and forth at the opening of the first cleaning tank 2 and the opening of the second cleaning tank 3, and the second sliding cover 802 slides back and forth at the opening of the second cleaning tank 3 and the opening of the tertiary cleaning tank 4.

[0093] The first sliding cover 801 covers the opening of the secondary cleaning tank 3 to reduce the volatilization amount of the acetone solvent and keep the concentration of the acetone solvent at a more optimal value. The second sliding cover 802 covers the opening of the tertiary cleaning tank 4 to prevent external fine particles from entering the tertiary cleaning tank 4 and causing secondary contamination to the epitaxial wafer 6.

[0094] The insulation pipe 803 is buried in the main body 1, and the insulation pipe 803 is located around the secondary cleaning pool 3. The inlet end of the insulation pipe 803 extends upward from the main body 1 and is located on the side of the secondary cleaning pool 3 close to the tertiary cleaning pool 4. A temperature conduction hole 804 is opened in the second sliding cover 802, and the inlet end of the temperature conduction hole 804 is located on the lower middle side of the second sliding cover 802. When the second sliding cover 802 is located at the opening of the tertiary cleaning pool 4, the outlet end of the temperature conduction hole 804 is connected to the inlet end of the insulation pipe 803.

[0095] During drying, hot nitrogen enters the insulation pipe 803 from the tertiary cleaning tank 4 through the heat conducting hole 804, and the hot nitrogen exchanges heat with the acetone solvent in the secondary cleaning tank 3 when circulating in the insulation pipe 803. The acetone solvent can be heated every time during drying, and the acetone solvent is heated at intervals to ensure the particle removal ability of the acetone solvent, while also preventing the acetone solvent from volatilizing due to excessively high temperature.

[0096] Embodiment 4

[0097] In order to ensure that the epitaxial wafers 6 in the placement rack 5 can reliably contact the cleaning rollers 504 during cleaning and drying, so that the cleaning rollers 504 can drive the epitaxial wafers 6 to rotate and ensure the cleaning and drying effects, a clamping assembly 9 is provided.

[0098] The clamping assembly 9 of the existing epitaxial wafer 6 surface pretreatment device relies on the overall pressure plate 902 to press the epitaxial wafer 6 downward. Although it can ensure that the epitaxial wafer 6 cannot float up, the outer dimensions of the epitaxial wafer 6 vary to a certain extent. The epitaxial wafers 6 on the placement rack 5 are multiple and arranged in a horizontal array. The pressure plate 902 cannot reach all the epitaxial wafers 6 on the placement rack 5, and it is also impossible to ensure that all the epitaxial wafers 6 can reliably reach the cleaning roller 504. During rinsing or drying, some epitaxial wafers 6 cannot rotate with the cleaning roller 504, thereby reducing the area for rinsing or drying.

[0099] Reference Figure 11 to Figure 12 In this embodiment, the clamping assembly 9 includes a rotating frame 901, a pressing plate 902, a flexible bag 903 and a float 904.

[0100] The middle part of the rotating frame 901 is rotatably arranged at the top of the frame body 501, and rotates around the connection between it and the frame body 501; the pressure plate 902 is fixedly arranged at the top of the rotating frame 901; the flexible bag 903 is arranged on the lower side of the pressure plate 902, and the flexible bag 903 is connected to the fluid channel 503; the float 904 is fixedly arranged at the bottom end of the rotating frame 901, and the float 904 will drive the rotating frame 901 to rotate after being subjected to the buoyancy provided by the liquid.

[0101] During rinsing and drying, the fluid in the fluid channel 503 fills the flexible bladder 903 , and the flexible bladder 903 expands, so that the downward pressure of the pressure plate 902 is transmitted to each epitaxial wafer 6 .

[0102] The flexible capsule 903 usually has a high friction coefficient. In order to avoid a large resistance to the rotation of the epitaxial wafer 6 when the flexible capsule 903 is pressed against the epitaxial wafer 6, the clamping assembly 9 also includes a pressing sheet 905. Multiple pressing sheets 905 are fixedly arranged on the lower side of the flexible capsule 903. The number of pressing sheets 905 is equal to the number of epitaxial wafers 6 in the frame 501 and they are arranged one by one. The flexible capsule 903 is pressed on the epitaxial wafer 6 through the pressing sheets 905 to press each epitaxial wafer 6 onto the cleaning roller 504. The pressing sheets 905 are made of a material with a low friction coefficient and will not affect the rotation of the epitaxial wafer 6.

[0103] In order to ensure that the pressure plate 902 can still press against the epitaxial wafer 6 when the liquid level drops, the clamping assembly 9 also includes a liquid guiding box 906, a rotating rod 907, a water blocking plate 908 and an elastic member 909; wherein the liquid guiding box 906 is fixedly arranged at the top of the frame 501, the lower part of the liquid guiding box 906 is connected to the fluid channel 503, and the upper part is connected to the flexible bag 903; the rotating rod 907 is fixedly arranged at the middle part of the rotating frame 901, and the rotating rod 907 passes through the liquid guiding box 906; the water blocking plate 908 is fixedly arranged at the middle part of the rotating rod 907, and is rotatably arranged inside the liquid guiding box 906, and the water blocking plate 908 always maintains a seal with the inner wall of the liquid guiding box 906 during the rotation process; the elastic member 909 is fixedly arranged between the top of the water blocking plate 908 and the inner side wall of the liquid guiding box 906.

[0104] After the fluid in the fluid channel 503 enters the liquid guiding box 906 , it gradually fills up the liquid guiding box 906 . During this process, the water blocking plate 908 is pushed to rotate. The water blocking plate 908 drives the pressing plate 902 to press toward the epitaxial wafer 6 through the rotating rod 907 .

[0105] During cleaning and drying, the epitaxial wafers 6 in the placement rack 5 can all reliably reach the cleaning rollers 504, so that the cleaning rollers 504 can drive the epitaxial wafers 6 to rotate, thereby ensuring the cleaning and drying effects.

[0106] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for measuring resistance value of an epitaxial wafer, comprising a main body (1), wherein a primary cleaning pool (2), a secondary cleaning pool (3) and a tertiary cleaning pool (4) are sequentially provided on the top of the main body (1), characterized in that: Also includes: A placement rack (5) is used to store and place a plurality of epitaxial wafers (6), and the placement rack (5) is sequentially placed into a primary cleaning pool (2), a secondary cleaning pool (3) and a tertiary cleaning pool (4) by a mechanical arm for cleaning. The placement rack (5) comprises: Frame (501); A placement groove (502) is evenly arranged in the middle of the frame (501); A fluid channel (503) is opened inside the frame (501), with one end penetrating to the bottom end of the frame (501) and the other end extending upward to the top end of the frame (501); a cleaning roller (504) in the shape of a hollow circular tube, the cleaning roller (504) being rotatably arranged on the frame (501), the two ends of the cleaning roller (504) being connected to the fluid channel (503), the two cleaning rollers (504) being arranged in mirror images on both sides of the lower part of the frame (501), the cleaning rollers (504) supporting the bottom of the epitaxial wafer (6) placed in the frame (501); a paddle (505) fixedly arranged at the end of the cleaning roller (504); when the fluid in the fluid channel (503) enters the cleaning roller (504), the paddle (505) drives the cleaning roller (504) to rotate; when the cleaning roller (504) rotates, the epitaxial wafer (6) in the frame (501) is driven to rotate; Spray holes (506) are evenly arranged in the middle of the cleaning roller (504), the spray holes (506) and the placement grooves (502) are arranged one by one in an alternating manner, and the spray direction of the spray holes (506) is toward the side of the epitaxial wafer (6) in the corresponding placement groove (502); A clamping assembly (9) rotatably disposed on both sides of the top of the placement rack (5), the clamping assembly (9) confines the epitaxial wafer (6) inside the placement rack (5) so that the epitaxial wafer (6) abuts against the cleaning roller (504); A fluid supply channel (10) arranged in the main body (1) and located below the third-level cleaning pool (4); when the placement rack (5) is located on the bottom surface of the third-level cleaning pool (4), the fluid supply channel (10) is in communication with the fluid channel (503); A guide channel (11), which is arranged in the main body (1) and located on the side of the third-level cleaning tank (4); a pump (12) disposed on one side of the three-stage cleaning pool (4); the outlet end of the pump (12) is connected to the flow supply channel (10); the inlet end of the pump (12) is connected to the three-stage cleaning pool (4) through the flow guide channel (11); the pump (12) supplies liquid in the three-stage cleaning pool (4) to the cleaning roller (504) through the flow supply channel (10) and the fluid channel (503); It also includes a drying component (7), wherein the drying component (7) includes: A hot nitrogen source (701) connected to the flow supply channel (10); an isopropyl alcohol vapor source (702) connected to the inlet end of the pump (12); An air guide pipe (703) is longitudinally arranged in the upper part of the third-level cleaning tank (4), and the upper end of the air guide pipe (703) is connected to the isopropyl alcohol vapor source (702); A lifting guide block (704) is provided with an air guide hole (705) therein, the upper portion of the air guide hole (705) is sealed and slidably sleeved on the lower portion of the air guide pipe (703), and the lower end of the air guide hole (705) corresponds to the guide channel (11); The floating block (706) is fixedly arranged on the lifting guide block (704), and the floating block (706) provides buoyancy for the lifting guide block (704), so that the lifting guide block (704) rises and falls along with the liquid level in the third cleaning tank.

2. The epitaxial wafer resistance value measurement preprocessing device according to claim 1, characterized in that: The drying component (7) further comprises: The circulation pool (707) is opened inside the main body (1) and is located below the tertiary cleaning pool (4). The circulation pool (707) is used to accommodate liquid discharged from the tertiary cleaning pool (4) during drying.

3. The epitaxial wafer resistance value measurement preprocessing device according to claim 1, characterized in that: It also includes a heat preservation component (8), wherein the heat preservation component (8) includes: A first sliding cover (801) and a second sliding cover (802), wherein the first sliding cover (801) and the second sliding cover (802) are both slidably arranged on the upper side of the main body (1), the first sliding cover (801) slides back and forth at the opening of the first-level cleaning tank (2) and the opening of the second-level cleaning tank (3), and the second sliding cover (802) slides back and forth at the opening of the second-level cleaning tank (3) and the opening of the third-level cleaning tank (4); An insulation pipe (803) is buried in the main body (1), the insulation pipe (803) is located around the secondary cleaning tank (3), and the inlet end of the insulation pipe (803) extends upward from the main body (1) and is located on a side of the secondary cleaning tank (3) close to the tertiary cleaning tank (4); A temperature conducting hole (804) is provided in the second sliding cover (802), the inlet end of the temperature conducting hole (804) is located at the lower middle part of the second sliding cover (802), and when the second sliding cover (802) is located at the opening of the third-stage cleaning pool (4), the outlet end of the temperature conducting hole (804) is connected to the inlet end of the insulation tube (803).

4. The epitaxial wafer resistance value measurement preprocessing device according to claim 1, characterized in that: The pressing assembly (9) comprises: A rotating frame (901), the middle of which is rotatably disposed at the top of the frame body (501) and rotates around the connection between it and the frame body (501); A pressing plate (902) fixedly disposed on the top of the rotating frame (901); A flexible bag (903), which is arranged on the lower side of the pressure plate (902), and the flexible bag (903) is connected to the fluid channel (503); The float (904) is fixedly arranged at the bottom end of the rotating frame (901). The float (904) drives the rotating frame (901) to rotate after receiving the buoyancy provided by the liquid.

5. The epitaxial wafer resistance value measurement preprocessing device according to claim 4, characterized in that: The pressing assembly (9) further comprises: A pressing sheet (905) is fixedly arranged on the lower side of the flexible bag (903), and the pressing sheets (905) are equal in number to the epitaxial sheets (6) in the frame (501) and are arranged in a one-to-one correspondence.

6. The epitaxial wafer resistance value measurement preprocessing device according to claim 5, characterized in that: The pressing assembly (9) further comprises: A liquid conducting box (906) is fixedly arranged on the top of the frame (501), the lower part of the liquid conducting box (906) is connected to the fluid channel (503), and the upper part is connected to the flexible bag (903); A rotating rod (907) fixedly disposed at the middle portion of the rotating frame (901), the rotating rod (907) passing through the liquid guiding box (906); a water blocking plate (908) fixedly disposed at the middle portion of the rotating rod (907) and rotatably disposed inside the liquid guiding box (906); the water blocking plate (908) always maintains a seal with the inner wall of the liquid guiding box (906) during the rotation process; An elastic member (909) is fixedly disposed between the top of the water blocking plate (908) and the inner side wall of the liquid guiding box (906).

7. The epitaxial wafer resistance value measurement preprocessing device according to claim 1, characterized in that: The placement rack (5) further comprises: A bottom frame (507) fixedly disposed on the outer side of the bottom end of the frame (501); The connecting parts (508) are symmetrically fixedly arranged at the two ends of the top of the bottom frame (507); the connecting parts (508) cooperate with the mechanical arm to move the placement rack (5).

8. The epitaxial wafer resistance value measurement preprocessing device according to claim 1, characterized in that: The spraying direction of the spray holes (506) of one of the cleaning rollers (504) is toward the lower front side of the epitaxial wafer (6) inside the frame (501), and the spraying direction of the spray holes (506) of the other cleaning roller (504) is toward the lower back side of the epitaxial wafer (6) inside the frame (501).

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