Fixed semiconductor wafer cleavage device

By designing a fixed semiconductor wafer cleaving device, and utilizing a multi-axis linkage mechanism and precision cutting tools, the problems of microcrack propagation and step control in semiconductor laser processing were solved, achieving efficient and precise wafer cleaving processing.

CN121268080AActive Publication Date: 2026-01-06UNIV OF SHANGHAI FOR SCI & TECH
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Patent Information

Application Number
CN202511197467.4
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-08-26
Publication Date
2026-01-06
Estimated Expiration
2045-08-26

AI Technical Summary

Technical Problem

Existing semiconductor laser processing equipment is unable to meet the surface quality requirements of the resonant cavity, especially in the process of gallium arsenide cleavage, where the propagation of microcracks and cleavage steps are difficult to control, affecting laser performance.

Method used

A fixed semiconductor wafer cleaving device is designed, which adopts an L-shaped support stage and a multi-axis linkage mechanism, combined with a diamond scribing blade and a ceramic cleaving blade. Through vacuum adsorption and force sensing feedback system, it realizes precision scribing and cleaving processing, avoiding errors caused by wafer movement.

Benefits of technology

It improves the processing quality and efficiency of semiconductor cleavage surfaces, ensures processing accuracy, is suitable for mass production, and reduces wafer damage and errors.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention discloses a fixed semiconductor wafer cleavage device, which is provided with a scribing device and a splitting device, the two parts are respectively provided with a fixing mechanism and a processing mechanism and can move along a guide rail, a wafer mounting mechanism is arranged in the middle of the cleavage device, and a wafer is fixed on the wafer mounting mechanism through a wafer ring. The scribing fixing mechanism carries out vacuum adsorption, the scribing machining mechanism carries out scribing on the wafer at the designated position of the wafer, the wafer fixing mechanism supports the wafer at the lower portion of the wafer mounting mechanism, and a ceramic knife of the wafer machining mechanism is aligned with the back of a wafer scratch and presses downwards, so that the wafer is cleaved and broken along the scratch. Therefore, the semiconductor cleavage automatic processing of the fixed wafer is realized.
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Description

Technical Field

[0001] This invention relates to a fixed semiconductor wafer cleaving device, belonging to the field of semiconductor optoelectronic device processing technology. Background Technology

[0002] With the rapid development and widespread application of semiconductor lasers, the performance requirements of laser processing for semiconductor lasers are becoming increasingly demanding. Existing processing equipment is insufficient to meet the manufacturing needs of core components of semiconductor lasers. The resonant cavity is a crucial component of a laser, and the surface quality of the resonant cavity surface affects the oscillation of the laser source. Currently, the propagation of microcracks and cleavage steps generated during gallium arsenide cleaving are significant challenges in resonant cavity processing. Designing an ultra-precision semiconductor cleaving surface processing device can improve the performance of semiconductor lasers, making this a pressing need. Summary of the Invention

[0003] The purpose of this invention is to improve the processing quality and efficiency of semiconductor cleaving surfaces, and to provide a fixed semiconductor cleaving processing apparatus to meet the needs of mass production and improved processing accuracy.

[0004] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0005] A fixed semiconductor wafer cleaving apparatus includes an L-shaped support platform with upper and lower guide rails. A dicing and fixing mechanism and a dicing processing mechanism are slidably mounted on the upper guide rail, and the same mechanism is mounted on the lower guide rail. A wafer mounting mechanism is located in the middle of the support platform, between the upper and lower guide rails. The wafer mounting mechanism includes a rotating shaft for adjusting the dicing crystal orientation and a wafer ring for supporting and protecting the wafer. The mechanism also includes a magnetic suction device and positioning pins for positioning and fixing the wafer ring. The dicing processing mechanism includes a diamond dicing blade for wafer dicing, which has features for setting... A constant dicing force force sensor and feedback system are included. The dicing mechanism has three degrees of freedom for continuous automatic dicing. The dicing fixing mechanism has a vacuum chuck to ensure that the wafer and the diamond dicing blade are parallel to each other through vacuum adsorption, ensuring constant dicing force and dicing depth during the dicing process. The dicing fixing mechanism has a detachable dicing disk for setting different dicing spacing according to the processing conditions. The dicing mechanism is equipped with a ceramic dicing blade, which has a force sensor and feedback system to set the pressure parameters according to different materials and to detect the pressure applied by the ceramic dicing blade to the wafer in real time during the dicing process.

[0006] Preferably, the magnetic suction device has a flat annular surface, and at least one positioning pin is provided on the flat annular surface. The wafer ring is placed on the flat annular surface by the positioning pin, and the wafer ring is provided with a positioning slot that cooperates with the positioning pin for positioning.

[0007] Preferably, the wafer ring is connected to the wafer via a blue film, and the vacuum chuck adsorbs the blue film to keep the wafer horizontal.

[0008] Preferably, the dicing processing mechanism has a three-axis linkage mechanism, which consists of an x-axis moving mechanism, a y-axis moving mechanism, and a z-axis moving mechanism. The diamond dicing cutter is mounted on the y-axis moving mechanism and is driven to move back and forth by the y-axis moving mechanism. The y-axis moving mechanism is mounted on the z-axis moving mechanism to realize the up and down movement of the diamond dicing cutter. The z-axis moving mechanism is mounted on the x-axis moving mechanism and slides on the lower guide rail to realize the left and right movement of the diamond dicing cutter.

[0009] Furthermore, the x-axis moving mechanism includes an x-axis support plate, which is slidably mounted on the lower guide rail; the z-axis moving mechanism includes a z-axis guide rail and a z-axis support plate, with the z-axis guide rail mounted on the x-axis support plate and the z-axis support plate slidably mounted on the z-axis guide rail; the y-axis moving mechanism includes a y-axis guide rail and a y-axis support plate, with the y-axis guide rail mounted on the z-axis support plate and the y-axis support plate slidably mounted on the y-axis guide rail; the x-axis support plate, y-axis support plate, and z-axis support plate are all driven to slide by a high-precision linear motor, and the diamond scribing tool is mounted on the y-axis support plate.

[0010] Furthermore, the diamond scribing tool is inclined at a 60° angle on the y-axis support plate.

[0011] Preferably, the flaking processing mechanism has a two-axis linkage mechanism, which includes an x-axis moving mechanism and a z-axis moving mechanism. The x-axis moving mechanism has a second x-axis support plate, which is slidably mounted on the upper guide rail. The z-axis moving mechanism has a second z-axis support arm and a second z-axis guide rail. The second z-axis guide rail is mounted on the second x-axis support plate, and the second z-axis support arm is slidably mounted on the second z-axis guide rail. The ceramic flaking blade is mounted on the second z-axis support arm. Both the second x-axis support plate and the second z-axis support arm are driven to slide by a high-precision linear motor.

[0012] Preferably, the sharding disc has several grooves at equal intervals, which are arranged to correspond to the scratches and are used for support during the back pressure process of sharding.

[0013] Preferably, the sliding of the dicing and fixing mechanism, the dicing processing mechanism, the dicing processing mechanism and the dicing and fixing mechanism are all positioned with high precision by a grating ruler displacement sensor, and all are equipped with soft and hard limits to prevent accidents from happening to the equipment.

[0014] The fixed semiconductor wafer cleaving device provided by this invention has the following advantages:

[0015] The present invention has a simple structure, and the processing does not require moving the wafer, which improves processing efficiency and avoids errors and damage to the wafer during the wafer moving process. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a fixed semiconductor wafer cleaving device provided in an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the cleavage slicing device provided in an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the wafer ring structure according to an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the cleavage fragmentation device provided in an embodiment of the present invention;

[0020] Figure 5 This is a schematic diagram of the sharded disk structure according to an embodiment of the present invention;

[0021] In the picture:

[0022] 1-Support platform; 2-Upper guide rail; 3-Lower guide rail; 31-Linear motor stator; 4-Dictating fixing mechanism; 41-Vacuum chuck; 5-Dictating processing mechanism; 51-Diamond dicing cutter; 52-X-axis moving mechanism; 53-Y-axis moving mechanism; 531-Y-axis guide rail one; 532-Y-axis support plate one; 54-Z-axis moving mechanism; 541-Z-axis guide rail one; 542-Z-axis support plate one; 6-Ceramic dicing processing mechanism; 61-Ceramic dicing cutter; 7-Ceramic dicing fixing mechanism; 71-Ceramic dicing disk; 711-Groove; 8-Wafer mounting mechanism; 81-Positioning pin; 9-Wafer ring; 91-Positioning bayonet; 10-X-axis support plate two; 11-Z-axis moving mechanism; 111-Z-axis support arm; 112-Z-axis guide rail two; 12-Limit block. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Reference Figure 1A fixed semiconductor wafer cleaving apparatus includes an L-shaped support platform 1 with upper and lower guide rails on the support platform 1. A wafer mounting mechanism 8 is installed in the middle of the support platform 1 between the upper guide rail 2 and the lower guide rail 3. A dicing device and a dicing device are slidably mounted on the support platform 1 via the upper guide rail 2 and the lower guide rail 3. The dicing device includes a dicing fixing mechanism 4 and a dicing processing mechanism 5. The dicing device includes a dicing processing mechanism 6 and a dicing fixing mechanism 7.

[0025] The dicing and fixing mechanism 4 and the dicing processing mechanism 6 are installed on the upper guide rail 2, and the dicing processing mechanism 5 and the dicing and fixing mechanism 7 are installed on the lower guide rail 3. Both can move along the guide rails. Since the mechanical dicing and dicing process adopts a pressing method, and the dicing and dicing processes are located on the front and back sides of the wafer respectively, the dicing and fixing mechanism 4 and the dicing processing mechanism 6 are placed on the upper guide rail 2, and the dicing and fixing mechanism 7 is placed on the lower guide rail 3. The dicing and dicing operations can be completed on the front and back sides of the wafer without flipping the wafer.

[0026] Reference Figures 1-4 The wafer mounting mechanism 8 has a magnetic suction device and a rotating shaft. The magnetic suction device is rotatably mounted on the support platform 1 via the rotating shaft. The magnetic suction device is a ring-shaped device with a flat ring surface. At least one positioning pin 81 is integrally formed on the flat ring surface. The wafer ring 9, which is used to support and protect the wafer, is placed on the flat ring surface by the positioning pin 81 and is magnetically fixed by the magnetic suction device. The wafer ring 9 is provided with a positioning slot 91 that cooperates with the positioning pin 81 for precise positioning. The dicing process and the dicing process are completed by the dicing processing mechanism 5 and the dicing processing mechanism 6, respectively, thereby avoiding errors caused during wafer movement and errors caused by repositioning before wafer dicing. The rotating shaft (not shown in the figure) is driven to rotate by a motor. The dicing crystal orientation is adjusted by the horizontal adjustment function. In this embodiment, the rotating shaft is preferably a high-precision rotating shaft. The magnetic suction device and the rotation adjustment of the rotating shaft are existing technologies and will not be described in detail.

[0027] Reference Figure 1 and Figure 2 The dicing mechanism 5 includes a diamond dicing blade 51 and a three-axis linkage mechanism. The diamond dicing blade 51 is mounted on the three-axis linkage mechanism for continuous automatic dicing of the wafer fixed on the wafer mounting mechanism 8. A force sensor and a feedback system are installed on the cutting edge of the diamond dicing blade 51. The force sensor and the feedback system cooperate with the three-axis linkage mechanism to set a constant dicing force for the diamond dicing blade 51. In this embodiment, the use of the force sensor and the feedback system are existing technologies and will not be described in detail.

[0028] The three-axis linkage mechanism consists of an x-axis moving mechanism 52, a y-axis moving mechanism 53, and a z-axis moving mechanism 54. The diamond cutting tool 51 is mounted on the y-axis moving mechanism 53 and is driven to move back and forth by the y-axis moving mechanism 53. The y-axis moving mechanism 53 is mounted on the z-axis moving mechanism 54 to realize the up and down movement of the diamond cutting tool 51. The z-axis moving mechanism 54 is mounted on the x-axis moving mechanism 52, and the x-axis moving mechanism 52 is slidably mounted on the lower guide rail 3 to realize the left and right movement of the diamond cutting tool 51.

[0029] Specifically, the x-axis moving mechanism 52 includes an x-axis support plate, on which a linear motor actuator is mounted and placed on a lower guide rail 3. A linear motor stator 31, which works in conjunction with the linear motor actuator, is mounted on the lower guide rail 3. Limiting blocks 12 are bolted to both ends of the lower guide rail 3 on the support platform 1 to hard limit the linear motor actuator on the x-axis support plate. The z-axis moving mechanism 54 includes a z-axis guide rail 541 and a z-axis support plate 542. The z-axis guide rail 541 is bolted to the x-axis support plate, and the z-axis support plate 542 is slidably mounted on the z-axis guide rail 541. The y-axis moving mechanism 53 includes a y-axis guide rail 531 and a y-axis support plate 532. 1. The diamond scriber 51 is fixedly mounted on the z-axis support plate 542 by bolts, and the y-axis support plate 532 is slidably mounted on the y-axis guide rail 531. Both the y-axis support plate 532 and the z-axis support plate 542 are driven by high-precision linear motors. The diamond scriber 51 is mounted at a 60° angle on the y-axis support plate 532. During the dicing operation, the diamond scriber 51 can be moved to the processing area through the cooperation of the three-axis linkage mechanism to complete multiple equidistant dicing operations, ensuring the accuracy and stability of the linear motion of the dicing. The movement of each linear motor on the three-axis linkage mechanism is controlled by an external PC to ensure consistent processing of each wafer. The linkage control of the linear motors by the external PC is existing technology and will not be described in detail.

[0030] Reference Figures 1-4The dicing and fixing mechanism 4, the dicing processing mechanism 6, and the dicing and fixing mechanism 7 all have a two-axis linkage mechanism, which includes an x-axis moving mechanism and a z-axis moving mechanism 11. The x-axis moving mechanism has an x-axis support plate 2 10, on which a linear motor mover is mounted and placed on an upper guide rail 2. A linear motor stator 31 that cooperates with the linear motor mover is mounted on the upper guide rail 2. The support platform 1 is located on the upper guide rail 2 and is also equipped with a limit block 12 for hard limiting. The z-axis moving mechanism 11 has a z-axis support arm 111 and a z-axis guide rail 2 112. The z-axis guide rail 2 112 is fixedly mounted on the x-axis support plate 2 10 by bolts. The z-axis support arm 111 is slidably mounted on the z-axis guide rail 2 112. The z-axis support arm 111 is driven to slide by a high-precision linear motor. The size and structure of the z-axis support arm 111 of the dicing and fixing mechanism 4, the dicing processing mechanism 6, and the dicing and fixing mechanism 7 are configured according to actual installation requirements.

[0031] Reference Figure 1 and Figure 2 The dicing and fixing mechanism 4 has a vacuum chuck 41, which is mounted on the z-axis support arm 111z of the dicing and fixing mechanism 4. The vacuum chuck 41 ensures that the processing trajectory of the wafer and the diamond dicing cutter 51 are parallel through vacuum adsorption, and ensures that there is a constant dicing force and dicing depth during the dicing process. In this embodiment, the adsorption of the vacuum chuck 41 is the prior art, and will not be described in detail.

[0032] Specifically, during the dicing operation, a dedicated film applicator is used to attach the wafer to the wafer ring 9 using a blue film. The wafer ring 9 is then mounted to the wafer mounting mechanism 8 via a magnetic suction device and positioning pin 81. With the wafer facing downwards, the dicing fixing mechanism 4 moves along the upper guide rail 2 to the wafer mounting mechanism 8. The vacuum suction cup 41 adsorbs the blue film, eliminating the wafer's sag caused by gravity and the elasticity of the blue film through vacuum adsorption, keeping the wafer horizontal and ensuring a constant dicing depth. The dicing processing mechanism 5 moves along the lower guide rail 3 to the wafer mounting mechanism 8. The diamond dicing blade 51 is driven by a three-axis linkage mechanism to dice the wafer. After the dicing processing is completed, the vacuum suction cup 41 is turned off, and the dicing fixing mechanism 4 and the dicing processing mechanism 5 move away from the wafer mounting mechanism 8 along the upper and lower guide rails 3, respectively.

[0033] Reference Figure 4 and Figure 5 The cleaving plate fixing mechanism 7 has a detachable cleaving plate disk 71, which is used to set different cleaving plate spacings according to the processing conditions. The cleaving plate disk 71 is fixedly installed on the corresponding z-axis support arm 111 of the cleaving plate fixing mechanism 7 by bolts. Several grooves 711 are equally spaced on the cleaving plate disk 71, and the grooves 711 are set to correspond to the scratches for support during the cleaving plate back pressure process.

[0034] The wafer dicing mechanism 6 has a ceramic dicing blade 61, which is mounted on the z-axis support arm 111z corresponding to the wafer dicing mechanism 6. A force sensor and feedback system are installed on the cutting edge of the ceramic dicing blade 61 to set the pressure parameters according to different materials and to detect the pressure applied by the ceramic dicing blade 61 to the wafer in real time during the dicing process.

[0035] After the dicing process is completed, the dicing mechanism 6 and the dicing fixing mechanism 7 move to the wafer mounting mechanism 8 along the upper guide rail 2 and the lower guide rail 3, respectively. The groove 711 of the dicing disk 71 in the dicing fixing mechanism 7 is aligned with the dicing mark and fed to support the wafer. After the ceramic dicing blade 61 is aligned with the back of the dicing mark, the ceramic dicing blade 61 is fed downward along the guide rail to apply pressure to the back of the dicing mark on the wafer, thus completing the dicing process.

[0036] In this embodiment, the sliding of the dicing and fixing mechanism 4, the dicing processing mechanism 6, the dicing processing mechanism 5 and the dicing and fixing mechanism 7 are all positioned with high precision by a grating ruler displacement sensor (not shown in the figure). Both ends of each linear motor actuator can be equipped with elastic pads to cooperate with the limit block 12 to achieve soft and hard limit to prevent the equipment from malfunctioning. The installation and use of the grating ruler displacement sensor is existing technology and will not be described in detail.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A fixed semiconductor wafer cleaving apparatus, comprising an L-shaped support stage, characterized in that, The support table is provided with upper and lower rails, a wafer fixing mechanism and a wafer scribing mechanism are slidably arranged on the upper rail, a wafer scribing mechanism and a wafer breaking mechanism are slidably arranged on the lower rail, and a wafer mounting mechanism is arranged between the upper and lower rails in the middle of the support table; The wafer mounting mechanism is provided with a rotating shaft for adjusting the wafer scribing direction and a wafer ring for bearing and protecting the wafer, and the wafer mounting mechanism is provided with a magnetic attraction device and a positioning pin for positioning and fixing the wafer ring; The wafer scribing mechanism is provided with a diamond scribing knife for wafer scribing, the diamond scribing knife is provided with a force sensor and a feedback system for setting a constant scribing force, and the wafer scribing mechanism has three degrees of freedom for realizing continuous automatic scribing; the wafer fixing mechanism is provided with a vacuum chuck, the vacuum adsorption ensures that the wafer and the processing track of the diamond scribing knife are parallel, and the wafer fixing mechanism ensures that the scribing force and the scribing depth are constant during the scribing process; The wafer breaking mechanism is provided with a detachable wafer breaking disc for setting different wafer breaking distances according to the processing conditions; the wafer breaking mechanism is provided with a ceramic wafer breaking knife, and the ceramic wafer breaking knife is provided with a force sensor and a feedback system for setting the pressing parameters according to different materials and detecting the pressure applied by the ceramic wafer breaking knife to the wafer in real time during the wafer breaking process.

2. The fixed semiconductor wafer cleaving apparatus according to claim 1, wherein The magnetic attraction device is provided with a flat circular surface, at least one positioning pin is arranged on the flat circular surface, the wafer ring is placed on the flat circular surface by the positioning pin, and the wafer ring is provided with a positioning socket matched with the positioning pin.

3. The fixed semiconductor wafer cleaving apparatus of claim 1, wherein The wafer ring and the wafer are connected by a blue film, and the vacuum chuck adsorbs the blue film to keep the wafer horizontal.

4. The fixed semiconductor wafer cleaving apparatus of claim 1, wherein The wafer scribing mechanism has a three-axis linkage mechanism, the three-axis linkage mechanism is composed of an x-direction moving mechanism, a y-direction moving mechanism and a z-direction moving mechanism, the diamond scribing knife is arranged on the y-direction moving mechanism and driven by the y-direction moving mechanism to move forward and backward, the y-direction moving mechanism is arranged on the z-direction moving mechanism to realize the up-down movement of the diamond scribing knife, and the z-direction moving mechanism is arranged on the x-direction moving mechanism, the x-direction moving mechanism is slidably arranged on the lower rail, and the x-direction moving mechanism realizes the left-right movement of the diamond scribing knife.

5. The fixed semiconductor wafer cleaving apparatus of claim 4, wherein The x-direction moving mechanism includes an x-axis support plate one, and the x-axis support plate one is slidably arranged on the lower rail; the z-direction moving mechanism includes a z-axis guide rail one and a z-axis support plate one, the z-axis guide rail one is arranged on the x-axis support plate one, and the z-axis support plate one is slidably arranged on the z-axis guide rail one; the y-direction moving mechanism includes a y-axis guide rail one and a y-axis support plate one, the y-axis guide rail one is arranged on the z-axis support plate one, and the y-axis support plate one is slidably arranged on the y-axis guide rail one; the x-axis support plate one, the y-axis support plate one and the z-axis support plate one are driven to slide by high-precision linear motors, and the diamond scribing knife is arranged on the y-axis support plate one.

6. The fixed semiconductor wafer cleaving apparatus of claim 5, wherein The diamond scribing knife is arranged on the y-axis support plate one at an angle of 60°.

7. The fixed semiconductor wafer cleaving apparatus of claim 1, wherein The split processing mechanism has a two-axis linkage mechanism, which includes an x-axis moving mechanism and a z-axis moving mechanism, the x-axis moving mechanism has an x-axis support plate two, and the x-axis support plate two is slidably arranged on the upper guide rail; the z-axis moving mechanism has a z-axis support arm and a z-axis guide rail two, the z-axis guide rail two is arranged on the x-axis support plate two, the z-axis support arm is slidably arranged on the z-axis guide rail two, and the ceramic split blade is arranged on the z-axis support arm; the x-axis support plate two and the z-axis support arm are driven to slide by high-precision linear motors.

8. The fixed semiconductor wafer cleaving apparatus of claim 1, wherein The split disc is provided with a plurality of grooves at equal intervals, and the grooves are arranged correspondingly to the scratches and are used for supporting during the split back pressure process.

9. The fixed semiconductor wafer cleaving apparatus of claim 1, wherein The sliding of the scratch fixing mechanism, the split processing mechanism, the scratch processing mechanism and the split fixing mechanism is high-precision positioning through a grating ruler displacement sensor, and soft and hard limit positions are arranged to prevent accidents of the equipment.

Citation Information

Patent Citations

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