Wafer bonding magnetic alignment method and device

Abstract

The present invention discloses a wafer bonding magnetic alignment method and device, the device includes at least an X-Y moving system, a bottom wafer bonding table, a magnetic sensor module, a bonding arm module, a device base and a frame. The method makes an alignment groove on the wafer through a semiconductor processing technology, and deposits a magnetic column of magnetic material in the groove. After magnetization, the magnetic column has a permanent magnetic property. The spatial magnetic field distribution in the wafer magnetic column is detected by a magnetic sensor to find the boundary or center of the magnetic column, thereby realizing the detection of wafer position information. Compared with the traditional optical alignment method, the magnetic sensor does not need to calibrate the position, and the alignment is performed when the distance between the two wafers is in the micron level. After alignment, there is no need to move the alignment again, and direct bonding is performed, which improves the efficiency and accuracy of wafer bonding.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a magnetic alignment method and device for wafer bonding. Background Art

[0002] In recent years, the integrated circuit industry has developed rapidly, and the functional requirements of semiconductor chips have continued to increase. The integrated circuit industry is of great significance to my country's economic development. However, Moore's Law has reached its physical limit. The existing solution is to develop from 2D plane to 3D integration, continuing Moore's Law. Wafer-level bonding is a particularly important link in 3D integration technology. The alignment technology in wafer bonding is closely related to the performance of the output chip. With the continuous progress and development of semiconductor technology, the accuracy of the lines on the wafer is getting higher and higher. High-quality alignment accuracy can avoid problems such as serial and short circuit of the line after bonding caused by the misalignment of the alignment pattern. High-precision interconnection between wafers is an important way to achieve the transformation from 2D plane to 3D integration, and it is an important direction for the development of semiconductor integrated circuits. At present, existing semiconductor equipment manufacturers at home and abroad, such as EVG, SUSS and Beijing Huazhuo Jingke, mostly use optical alignment methods in wafer bonding alignment. Through the cooperation of multiple optical lenses and mobile platforms, the position information of the upper and lower wafers is obtained respectively, and then the alignment between the wafers is completed based on the acquired position information. In this type of optical alignment method, the imaging is clear due to the high magnification of the optical lens. However, the optical lens has a complex structure and is difficult to calibrate. In addition, during optical alignment, the lens needs to cooperate with the mobile system to perform multiple large-stroke displacements, which will cause inevitable errors.

[0003] Patent CN109904105A applied by Yan Meng and others of Yangtze Memory Technologies Co., Ltd. discloses a wafer bonding alignment method. This method detects infrared light emitted by a light source passing through the wafer, and then uses an image sensor to obtain the position information of the alignment marks on the two wafers to complete the alignment. Due to the limited penetration ability of the infrared light source and the certain distance between the two layers of wafers, after the detection light source penetrates the two layers of wafers, the imaging accuracy of the image sensor is insufficient and the position information is not accurate enough. Patent CN 112053985 A applied by Yang Guang and others of Beijing Huazhuo Jingke Technology Co., Ltd. discloses a wafer alignment device and alignment method. The device sets the image sensors on both sides of the wafer, and the upper and lower sides are opposite. The motion system first aligns the bottom wafer, fixes the bottom position, saves the position information, and then aligns the upper wafer with the bottom wafer as the reference. Although the upper and lower image sensors of the device are fixed as one, the position distance between the upper and lower image sensors is large. In order to make the sensor position and alignment accurate, a relatively complicated calibration step is required. This will cause calibration errors, and after alignment, a large stroke movement is required, and it is impossible to determine whether it is aligned after the movement, resulting in inevitable errors. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a wafer bonding magnetic alignment method and device. The method is to make an alignment groove on the wafer through a semiconductor processing technology, and deposit a magnetic column of magnetic material in the groove. After magnetization, the magnetic column has permanent magnetic characteristics. The spatial magnetic field distribution in the wafer magnetic column is detected by a magnetic sensor to find the boundary or center of the magnetic column, thereby realizing the detection of wafer position information. The magnetic sensor may include a GMR sensor, a TMR sensor, etc. The magnetic sensor is a typical MTJ push-pull half-bridge sensor principle. When the external magnetic field induction intensity changes, it will be converted into a change in a certain resistance value in the bridge circuit. The change in resistance value is converted into a change in current and voltage, and the external magnetic field change can be detected in real time. Two wafers to be bonded are placed vertically up and down, and there are wafer alignment marks in the two wafers respectively. The marks are at the same position of the two wafers. The magnetic sensor detects the spatial magnetic field changes of the two wafer alignment marks with different alignment degrees. The change law of the spatial magnetic field is detected in real time through the relative movement between the magnetic sensor and the wafer alignment mark, and the magnetic field data is collected and a mathematical model of the spatial magnetic field is established. When the two wafers are aligned and placed, the superimposed magnetic field reaches a certain special state, and the wafers are in an aligned state at this time. After alignment, the device bonds the two wafers, and then demagnetizes the magnetic column after the bonding is completed. Compared with the traditional optical alignment method, the magnetic sensor of the present invention does not need to be calibrated, and can be aligned when the distance between the two wafers is at the micron level. After alignment, there is no need to move the position again, and direct bonding is performed, which improves the efficiency and accuracy of wafer bonding.

[0005] A wafer alignment device is proposed by using the above method, which at least includes an XY moving system, a bottom wafer bonding stage, a magnetic sensor module, a bonding arm module, a device base and a frame.

[0006] The wafer to be bonded is transferred to the bottom wafer bonding station and bonding arm module through the wafer transfer mechanism. The bottom wafer bonding station clamps the lower wafer that is transported, and the bonding head in the bonding arm module picks up the upper wafer. After the bottom wafer bonding station clamps the wafer, it moves to the set corresponding position. At this time, the position is not accurately aligned. When it moves to a closer distance, due to the presence of wafer alignment marks in the two layers of wafers, the magnetic sensor module can accurately reflect the spatial magnetic field changes of the wafer alignment marks. The relative movement between the magnetic sensor module and the wafer alignment mark can be used to detect the change law of its spatial magnetic field in real time and obtain the center position of the wafer alignment mark. Then use the XY moving system for coarse alignment, and detect the change of the spatial magnetic field at all times. When it is close to the target position, use the fine alignment micro-nano platform for fine alignment. After accurate alignment, use the bonding arm module to complete the bonding between wafers.

[0007] The XY moving system is located on the base and frame of the device and is used for the X-axis and Y-axis movement of the bottom wafer bonding stage to achieve the rough alignment process in the alignment process;

[0008] The bottom wafer bonding platform is arranged above the XY moving system, and cooperates with the XY moving system to realize the bearing and rough alignment of the wafer. The bottom wafer bonding platform is a fixing device for the bottom wafer, and is also a bonding working area between wafers.

[0009] The wafer transfer module is used to transfer the wafer to the bottom wafer bonding stage or the bonding arm module;

[0010] The magnetic sensor module is used to detect the spatial magnetic field emitted by the wafer alignment mark and locate the position information of the wafer alignment mark;

[0011] The bonding arm module is used to clamp the upper wafer and realize the vertical movement of the upper wafer;

[0012] The device base and frame are the frame part of the device, and the main material is granite, which provides good working conditions for the motion alignment part.

[0013] Further, the XY movement system comprises:

[0014] X-axis moving platform, which is composed of a motor, screw and guide rail to achieve micron-level precision movement in the X direction;

[0015] The Y-direction moving platform is composed of a motor, a lead screw and a guide rail to achieve micron-level precision movement in the Y direction;

[0016] A precision alignment micro-nano platform is provided, wherein the precision alignment micro-nano platform is used for alignment and compensation of wafer position information, wherein the position information is obtained by a magnetic sensor.

[0017] Furthermore, the magnetic sensor module comprises:

[0018] A magnetic sensor, which may include a GMR sensor, a TMR sensor, etc., for measuring the magnetic field strength of the alignment mark;

[0019] A magnetic sensor chuck, which is used to clamp the magnetic sensor to ensure that the magnetic sensor is in a normal working position;

[0020] The extension rod can realize detection of different distances of the magnetic sensor and can be used for alignment marks at different positions.

[0021] Furthermore, the bonding arm module comprises:

[0022] A bonding head, which is arranged at the bottom of the bonding arm module, can pick up the wafer transferred by the wafer transfer module and apply bonding pressure to achieve bonding between wafers. The bonding head is provided with a magnetic sensor mounting hole, which can be used for direct alignment in some embodiments;

[0023] The bonding moving mechanism is arranged in the center of the entire device and fixed on the device frame, and realizes high-precision movement in the vertical direction through the cooperation of the motor lead screw guide rail.

[0024] The above technical solution of the present invention has the following beneficial effects:

[0025] The present invention introduces a novel magnetic alignment method for wafer bonding, establishes micro-magnetic column alignment marks on the surface of the wafer, detects the spatial magnetic field distribution in the wafer magnetic column through a magnetic sensor, and realizes the detection of wafer position information. Compared with the traditional optical alignment method, the present invention has low sensor calibration difficulty and improves the efficiency of wafer alignment. The traditional optical alignment method requires a large displacement stroke, which will cause position error. The present invention can realize real-time detection of wafer position, reduce the error caused by large displacement stroke, facilitate sensor position calibration, and improve the efficiency and alignment accuracy of wafer alignment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A flowchart of an alignment method of an embodiment of a wafer alignment device of the present invention;

[0027] Figure 2 A flowchart of an alignment method of another embodiment of a wafer alignment device of the present invention;

[0028] Figure 3 A schematic diagram of the shapes of some wafer alignment marks of the wafer alignment device of the present invention, and the spatial magnetic density distribution corresponding to wafer alignment marks of different shapes of a single target;

[0029] Figure 4 The alignment detection principle of an embodiment of the wafer alignment device of the present invention, including a schematic diagram of the alignment structure and the spatial magnetic field distribution of overlapping alignment marks;

[0030] Figure 5 An embodiment of an alignment method of a wafer alignment device of the present invention;

[0031] Figure 6 Another embodiment of the alignment method of the wafer alignment device of the present invention is provided;

[0032] Figure 7 A three-dimensional diagram of a wafer alignment device of the present invention;

[0033] Figure 8 The invention discloses a magnetic sensor array detection module for a wafer alignment device.

[0034] 1. XY moving system, 2. X-axis moving platform, 3. Y-axis moving platform, 4. Precision alignment micro-nano platform, 5. Bottom wafer bonding stage, 6. Wafer transfer module, 7. Magnetic sensor module, 8. Magnetic sensor, 9. Magnetic sensor chuck, 10. Extension rod, 11. Upper wafer, 12. Lower wafer, 13. n-th layer wafer, 14. Upper wafer alignment mark, 15. Lower wafer alignment mark, 16. n-layer wafer alignment mark, 17. Bonding arm module, 18. Bonding head, 19. Bonding moving mechanism, 20. Cylindrical alignment mark, 21. Rectangular alignment mark, 22. Device base and frame. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiment of the present invention. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0036] The following is a detailed description of the wafer bonding magnetic alignment method and device according to an embodiment of the present invention in conjunction with the accompanying drawings. Figures 7 and 8 As shown, the wafer bonding magnetic alignment device according to the example of the present invention specifically includes: an XY moving system 1, a bottom wafer bonding stage 5, a magnetic sensor module 7, a bonding arm module 17, a device base and a frame 22.

[0037] Specifically, the working process of the wafer bonding magnetic alignment method in one embodiment of the present invention is shown in Figure 1 The figure only shows the alignment method and principle of one alignment mark, and the other alignment marks are aligned in the same way. Figure 1 As shown in , the alignment step is mainly divided into four steps:

[0038] Step 1: First, use the XY moving system 1 to move the bottom wafer bonding stage 5 that has picked up the lower wafer 12 to a pre-set position. At the same time, the bonding head 18 in the bonding arm module 17 also picks up the upper wafer 11 at the same time. At this time, alignment has not yet begun. Step 2: In this embodiment, the magnetic sensor module 7 is set between the upper wafer 11 and the lower wafer 12 and distributed on both sides. Two magnetic sensor 8 clamps are used to clamp the upper and lower different magnetic sensors 8 respectively. The upper magnetic sensor 8 is first used to detect the wafer alignment mark position information in the upper wafer 11, and the acquired position information is collected and recorded. Then the lower magnetic sensor 8 is used to detect the wafer alignment mark position information in the lower wafer 12. Due to the position difference between the upper wafer 11 and the lower wafer 12, the XY moving system 1 is used for rough alignment, and then the micro-nano platform 4 is used for fine alignment to achieve high-precision alignment. Step 3: After the alignment is completed, the bonding arm module 17 is used to perform bonding movement to achieve bonding between the upper wafer 11 and the lower wafer 12. Step 4: As shown in the figure, the alignment method of step 2 is continued to be repeated to align the n-th layer wafer 13, and the position information of the n-th layer wafer alignment mark 16 is continued to be detected to complete the alignment and bonding. The advantage of this embodiment is that the bonding accuracy after the last alignment can be detected, and feedback and adjustment of the next bonding can be performed according to the position error after bonding.

[0039] See also Figure 5 and Figure 3 , which is an alignment embodiment of the alignment mark spatial magnetic field curve diagram and wafer alignment device in the present invention.

[0040] The alignment method is arranged as follows Figure 5 As shown, the upper wafer 11 has been transferred to the bonding head 18 in the bonding arm module 17 through the transfer module, and the bottom wafer bonding table 5 has also picked up the transferred lower wafer 12. At this time, the upper and lower wafers 12 have been moved to the pre-designed positions through the XY moving system 1, and alignment has not been performed yet. At the same time, the magnetic sensor module 7 is arranged between the upper wafer 11 and the lower wafer 12 in the vertical direction and on both sides thereof in the horizontal direction to provide preparation for wafer alignment.

[0041] Further, the alignment principle and alignment marks in this embodiment refer to Figure 3 As shown in Figure 2, two geometric models of alignment marks are listed. Figure 3The middle left figure is the spatial magnetic density curve of the cylindrical alignment mark 20. It can be seen from the figure that the spatial magnetic density distribution of the cylindrical alignment mark 20 has experienced two peak values ​​and one trough value. The main purpose of this embodiment is alignment, that is, using the spatial magnetic density curve of the alignment mark to find its center position. Analysis shows that the center position of the trough value is the center of the cylindrical alignment mark 20, but the trough value at the center changes relatively slowly, and it is not easy to find its center position. The present invention uses the positions of the two peak values ​​to be symmetrically distributed on both sides of the trough center, and obtains the center position of the cylindrical alignment mark 20 by the average value method.

[0042] Similarly, Figure 3 The middle right figure is the spatial magnetic density curve of the rectangular alignment mark 21. It can be seen from the figure that the spatial magnetic density distribution of the rectangular alignment mark 21 has experienced two peak values ​​and one uneven trough value. Analysis shows that the center position of the trough value is the center of the rectangular alignment mark 21. The present invention uses the symmetrical distribution of the positions of the two peak values ​​about the center of the trough to obtain the center position of the rectangular alignment mark 21 by the average value method.

[0043] The alignment mark model in the present invention is not limited to the cylindrical alignment mark 20 and the rectangular alignment mark 21 in the examples.

[0044] The working process of the wafer bonding magnetic alignment method in another embodiment of the present invention is shown in Figure 2 The figure only shows the alignment method and principle of one alignment mark, and the other alignment marks are aligned in the same way. Figure 2 As shown, the alignment step is mainly divided into four steps:

[0045] Step 1: First, use the bonding head 18 in the bonding arm module 17 to pick up the upper wafer 11. The bonding head 18 is provided with a magnetic sensor 8. When the upper wafer 11 is picked up, the spatial magnetic field distribution of the upper wafer alignment mark 14 embedded in the upper wafer 11 can be detected to obtain the position information of the upper wafer 11; Step 2: Use the XY moving system 1 to move the bottom wafer bonding table 5 that has picked up the lower wafer 12 to a pre-set position. At this time, the bonding head 18 in the bonding arm module 17 has picked up the upper wafer 11, and the magnetic sensor 8 in the bonding head 18 has obtained the position information of the alignment mark of the upper wafer 11, and the obtained position information is collected and recorded. Step 3: Use the XY moving system 1 again for rough alignment, and use the magnetic sensor 8 in the bonding head 18 to detect the distribution of the superimposed spatial magnetic field when the two wafer alignment marks are coaxially placed in the vertical direction, and obtain the position information of the alignment mark of the lower wafer 12. Then, high-precision alignment is achieved through the fine alignment micro-nano platform 4. After alignment is completed, the bonding arm module 17 performs bonding movement to achieve bonding between the upper wafer 11 and the lower wafer 12. Step 4: Continue to repeat the alignment method of steps 1 and 2 to align the n-th layer wafer 13, and continue to detect the position information of the n-th layer wafer alignment mark 16 to complete alignment and bonding.

[0046] See also Figure 6 and Figure 4 , is a spatial magnetic field curve diagram of a wafer alignment mark and a schematic diagram of an alignment device in another embodiment of the present invention.

[0047] The alignment method is arranged as follows Figure 6 As shown, similarly, the upper wafer 11 has been transferred to the bonding head 18 in the bonding arm module 17 through the transmission module, and the bottom wafer bonding table 5 has also picked up the transferred lower wafer 12. At this time, the upper and lower wafers 12 have been moved to the pre-designed positions through the XY moving system 1, and alignment has not been performed at this time. In this embodiment, the magnetic sensor 8 is arranged in the bonding head 18 in the bonding arm module 17, which can detect the position information of the alignment mark in the upper wafer 11 in real time, and provide preparation for wafer alignment.

[0048] Further, the alignment principle and alignment structure diagram in this embodiment can be found in Figure 4 As shown. The figure shows the spatial magnetic field distribution when two wafer alignment marks are placed coaxially in the vertical direction. It can be seen from the figure that the spatial magnetic flux density distribution of the cylindrical alignment marks 20 spaced apart and placed coaxially in the upper and lower positions is the same as that of a single cylindrical alignment mark 20, and has experienced two peak values ​​and one trough value. However, the size of the peak value has changed significantly, that is, the spatial magnetic fields of the two cylindrical alignment marks 20 are superimposed on each other to enhance the spatial magnetic flux density. Similarly, the present invention uses the symmetrical distribution of the positions of the two peak values ​​about the center of the trough, and obtains the center position of the cylindrical alignment mark 20 by the average value method.

[0049] The three-dimensional diagram of the wafer alignment device of the present invention is shown in Figure 7 The XY moving system 1 is arranged on the device base and frame 22, and is mainly composed of a high-precision lead screw guide rail and a motor. By using the XY two-layer superposition method, the X-axis and Y-axis of the bottom wafer bonding stage 5 are moved to realize the rough alignment process in the wafer alignment. The bottom wafer bonding stage 5 is arranged on the XY moving system 1, and is connected to the bottom wafer bonding stage 5 through the slider on the guide rail. The bottom wafer bonding stage 5 is mainly the bonding area of ​​the upper wafer 11 and the lower wafer 12, which can fix the wafer transferred by the wafer transmission module 6. At the same time, a fine alignment micro-nano platform 4 is provided on both sides of the XY of the bottom wafer bonding stage 5, which can realize high-precision alignment during the wafer alignment process, and is used for alignment and compensation of wafer position information, wherein the position information is obtained by the magnetic sensor 8. The sensor module is arranged between the upper wafer 11 and the lower wafer 12, and is mainly composed of a magnetic sensor 8, a magnetic sensor chuck 9 and an extension rod 10. In some embodiments, the magnetic sensor module 7 is also disposed in the bonding head 18 of the bonding arm module 17. The bonding arm module 17 is disposed above the entire device. To enable a smooth bonding movement, the bonding arm module 17 is fixed to the device base and the frame 22. The bonding head 18 moves only in the Z direction through the cooperation of a high-precision motor and a guide rail.

[0050] Furthermore, the magnetic sensor 8 may include a GMR sensor, a TMR sensor, etc., to measure the magnetic field strength of the alignment mark.

[0051] Further, Figure 8 A magnetic sensor 8 array detection module for the wafer alignment device and method of the present invention is shown in the figure as a 3x3 magnetic sensor 8 rectangular array. The magnetic sensor 8 shown in the figure is arranged in the bonding head 18, which is suitable for the second embodiment. The advantage of the magnetic sensor 8 array detection module is that it can improve the detection accuracy of the magnetic sensor 8 and maximize the detection accuracy of the wafer alignment mark.

[0052] The present invention proposes a novel magnetic alignment method for wafer bonding, establishes micro-magnetic column alignment marks on the surface of the wafer, detects the spatial magnetic field distribution in the wafer magnetic column through a magnetic sensor, and realizes the detection of wafer position information. Compared with the traditional optical alignment method, the present invention has low sensor calibration difficulty and greatly improves the efficiency of wafer alignment. The traditional optical alignment method requires a large displacement stroke, which will cause position error. The present invention can realize real-time detection of wafer position, reduce the error caused by large-stroke movement, facilitate sensor position calibration, and improve the efficiency and alignment accuracy of wafer alignment. At the same time, the present invention can detect the bonding accuracy after the last alignment, and perform the next bonding based on the position error feedback and adjustment after bonding, thereby improving the alignment accuracy when aligning multi-layer wafers.

[0053] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A wafer alignment device, characterized in that: Includes XY motion system, bottom wafer bonding stage, magnetic sensor module, bonding arm module, device base and frame; The wafer to be bonded is transferred to the bottom wafer bonding table and bonding arm module through the wafer transfer mechanism; the bottom wafer bonding table clamps the lower wafer that is transferred, and the bonding head in the bonding arm module picks up the upper wafer; the bottom wafer bonding table clamps the wafer and moves to the set position, and the position is not accurately aligned at this time; when it moves to a closer distance, since there are wafer alignment marks in the two layers of wafers, the magnetic sensor module can accurately reflect the spatial magnetic field changes of the wafer alignment marks, and the change law of the spatial magnetic field is detected in real time through the relative movement between the magnetic sensor module and the wafer alignment mark to obtain the center position of the wafer alignment mark; the XY moving system is used for coarse alignment, and the spatial magnetic field changes are detected at the same time. When approaching the target position, the fine alignment micro-nano platform is used for fine alignment. After accurate alignment, the bonding between the wafers is completed using the bonding arm module; The XY moving system is located on the base and frame of the device and is used for the X-axis and Y-axis movement of the bottom wafer bonding stage to achieve the rough alignment process in the alignment process; The bottom wafer bonding platform is arranged above the XY moving system, and cooperates with the XY moving system to realize the bearing and rough alignment of the wafer. The bottom wafer bonding platform is a fixing device for the bottom wafer, and is also a bonding working area between wafers. The magnetic sensor module is used to detect the spatial magnetic field emitted by the wafer alignment mark and locate the position information of the wafer alignment mark; The XY movement system includes: X-axis moving platform, which is composed of a motor, screw and guide rail to achieve micron-level precision movement in the X direction; The Y-direction moving platform is composed of a motor, a lead screw and a guide rail to achieve micron-level precision movement in the Y direction; A precision alignment micro-nano platform, which is used for alignment and compensation of wafer position information, wherein the position information is obtained by a magnetic sensor; The magnetic sensor module comprises: A magnetic sensor, comprising a GMR sensor and a TMR sensor, for measuring the magnetic field strength of the alignment mark; A magnetic sensor chuck, which is used to clamp the magnetic sensor to ensure that the magnetic sensor is in a working position; An extension rod, which enables the magnetic sensor to detect different distances and can be used for alignment marks at different positions; The bonding arm module comprises: The bonding head is arranged at the bottom of the bonding arm module, picks up the wafer transferred by the wafer transfer module, and applies bonding pressure to achieve bonding between wafers. The bonding head is provided with a magnetic sensor mounting hole for direct alignment; The bonding moving mechanism is arranged in the center of the entire device and fixed on the device frame, and realizes high-precision movement in the vertical direction through the cooperation of the motor lead screw guide rail.

2. A wafer alignment device according to claim 1, characterized in that: The wafer transfer mechanism is used to transfer the wafer to the bottom wafer bonding stage or the bonding arm module.

3. A wafer alignment device according to claim 1, characterized in that: The bonding arm module is used to clamp the upper wafer and realize the vertical movement of the upper wafer.

4. The wafer alignment device according to claim 1, characterized in that: The device base and frame are the frame part of the device.

Images