A device for detecting uniformity of adsorption force of an electrostatic chuck for semiconductor wafers

Abstract

The present invention relates to an adsorption force uniformity detection device for an electrostatic chuck for semiconductor wafers applied in the semiconductor field. The device first simulates an adsorbed workpiece through a passive adsorption film, then rotates and scans the passive adsorption film through an adsorption force scanning component, and reversely adsorbs the passive adsorption film during the scanning process. A distributed sensing optical fiber is used to identify areas that are raised by reverse adsorption due to insufficient adsorption force, and this area is directly fed back to the outside through a positioning member, thereby achieving intuitive positioning of the area with insufficient adsorption force, which is convenient for detection personnel to make adjustments later. While scanning, the surface flatness of the electrostatic chuck is also detected through a flatness scanning component. When the electrostatic chuck is significantly deformed due to heat, it can be detected and located in time, effectively preventing the electrostatic chuck from affecting the processing accuracy of the wafer.

Description

Technical Field

[0001] The present invention relates to a device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer, and in particular to a device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer applied in the semiconductor field. Background Art

[0002] The working principle of an electrostatic chuck is based on Coulomb's law and Lorentz's law, securing the workpiece through electrostatic adsorption. Uneven adhesion of the electrostatic chuck directly affects the precision and yield of the wafer. Insufficient adhesion can cause wafer movement and affect processing accuracy. Therefore, the uniformity of the electrostatic chuck's adhesion should be regularly tested.

[0003] There are means of detecting the uniformity of the adsorption force of an electrostatic chuck in the prior art, such as a semiconductor wafer electrostatic chuck adsorption force detection device and detection method with publication number CN118424532B, which discloses the adsorption force is inferred by the flow change in the cooling channel inside the chuck. Although online detection can be achieved, it can only perform partitioned detection and cannot locate uneven areas. Moreover, it needs to rely on complex models and is prone to large errors. There is also a tool for detecting the adsorption force of an electrostatic adsorption disk with publication number CN221147916U, which discloses a technical means of embedding a micro pressure sensor in a workpiece simulating a wafer to test the adsorption force, but it cannot yet locate the uneven area.

[0004] Although there are many methods for testing the uniformity of electrostatic adsorption force in the prior art, it is impossible to intuitively locate the area with uneven adsorption force. The tester can only know the approximate location of the uneven area, which requires multiple adjustments and has low work efficiency. Summary of the Invention

[0005] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is how to detect the position where the adsorption force of the electrostatic chuck is uneven and to express the uneven area intuitively.

[0006] To solve the above problems, the present invention provides a device for detecting the uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer, comprising an electrostatic chuck and a transparent detection cover covering the electrostatic chuck, wherein the transparent detection cover is provided with a detection cavity with an opening facing downward, and a passive adsorption film that is in contact with the electrostatic chuck is fixedly connected to the inner wall of the detection cavity, a driving motor is installed in the middle of the upper end of the transparent detection cover, and a driving shaft connected to the output end of the driving motor is installed inside the detection cavity, the bottom end of the driving shaft is fixedly connected to an adsorption force scanning component that is in contact with the passive adsorption film, and the driving shaft is fixedly connected to a positioning member at the upper end of the adsorption force scanning component, and a force-induced chromic film that is in contact with the upper end of the transparent detection cover is fixedly connected to the inner wall of the upper end of the detection cavity;

[0007] The adsorption force scanning component includes a smoothing seat, an electromagnetic absorption plate fixedly connected to one side of the smoothing seat in the forward direction, and a distributed sensing optical fiber 1 placed directly below the electromagnetic absorption plate. A groove is provided on the side wall of the smoothing seat near the electromagnetic absorption plate. Both ends of the distributed sensing optical fiber 1 are fixedly connected to support arms extending into the interior of the groove, and the two support arms are simultaneously rotatably connected to the inner wall of the groove. A rotating column is fixedly connected between the upper ends of the two support arms, and the inner wall of the groove is fixedly connected to a rotation angle detection seat that is concentric with the rotation center of the support arm, and the outer surface of the rotation angle detection seat is fixedly inlaid with a conductive sheet, and a wire perpendicular to the conductive sheet is fixedly inlaid on the rotating column. The conductive sheet and the wire together constitute a conduction circuit, and a current detection device connected to the conduction circuit is installed inside the smoothing seat. A master control processor connected to the signal of the distributed sensing optical fiber 1 is also installed on the smoothing seat, and the master control processor is connected to the signal of the positioning piece;

[0008] The passive adsorption film includes an electrostatic adsorption layer adhered to the electrostatic suction cup, a frictionless scanning layer adhered to the adsorption force scanning component, and a magnetic absorption layer located between the electrostatic adsorption layer and the frictionless scanning layer. When the electromagnetic absorption plate is energized, it generates suction on the magnetic absorption layer, and the maximum magnetic attraction force of the electromagnetic absorption plate on the magnetic absorption layer is less than the electrostatic adsorption force when the electrostatic suction cup is working.

[0009] In the above-mentioned electrostatic chuck adsorption force uniformity detection device for semiconductor wafers, the electrostatic chuck is scanned by the adsorption force scanning component. During the scanning process, the area with insufficient adsorption force is scanned out, and the positioning part is used to intuitively locate the area with insufficient adsorption force, which is convenient for the detection personnel to make adjustments later. In addition, the flatness of the electrostatic chuck can also be detected during the scanning process, effectively preventing the uneven deformation of the electrostatic chuck surface from affecting the wafer processing accuracy.

[0010] As a further improvement of the present application, the magnetic absorption layer is made of a flexible magnetic material, and the frictionless scanning layer is made of a flexible smooth material.

[0011] As a further improvement of the present application, the positioning member includes a follower seat, and a plurality of equally spaced sliding grooves are provided on the upper side wall of the follower seat, and an electromagnet connected to the signal of the master control processor is installed at the bottom of the sliding groove, a magnetic top block is slidably connected inside the sliding groove, and the electromagnet generates a repulsive force on the magnetic top block when energized, and a plurality of symmetrically distributed elastic bands are fixedly connected between the bottom of the magnetic top block and the electromagnet.

[0012] As a further improvement of the present application, the outside of the distributed sensing optical fiber 1 is wrapped with an anti-wear sleeve, and the anti-wear sleeve is made of a flexible and smooth material.

[0013] As another improvement of the present application, the upper ends of the two support arms are both straight sections, and the straight sections of the support arms abut against the inner wall of the upper end of the groove.

[0014] As another improved supplement of the present application, an alarm is also installed on the transparent detection cover, and the alarm is connected to the current detection device signal.

[0015] As another improved supplement to the present application, a clearance groove is provided on the lower side wall of the smoothing seat, and a flatness scanning assembly is fixedly connected in the clearance groove. The flatness scanning assembly includes a fixed seat, and a plurality of guide grooves with openings facing downward and distributed at equal intervals are provided on the fixed seat. A plane sensing head perpendicular to the passive adsorption membrane is slidably connected in each guide groove, and a fixed plate is fixedly connected to the upper end of the plane sensing head. A perforation is provided in the middle of each fixed plate, and the centers of the perforations on all the fixed plates are on the same straight line. The flatness scanning assembly also includes a distributed sensing optical fiber 2, and the distributed sensing optical fiber 2 passes through the perforation. An elastic pad is fixedly connected between the upper end of each fixed plate and the upper inner wall of the clearance groove. The distributed sensing optical fiber 2 is connected to the electromagnet signal through the master control processor.

[0016] As another improvement of the present application, an anti-wear pad is fixedly connected to the bottom of the planar contact head, and the anti-wear pad is made of a wear-resistant and smooth material.

[0017] In summary, a passive adsorption film is first used to simulate the adsorbed workpiece, and then the passive adsorption film is rotated and scanned by the adsorption force scanning component. During the scanning process, the passive adsorption film is sucked back, and a distributed sensing optical fiber is used to identify the area that is sucked back due to insufficient adsorption force, and this area is directly fed back to the outside through the positioning part, so as to achieve intuitive positioning of the area with insufficient adsorption force, which is convenient for the inspection personnel to make adjustments later. While scanning, the surface flatness of the electrostatic chuck is also inspected by the flatness scanning component. When the electrostatic chuck is greatly deformed due to heat, it can be detected and positioned in time, effectively preventing the electrostatic chuck from affecting the processing accuracy of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a three-dimensional diagram of the transparent detection cover according to the first embodiment of the present application;

[0019] Figure 2 This is a three-dimensional disassembled diagram of the transparent detection cover according to the first embodiment of the present application;

[0020] Figure 3 This is a front cross-sectional view of the transparent detection cover according to the first embodiment of the present application;

[0021] Figure 4 This is a three-dimensional exploded view of the passive adsorption membrane of the first embodiment of the present application;

[0022] Figure 5 This is a three-dimensional diagram of the adsorption force scanning component of the first embodiment of the present application;

[0023] Figure 6 1. A side cross-sectional view of the adsorption force scanning assembly according to the first and second embodiments of the present application;

[0024] Figure 7 This is a side cross-sectional view of the adsorption force scanning assembly according to the first embodiment of the present application when an area with insufficient adsorption force is detected;

[0025] Figure 8 This is a side cross-sectional view of the adsorption force scanning assembly of the first embodiment of the present application when crossing an area with insufficient adsorption force;

[0026] Figure 9 This is a state diagram of the distributed sensing optical fiber 1 during scanning according to the first embodiment of the present application;

[0027] Figure 10 This is a state diagram of the distributed sensing optical fiber 1 according to the first embodiment of the present application when crossing an area with insufficient adsorption force;

[0028] Figure 11 This is a side cross-sectional view of a distributed sensing optical fiber according to the first embodiment of the present application;

[0029] Figure 12 This is a front cross-sectional view of a flatness scanning assembly according to a second embodiment of the present application;

[0030] Figure 13 This is a side sectional view of the flatness scanning assembly according to the second embodiment of the present application.

[0031] Description of the numbers in the figure:

[0032] 1 Electrostatic suction cup, 2 Transparent detection cover, 3 Passive adsorption film, 301 Electrostatic adsorption layer, 302 Magnetic repulsion layer, 303 Frictionless scanning layer, 4 Drive motor, 5 Adsorption force scanning assembly, 501 Smoothing seat, 502 Electromagnetic repulsion plate, 503 Distributed sensing optical fiber 1, 5031 Anti-wear sleeve, 504 Support arm, 505 Follow-up column, 506 Rotation angle detection seat, 6 Positioning parts, 601 Follow-up seat, 602 Electromagnet, 603 Magnetic top block, 604 Elastic belt, 7 Mechanochromic film, 8 Flatness scanning assembly, 801 Fixed seat, 802 Plane sensing contact head, 8021 Anti-wear pad, 803 Fixed plate, 804 Distributed sensing optical fiber 2, 805 Elastic pad. DETAILED DESCRIPTION

[0033] Two implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0034] The first implementation method:

[0035] like Figure 1 、 Figure 2 、 Figure 3As shown, a device for detecting the uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer is provided, comprising an electrostatic chuck 1, a transparent detection cover 2 covering the electrostatic chuck 1, the transparent detection cover 2 being provided with a detection cavity with an opening facing downward, and a passive adsorption film 3 in contact with the electrostatic chuck 1 being fixedly connected to the inner wall of the detection cavity, a driving motor 4 (which is the existing technology, and the specific model is selected according to actual needs) is installed in the middle of the upper end of the transparent detection cover 2, and a driving shaft connected to the output end of the driving motor 4 is installed inside the detection cavity, the bottom end of the driving shaft is fixedly connected to an adsorption force scanning component 5 in contact with the passive adsorption film 3, and the driving shaft is located above the adsorption force scanning component 5 The end is fixedly connected with a positioning piece 6, and the inner wall of the upper end of the detection cavity is fixedly connected with a force-induced chromic film 7 (made of force-induced chromic material) that is in contact with the upper end of the transparent detection cover 2. During the detection, the transparent detection cover 2 is placed on the electrostatic chuck 1, and the bottom of the transparent detection cover 2 is placed on the base of the electrostatic chuck 1. The passive adsorption film 3 is in contact with the upper surface of the electrostatic chuck 1. When the electrostatic chuck 1 is started, the passive adsorption film 3 is adsorbed on the upper surface of the electrostatic chuck 1. When the detection work is started, the drive motor 4 is started to drive the adsorption force scanning component 5 and the positioning piece 6 to scan the passive adsorption film 3, thereby realizing the detection of the uniformity of the adsorption force of the electrostatic chuck 1;

[0036] like Figure 5 、 Figure 6As shown, the adsorption force scanning component 5 includes a smoothing seat 501 (made of smooth material), an electromagnetic reflection absorption plate 502 (made of electromagnetic material) fixedly connected to one side of the smoothing seat 501 in the forward direction, and a distributed sensing optical fiber 503 placed directly below the electromagnetic reflection absorption plate 502 (which is the existing technology, and the specific structural composition and working principle are well-known technologies for technical personnel in the relevant field, and will not be described in detail here). The smoothing seat 501 is provided with a groove on the side wall near the electromagnetic reflection absorption plate 502, and both ends of the distributed sensing optical fiber 503 are fixedly connected to support arms 504 extending into the interior of the groove, and the two support arms 504 are simultaneously rotatably connected to the inner wall of the groove, and a rotating column 505 is fixedly connected between the upper ends of the two support arms 504, and a rotation angle detection seat 506 is fixedly connected to the inner wall of the groove, which is concentric with the rotation center of the support arm 504, and the outer surface of the rotation angle detection seat 506 is fixedly inlaid with a conductive sheet (which itself has a certain Resistance), a wire perpendicular to the conductive sheet is fixedly embedded on the rotating column 505, and the conductive sheet and the wire together form a conductive circuit, and a current detection device connected to the conductive circuit is installed inside the smoothing seat 501 (which is the existing technology, and the specific model is selected according to actual needs), and an alarm is also installed on the transparent detection cover 2 (which is the existing technology, and the specific model is selected according to actual needs), and the alarm is signal-connected to the current detection device, and a master control processor connected to the distributed sensing optical fiber 503 is also installed on the smoothing seat 501, and the master control processor is signal-connected to the positioning member 6 (the specific structure and control principle of the electrical connection in this part are well-known technologies to technicians in the relevant field and will not be described in detail here). When starting the detection work, the electromagnetic anti-absorption plate 502 is first energized, and the electromagnetic anti-absorption plate 502 generates an upward suction force on the passive adsorption film 3, and the drive motor 4 drives the adsorption force scanning component 5 to rotate to scan the electrostatic suction cup 1, such as Figure 7 As shown, during the rotation process, if the adsorption force of a certain part of the electrostatic suction cup 1 is insufficient, the passive adsorption film 3 at this place is sucked up by the electromagnetic repulsion plate 502. At this time, the passive adsorption film 3 is separated from the electrostatic suction cup 1 and bulges upward. The distributed sensing optical fiber 1 503 touches the bulge during the rotation scanning process and is deformed. The distributed sensing optical fiber 1 503 sends the deformed position to the main control processor. The main control processor first pauses the rotation of the adsorption force scanning component 5, and then starts the electromagnet 602 located above the bulge. The electromagnet 602 is energized to generate a repulsive force on the magnetic top block 603. The magnetic top block 603 presses on the force-induced chromic film 7, and the force-induced chromic film 7 changes color under the force. The inspection personnel can intuitively know the area where the adsorption force of the electrostatic suction cup 1 is insufficient by the color change of the force-induced chromic film 7, and can use a marker to mark the discolored area of ​​the force-induced chromic film 7 on the transparent inspection cover 2 to facilitate the corresponding adjustment later. After the marking is completed, the drive motor 4 is started to continue to make the adsorption force scanning component 5 rotate and scan. Figure 8As shown, when the distributed sensing optical fiber 1 503 crosses the protrusion, the support arm 504 drives the rotating column 505 to rotate a certain angle, as shown in FIG. Figure 9 、 Figure 10 As shown, before the support arm 504 rotates, the wire on the rotating column 505 and the conductive sheet on the rotation angle detection seat 506 form a conductive path, and the voltage in the conductive circuit is constant. At this time, the current detection device can measure a current value, and when the rotating column 505 rotates, the current detection device measures another current value. The two current values ​​before and after increase in the length of the rotation angle detection seat 506 increase the resistance. Therefore, after the rotating column 505 rotates, the resistance increases and the current value decreases. When the measured current value is less than the preset threshold value, it indicates that the higher the protrusion of the passive adsorption film 3 is, the more indirectly it indicates that the adsorption force here is seriously insufficient. The current detection device triggers the alarm to send a warning signal to the detection personnel, which is convenient for subsequent key processing.

[0037] like Figure 11 As shown, the distributed sensing optical fiber 1 503 is wrapped with an anti-wear sleeve 5031, and the anti-wear sleeve 5031 is made of a flexible and smooth material. Since the distributed sensing optical fiber 1 503 is pushed and slid on the passive adsorption film 3, in order to prevent the distributed sensing optical fiber 1 503 from being worn and to prevent friction from hindering its movement, the anti-wear sleeve 5031 is put on its outer surface for protection;

[0038] like Figure 9 As shown, the upper ends of the two support arms 504 are both straight sections, and the straight sections of the support arms 504 abut against the upper inner wall of the groove. When the distributed sensing optical fiber 1 503 rotates and slides on the passive adsorption film 3, in order to prevent the distributed sensing optical fiber 1 503 from rotating downward due to friction resistance during the forward movement, thereby hindering the scanning detection work, the upper inner wall of the groove is used to limit the downward rotation of the distributed sensing optical fiber 1 503;

[0039] like Figure 3As shown, the positioning member 6 includes a follower seat 601, and the upper side wall of the follower seat 601 is provided with a plurality of equally spaced sliding grooves, and an electromagnet 602 connected to the master control processor signal is installed at the bottom of the sliding groove, a magnetic top block 603 is slidably connected inside the sliding groove, and the electromagnet 602 generates a repulsive force on the magnetic top block 603 when energized, and a plurality of symmetrically distributed elastic bands 604 are fixedly connected between the bottom of the magnetic top block 603 and the electromagnet 602. When the distributed sensing optical fiber 1 503 scans a protrusion on the passive adsorption film 3, the master control processor energizes the electromagnet 602 located just above the protrusion, causing it to repel the magnetic top block 603, and the magnetic top block 603 presses on the mechanochromic film 7 to change color, thereby intuitively displaying the area with insufficient adsorption force. After the electromagnet 602 is turned off, the elastic force of the elastic band 604 resets the magnetic top block 603. At this time, the mechanochromic film 7 loses pressure and returns to its original color, which is convenient for continuing to mark the protrusion during subsequent scanning.

[0040] like Figure 4 As shown, the passive adsorption film 3 includes an electrostatic adsorption layer 301 adhered to the electrostatic suction cup 1, a frictionless scanning layer 303 adhered to the adsorption force scanning component 5, and a magnetic absorption layer 302 located between the electrostatic adsorption layer 301 and the frictionless scanning layer 303. The magnetic absorption layer 302 is made of a flexible magnetic material, and the frictionless scanning layer 303 is made of a flexible smooth material. When the electromagnetic absorption plate 502 is energized, it generates an attraction on the magnetic absorption layer 302, and the maximum magnetic attraction force of the electromagnetic absorption plate 502 on the magnetic absorption layer 302 is less than the electrostatic adsorption force of the electrostatic suction cup 1 when it is working. During the detection process, the electrostatic adsorption layer 301 is adsorbed on the electrostatic suction cup 1 due to the static electricity, and the distributed sensing optical fiber 1 503 slides on the frictionless scanning layer 303. When the electromagnetic absorption plate 502 is energized, it generates an attraction on the magnetic absorption layer 302, and The suction force of the electromagnetic absorption plate 502 on the magnetic absorption layer 302 is less than the electrostatic adsorption force. If the electrostatic adsorption force of the electrostatic suction cup 1 on the passive adsorption film 3 remains unchanged, the passive adsorption film 3 remains in close contact with the electrostatic suction cup 1. If the adsorption force of the electrostatic suction cup 1 is insufficient, the passive adsorption film 3 will be attracted by the electromagnetic absorption plate 502 and bulge upward, and then the distributed sensing optical fiber 503 will detect that the adsorption force of the electrostatic suction cup 1 is uneven. In addition, it should be additionally explained that the value of the suction force of the electromagnetic absorption plate 502 on the passive adsorption film 3 is less than the adsorption force of the electrostatic suction cup 1 on the passive adsorption film 3 is determined according to the specific size of the electrostatic adsorption force. It can be 1 Newton less, or 2 Newtons less or more, with the standard being that the passive adsorption film 3 can be obviously bulged and detected by the distributed sensing optical fiber 503. No specific value is set here.

[0041] In this embodiment, the passive adsorption film 3 is first used to simulate the adsorbed workpiece, and then the passive adsorption film 3 is rotationally scanned by the adsorption force scanning component 5. During the scanning process, the passive adsorption film 3 is reversely adsorbed, and the distributed sensing optical fiber 503 is used to identify the area that is reversely adsorbed due to insufficient adsorption force, and this area is directly fed back to the outside through the positioning member 6. Compared with the existing technology, this embodiment can achieve intuitive positioning of the area with insufficient adsorption force, which is convenient for the inspection personnel to make adjustments later, and there is no need to deploy multiple sensors for detection. It saves costs and does not damage the surface structure of the electrostatic suction cup.

[0042] Second implementation method:

[0043] This embodiment optimizes the detection device based on the first embodiment so that it can also detect the surface flatness of the electrostatic chuck, while the rest of the parts remain the same as the first embodiment.

[0044] like Figure 12 、 Figure 13As shown, a clearance groove is provided on the side wall of the lower end of the smoothing seat 501, and a flatness scanning component 8 is fixedly connected to the clearance groove. The flatness scanning component 8 includes a fixed seat 801, and a plurality of guide grooves with openings facing downward and distributed at equal intervals are provided on the fixed seat 801. A plane sensing head 802 perpendicular to the passive adsorption membrane 3 is slidably connected in each guide groove. An anti-wear pad 8021 is fixedly connected to the bottom of the plane sensing head 802, and the anti-wear pad 8021 is made of a wear-resistant and smooth material. In order to avoid the friction resistance between the two when the plane sensing head 802 slides on the frictionless scanning layer 303, which causes the plane sensing head 802 to vibrate up and down and affect the detection accuracy, an anti-wear pad is added to the bottom of the plane sensing head 802. 8021, the anti-wear pad 8021 and the frictionless scanning layer 303 are all made of smooth materials, which can greatly reduce the friction resistance, thereby effectively preventing the plane sensing head 802 from vibrating up and down, and thus effectively reducing the flatness detection error, and the upper end of the plane sensing head 802 is fixedly connected to the fixing plate 803, and the middle part of each fixing plate 803 is provided with a perforation, and the centers of the perforations on all the fixing plates 803 are on the same straight line, the flatness scanning component 8 also includes a distributed sensing optical fiber 2 804 (which is a prior art, and the specific structural composition and working principle are well-known technologies for technicians in the relevant field, and will not be described in detail here), and the distributed sensing optical fiber 2 804 passes through the perforation, and the upper end of each fixing plate 803 is aligned with the upper end of the give way groove. Elastic pads 805 are fixedly connected between the inner walls of the ends, and the distributed sensing optical fiber 2 804 is connected to the electromagnet 602 signal through the master control processor (the specific structure and control principle of the electrical connection in this part are well-known technologies for technicians in the relevant field and will not be described in detail here). Since the electrostatic suction cup 1 is affected by thermal expansion and contraction for a long time during operation, its surface will be unevenly deformed. When the driving motor 4 drives the adsorption force scanning component 5 to rotate and scan, the flatness scanning component 8 scans and detects the upper surface of the electrostatic suction cup 1. The flatness sensing head 802 is pressed on the passive adsorption film 3 under the action of gravity and the elastic force of the elastic pad 805. Multiple flatness sensing heads 802 rotate and scan on the passive adsorption film 3. If If the upper surface of the electrostatic chuck 1 is flat, the distributed sensing optical fiber 2 804 will remain in a straight line. If the upper surface of the electrostatic chuck 1 is uneven, the flat sensing head 802 will move up and down when scanning the deformed area, causing the distributed sensing optical fiber 2 804 to bend. After the distributed sensing optical fiber 2 804 is bent and deformed, it sends a signal to the master control processor, which activates all the electromagnets 602. The electromagnets 602 then press the magnetic top block 603 on the mechanochromic film 7, causing the mechanochromic film 7 to display a color-changing line. The inspector marks this line with a marker, indicating that the area covered by this line has been deformed, which can effectively help the inspector locate the location where the electrostatic chuck 1 has been deformed.

[0045] In addition, it should be noted that the flatness scanning assembly 8 is suitable for detecting the flatness of the upper surface of the electrostatic chuck 1 when deformation occurs at the millimeter and centimeter levels. However, detecting deformation of the electrostatic chuck 1 at the micrometer level requires the use of equipment with high-precision detection technology.

[0046] This embodiment not only detects the surface flatness of the electrostatic chuck 1 through the flatness scanning component 8 during scanning, but also detects and locates the electrostatic chuck 1 in a timely manner when it undergoes significant deformation due to heat, thereby effectively preventing the electrostatic chuck 1 from affecting the processing accuracy of the wafer. Compared with the prior art, the flatness detection device of this embodiment has a simple structure, is easy to maintain and operate, and realizes multi-faceted detection of the electrostatic chuck 1.

[0047] In view of current actual needs, the protection scope of the above-mentioned implementation mode adopted in this application is not limited to this. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the protection scope of the present invention.

Claims

1. A device for detecting the uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer, comprising an electrostatic chuck (1) and a transparent detection cover (2) covering the electrostatic chuck (1), characterized in that: The transparent detection cover (2) is provided with a detection cavity with an opening facing downward, and the inner wall of the detection cavity is fixedly connected to a passive adsorption film (3) that is in contact with the electrostatic suction cup (1), a driving motor (4) is installed in the middle of the upper end of the transparent detection cover (2), and a driving shaft connected to the output end of the driving motor (4) is installed inside the detection cavity, the bottom end of the driving shaft is fixedly connected to an adsorption force scanning component (5) that is in contact with the passive adsorption film (3), and the driving shaft is fixedly connected to a positioning member (6) at the upper end of the adsorption force scanning component (5), and the inner wall of the upper end of the detection cavity is fixedly connected to a force-induced chromic film (7) that is in contact with the upper end of the transparent detection cover (2); The adsorption force scanning component (5) includes a smoothing seat (501), an electromagnetic absorption plate (502) fixedly connected to one side of the smoothing seat (501) in the forward direction, and a distributed sensing optical fiber (503) placed directly below the electromagnetic absorption plate (502). The smoothing seat (501) is provided with a groove on the side wall close to the electromagnetic absorption plate (502). Both ends of the distributed sensing optical fiber (503) are fixedly connected to support arms (504) extending into the interior of the groove, and the two support arms (504) are simultaneously rotatably connected to the inner wall of the groove. The upper ends of the two support arms (504) are fixedly connected to a follower. A rotating column (505), the inner wall of the groove is fixedly connected to a rotation angle detection seat (506) which is concentric with the rotation center of the support arm (504), and the outer surface of the rotation angle detection seat (506) is fixedly inlaid with a conductive sheet, and a wire perpendicular to the conductive sheet is fixedly inlaid on the rotating column (505), and the conductive sheet and the wire together form a conductive circuit, and a current detection device connected to the conductive circuit is installed inside the smoothing seat (501), and a master control processor connected to the distributed sensing optical fiber (503) is also installed on the smoothing seat (501), and the master control processor is connected to the positioning member (6) by signal. The passive adsorption film (3) comprises an electrostatic adsorption layer (301) adhered to the electrostatic chuck (1), a frictionless scanning layer (303) adhered to the adsorption force scanning component (5), and a magnetic retraction layer (302) located between the electrostatic adsorption layer (301) and the frictionless scanning layer (303); the electromagnetic retraction plate (502) generates an attraction force on the magnetic retraction layer (302) after being energized, and the maximum magnetic attraction force of the electromagnetic retraction plate (502) on the magnetic retraction layer (302) is less than the electrostatic adsorption force of the electrostatic chuck (1) when it is in operation.

2. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 1, wherein: The magnetic absorption layer (302) is made of a flexible magnetic material, and the frictionless scanning layer (303) is made of a flexible and smooth material.

3. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 1, wherein: The positioning member (6) includes a follower seat (601), and a plurality of equally spaced sliding grooves are provided on the upper side wall of the follower seat (601), and an electromagnet (602) connected to a master control processor signal is installed at the bottom of the sliding groove, a magnetic top block (603) is slidably connected inside the sliding groove, and the electromagnet (602) generates a repulsive force on the magnetic top block (603) when energized, and a plurality of symmetrically distributed elastic bands (604) are fixedly connected between the bottom of the magnetic top block (603) and the electromagnet (602).

4. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 1, wherein: The outside of the distributed sensing optical fiber 1 (503) is wrapped with an anti-wear sleeve (5031), and the anti-wear sleeve (5031) is made of a flexible and smooth material.

5. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 1, wherein: The upper ends of the two support arms (504) are both straight sections, and the straight sections of the support arms (504) abut against the inner wall of the upper end of the groove.

6. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 1, wherein: An alarm is also installed on the transparent detection cover (2), and the alarm is connected to the current detection device signal.

7. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 3, wherein: The lower side wall of the smoothing seat (501) is provided with a clearance groove, and a flatness scanning component (8) is fixedly connected in the clearance groove. The flatness scanning component (8) includes a fixed seat (801), and the fixed seat (801) is provided with a plurality of guide grooves with openings facing downward and distributed at equal intervals. A plane sensing head (802) perpendicular to the passive adsorption film (3) is slidably connected in each of the guide grooves, and a fixing plate (803) is fixedly connected to the upper end of the plane sensing head (802). Each of the fixed The fixed plate (803) is provided with a perforation in the middle, and the centers of the perforations on all the fixed plates (803) are on the same straight line. The flatness scanning component (8) also includes a distributed sensing optical fiber 2 (804), and the distributed sensing optical fiber 2 (804) passes through the perforation. An elastic pad (805) is fixedly connected between the upper end of each fixed plate (803) and the inner wall of the upper end of the yield groove. The distributed sensing optical fiber 2 (804) is connected to the electromagnet (602) signal through the master control processor.

8. The device for detecting uniformity of adsorption force of an electrostatic chuck for a semiconductor wafer according to claim 7, wherein: An anti-wear pad (8021) is fixedly connected to the bottom of the planar sensing head (802), and the anti-wear pad (8021) is made of a wear-resistant and smooth material.

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