An electrostatic chuck electrostatic adsorption force measuring device

Abstract

The present invention discloses an electrostatic adsorption force measuring device for an electrostatic chuck, which belongs to the technical field of electrostatic chucks. The device comprises a vacuum chamber and a vacuum acquisition device connected to the vacuum chamber, wherein the vacuum chamber is arranged on a frame, and an electrostatic chuck and an adsorbent side-pulling device are arranged in the vacuum chamber, wherein the adsorbent side-pulling device comprises a positioning device and a driving component, wherein the positioning device is connected to the driving component through a flexible cable, wherein the adsorbent side-pulling device further comprises a limiting component for keeping the flexible cable parallel, wherein the limiting component is arranged between the driving component and the positioning device, wherein a tension sensor is arranged between the limiting component and the positioning device, and wherein the tension sensor is arranged on the flexible cable.

Description

Technical Field

[0001] The invention relates to the technical field of electrostatic chucks, and in particular to a device for measuring the electrostatic adsorption force of an electrostatic chuck. Background Art

[0002] In the process of integrated circuit (IC) manufacturing, electrostatic chuck equipment is widely used. The electrostatic chuck uses the principle of electrostatic adsorption to adsorb the wafer to be processed on its surface, and can control the temperature of the wafer surface by back-blowing gas. It is usually placed at the bottom of the vacuum process chamber, generally including a base and a dielectric layer on the base. The wafer is placed on a dielectric layer made of ceramic with good thermal conductivity. A DC power supply is connected to the electrode buried in the dielectric layer. Polarized charges will be generated on the surface of the dielectric layer, and then opposite polarized charges will be induced at the corresponding position on the surface of the wafer. Through the Coulomb force or JR force formed between the dielectric layer and the wafer, the wafer is firmly adsorbed and fixed on the electrostatic chuck.

[0003] The electrostatic adsorption force of the electrostatic chuck is an important performance indicator of the electrostatic chuck. If the electrostatic force is too small, it cannot balance the back-blowing gas pressure and cannot fix the wafer. If the electrostatic force is too large, it will not only prolong the desorption time and reduce production efficiency, but also affect the helium back-blowing filling the gap between the wafer and the electrostatic chuck, indirectly affecting the temperature control effect of the wafer. The process has very strict requirements on the wafer temperature. The temperature and its uniformity are directly related to the final processing quality and yield rate of the product. Therefore, it is very necessary to accurately measure the electrostatic force of the electrostatic chuck, the wafer desorption time and the wafer temperature distribution.

[0004] Existing detection devices generally measure electrostatic force by vertically pulling the wafer upward. However, due to the large area of ​​the wafer, the force is often uneven during the pulling process, resulting in local desorption. It is difficult to ensure uniform desorption of the entire wafer, which not only increases the measurement error, but also easily causes the wafer to deform or even break. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an electrostatic adsorption force measuring device for an electrostatic chuck, which can measure the adsorption force of the electrostatic chuck.

[0006] In order to solve the above technical problems, the technical solution of the present invention is:

[0007] A device for measuring the electrostatic adsorption force of an electrostatic chuck, comprising a vacuum chamber and a vacuum acquisition device connected to the vacuum chamber, wherein the vacuum chamber is arranged on a frame, wherein an electrostatic chuck and an adsorbent side-pulling device are arranged in the vacuum chamber, wherein the adsorbent side-pulling device comprises a positioning device and a driving component, wherein the positioning device is connected to the driving component via a flexible cable, wherein the adsorbent side-pulling device further comprises a limiting component for keeping the flexible cable parallel, wherein the limiting component is arranged between the driving component and the positioning device, wherein a tension sensor is arranged between the limiting component and the positioning device, and wherein the tension sensor is arranged on the flexible cable.

[0008] Preferably, the positioning device comprises a positioning ring assembly and a positioning joint assembly, the positioning ring assembly comprises a positioning ring rope, one end of the positioning ring rope is fixedly connected to the positioning joint assembly, and the other end of the positioning ring rope is slidably connected to the positioning joint assembly.

[0009] Preferably, a plurality of anti-sliding blocks are provided on the positioning ring rope, and the length direction of any one of the anti-sliding blocks is arranged along the up-down direction.

[0010] Preferably, the positioning joint assembly comprises a shell, the shell is connected to the frame via a support frame, and a first channel for passing the positioning grommet is provided in the shell.

[0011] Preferably, a grommet limit assembly is provided on one side of the first through hole, and the grommet limit assembly is arranged in the shell. The grommet limit assembly includes a limit block, and the limit block is connected to the inner wall of the shell by a spring. A second channel for the limit block to pass through is provided in the shell, and the second channel is connected to the first channel. A lever is provided on the limit block, and the lever passes through the shell and extends outside the shell. A limit through groove cooperating with the lever is provided on the shell.

[0012] Preferably, the limiting block comprises an inclined side wall, a front side wall facing the first channel and a left side wall facing the positioning device, and the inclined side wall is arranged between the front side wall and the left side wall.

[0013] Preferably, the anti-slip block includes anti-slip strips arranged in the up and down directions.

[0014] Preferably, the limiting assembly comprises a limiting ring, the limiting ring is provided with a limiting hole for allowing the flexible cable to pass through, and the limiting ring is connected to the frame via a support rod.

[0015] Preferably, the tension sensor is arranged between the limiting ring and the shell.

[0016] Preferably, the driving assembly comprises a telescopic rod, a power output end of the telescopic rod is connected to the flexible cable, and an end of the telescopic rod away from the power output end is connected to the frame.

[0017] By adopting the above technical scheme, by setting up a side-pulling device for the adsorbed object, the wafer adsorbed on the suction cup can be pulled from the side, so as to calculate the magnitude of the adsorption force of the electrostatic chuck; by setting up a positioning component and a driving component, the wafer adsorbed on the electrostatic chuck can be connected to the driving component; by setting up a tension sensor, the magnitude of the pulling force can be obtained; by setting up a limit component, it can be ensured that the wafer adsorbed on the electrostatic chuck is pulled in the horizontal direction during work, so as to measure the adsorption force of the electrostatic chuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of an electrostatic adsorption force measuring device of an electrostatic chuck according to the present invention;

[0019] Figure 2 It is an enlarged structural schematic diagram of the side-pulling device for adsorbed objects of the present invention;

[0020] Figure 3 It is a schematic diagram of the enlarged structure of the anti-sliding block of the present invention viewed from above;

[0021] Figure 4 It is an enlarged structural schematic diagram of the housing of the present invention;

[0022] Figure 5 It is a schematic diagram of the enlarged structure of the limit block of the present invention. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] like Figure 1-Figure 5 As shown, Figure 1 This is a schematic structural diagram of a device for measuring electrostatic adsorption force of an electrostatic chuck according to the present invention. Figure 2 It is a structural schematic diagram of the side-pulling device for adsorbed objects of the present invention, Figure 3 It is a schematic diagram of the enlarged structure of the anti-sliding block of the present invention viewed from above. Figure 4 is an enlarged structural schematic diagram of the housing of the present invention, Figure 5It is an enlarged structural schematic diagram of the limit block of the present invention, including a vacuum chamber 2 and a vacuum acquisition device connected to the vacuum chamber 2, the vacuum chamber 2 and the vacuum acquisition device improve the vacuum environment for adsorption force measurement, the vacuum chamber 2 is arranged on the frame 1, and an electrostatic chuck 3 and an adsorbent side pulling device are arranged in the vacuum chamber 2, the electrostatic chuck 3 is used to adsorb a wafer 4, the adsorbent side pulling device is used to pull the wafer 4 adsorbed on the electrostatic chuck 3 from the side, so as to measure the adsorption force of the electrostatic chuck 3, the adsorbent side pulling device includes a positioning device and a driving component, the positioning device is connected to the driving component through a flexible cable 22, and the adsorbent side pulling device also includes a limiting group for keeping the flexible cable 22 parallel The limiting component is arranged between the driving component and the positioning device, a tension sensor 8 is arranged between the limiting component and the positioning device, and the tension sensor 8 is arranged on the flexible cable 22. The positioning component is used to position the wafer 4 on the electrostatic chuck 3 so that the wafer 4 on the electrostatic chuck 3 can be pulled laterally to measure the electrostatic adsorption force of the electrostatic chuck 3. The driving component is used to provide power for pulling the wafer 4 after the positioning component positions the wafer 4 on the electrostatic chuck 3. The positioning device and the driving component are connected through the flexible cable 22. The flexible cable 22 can be a steel cable or a nylon rope. The driving component can drive the positioning device to move, thereby driving the wafer 4 on the electrostatic chuck 3.

[0025] The positioning device includes a positioning ring assembly and a positioning joint assembly 6, the positioning ring assembly includes a positioning ring rope 5, one end of the positioning ring rope 5 is fixedly connected to the positioning joint assembly 6, and the other end of the positioning ring rope 5 is slidably connected to the positioning joint assembly 6. The size of the positioning ring rope 5 can be changed through the sliding connection to adapt to wafers 4 of different sizes. The positioning ring rope 5 can be a nylon rope;

[0026] The positioning ring rope 5 is provided with a plurality of anti-sliding blocks 12, and the length direction of any anti-sliding block 12 is arranged along the up-down direction. When in use, the anti-sliding block 12 is fitted with the outer side wall of the wafer 4 to facilitate positioning of the wafer 4. The anti-sliding block 12 can be made of rubber material;

[0027] The positioning joint assembly 6 includes a shell, which is connected to the frame 1 through a support frame 7. A first channel 15 for passing the positioning grommet is provided in the shell. The first channel 15 is used to allow the positioning grommet 5 to pass through so that the anti-sliding block 12 on the positioning grommet 5 can contact the outer side wall of the wafer 4. The shell can be made of plastic and includes an upper shell and a lower shell, which are spliced ​​into one piece.

[0028] A grommet limiting assembly is provided on one side of the first through hole, and the grommet limiting assembly is arranged in the shell. The grommet limiting assembly includes a limiting block 16, and the limiting block 16 is connected to the inner wall of the shell by a spring 17. A second channel 14 for the limiting block 16 to pass through is provided in the shell, and the second channel 14 is connected to the first channel 15. A lever 21 is provided on the limiting block 16, and the lever 21 passes through the shell and extends out of the shell. A limiting through groove cooperating with the lever 21 is provided on the shell. The grommet limiting assembly is used for the active end of the positioning ring rope 5. After the positioning ring rope 5 completes the positioning with the wafer 4, the active end of the positioning ring rope 5 can be locked by the grommet limiting assembly to ensure the positioning. The stability of the ring rope 5 is ensured. When in use, the positioning ring rope 5 is clamped by the limit block 16, so that the position of the movable end of the positioning ring rope 5 is limited, and the position of the limit block 16 is limited by the second channel 14. At the same time, the limit block 16 is connected to the inner wall of the shell through the spring 17. The elastic force of the spring 17 can make the limit block 16 support the positioning ring rope 5, and then fix the positioning ring rope 5 on the wafer 4. The lever 21 can be moved during adjustment to further compress the spring 17, so that the movable end of the positioning ring rope 5 can be movable. After the positioning ring rope 5 is adjusted, the movable end of the positioning ring rope 5 can be loosened, so that the limit block 16 supports the positioning ring rope 5.

[0029] The limit block 16 includes an inclined side wall 18, a front side wall 20 facing the first channel 15, and a left side wall 19 facing the positioning device. The inclined side wall 18 is arranged between the front side wall 20 and the left side wall 19. By setting the inclined side wall 18, the anti-sliding block 12 can better pass through the limit block 16 when the positioning ring rope 5 is positioned. The front side wall 20 of the limit block 16 is relatively narrow, which can better clamp the positioning ring rope 5.

[0030] The anti-slip block 12 includes an anti-slip strip 13 arranged in the up-down direction, which can better position the wafer 4 and avoid damaging the wafer 4. The anti-slip strip 13 can be made of rubber material and can be processed together with the anti-slip block 12.

[0031] The limiting assembly includes a limiting ring 9, in which a limiting hole for the flexible cable 22 to pass is provided. The limiting ring 9 is connected to the frame 1 through a support rod 10. The limiting ring 9 is used to limit the position of the flexible cable 22 so that the flexible cable 22 can remain horizontal, so as to better and more accurately measure the adsorption force of the electrostatic chuck 3.

[0032] The tension sensor 8 is arranged between the limit ring 9 and the housing. The tension sensor 8 is arranged on the flexible cable 22 between the limit ring 9 and the housing. One end of the flexible cable 22 is connected to the housing, and the other end is connected to the driving component.

[0033] The driving assembly includes a telescopic rod 11, the power output end of the telescopic rod 11 is connected to the flexible cable 22, and one end of the telescopic rod 11 away from the power output end is connected to the frame 1. The telescopic rod 11 can be a hydraulic cylinder with stable power output. The oil pipe of the hydraulic cylinder extends out of the vacuum chamber 2 through the hole of the vacuum chamber 2. A sealing ring can be provided between the oil pipe and the vacuum chamber 2 to ensure the vacuum environment in the vacuum chamber 2. The telescopic rod 11 can be fixedly provided on the side wall of the vacuum chamber 2;

[0034] By setting up a side-pulling device for the adsorbed object, the wafer 4 adsorbed on the suction cup can be pulled from the side, so as to calculate the magnitude of the adsorption force of the electrostatic chuck 3. By setting up a positioning component and a driving component, the wafer 4 adsorbed on the electrostatic chuck 3 can be connected to the driving component. By setting up a tension sensor 8, the magnitude of the pulling force can be obtained. By setting up a limit component, it can be ensured that the wafer 4 adsorbed on the electrostatic chuck 3 is pulled in the horizontal direction during operation, so as to measure the adsorption force of the electrostatic chuck 3.

[0035] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

Claims

1. An electrostatic adsorption force measuring device for an electrostatic chuck, comprising a vacuum chamber and a vacuum acquisition device connected to the vacuum chamber, characterized in that: The vacuum chamber is arranged on a frame, an electrostatic chuck and an adsorbent side-pulling device are arranged in the vacuum chamber, the adsorbent side-pulling device comprises a positioning device and a driving component, the positioning device is connected to the driving component through a flexible cable, the adsorbent side-pulling device further comprises a limiter component for keeping the flexible cable parallel, the limiter component is arranged between the driving component and the positioning device, a tension sensor is arranged between the limiter component and the positioning device, and the tension sensor is arranged on the flexible cable; The positioning device comprises a positioning ring assembly and a positioning joint assembly, the positioning ring assembly comprises a positioning ring rope, one end of the positioning ring rope is fixedly connected to the positioning joint assembly, and the other end of the positioning ring rope is slidably connected to the positioning joint assembly; The positioning joint assembly comprises a shell, the shell is connected to the frame via a support frame, and a first channel for passing the positioning grommet is provided in the shell; The shell is also provided with a grommet limit assembly, which includes a limit block, which is connected to the inner wall of the shell by a spring, and a second channel for the limit block to pass through is provided in the shell, and the second channel is connected to the first channel, and a lever is provided on the limit block, and the lever passes through the shell and extends outside the shell, and a limit groove cooperating with the lever is provided on the shell.

2. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 1, characterized in that: A plurality of anti-sliding blocks are arranged on the positioning ring rope, and the length direction of any one of the anti-sliding blocks is arranged along the up-down direction.

3. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 2, characterized in that: The limiting block comprises an inclined side wall, a front side wall facing the first channel and a left side wall facing the positioning device, and the inclined side wall is arranged between the front side wall and the left side wall.

4. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 3, characterized in that: The anti-slip block includes anti-slip strips arranged in the up and down directions.

5. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 1, characterized in that: The limiting assembly comprises a limiting ring, in which a limiting hole is provided for the flexible cable to pass through, and the limiting ring is connected to the frame via a supporting rod.

6. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 5, characterized in that: The tension sensor is arranged between the limiting ring and the shell.

7. The electrostatic adsorption force measuring device of an electrostatic chuck according to claim 1, characterized in that: The driving assembly comprises a telescopic rod, a power output end of the telescopic rod is connected to the flexible cable, and an end of the telescopic rod away from the power output end is connected to the frame.

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