Wafer static elimination device

Abstract

The utility model provides a wafer static elimination device which comprises a piezoelectric sensitive element, a voltage control module and a charge detection module, the voltage control module is used for controlling voltage applied to the piezoelectric sensitive element, and the charge detection module is used for detecting static charges on a target wafer. After the electrostatic charges on the target wafer are eliminated, the voltage control module is controlled to cut off the voltage applied to the piezoelectric sensitive element, the piezoelectric sensitive element generates elastic deformation according to the voltage applied to the piezoelectric sensitive element, and the elastic deformation process generated by the piezoelectric sensitive element is relatively uniform; the piezoelectric sensitive element is in contact with the target wafer after generating elastic deformation so as to eliminate static electricity on the target wafer, and meanwhile, the piezoelectric sensitive element does not impact the surface of the wafer when being in contact with the target wafer due to the fact that the piezoelectric sensitive element is uniform in the process of generating elastic deformation, so that the static electricity on the target wafer is eliminated. Therefore, the piezoelectric sensitive element is prevented from damaging the surface of the wafer.

Description

Technical Field

[0001] This application belongs to the field of semiconductor technology, and more particularly, relates to a wafer static electricity elimination device. Background Art

[0002] Semiconductor critical dimension measurement equipment is a metrology system based on a scanning electron microscope and is used to view and measure the critical dimensions of chips. They ensure the accuracy and quality of chip manufacturing. To ensure the normal operation of the electron optical system, the cavity used for testing in this type of equipment needs to be maintained in a high vacuum environment. The vacuum degree in the cavity generally needs to be maintained at 10 -5 -10 -7 Torr. When in use, an electron beam is excited by an electron gun and emitted into the cavity and onto a sample fixed on a vacuum chuck, and information about the appearance and morphology of the substance is obtained by collecting the secondary electron beam excited by the sample.

[0003] Due to the high vacuum characteristics of this type of cavity, after measuring the sample, there are static charges remaining on the surface of the wafer. Currently, generally, a contact probe in contact with the back of the wafer is used to guide the static charges on the wafer to avoid problems such as the influence of the static charges on the wafer on the reliability of the measurement and the abnormal yield rate of the wafer.

[0004] Adopting the above technical solution, the problems that occur are: in the existing measurement equipment, the probe is arranged below the vacuum chuck, and the probe is driven by a driving motor to abut against the back of the wafer to conduct the static charges on the wafer. Since the stroke of the probe in the vacuum chuck is relatively short, during the process of the driving motor driving the probe to contact the wafer, the movement process of the probe is unstable, the probe is likely to impact and damage the back of the wafer, and the fragments after the wafer is broken will fall onto the wafer below, affecting the lower layer of the wafer. Summary of the Invention

[0005] The purpose of the embodiments of this application is to provide a wafer static electricity elimination device capable of moving at a uniform speed to solve the technical problem that the existing measurement equipment is prone to damaging the wafer during wafer measurement.

[0006] To achieve the above purpose, the technical solution adopted in this application is: providing a wafer static electricity elimination device, including:

[0007] A piezoelectric sensitive element, which generates elastic deformation according to the voltage applied thereto and contacts the target wafer when generating elastic deformation to eliminate the static charges on the target wafer;

[0008] A voltage control module, electrically connected to the piezoelectric sensitive element, for controlling the voltage applied to the piezoelectric sensitive element;

[0009] A charge detection module, electrically connected to the voltage control module, is configured to detect static charges on the target wafer and control the voltage control module to disconnect the voltage applied to the piezoelectric sensitive element after the static electricity on the target wafer is eliminated.

[0010] With the above technical solution, the piezoelectric sensitive element has an inverse voltage effect, that is, when a voltage is applied to the piezoelectric sensitive element, the piezoelectric sensitive element generates mechanical deformation, and when the voltage applied to the piezoelectric sensitive element is withdrawn, the piezoresistive element returns to its shape before deformation. The piezoelectric sensitive element is made of piezoelectric ceramics or quartz. By utilizing the inverse voltage effect of the piezoelectric sensitive element, the voltage applied to the piezoelectric sensitive element is adjusted through the voltage control module, so that the piezoelectric sensitive element generates elastic deformation.

[0011] When the charge detection module detects static charges on the target wafer, the charge detection module issues a first control instruction and transmits the first control instruction to the voltage control module. The voltage control module applies a voltage to the piezoelectric sensitive element according to the first control instruction. The piezoelectric sensitive element generates elastic deformation according to the voltage applied thereto, so that the piezoelectric sensitive element is in direct or indirect contact with the target wafer, and conducts the static charges on the target wafer to eliminate the static charges on the target wafer until the static charges on the target wafer are eliminated.

[0012] When the charge detection module detects that the static charges on the target wafer have been eliminated, the charge detection module issues a second control instruction and transmits the second control instruction to the voltage control module. The voltage control module disconnects the voltage applied to the piezoelectric sensitive element according to the second control instruction. The piezoelectric sensitive element returns to its initial shape according to the inverse voltage effect, so that the piezoelectric sensitive element is separated from the target wafer.

[0013] After a voltage is applied to the piezoelectric sensitive element, the elastic deformation process of the piezoelectric sensitive element is relatively uniform. After the deformed piezoelectric sensitive element is in direct or indirect contact with the target wafer, it will not cause an impact on the target wafer, thereby preventing the piezoelectric sensitive element from damaging the target wafer, and further improving the yield rate of the target wafer.

[0014] Optionally, one end of the piezoelectric sensitive element facing the target wafer is an arc-shaped curved surface structure;

[0015] When the piezoelectric sensitive element generates elastic deformation, the curved surface structure abuts against the target wafer.

[0016] With the above technical solution, when the piezoelectric sensitive element is in direct contact with the target wafer, by setting the end of the piezoelectric sensitive element facing the target wafer into an arc-shaped curved surface structure, the surface of the target wafer can be further prevented from being damaged by the piezoelectric sensitive element.

[0017] Optionally, a conductive coating is provided on the outer side of the piezoelectric sensitive element, and the charge detection module is electrically connected to the conductive coating.

[0018] With the above technical solution, when the electrically sensitive element is in direct contact with the target wafer, in order to improve the conduction efficiency of the piezoelectric sensitive element for the static charges on the target wafer, a conductive coating is coated on the outer side of the piezoelectric sensitive element, so that the static charges can be conducted through the conductive coating on the outer side of the piezoelectric sensitive element, thereby improving the detection accuracy of the voltage control module for the static charges on the target wafer.

[0019] Optionally, it further includes:

[0020] An electrostatic chuck, provided with a mounting groove, the piezoelectric sensitive element is mounted in the mounting groove, and after the piezoelectric sensitive element generates elastic deformation, it extends outside the mounting groove and abuts against the target wafer.

[0021] With the above technical solution, the electrostatic chuck is used to fix the target wafer. At the same time, by providing the mounting groove on the electrostatic chuck, it is convenient to mount the piezoelectric sensitive element, and along the axis of the electrostatic chuck, the length dimension of the piezoelectric sensitive element is smaller than the length dimension of the mounting groove. After the piezoelectric sensitive element is mounted in the mounting groove, when the voltage control module applies a voltage to the piezoelectric sensitive element, the piezoelectric sensitive element generates elastic deformation and extends outside the mounting groove to abut against the target wafer.

[0022] Optionally, the number of the mounting grooves is multiple, and the multiple mounting grooves are evenly spaced along the circumferential direction of the electrostatic chuck, and the voltage control module is mounted in each mounting groove.

[0023] With the above technical solution, by providing a plurality of the mounting grooves in the circumferential direction of the electrostatic chuck, and mounting the piezoelectric sensitive element in each mounting groove, after the piezoelectric sensitive element generates elastic deformation according to the voltage applied thereto, the plurality of piezoelectric sensitive elements abut against the target wafer to ensure the reliability of the static charge elimination of the wafer static elimination device for the target wafer.

[0024] Optionally, it further includes:

[0025] An electrostatic adsorption plate, used for adsorbing and fixing the target wafer, wherein the electrostatic adsorption plate is provided with a through hole, and the through hole penetrates the electrostatic adsorption plate;

[0026] A bracket connected to the piezoelectric sensitive element, wherein the piezoelectric sensitive element drives the bracket to move after generating elastic deformation;

[0027] A contact pin is connected to the bracket and slidably connected in the through hole, and the contact pin is electrically connected to the charge detection module. The contact pin is used to abut against the target wafer under the drive of the bracket to eliminate static electricity on the target wafer.

[0028] By adopting the above technical scheme, the piezoelectric sensitive element generates elastic deformation when the voltage is turned on, and the elastic deformation process of the piezoelectric sensitive element is relatively uniform. The deformation of the piezoelectric sensitive element along the axial direction of the through hole causes the bracket to move toward the target wafer, and the locking bracket drives the contact pin to slide in the through hole toward the target wafer at a uniform speed, so that the contact pin abuts against the target wafer, which prevents the contact pin from causing damage to the surface of the target wafer and enables the contact pin to eliminate the electrostatic charge on the target wafer.

[0029] Optionally, there are multiple contact pins, and the multiple contact pins are arranged at intervals along the length direction of the bracket.

[0030] By adopting the above technical solution, a plurality of the contact pins are arranged on the bracket, and at least one of the plurality of contact pins can abut against the target wafer under the drive of the piezoelectric sensitive element and the bracket, the wafer static elimination device can adapt to the target wafers with different degrees of curvature.

[0031] Optionally, a guide rod is provided on the bracket, and the axial direction of the guide rod is parallel to the axial direction of the through hole.

[0032] By adopting the above technical solution, a guide hole can be set on the side of the electrostatic adsorption disk away from the target wafer, the guide hole is parallel to the through hole, and the guide rod is slidably connected in the guide hole. When the piezoelectric sensitive element drives the bracket to move toward the target wafer, the guide rod slides in the guide hole, thereby ensuring the movement direction of the bracket.

[0033] Optionally, there are multiple brackets, and the multiple brackets are arranged at angles to each other.

[0034] With the above technical solution, by arranging the plurality of the brackets at an angle to each other, the plurality of the touch pins are evenly distributed in the circumferential direction of the electrostatic adsorption disk, so as to provide a plurality of conductive contacts in the circumferential direction of the electrostatic adsorption disk. This can not only enable the wafer electrostatic elimination device to adapt to target wafers of different size specifications, but also enable the wafer electrostatic elimination device to adapt to target wafers of different bending degrees.

[0035] Optionally, an elastic member is provided between the touch pin and the bracket.

[0036] With the above technical solution, by arranging the elastic member between the touch pin and the bracket, when the bracket drives the touch pin to abut against the target wafer, the elastic member is used to buffer the touch pin to further prevent the touch pin from damaging the surface of the target wafer.

[0037] The beneficial effect of the wafer electrostatic elimination device provided by the present application is that: compared with the prior art, the wafer electrostatic elimination device provided by the present application includes a piezoelectric sensitive element, a voltage control module, and a charge detection module. Among them, the voltage control module is used to control the voltage applied to the piezoelectric sensitive element, and the charge detection module is used to detect the static charges on the target wafer and control the voltage control module to disconnect the voltage applied to the piezoelectric sensitive element after the static charges on the target wafer are eliminated. The piezoelectric sensitive element generates elastic deformation according to the voltage applied thereto, and the process of elastic deformation generated by the piezoelectric sensitive element is relatively uniform. After generating elastic deformation, the piezoelectric sensitive element contacts the target wafer to eliminate the static electricity on the target wafer. At the same time, because the process of elastic deformation generated by the piezoelectric sensitive element is relatively uniform, when the piezoelectric sensitive element contacts the target wafer, it will not impact the surface of the wafer, thereby preventing the piezoelectric sensitive element from damaging the surface of the wafer. Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0039] Figure 1 It is a schematic structural diagram of the wafer electrostatic elimination device provided by the embodiment of the present application;

[0040] Figure 2 It is a cross-sectional view of the piezoelectric sensitive element provided by the embodiment of the present application;

[0041] Figure 3 It is a schematic structural diagram when the piezoelectric sensitive element provided by the embodiment of the present application is separated from the target wafer;

[0042] Figure 4 Schematic diagram of the structure when the piezoelectric sensitive element provided by the embodiment of the present application abuts against the target wafer;

[0043] Figure 5 Schematic diagram of the structure of the electrostatic chuck provided by the embodiment of the present application;

[0044] Figure 6 Schematic diagram of the structure of the wafer electrostatic elimination device provided by another embodiment of the present application;

[0045] Figure 7 Schematic diagram of the structure when the stylus separates from the target wafer provided by the embodiment of the present application;

[0046] Figure 8 Schematic diagram of the structure when the stylus abuts against the target wafer provided by the embodiment of the present application;

[0047] Figure 9 Schematic diagram of the structure of the bracket provided by the embodiment of the present application;

[0048] Figure 10 Schematic diagram of the structure of the bracket provided by another embodiment of the present application;

[0049] Figure 11 Schematic diagram of the structure of the bracket provided by another embodiment of the present application.

[0050] Among them, the reference numerals in the figure are as follows:

[0051] 10. Piezoelectric sensitive element; 11. Curved surface structure; 20. Voltage control module; 30. Charge detection module; 40. Target wafer; 50. Conductive coating; 60. Electrostatic chuck; 61. Mounting groove; 62. Accommodating hole; 63. Through hole; 64. Guide hole; 70. Bracket; 71. Guide rod; 80. Stylus; 90. Elastic member. Detailed implementation manners

[0052] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0053] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0054] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0055] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0056] Please refer to Figures 1 to 11 for an illustration of the wafer electrostatic elimination device provided by the embodiments of the present application.

[0057] A wafer electrostatic elimination device includes a piezoelectric sensitive element 10, a voltage control module 20, and a charge detection module 30.

[0058] Please refer to Figure 1 and Figure 2 . The piezoelectric sensitive element 10 is made of a material with an inverse voltage effect, that is, when a voltage is applied to the piezoelectric sensitive element 10, the piezoelectric sensitive element 10 will generate mechanical deformation in its polarization direction, and when the voltage applied to the piezoelectric sensitive element 10 is removed, the piezoelectric sensitive element 10 will return to its initial shape, thereby causing the piezoelectric sensitive element 10 to generate elastic deformation. In the present application, the piezoelectric sensitive element 10 can be made of piezoelectric ceramics or quartz materials. For the convenience of description, in the present application, it is taken as an example that the piezoelectric sensitive element 10 is made of piezoelectric ceramic material. Among them, the piezoelectric ceramic is made of any one of PZT (lead zirconate titanate ceramic), BaTiO3 (barium titanate ceramic), AlN (aluminum nitride ceramic), and ZnO (zinc oxide ceramic).

[0059] The voltage control module 20 is electrically connected to the piezoelectric sensitive element 10 and is used to control the voltage applied to the piezoelectric sensitive element 10, so that the piezoelectric sensitive element 10 generates elastic deformation according to the voltage applied to it and directly or indirectly contacts the target wafer 40 when generating elastic deformation to eliminate the static charges on the target wafer 40.

[0060] The charge detection module 30 is electrically connected to the voltage control module 20, and is configured to detect the static electricity charge on the target wafer 40, and control the voltage control module 20 to disconnect the voltage applied to the piezoelectric sensing element 10 after the static electricity on the target wafer 40 is eliminated.

[0061] With the above technical solution, the piezoelectric sensing element 10 has an inverse voltage effect, that is, when a voltage is applied to the piezoelectric sensing element 10, the piezoelectric sensing element 10 generates mechanical deformation, and when the voltage applied to the piezoelectric sensing element 10 is withdrawn, the piezoresistive element returns to the shape before deformation. The piezoelectric sensing element 10 is made of piezoelectric ceramics or quartz materials. By utilizing the inverse voltage effect of the piezoelectric sensing element 10, the voltage applied to the piezoelectric sensing element 10 is adjusted through the voltage control module 20, so that the piezoelectric sensing element 10 generates elastic deformation.

[0062] When the charge detection module 30 detects that there is static electricity charge on the target wafer 40, the charge detection module 30 issues a first control instruction and transmits the first control instruction to the voltage control module 20. The voltage control module 20 applies a voltage to the piezoelectric sensing element 10 according to the first control instruction. The piezoelectric sensing element 10 generates elastic deformation according to the voltage applied thereto, so that the piezoelectric sensing element 10 directly or indirectly contacts the target wafer 40, and conducts the static electricity charge on the target wafer 40 to eliminate the static electricity charge on the target wafer 40 until the static electricity charge on the target wafer 40 is eliminated.

[0063] When the charge detection module 30 detects that the static electricity charge on the target wafer 40 is eliminated, the charge detection module 30 issues a second control instruction and transmits the second control instruction to the voltage control module 20. The voltage control module 20 disconnects the voltage applied to the piezoelectric sensing element 10 according to the second control instruction. The piezoelectric sensing element 10 returns to its initial shape according to the inverse voltage effect, so that the piezoelectric sensing element 10 is separated from the target wafer 40.

[0064] Compared with the prior art, in the wafer static electricity elimination device provided in the present application, when a voltage is applied to the piezoelectric sensing element 10, the elastic deformation process of the piezoelectric sensing element 10 is relatively uniform. After deformation, when the piezoelectric sensing element 10 directly or indirectly contacts the target wafer 40, it will not cause an impact on the target wafer 40, thereby preventing the piezoelectric sensing element 10 from damaging the target wafer 40, and further improving the yield rate of the target wafer 40.

[0065] In an embodiment of the present application, after the piezoelectric sensing element 10 generates elastic deformation, it directly contacts the target wafer 40. The following takes the direct contact between the piezoelectric sensing element 10 and the target wafer 40 to eliminate the static electricity charge on the target wafer 40 as an example for illustration.

[0066] In this embodiment, referring to FIG. 1, one end of the piezoelectric sensing element 10 facing the target wafer 40 is an arc-shaped curved surface structure 11. The curved surface structure 11 is formed by rotating a preset curve around the central axis of the piezoelectric sensing element 10 for one week. Among them, the central angle corresponding to both ends of the preset curve is less than or equal to 90°. The piezoelectric sensing element 10 undergoes elastic deformation, and the curved surface structure 11 abuts against the target wafer 40.

[0067] In another embodiment of the present application, one end of the piezoelectric sensing element 10 facing the target wafer 40 is a planar structure.

[0068] Compared with the prior art technical solution of eliminating the static charges on the target wafer 40 through the stylus 80, by setting one end of the piezoelectric sensing element 10 facing the target wafer 40 as an arc-shaped curved surface structure 11 or a planar structure, when the piezoelectric sensing element 10 is in direct contact with the target wafer 40, the contact area between the piezoelectric sensing element 10 and the target wafer 40 is increased, and the pressure exerted on the target wafer 40 when the piezoelectric sensing element 10 abuts against the target wafer 40 is reduced, thereby preventing the piezoelectric sensing element 10 from damaging the surface of the target wafer 40.

[0069] In the present application, referring to Figure 2 , a conductive coating 50 is provided on the outer side of the piezoelectric sensing element 10 to improve the conduction efficiency of the static charges on the target wafer 40 by the piezoelectric sensing element 10.

[0070] When the electro-sensitive element is in direct contact with the target wafer 40, a conductive coating 50 is coated on the outer side of the piezoelectric sensing element, so that the static charges on the target wafer 40 can be conducted through the conductive coating 50. The conductive coating 50 can be made of metal materials, such as metal gold, silver, copper, etc. Of course, the conductive coating 50 can also be made of metal oxides, such as tin oxide, indium oxide, cadmium oxide, etc. For the convenience of description, in the present application, the conductive coating 50 is taken as an example of metal copper for description.

[0071] The charge detection module 30 is electrically connected to the conductive coating 50 on the outer side of the piezoelectric sensing element 10. The static charges on the target wafer 40 can be conducted through the conductive coating 50 to the charge detection module 30 to improve the detection accuracy of the voltage control module 20 for the static charges on the target wafer 40.

[0072] In the present application, referring to Figure 3 and Figure 4 , the wafer static charge elimination device further includes an electrostatic adsorption disk 60. The electrostatic adsorption disk 60 is provided with a vacuum adsorption port, and the vacuum adsorption port is externally connected to a vacuum generator to adsorb the target wafer 40 on the electrostatic adsorption disk 60. The electrostatic adsorption disk 60 is provided with a mounting groove 61, and the piezoelectric sensing element is installed in the mounting groove 61.

[0073] Among them, the electrostatic adsorption disk 60 is a circular disk-shaped structure. The shape of the installation groove 61 is arc-shaped, and the extending direction of the installation groove 61 is consistent with the circumferential direction of the electrostatic adsorption disk 60. The shape of the piezoelectric sensitive element 10 is also an arc-shaped structure. The piezoelectric sensitive element 10 is installed in the installation groove, and along the axial direction of the electrostatic adsorption disk 60, the length dimension of the piezoelectric sensitive element 10 before elastic deformation is smaller than the length dimension of the installation groove 61, that is, there is a gap between the side of the piezoelectric sensitive element 10 facing the target wafer 40 and the opening of the installation groove 61 facing the target wafer 40. After the piezoelectric sensitive element 10 generates elastic deformation according to the voltage applied thereto, the side of the piezoelectric sensitive element 10 facing the target wafer 40 extends to the outside of the installation groove 61 to abut against the target wafer 40, so as to eliminate the static charges on the target wafer 40.

[0074] A receiving hole 62 is provided at the bottom of the installation groove 61. The voltage control module 20 and the charge detection module 30 are electrically connected to the piezoelectric sensitive element 10 through wires, and the wires penetrate through the receiving hole 62.

[0075] In another embodiment of the present application, the installation groove 61 is a circular hole structure, the shape of the piezoelectric sensitive element 10 is a circular columnar structure, the piezoelectric sensitive element 10 is installed in the installation groove 61, and along the axial direction of the electrostatic adsorption disk 60, the length dimension of the piezoelectric sensitive element 10 before elastic deformation is smaller than the length dimension of the installation groove 61.

[0076] In the present application, please refer to Figure 5 , the number of the installation grooves 61 is multiple. The multiple installation grooves 61 are evenly spaced along the circumferential direction of the electrostatic adsorption disk 60, and a piezoelectric sensitive element 10 is installed in each installation groove 61.

[0077] Among them, the number of the voltage control module 20 and the charge detection module 30 is both one, and the voltage control module 20 and the charge detection module 30 are electrically connected to the multiple piezoelectric sensitive elements 10 through wires at the same time, that is, the multiple piezoelectric sensitive elements 10 are simultaneously controlled by the same piezoelectric control module and the same charge detection module 30.

[0078] Preferably, in the present application, the number of the installation grooves 61 is 4. Correspondingly, the number of the piezoelectric sensitive elements 10 is also 4. The 4 piezoelectric sensitive elements 10 correspond to the 4 installation grooves 61 one by one, and each piezoelectric sensitive element 10 is installed in the corresponding installation groove 61.

[0079] In another embodiment of the present application, please refer to again Figure 6, the number of the voltage control modules 20 and the charge detection modules 30 is the same as that of the piezoelectric sensitive elements 10. Each voltage control module 20 is electrically connected to the corresponding piezoelectric sensitive element 10, and each charge detection module 30 is electrically connected to the corresponding piezoelectric sensitive element 10 and the voltage control module 20. Each piezoelectric sensitive element 10 is independently controlled by the corresponding voltage control module 20 and charge detection module 30.

[0080] With the above technical solution, by providing a plurality of mounting grooves 61 in the circumferential direction of the electrostatic adsorption disk 60, and installing a piezoelectric sensitive element 10 in each mounting groove 61, after the piezoelectric sensitive element 10 generates elastic deformation according to the voltage applied thereto, the plurality of piezoelectric sensitive elements 10 are abutted against the target wafer 40, so that at least one piezoelectric sensitive element 10 in the wafer electrostatic elimination device is abutted against the target wafer 40, thereby ensuring the reliability of the wafer electrostatic elimination device for eliminating the static charges on the target wafer 40.

[0081] In an embodiment of the present application, after the piezoelectric sensitive element 10 generates elastic deformation, it is indirectly in contact with the target wafer 40. The following takes the indirect contact between the piezoelectric sensitive element 10 and the target wafer 40 to eliminate the static charges on the target wafer 40 as an example for description.

[0082] In the present application, please refer to Figures 7 to 9 , the wafer electrostatic elimination device further includes an electrostatic adsorption disk 60, a bracket 70 and a touch pin 80.

[0083] Specifically, the electrostatic adsorption disk 60 is a circular disk-shaped structure. The electrostatic adsorption disk 60 is provided with a vacuum adsorption port, and the vacuum adsorption port is externally connected to a vacuum generator to adsorb and fix the target wafer 40 on the electrostatic adsorption disk 60. The electrostatic adsorption disk 60 is provided with a through hole 63, and the through hole 63 penetrates through the electrostatic adsorption disk 60.

[0084] The bracket 70 is a rod-shaped structure, or the bracket 70 is a plate-shaped structure. For the convenience of description, in the present application, the bracket 70 is taken as an example of a rod-shaped structure for description.

[0085] The middle part of the bracket 70 is connected to the piezoelectric sensitive element 10. The piezoelectric sensitive element 10 generates elastic deformation along the axial direction of the through hole 63 to drive the bracket 70 to move along the axial direction of the through hole 63. The touch pin 80 is connected to the bracket 70 and is slidably connected in the through hole 63, and the touch pin 80 is electrically connected to the charge detection module 30. When the bracket 70 moves along the axial direction of the through hole 63 under the drive of the piezoelectric sensitive element 10, the touch pin 80 slides in the through hole 63 under the drive of the bracket 70 to abut against the target wafer 40, so as to realize the indirect abutment between the piezoelectric sensitive element 10 and the target wafer 40, thereby eliminating the static charges on the target wafer 40.

[0086] With the above technical solution, when the piezoelectric sensitive element 10 is powered on, it generates elastic deformation, and the elastic deformation process of the piezoelectric sensitive element 10 is relatively uniform. The deformation of the piezoelectric sensitive element 10 in the axial direction of the through hole 63 drives the bracket 70 to move towards the target wafer 40. The bracket 70 drives the stylus 80 to slide uniformly towards the target wafer 40 in the through hole 63, so that the stylus 80 abuts against the target wafer 40. While preventing the stylus 80 from impacting the surface of the target wafer 40 and causing damage to the surface of the target wafer 40, it can also enable the stylus 80 to eliminate the static charges on the target wafer 40, and the charges on the target wafer 40 are conducted through the stylus 80 to eliminate the static charges on the target wafer 40.

[0087] In one embodiment of the present application, an elastic member 90 is provided between the stylus 80 and the bracket 70. One end of the elastic member 90 is connected to the bracket 70, and the other end of the elastic member 90 is connected to the stylus 80.

[0088] Specifically, the elastic member 90 is a spring, and an annular baffle is convexly provided on the outer wall of the stylus 80. One end of the spring close to the stylus 80 abuts against the baffle.

[0089] In another embodiment of the present application, the elastic member 90 is a gasket supported by perfluororubber or silica gel.

[0090] With the above technical solution, by providing the elastic member 90 between the stylus 80 and the bracket 70, when the bracket 70 drives the stylus 80 to abut against the target wafer 40, the elastic member 90 is used to buffer the stylus 80 to further prevent the stylus 80 from damaging the surface of the target wafer 40.

[0091] In the present application, please refer to Figure 10 , the number of the styli 80 is multiple, and the multiple styli 80 are arranged at intervals along the length direction of the bracket 70.

[0092] With the above technical solution, by providing multiple styli 80 on the bracket 70, and among the multiple styli 80, at least one stylus 80 can abut against the target wafer 40 under the drive of the piezoelectric sensitive element 10 and the bracket 70, and the wafer static elimination device can adapt to target wafers 40 with different bending degrees.

[0093] In the present application, a guide rod 71 is provided on the bracket 70. The axial direction of the guide rod 71 is parallel to the axial direction of the through hole 63, and the guide rod 71 is symmetrically arranged on the bracket 70 with respect to the piezoelectric sensitive element 10.

[0094] With the above technical solution, a guiding hole 64 can be arranged on the side of the electrostatic adsorption disk 60 facing away from the target wafer 40. The guiding hole 64 is parallel and spaced from the through hole 63. The guiding rod 71 is slidably connected in the guiding hole 64. When the piezoelectric sensitive element 10 drives the bracket 70 to move towards the target wafer 40, the guiding rod 71 slides in the guiding hole 64, so as to ensure the moving direction of the bracket 70.

[0095] In an embodiment of the present application, the number of brackets 70 is multiple. One ends of the multiple brackets 70 close to the piezoelectric sensitive element 10 are integrally arranged, and the multiple brackets 70 are arranged at an angle to each other.

[0096] Please refer to Figure 10 , preferably, the number of brackets 70 is 4. Among the 4 brackets 70, the included angle between any two adjacent brackets 70 is 90°.

[0097] Please refer to Figure 11 , in another embodiment of the present application, the number of brackets 70 is 6, and the included angle between any two adjacent brackets 70 is 60°.

[0098] With the above technical solution, by arranging the multiple brackets 70 at an angle to each other, so that the multiple contact pins 80 are evenly distributed in the circumferential direction of the electrostatic adsorption disk 60, it can not only make the wafer electrostatic elimination device adapt to target wafers 40 of different size specifications, but also make the wafer electrostatic elimination device adapt to target wafers 40 with different bending degrees.

[0099] Compared with the prior art, the wafer electrostatic elimination device provided by the present application includes a piezoelectric sensitive element 10, a voltage control module 20 and a charge detection module. Among them, the voltage control module 20 is used to control the voltage applied to the piezoelectric sensitive element 10, and the charge detection module is used to detect the static charges on the target wafer 40 and control the voltage control module 20 to disconnect the voltage applied to the piezoelectric sensitive element 10 after the static charges on the target wafer 40 are eliminated. The piezoelectric sensitive element 10 generates elastic deformation according to the voltage applied thereto, and the elastic deformation process generated by the piezoelectric sensitive element 10 is relatively uniform. After generating elastic deformation, the piezoelectric sensitive element 10 contacts the target wafer 40 to eliminate the static electricity on the target wafer 40. At the same time, because the elastic deformation process of the piezoelectric sensitive element 10 is relatively uniform, when the piezoelectric sensitive element 10 contacts the target wafer 40, it will not impact the surface of the wafer, thereby preventing the piezoelectric sensitive element 10 from damaging the surface of the wafer.

[0100] The above are only the preferred embodiments of the present application, and are not used to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A wafer static elimination device, characterized in that: include: a piezoelectric sensitive element, wherein the piezoelectric sensitive element generates elastic deformation according to a voltage applied thereto, and contacts a target wafer after the elastic deformation to eliminate static electricity on the target wafer; A voltage control module, electrically connected to the piezoelectric sensitive element, and used to control the voltage applied to the piezoelectric sensitive element; The charge detection module is electrically connected to the voltage control module, and is used to detect the electrostatic charge on the target wafer, and control the voltage control module to disconnect the voltage applied to the piezoelectric sensitive element after the electrostatic charge on the target wafer is eliminated.

2. The wafer static elimination device according to claim 1, characterized in that: One end of the piezoelectric sensitive element facing the target wafer is an arc-shaped curved surface structure; The piezoelectric sensitive element generates elastic deformation, and the curved surface structure abuts against the target wafer.

3. The wafer static elimination device according to claim 2, characterized in that: A conductive coating is disposed on the outer side of the piezoelectric sensitive element, and the charge detection module is electrically connected to the conductive coating.

4. The wafer static elimination device according to claim 1 or 3, characterized in that: Also includes: The electrostatic adsorption plate is provided with a mounting groove, the piezoelectric sensitive element is mounted in the mounting groove, and the piezoelectric sensitive element extends out of the mounting groove and abuts against the target wafer after elastic deformation.

5. The wafer static elimination device according to claim 4, characterized in that: There are a plurality of mounting grooves, and the plurality of mounting grooves are evenly spaced along the circumference of the electrostatic adsorption plate, and the piezoelectric sensitive element is installed in each of the mounting grooves.

6. The wafer static elimination device according to claim 1, characterized in that: Also includes: An electrostatic adsorption plate, used for adsorbing and fixing the target wafer, wherein the electrostatic adsorption plate is provided with a through hole, and the through hole penetrates the electrostatic adsorption plate; A bracket connected to the piezoelectric sensitive element, wherein the piezoelectric sensitive element drives the bracket to move after generating elastic deformation; A contact pin is connected to the bracket and slidably connected in the through hole. The contact pin is electrically connected to the charge detection module. The contact pin is used to abut against the target wafer under the drive of the bracket to eliminate the electrostatic charge on the target wafer.

7. The wafer static elimination device according to claim 6, characterized in that: There are a plurality of contact pins, and the plurality of contact pins are arranged at intervals along the length direction of the bracket.

8. The wafer static elimination device according to claim 7, characterized in that: The bracket is provided with a guide rod, and the axial direction of the guide rod is parallel to the axial direction of the through hole.

9. The wafer static elimination device according to claim 8, characterized in that: There are multiple brackets, and the multiple brackets are arranged at angles to each other.

10. The wafer static elimination device according to claim 9, characterized in that: The contact pin and the bracket are provided with elastic members.

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