Electrostatic chucking device and semiconductor inspection apparatus

Abstract

The application belongs to the technical field of semiconductor manufacturing, and particularly relates to an electrostatic clamping device and a semiconductor detection equipment. The electrostatic clamping device comprises a support table and a plurality of contact electrodes; the plurality of contact electrodes are arranged at intervals on the support table, each contact electrode comprises at least one blade edge; at least part of the blade edge is arranged to protrude from the support table, so as to clamp the circumferential edge of a wafer and pierce the medium layer on the wafer surface. Since the medium layer at the circumferential edge of the wafer is thinner or even does not exist, the blade edge can easily scratch the medium layer at the circumferential edge of the wafer, the piercing probability is greatly improved, and the reliability is better. The blade edges of the contact electrodes are arranged at intervals in the circumferential direction of the wafer, and the wafer is limited in the horizontal direction, so that the risk of wafer slip is reduced.

Description

Technical Field

[0001] This application belongs to the field of semiconductor manufacturing technology, and in particular relates to an electrostatic clamping device and a semiconductor testing equipment. Background Technology

[0002] A charged particle beam device is a device that generates a two-dimensional image of a wafer substrate by detecting secondary electrons, backscattered electrons, mirror electrons, or other types of electrons on the surface of the substrate when struck by a charged particle beam generated by the device. When this device performs its function, the wafer needs to be securely held by an electrostatic or mechanical chuck to prevent displacement during stage movement. Furthermore, charge accumulation in the detected area of ​​the wafer during the detection process can cause image overexposure, drift, and reduced measurement accuracy. Therefore, the wafer typically needs to be in a conductive state to conduct excess charge or to increase voltage bias to protect the wafer.

[0003] There are generally two ways to damage the dielectric layer on a wafer surface: one is to mechanically puncture the dielectric layer on the back of the wafer, and the other is to break down the dielectric layer through pulsed high-voltage discharge. It should be noted that a protective dielectric layer, such as photoresist, is formed on the back surface of the wafer. Existing mechanical puncture structures puncture the protective dielectric layer on the back surface of the wafer using contact pins; however, this puncture method has low reliability. Summary of the Invention

[0004] This application provides an electrostatic clamping device and a semiconductor testing equipment to solve the technical problem that existing mechanical puncture methods are unreliable.

[0005] According to one aspect of this application, an electrostatic clamping device is provided, the electrostatic clamping device including a support platform and a plurality of contact electrodes; the plurality of contact electrodes are spaced apart on the support platform, each contact electrode including at least one cutting edge; at least a portion of the cutting edge protrudes from the support platform for clamping the circumferential edge of a wafer and piercing the dielectric layer on the wafer surface.

[0006] In an optional embodiment of this application, the wafer and the support stage are spaced apart in the thickness direction of the wafer.

[0007] In an optional embodiment of this application, the gap between the wafer and the support stage is 0.05 mm to 0.3 mm.

[0008] In an optional embodiment of this application, the electrostatic clamping device further includes a support column; the support column is connected to the support platform and at least partially protrudes from the surface of the support platform near the wafer; the protrusion height of the support column on the support platform is lower than the protrusion height of the cutting edge on the support platform.

[0009] In an optional embodiment of this application, the cutting edges of the multiple contact electrodes are arranged symmetrically about the center of the support column.

[0010] In an optional embodiment of this application, the distance between the cutting edge and the centerline of the contact electrode is gradually reduced from bottom to top in the thickness direction of the wafer.

[0011] In an optional embodiment of this application, the acute angle between the cutting edge and the axis of the contact electrode is 15° to 75°.

[0012] In the optional embodiment of this application, the end of the contact electrode closest to the wafer is the contact end, and the other end is the lead end; the contact end has a regular polyhedral structure and the multiple edges on the periphery are corresponding to the cutting edges.

[0013] In an optional embodiment of this application, the electrostatic clamping device further includes a protection circuit, which includes a main circuit and multiple parallel branches; one end of each of the multiple parallel branches is connected to the lead end of a multiple contact electrode, and the other end converges into the main circuit; each parallel branch is equipped with a puncture detection module, and the main circuit is equipped with a control switch for connecting to a power source or grounding; the puncture detection module is used to switch the control switch on and off.

[0014] According to another aspect of this application, a semiconductor inspection apparatus is provided, the semiconductor inspection apparatus including a scanning electron microscope and the above-mentioned electrostatic clamping device; the scanning electron microscope is capable of emitting an electron beam to irradiate a wafer placed on the electrostatic clamping device.

[0015] In summary, the electrostatic clamping device and semiconductor testing equipment provided in this application have at least the following beneficial effects:

[0016] In this electrostatic clamping device, multiple contact electrodes on a support platform collectively define a wafer placement area. After the wafer is placed in this area, its circumferential edge abuts against the cutting edges of each contact electrode. Because the dielectric layer at the wafer's circumferential edge is thinner, or even nonexistent, the cutting edges can easily cut through it, greatly increasing the probability of puncture and improving reliability. The cutting edges of the contact electrodes are spaced apart circumferentially on the wafer and provide horizontal restraint, reducing the risk of wafer slippage. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application; those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0018] Figure 1This is a schematic diagram of an electrostatic clamping device for holding a wafer according to one embodiment of this application;

[0019] Figure 2 Showed Figure 1 A schematic diagram of the electrostatic clamping device from another perspective;

[0020] Figure 3 Showed Figure 1 A schematic diagram of the contact electrode;

[0021] Figure 4 for Figure 3 A schematic diagram of the contact electrode from another downward perspective;

[0022] Figure 5 This is a semiconductor testing device provided according to one embodiment of the present application.

[0023] The attached figures are labeled as follows:

[0024] 100. Electrostatic clamping device;

[0025] 110. Support platform;

[0026] 120. Contact electrode; 121. Cutting edge;

[0027] 130. Support column;

[0028] 140. Protection circuit; 141. Main circuit; 142. Parallel branch circuit; 143. Puncture detection module; 144. Control switch;

[0029] 200, wafer; 201, dielectric layer;

[0030] 300. Scanning electron microscope; 301. Electron gun; 302. Optical path system. Detailed Implementation

[0031] In the description of this application, it should be understood that the use of terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" to indicate orientation or positional relationship, unless otherwise specified, is understood to be based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0032] Furthermore, features specified with "first" or "second" for descriptive purposes only should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features specified with "first" or "second" may explicitly or implicitly include at least one of the specified features. The description of "multiple" generally means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this application, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can be a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0034] In the description of this specification, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0035] Those skilled in the art will understand that during the fabrication of wafer 200, wafer 200 is typically coated with a protective dielectric layer 201, such as a photoresist layer or an anti-oxidation layer, to prevent contamination or damage to wafer 200. During electron beam inspection, in order to protect wafer 200, it is necessary to puncture the dielectric layer 201 to bring wafer 200 into a conductive state.

[0036] The inventors discovered that during the manufacturing process of wafer 200, due to the influence of the manufacturing process, it is not easy to form a dielectric layer 201 at the circumferential edge of wafer 200. Therefore, the dielectric layer 201 at the circumferential edge of wafer 200 is thin or even non-existent, which is very advantageous for piercing at the circumferential edge of wafer 200.

[0037] In addition, the inventors also discovered that when it is necessary to perform electron beam testing on the wafer 200, the wafer 200 enters the measurement machine and is adsorbed onto the electrostatic chuck. The electrostatic chuck is provided with multiple contact pins connected to wires. The tips of the multiple contact pins protrude from the electrostatic chuck and are used to pierce the dielectric layer 201 on the surface of the wafer 200.

[0038] However, the contact pin is not located at the circumferential edge of the wafer 200. The piercing depth of the contact pin is relatively large. Due to frequent operation, the contact pin tip is prone to wear, and may even cause the contact pin to fail to completely pierce the dielectric layer 201 on the surface of the wafer 200. It can be seen that the existing piercing method is unreliable.

[0039] In addition, the electrostatic chuck uses electrostatic adsorption to fix the wafer 200. In this fixing method, the wafer 200 is not set with any hard limit. During the high-speed operation of the measurement machine, the wafer 200 is at risk of slippage.

[0040] Based on this, this application provides an electrostatic clamping device 100 to solve at least the above-mentioned problems discovered by the inventors. Figure 1 This is a schematic diagram of an electrostatic clamping device 100 for holding a wafer 200 according to one embodiment of this application. Please refer to... Figure 1 The electrostatic clamping device 100 includes a support platform 110 and a plurality of contact electrodes 120.

[0041] For ease of explanation, in the following embodiments, the surface of the support stage 110 near the wafer 200 is defined as the mesa, the surface of the wafer 200 near the support stage 110 is defined as the back surface, and the surface away from the support stage 110 is defined as the front surface. It should be noted that the mesa of the support stage 110 can be charged with an appropriate charge, using electrostatic force to attract the wafer 200 located above it. The contact electrode 120 is made of conductive metal and connected to wires to put the wafer 200 into a conductive state.

[0042] In this embodiment, a plurality of contact electrodes 120 are spaced apart on the support stage 110, and each contact electrode 120 includes at least one cutting edge 121. At least a portion of the cutting edge 121 protrudes from the support stage 110 to clamp the circumferential edge of the wafer 200 and pierce the dielectric layer 201 on the surface of the wafer 200.

[0043] In this embodiment, multiple contact electrodes 120 are fixedly mounted on the support platform 110 and spaced apart. The multiple contact electrodes 120 together enclose and define the placement area of ​​the wafer 200 on the support platform 110. After the wafer 200 is placed in the placement area, since the cutting edge 121 of each contact electrode 120 protrudes from the platform surface of the support platform 110, the circumferential edge of the wafer 200 can abut against the cutting edge 121 of each contact electrode 120.

[0044] As can be seen from the foregoing, since the dielectric layer 201 at the circumferential edge of the wafer 200 is thinner or even non-existent, when the wafer 200 is placed vertically, under the action of the weight of the wafer 200 and the electrostatic adsorption force on the support platform 110, the cutting edge 121 can easily cut through the dielectric layer 201 at the circumferential edge of the wafer 200, greatly increasing the probability of puncture and improving reliability.

[0045] It should be understood that the cutting edges 121 of each contact electrode 120 are spaced apart along the circumference of the wafer 200 and limit the wafer 200 in the horizontal direction, thereby reducing the risk of wafer 200 slipping during the movement of the measurement equipment.

[0046] In a further optional embodiment, the wafer 200 and the support stage 110 are spaced apart in the thickness direction of the wafer 200.

[0047] It should be noted that in the prior art, the mesa of the support stage 110 has an electrostatic force to attract the wafer 200. The back side of the wafer 200 is in contact with the mesa of the support stage 110, and the contact area between the two is relatively large, which makes it relatively easy to generate particles and affect the product yield.

[0048] In this embodiment, the cutting edge 121 of each contact electrode 120 provides a certain support for the wafer 200, so that a gap is formed between the back side of the wafer 200 and the table surface of the support stage 110, and the back side of the wafer 200 does not contact the table surface of the support stage 110, so as to form non-contact adsorption, reduce the risk of particle generation, and improve the product yield.

[0049] In a further optional embodiment, the gap between the wafer 200 and the support stage 110 is 0.05 mm to 0.3 mm. In this embodiment, by reasonably setting the size of the cutting edge 121 in the contact electrode 120 and the arrangement position of each contact electrode 120, after the wafer 200 is placed in the area defined by each contact electrode 120, each cutting edge 121 defines the support position of the wafer 200, so that the gap between the wafer 200 and the support stage 110 is 0.05 mm to 0.3 mm. This gap distance can ensure that the electrostatic force on the table surface of the support stage 110 can act on the wafer 200.

[0050] It should be understood that if the gap between the wafer 200 and the support stage 110 is too large, the electrostatic force on the surface of the support stage 110 will be insufficient to hold the wafer 200, resulting in reduced stability. Furthermore, the overall size of the electrostatic clamping device 100 will increase, leading to structural redundancy and hindering miniaturization. In a preferred embodiment, the gap between the wafer 200 and the support stage 110 is 0.1 mm to 0.15 mm.

[0051] In some alternative embodiments, the electrostatic clamping device 100 further includes a support post 130 connected to the support platform 110 and at least partially protruding from the surface of the support platform 110 near the wafer 200. In other words, at least a portion of the support post 130 protrudes from the platform surface of the support platform 110.

[0052] The protrusion height of the support column 130 on the support platform 110 is lower than the protrusion height of the cutting edge 121 on the support platform 110. In this embodiment, the protrusion height of the support column 130 on the support platform 110 refers to the distance the support column 130 extends relative to the surface of the support platform 110. Correspondingly, the protrusion height of the cutting edge 121 on the support platform 110 refers to the distance the cutting edge 121 extends relative to the surface of the support platform 110.

[0053] In this embodiment, the support post 130 is used to support the wafer 200 and, together with the cutting edges 121 of the multiple contact electrodes 120, forms a multi-point support to ensure support reliability. Furthermore, since the cutting edges 121 and the support post 130 have different protrusion heights relative to the support stage 110, when the wafer 200 is placed vertically, the wafer 200 first contacts the cutting edge 121 and then the support post 130, thus ensuring that the cutting edge 121 will always contact the circumferential edge of the wafer 200.

[0054] Furthermore, the gap between the wafer 200 and the support stage 110 is controlled by setting the protrusion height of the support post 130. In specific applications, the protrusion height of the support post 130 on the support stage 110 is lower than the protrusion height of the contact electrode 120 on the support stage 110, thereby ensuring that it is lower than the protrusion height of the cutting edge 121 on the support stage 110.

[0055] Figure 2 Showed Figure 1 A schematic diagram of the electrostatic clamping device 100 from another perspective. Please refer to... Figure 2 In a further optional embodiment, the cutting edges 121 of the plurality of contact electrodes 120 are arranged symmetrically about the center of the support post 130.

[0056] In this embodiment, the support post 130 is located at the center of the area enclosed by the multiple contact electrodes 120. That is, after the wafer 200 is placed in this area, the support post 130 provides support to the center of the wafer 200, which can effectively limit the deformation of the wafer 200 and reduce the risk of the wafer 200 breaking under the action of electrostatic adsorption force and gravity.

[0057] When there is only one support pillar 130, it is preferably placed at the center of the wafer 200 to reduce the risk of breakage. Of course, there can also be multiple support pillars 130, and in the case of multiple support pillars, the installation position of the support pillars 130 is not limited to this.

[0058] In practical applications, when the multiple contact electrodes 120 have an axisymmetric structure, the multiple cutting edges 121 are arranged symmetrically about the support pillar 130 by arranging the multiple contact electrodes 120 symmetrically with respect to the support pillar 130. Furthermore, in the illustrated embodiment, the number of contact electrodes 120 is three, but it is not limited to this; ensuring that the number of contact electrodes 120 is not less than three is sufficient to ensure stable clamping of the wafer 200.

[0059] Figure 3 Showed Figure 1 A schematic diagram of the middle contact electrode 120. Figure 4 for Figure 3 A schematic diagram of the contact electrode 120 from another downward perspective. In some alternative embodiments, the spacing between the cutting edge 121 and the axis of the contact electrode 120 is gradually reduced from bottom to top in the thickness direction of the wafer 200.

[0060] It should be noted that, in this embodiment, the contact electrode 120 includes a main body and a contact end. The main body is a rotating structure, and the axis of the contact electrode 120 is the axis of the main body. The contact end is spliced ​​to the main body along the axial direction of the main body, and the cutting edge 121 is located at the contact end.

[0061] As can be seen, in this embodiment, for any contact electrode 120, the cutting edge 121 is inclined relative to the axis of the contact electrode 120. For any cutting edge 121 that contacts the wafer 200, the higher the position, the closer it is to the axis of the contact electrode 120 corresponding to that cutting edge 121, and correspondingly, the farther away it is from the center of the wafer 200. In this way, the area enclosed by each cutting edge 121 in each contact electrode 120 that contacts the wafer 200 is gradually narrowed from top to bottom in the thickness direction of the wafer 200, thus forming a funnel-shaped structure.

[0062] This allows the wafer 200 to self-center, ensuring that it remains as horizontal as possible each time it is placed, thus guaranteeing repeatability and positioning accuracy.

[0063] As described above, in one optional embodiment, the electrostatic clamping device 100 further includes a support post 130, which is located at the center of the area defined by the plurality of contact electrodes 120. When the wafer 200 is placed in this area, due to the funnel-shaped structure of the area, under the action of gravity and the electrostatic attraction force of the support platform 110, the wafer 200 moves slightly relative to the cutting edge 121 toward the support platform 110 and then abuts against the support post 130. At this time, the cutting edge 121 can cut through the dielectric layer 201 at the circumferential edge of the wafer 200 and define the gap between the wafer 200 and the support platform 110.

[0064] It should be understood that if the acute angle between the cutting edge 121 and the axis of the contact electrode 120 is too small, the supporting force of the cutting edge 121 on the wafer 200 will be small. During the placement of the wafer 200, the micro-movement speed of the wafer 200 will be relatively large, resulting in a relatively large impact with the support post 130. If the acute angle between the cutting edge 121 and the axis of the contact electrode 120 is too large, the supporting force of the cutting edge 121 on the wafer will be too large. During the placement of the wafer 200, the micro-movement distance of the wafer 200 will be too small, or it may not even be able to contact the support post 130.

[0065] Therefore, in this embodiment, the acute angle between the cutting edge 121 and the axis of the contact electrode 120 should be appropriate, specifically 15° to 75°. Preferably, the acute angle between the cutting edge 121 and the axis of the contact electrode 120 is 20° to 45°.

[0066] In one optional embodiment, the end of the contact electrode 120 closest to the wafer 200 is the contact end, and the other end is the lead end. The contact end has a regular polygonal pyramidal structure, and the multiple edges on its periphery correspond to the cutting edges 121.

[0067] In this embodiment, the contact end is a regular polygonal pyramid, and the multiple edges on the periphery of the contact end correspond to the cutting edges 121. The multiple cutting edges 121 can be switched to extend the service life of the contact electrode 120.

[0068] In the illustrated embodiment, the contact end is a triangular pyramid structure. Of course, the contact end is not limited to a regular triangular pyramid structure. For example, it can also be a regular square pyramid, a regular pentagonal pyramid, or a regular polyhedron structure, or a regular triangular frustum, a regular square frustum, or a regular polyhedron structure. These will not be listed here.

[0069] In specific applications, the contact electrode 120 is made of a conductive ultra-hard material to ensure its conductivity and service life, and the resistance of the contact electrode 120 is no greater than 10 ohms.

[0070] In an optional embodiment, the electrostatic clamping device 100 further includes a protection circuit 140, which includes a main circuit 141 and multiple parallel branches 142. One end of each parallel branch 142 is connected to a lead end of a plurality of contact electrodes 120, and the other ends converge at the main circuit 141. Each parallel branch 142 is equipped with a puncture detection module 143, and the main circuit 141 is equipped with a control switch 144 for connecting to a power source or grounding. The puncture detection module 143 is used to switch the control switch 144 on and off.

[0071] In this embodiment, after the cutting edge 121 in the contact electrode 120 cuts through the dielectric layer 201 on the surface of the wafer 200, the protection circuit 140 is electrically connected to the wafer 200 through the contact electrode 120.

[0072] The number of parallel branches 142 in the protection circuit 140 is equal to the number of contact electrodes 120 and they are connected one by one. The puncture detection module 143 is set on any of the parallel branches 142. After the contact electrode 120 punctures the dielectric layer 201 on the surface of the wafer 200, the control switch 144 is in the connected state, and the main circuit 141 is in the conducting state, that is, the entire protection circuit 140 is in the conductive state, thereby grounding the wafer 200 or applying a bias voltage to the wafer 200.

[0073] The puncture detection module 143 is used to monitor and detect puncture events on the dielectric layer 201 of the wafer 200. The puncture detection module 143 generally consists of a sensor and a detection circuit. The sensor is used to detect whether the contact electrode 120 and the wafer 200 are in a conductive state, for example, by detecting the resistance of the wafer 200 to verify whether a puncture has occurred. The puncture detection circuit is used to amplify and filter the signal generated by the sensor to ensure accurate detection of puncture events.

[0074] In practical applications, the control switch 144 uses a relay to achieve the action associated with the puncture detection module 143, but it is not limited to this.

[0075] As can be seen from the above embodiments, when the wafer 200 is transferred above the electrostatic clamping device 100 and then slowly placed on the electrostatic clamping device 100, the peripheral edge of the wafer 200 first contacts the cutting edge 121 of the contact electrode 120 to ensure that the dielectric layer 201 can be cut. In addition, the cutting edges 121 of the multiple contact electrodes 120 clamp and fix the wafer 200, which can effectively prevent the risk of wafer 200 slipping when the measuring instrument moves at high speed.

[0076] In addition, the support column 130 at the center of the electrostatic clamping device 100 supports the center of the wafer 200 to limit the deformation of the wafer 200 and prevent the wafer 200 from breaking under the action of electrostatic field and gravity. It also forms multi-point support so that the wafer 200 and the support stage 110 are arranged with gaps to reduce the contact area and reduce the risk of particles caused by contact.

[0077] Moreover, the contact ends of the multiple contact electrodes 120 adopt a regular pyramidal structure and are arranged symmetrically about the center of the support column 130, which is more conducive to the self-centering of the wafer 200 and ensures the horizontal placement and repeatability accuracy of the wafer 200.

[0078] Figure 5 This is a semiconductor testing apparatus according to one embodiment of this application. Please refer to... Figure 5Another aspect of this application provides a semiconductor inspection apparatus, which includes a scanning electron microscope 300 and the aforementioned electrostatic clamping device 100. The scanning electron microscope 300 is capable of emitting an electron beam to irradiate a wafer 200 placed on the electrostatic clamping device 100.

[0079] In this embodiment, the scanning electron microscope 300 includes an electron gun 301 and an optical path system 302. The electron gun 301 can emit an electron beam, which is focused, accelerated, and deflected by the optical path system 302 and then irradiates the wafer 200 placed on the electrostatic clamping device 100.

[0080] As can be seen from the foregoing, after the wafer 200 is placed on the electrostatic clamping device 100, the dielectric layer 201 of the wafer 200 is scratched, and the protection circuit 140 is electrically connected to the wafer 200 through the contact electrode 120.

[0081] In one alternative embodiment, the main circuit 141 is grounded, thereby eliminating accumulated charge on the surface of wafer 200. In another alternative embodiment, the main circuit 141 is connected to a power supply, thereby applying a bias voltage to wafer 200 to slow down the electron beam in the event of excessively high energy, preventing the high-energy electron beam from directly bombarding wafer 200 and causing damage.

[0082] Of course, the semiconductor testing equipment also has other advantages brought about by the electrostatic clamping device 100, which will not be repeated here.

[0083] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An electrostatic clamping device, characterized in that, The electrostatic clamping device includes a support platform, a support column, and multiple contact electrodes; Multiple contact electrodes are spaced apart on the support platform, and each contact electrode includes at least one cutting edge; The support post is connected to the support platform and at least partially protrudes from the surface of the support platform near the wafer, and the protrusion height of the support post on the support platform is lower than the protrusion height of the cutting edge on the support platform. The wafer and the support platform are spaced apart in the thickness direction of the wafer, and the cutting edges of the plurality of contact electrodes are symmetrically arranged about the center of the support column; At least a portion of the cutting edge protrudes from the support platform to clamp the circumferential edge of the wafer and pierce the dielectric layer on the surface at the circumferential edge of the wafer.

2. The electrostatic clamping device according to claim 1, characterized in that, The gap between the wafer and the support stage is 0.05 mm to 0.3 mm.

3. The electrostatic clamping device according to claim 1, characterized in that, The distance between the cutting edge and the centerline of the contact electrode is gradually reduced from bottom to top in the thickness direction of the wafer.

4. The electrostatic clamping device according to claim 3, characterized in that, The acute angle between the cutting edge and the axis of the contact electrode is 15° to 75°.

5. The electrostatic clamping device according to any one of claims 1 to 3, characterized in that, The contact electrode has a contact end at one end near the wafer and a lead end at the other end. The contact end has a regular polyhedral pyramid structure and the multiple edges on its periphery correspond to the cutting edges.

6. The electrostatic clamping device according to claim 5, characterized in that, The electrostatic clamping device also includes a protection circuit, which includes a main circuit and multiple parallel branches. One end of each of the multiple parallel branches is connected to the lead end of each of the multiple contact electrodes, and the other end converges into the main branch. Each of the parallel branches is equipped with a puncture detection module, and the main branch is equipped with a control switch for connecting to a power source or grounding; The puncture detection module is used to switch the control switch on and off.

7. A semiconductor testing device, characterized in that, Includes a scanning electron microscope and an electrostatic clamping device according to any one of claims 1 to 6; The scanning electron microscope is capable of emitting an electron beam to irradiate the wafer placed on the electrostatic clamping device.

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