Wafer detection equipment and method

Abstract

The invention provides wafer detection equipment and method, and relates to the technical field of semiconductor manufacturing. The equipment comprises a base platform, a wafer carrying table movably arranged on the base platform, a front surface detection device arranged above the wafer carrying table, and a back surface detection device arranged below the wafer carrying table. The back face detection device comprises a supporting part for supporting the wafer, a containing cavity is formed in the supporting part, and the containing cavity is filled with transparent liquid to infiltrate the outer surface of a blue film on the back face of the wafer. Light scattering caused by frosted texture of the blue film is eliminated through infiltration of the transparent liquid, meanwhile, the wafer is supported through the supporting part to avoid the sagging problem, front and back synchronous detection without overturning of the wafer is achieved, and the technical problems of blue film imaging obstacle and automatic detection failure in the prior art are solved.

Description

Technical Field

[0001] The present disclosure relates to a wafer detection device, belonging to the technical field of semiconductor manufacturing. Background Art

[0002] Comprehensive inspection of both the front and back sides of wafers is essential in the wafer production and quality inspection process. However, some inspection devices currently on the market have significant limitations, only capable of inspecting either the front or back side of the wafer, failing to meet the need for simultaneous inspection of both sides.

[0003] At the same time, during the wafer processing process, after the cutting process is completed, cutting streets of specific width and depth will be formed on the surface. The micro-texture of these cutting streets presents irregular jagged features, and there is a certain probability that defects such as chipping and hidden cracks will appear on the wafer during the cutting process. Among them, some chipping and hidden cracks will be hidden on the back of the wafer, increasing the difficulty of detection. In addition, the surface of the wafer is embedded with various metal materials. The presence of these metals makes it impossible to simply detect the defects hidden on the back of the wafer directly from the front through a microscope.

[0004] The back of the wafer is typically adhered with a blue film with a frosted outer surface. This frosted texture causes light scattering at the interface, severely hindering microscopic imaging and preventing clear image information from the wafer backside. While light scattering can theoretically be reduced by infiltration with a transparent liquid (for example, by using the principle of refractive index matching to fill the microscopic depressions in the frosted texture), existing inspection equipment relies on wafer flipping, making it difficult to reliably achieve liquid infiltration in an automated process. Consequently, this method has long been unsuitable for practical production. Currently, the industry's common method for detecting defects such as wafer backside cracks and chipping is to flip the wafer 180° and then inspect the backside using a microscope. However, this method presents numerous practical challenges. The flipped wafer surface must not be supported, otherwise it will affect the inspection results. This can lead to sagging in the center of the wafer. High-magnification objective lenses typically have a depth of field of only a few microns. This sagging prevents the image from being focused, significantly impacting the accuracy and stability of inspection. Therefore, this method is currently only suitable for manual inspection scenarios and is difficult to achieve for automated and efficient inspection. Therefore, the existing technology can neither solve the imaging obstacle of the blue film nor cause the failure of automated detection due to the sagging problem. There is an urgent need for a device that does not require flipping and can achieve high-precision detection of both sides at the same time. Summary of the Invention

[0005] The present disclosure provides a wafer inspection device and method.

[0006] According to one aspect of the present disclosure, a wafer inspection device is provided, including: a base platform; a wafer carrier, movably arranged on the base platform, for fixing the wafer; a front detection device, arranged above the wafer carrier, for detecting front defects of the wafer on the wafer carrier; a back detection device, arranged below the wafer carrier, and for detecting back defects of the wafer on the wafer carrier, the back detection device including a supporting portion for supporting the wafer, a cavity for accommodating a transparent liquid being formed in the supporting portion, the transparent liquid being used to infiltrate the outer surface of the blue film on the back of the wafer.

[0007] According to the technical solution of one aspect of the present disclosure, the wafer detection equipment realizes simultaneous detection of the front and back sides of the wafer by setting a front detection device and a back detection device, which solves the limitation of some detection devices in the prior art that can only detect the front or back side of the wafer. At the same time, a cavity is set in the support part of the back detection device, and the transparent liquid filled in the cavity forms a liquid film under the action of surface tension, which infiltrates the outer surface of the blue film on the back of the wafer, reducing the scattering of light at the frosted texture interface, so that the image information of the back side of the wafer can be clearly obtained, overcoming the problem of imaging difficulty caused by the frosted texture of the blue film in the prior art, and there is no need to flip the wafer, and the wafer is supported by the support part of the back detection device, avoiding the problem of wafer sagging affecting the detection accuracy and stability, and meeting the requirements of automated and efficient detection.

[0008] According to the wafer inspection equipment of at least one embodiment of the present disclosure, the back detection device includes: a support head, which is provided with a through hole inside, and the upper end of the hole wall of the through hole forms the support part for carrying the wafer; a transparent plate, made of transparent material, arranged in the through hole, the thickness of the transparent plate is less than the depth of the through hole, and the upper surface of the transparent plate is lower than the upper end surface of the through hole, so that the cavity is formed between the outer surface of the transparent plate and the inner wall surface of the through hole; an optical module, which is arranged below the support head and facing the transparent plate, and is used to obtain the back image of the wafer located on the support part through the transparent plate and the cavity; a moving module, which is provided on the support head and / or the optical module, and is used to drive the support head and the optical module to move relative to each other to adjust the distance between the optical module and the wafer.

[0009] In the technical solution of this embodiment, a through hole is provided inside the support head, and a support portion is formed at the upper end of the through hole wall to support the wafer. A transparent plate is provided in the through hole, and its outer surface and the inner wall of the through hole form a cavity. This structure makes the filling of the cavity and the formation of the liquid film more stable and reliable. The optical module is arranged toward the transparent plate, and can obtain an image of the back of the wafer through the transparent plate and the cavity, thereby ensuring the clarity of the imaging. The movable module can drive the support head and the optical module to move relative to each other, thereby flexibly adjusting the distance between the optical module and the wafer, facilitating the acquisition of clear images at different positions, and improving the flexibility and accuracy of detection.

[0010] According to the wafer inspection equipment of at least one embodiment of the present disclosure, the support head is provided with a liquid injection channel, the liquid injection channel includes a liquid injection interface and a first communicating hole connected in sequence, and the first communicating hole extends to the accommodating cavity; the support head is provided with an annular boss and a water storage tank around the periphery of the through hole, the annular boss constitutes the support part, the water storage tank is located on the outer periphery of the annular boss, and is provided with a water absorption ring made of water-absorbing material; the support head is also provided with a liquid outlet channel, the liquid outlet channel includes a liquid outlet interface and a second communicating hole, one end of the second communicating hole is connected to the water storage tank, and the other end is connected to the liquid outlet interface.

[0011] In the technical solution of this embodiment, the liquid injection channel provided in the support head injects the transparent liquid into the cavity through the liquid injection interface and the first connecting hole, thereby quickly and conveniently filling the cavity with liquid. The annular boss constitutes a support portion that supports the wafer, and the structure is stable. The setting of the water tank and the water absorption ring can absorb the liquid that may overflow during the detection process, thereby preventing the liquid from interfering with the detection. The liquid outlet channel discharges the liquid in the water tank through the liquid outlet interface and the second connecting hole, thereby ensuring the cleanliness and stability of the detection environment, and is conducive to improving the accuracy and reliability of the detection.

[0012] According to at least one embodiment of the wafer detection equipment disclosed in the present invention, the support head is provided with a slot hole on the periphery of the cavity; the back detection device also includes a first liquid return component and a second liquid return component; the first liquid return component is arranged at the lower end of the support head, and is provided with a V-shaped groove and a side hole, the V-shaped groove is opposite to the slot hole, one end of the side hole is connected to the V-shaped groove, and the other end extends to the outside of the first liquid return component, the first liquid return component is provided with a first clearance hole opposite to the through hole; the second liquid return component is arranged at the lower end of the first liquid return component, and is provided with a square groove and a first drainage interface connected to the square groove, the second liquid return component is provided with a second clearance hole opposite to the first clearance hole; wherein, the optical module obtains an image of the wafer carried on the support part through the first clearance hole and the second clearance hole.

[0013] In the technical solution of this embodiment, a slot is provided on the periphery of the cavity of the support head, which is opposite to the V-shaped slot of the first liquid return component, so as to facilitate the flow of liquid from the support head into the first liquid return component. The side hole of the first liquid return component discharges the liquid to the outside, ensuring that the liquid does not accumulate in the first liquid return component. The second liquid return component is provided at the lower end of the first liquid return component, and its square groove and the first liquid discharge interface further collect and discharge the liquid, keeping the entire detection device clean. The provision of the first clearance hole and the second clearance hole enables the optical module to smoothly acquire the wafer image without affecting the detection process, while ensuring the coordination of liquid discharge and image acquisition, thereby improving the overall performance of the detection device.

[0014] According to at least one embodiment of the wafer inspection equipment disclosed herein, a step is provided at the bottom of the square trough, and the step is provided with a second drainage interface. The height of the second drainage interface is higher than the first drainage interface and lower than the top of the square trough, and is connected to an overflow pipe.

[0015] In this embodiment, a step and a second drain port are located at the bottom of the trough. The second port is higher than the first port and lower than the top of the trough, and is connected to an overflow pipe. This design allows the liquid in the trough to automatically drain from either the first or second port depending on the liquid level. When the liquid level is low, it drains from the first port; when the liquid level is high, it drains through the second port and the overflow pipe. This prevents overflow from the trough, ensures stable and reliable liquid drainage, and further maintains the normal operation of the detection device.

[0016] According to the wafer detection equipment of at least one embodiment of the present disclosure, the movable module includes a bracket, a transfer block and a height adjustment shaft connected in sequence, and the bracket is arranged at the lower end of the second liquid return component; the height adjustment shaft is used to drive the transfer block, the bracket, the second liquid return component, the first liquid return component and the support head to move up and down to adjust the distance between the optical module and the wafer; wherein, the bracket is provided with a third clearance hole opposite to the position of the first clearance hole.

[0017] In the technical solution of this embodiment, the mobile module is composed of a bracket, an adapter block, and a height adjustment shaft connected in sequence. The bracket is arranged at the lower end of the second liquid return component. The height adjustment shaft can drive the adapter block, bracket, second liquid return component, first liquid return component, and support head to move up and down, thereby flexibly adjusting the distance between the optical module and the wafer to meet different detection requirements. The third clearance hole set in the bracket is located opposite to the first clearance hole, ensuring that the optical module has a clear channel for acquiring wafer images without affecting the detection process. This allows the mobile module to achieve the height adjustment function while not affecting the image acquisition function of the entire detection device, thereby improving the flexibility and accuracy of detection.

[0018] According to at least one embodiment of the wafer detection equipment of the present disclosure, the wafer detection equipment also includes a first driving mechanism and a first height adjustment mechanism arranged between the base platform and the front detection device, the first driving mechanism and the first height adjustment mechanism are connected to each other, and are respectively used to drive the front detection device to move in a first horizontal direction and a vertical direction; the wafer detection equipment also includes a second driving mechanism and a second height adjustment mechanism arranged between the base platform and the back detection device, the second driving mechanism and the second height adjustment mechanism are connected to each other, and are respectively used to drive the back detection device to move in a first horizontal direction and a vertical direction; the wafer detection equipment also includes a carrier driving mechanism arranged between the base platform and the wafer carrier, the carrier driving mechanism is used to drive the wafer carrier to move along the second horizontal direction; wherein, the first horizontal direction and the second horizontal direction are perpendicular to each other.

[0019] In the technical solution of this embodiment, by providing a first drive mechanism and a first height adjustment mechanism between the base platform and the front detection device, the front detection device can be driven to move in a first horizontal direction and a vertical direction, thereby adjusting the relative position of the front detection device and the wafer in the first direction. A second drive mechanism and a second height adjustment mechanism are provided between the base platform and the back detection device, thereby driving the back detection device to move in a first horizontal direction and a vertical direction, thereby adjusting the relative position of the back detection device and the wafer in the second direction. A carrier drive mechanism is provided between the base platform and the wafer carrier, driving the wafer carrier to move along a second horizontal direction, with the first horizontal direction and the second horizontal direction being perpendicular to each other, thereby adjusting the relative position of the wafer, the front detection device, and the back detection device in the second direction. This multi-directional drive setting enables the wafer detection equipment to flexibly adjust the position of the front detection device and the back detection device relative to the wafer carrier, thereby achieving all-round detection of all areas on the front and back sides of the wafer, thereby improving the comprehensiveness and accuracy of the detection.

[0020] According to the wafer detection equipment of at least one embodiment of the present disclosure, the wafer carrier includes: a base, which is movably arranged on the base platform and connected to the carrier driving mechanism; a carrier body, which is movably arranged above the base and is provided with a positioning ring for positioning the wafer, a material receiving assembly for receiving the positioning ring and a fixing assembly for fixing the positioning ring; a multi-axis guide mechanism arranged on the base, the multi-axis guide mechanism is provided with a guide head, the guide head is connected to the carrier body and has the freedom of movement along the first horizontal direction and the second horizontal direction and the freedom of rotation around the vertical axis; a third driving mechanism and a fourth driving mechanism arranged between the base and the carrier body, which are respectively used to drive the guide head to move along the first horizontal direction and the second horizontal direction.

[0021] In the technical solution of this embodiment, the base of the wafer carrier is connected to the carrier drive mechanism and can be movably arranged on the base platform to achieve overall movement. The carrier body places the wafer on the positioning ring through the material receiving assembly, and carries and fixes the wafer through the positioning ring and the fixing assembly to ensure the stability of the wafer during the loading and testing process. The guide head of the multi-axis guide mechanism is connected to the carrier body and has the freedom to move along the first horizontal direction and the second horizontal direction and the freedom to rotate around the vertical axis. The third drive mechanism and the fourth drive mechanism respectively drive the guide head to move along the first horizontal direction and the second horizontal direction, so that the carrier body can flexibly adjust the position and angle, correct the wafer position, and provide a basis for establishing a wafer detection coordinate system.

[0022] According to one aspect of the present disclosure, a wafer inspection method is provided, which uses a wafer inspection device and includes the following steps: fixing the wafer on a wafer carrier; supporting the wafer by a support portion, and allowing the transparent liquid filled in the cavity to infiltrate the outer surface of the blue film on the back of the wafer; and respectively detecting front defects and back defects of the wafer by a front inspection device and a back inspection device.

[0023] According to the technical solution of one aspect of the present disclosure, the wafer inspection method utilizes the aforementioned wafer inspection equipment. The wafer is first fixed to a wafer stage, supported by a support portion, and the outer surface of the blue film is soaked with a transparent liquid within the cavity, thereby resolving the imaging difficulties caused by the frosted texture of the blue film. The front and back surfaces of the wafer are then inspected for defects using a front inspection device and a back inspection device, respectively. This enables simultaneous inspection of both sides without flipping the wafer. Supporting the wafer with a support portion prevents sagging after flipping, which could affect inspection accuracy and stability. This meets the requirements for automated and efficient inspection, improving inspection efficiency and accuracy.

[0024] According to at least one embodiment of the wafer inspection method disclosed herein, after the wafer is fixed on the wafer carrier, before the front defects and back defects of the wafer are respectively detected by the front detection device and the back detection device, the method further includes the following steps: driving the wafer carrier to move along the second horizontal direction, and driving the front detection device to move along the first horizontal direction, grabbing multiple feature points on the front side of the wafer, calculating the angular deviation value between the wafer cutting path and the detection coordinate system, and correcting the position of the wafer carrier through a multi-axis guiding mechanism to establish a wafer surface coordinate system; driving the back detection device to move along the first horizontal direction to the bottom of the wafer carrier, so that the support head rises to contact and support the outer surface of the blue film; adding transparent liquid into the cavity through the liquid injection channel of the support head, so that the transparent liquid infiltrates the blue film. Outer surface; the detecting of front defects and back defects of the wafer respectively by the front detection device and the back detection device comprises the following steps: controlling the back detection device to move along the scanning path, and collecting a complete image of the back of the wafer through the optical module; driving the front detection device to move along the first horizontal direction to above the wafer carrier, and controlling the front detection device to move along the scanning path to collect a complete image of the front of the wafer, wherein the sagging state of the blue film is monitored in real time during the acquisition process, and when the sagging amount exceeds the depth of field of the objective lens, the support head is driven to move synchronously with the moving trajectory of the front detection device through the moving module to maintain the flatness of the back of the wafer and the surface is within the depth of field of the back detection device; transmitting the front image and the back image of the wafer to the image processing system for defect detection and comparison analysis.

[0025] In the technical solution of this embodiment, before detection, the wafer stage and the front detection device are driven to move, the feature points on the front of the wafer are captured, the angle deviation value is calculated and the position of the wafer stage is corrected, and the wafer surface coordinate system is established, which provides a basis for accurate detection. The back detection device is driven to move so that the support head contacts and supports the outer surface of the blue film, and a transparent liquid is added through the injection channel to form a liquid film to infiltrate the blue film, thereby solving the imaging obstacle. During detection, the back detection device and the front detection device are controlled to move along the scanning path respectively to collect complete images of the front and back of the wafer. During the process of collecting the front image, the sagging state of the blue film is monitored in real time. When the sagging amount exceeds the depth of field of the objective lens, the support head is driven to move synchronously with the front detection device to maintain the back of the wafer flat and within the depth of field of the back detection device, thereby ensuring the quality of image acquisition. Finally, the front and back images are transmitted to the image processing system for defect detection and comparison analysis, thereby realizing accurate detection and analysis of defects on the front and back of the wafer, and improving the accuracy and reliability of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0027] Figure 1 is a perspective view of a back surface detection device according to one embodiment of the present disclosure.

[0028] Figure 2 4 is a front view of a back detection device according to one embodiment of the present disclosure.

[0029] Figure 3 FIG. 4 is an exploded view of a backside detection device according to one embodiment of the present disclosure.

[0030] Figure 4 It is a structural schematic diagram of a back surface detection device according to one embodiment of the present disclosure.

[0031] Figure 5 FIG. 4 is an exploded view of a backside detection device according to one embodiment of the present disclosure.

[0032] Figure 6 yes Figure 4 Schematic diagram of the middle H region.

[0033] Figure 7 1 is an exploded view of a liquid adding module according to one embodiment of the present disclosure.

[0034] Figure 8 is a top view of a support head according to one embodiment of the present disclosure.

[0035] Figure 9 is a cross-sectional perspective view of a support head according to one embodiment of the present disclosure.

[0036] Figure 10 2 is a schematic structural diagram of a first liquid return component according to an embodiment of the present disclosure.

[0037] Figure 11 2 is a schematic structural diagram of a second liquid return component according to an embodiment of the present disclosure.

[0038] Figure 12 FIG. 4 is a top view of a second liquid return component according to one embodiment of the present disclosure.

[0039] Figure 13 is a perspective view of a wafer stage according to one embodiment of the present disclosure.

[0040] Figure 14 is a perspective view of a wafer stage according to one embodiment of the present disclosure.

[0041] Figure 15 is an exploded view of a first drive mechanism according to one embodiment of the present disclosure.

[0042] Figure 16 is a perspective view of a second driving mechanism according to one embodiment of the present disclosure.

[0043] Figure 17 is an exploded view of a first height adjustment mechanism according to one embodiment of the present disclosure.

[0044] Figure 18 is a perspective view of a stage driving mechanism according to one embodiment of the present disclosure.

[0045] The specific reference numerals in the figure are: 100 Backside detection device 110 support head 111 through hole 112 Support 113 cavity 114 Liquid injection port 115 first communication hole 116 annular boss 117 Water Tank 117A water absorption ring 118 liquid outlet port 119 Second communication hole 110A convex ring structure 110B slot 110C Step Groove 120 transparent plate 130 optical modules 131 Microscope 131A objective lens 131B Microscope Mounting Plate 140 Mobile Modules 141 bracket 141A Third yield hole 142 adapter block 143 Height adjustment shaft 150 First liquid return component 151 V-groove 152 side hole 153 First yield hole 154 external threaded shaft 160 Second liquid return component 161 Square Groove 162 First drain port 163 Second yield hole 164 steps 165 Second drain port 166 Overflow pipe 167 Annular mounting groove 168 sealing ring 169 Pipeline interface 170 module base 180 wafers 181 Blue Film 190 transparent liquid 200 front detection device 300 wafer stage 310 base 320 stage body 321 positioning ring 322 splicing components 322A Lifting Mast 323 fixed components 324 Multi-axis guide mechanism 324A Guide Head 325 Third drive mechanism 326 Fourth drive mechanism 400 base platform 500 First drive mechanism 501 marble pad 502 Marble Rail 503 air floating foot cup 504 foot cup mounting plate 505 linear motor 1 506 Limit block 1 600 Second drive mechanism 610 Marble Seat 620 X guide rail 630 Linear Motor 2 640 Mobile Board 2 650 limit block 2 700 stage drive mechanism 710 Y guide rail 720 linear motor three 730 Limit Block 3 800 First height adjustment mechanism 810 ball screw mechanism 820 LM Guide Rail 830 servo motor 840 baseplate 850 side panels 860 Nut Seat 870 motor mounting plate 880 First Mobile Plate 890 Coupling 900 Second height adjustment mechanism DETAILED DESCRIPTION The present disclosure will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the relevant content and are not intended to limit the present disclosure. It should also be noted that, for ease of description, only the portions relevant to the present disclosure are shown in the accompanying drawings.

[0046] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present disclosure can be combined with each other. The technical solution of the present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0047] Unless otherwise stated, the exemplary embodiments / examples shown are to be understood as providing exemplary features of various details of some ways in which the technical concepts of the present disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of the various embodiments / examples may be further combined, separated, interchanged, and / or rearranged without departing from the technical concepts of the present disclosure.

[0048] The use of cross hatching and / or shading in the accompanying drawings is generally used to make the boundaries between adjacent components clear. As such, unless otherwise indicated, the presence or absence of cross hatching or shading does not convey or indicate any preference or requirement for the specific materials, material properties, dimensions, proportions, commonalities between the components shown, and / or any other characteristics, attributes, properties, etc. of the components. In addition, in the accompanying drawings, the sizes and relative sizes of the components may be exaggerated for clarity and / or descriptive purposes. When the exemplary embodiments can be implemented differently, the specific process sequence can be performed in a different order than described. For example, two successively described processes can be performed substantially simultaneously or in an order opposite to the order described. In addition, the same figure numbers represent the same components.

[0049] When a component is referred to as being “on,” “over,” “connected to,” or “coupled to” another component, the component may be directly on, directly connected to, or directly coupled to the other component, or intervening components may be present. However, when a component is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another component, there are no intervening components present. For this purpose, the term “connected” may refer to a physical connection, an electrical connection, etc., with or without intervening components.

[0050] For descriptive purposes, the present disclosure may use spatially relative terms such as "below," "beneath," "under," "down," "above," "upper," "above," "higher," and "side (e.g., as in "sidewall")," to describe the relationship of one component to another (other) component as shown in the accompanying drawings. The spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientation depicted in the accompanying drawings. For example, if the device in the drawings is turned over, a component described as "below" or "beneath" another component or feature would then be positioned "above" the other component or feature. Thus, the exemplary term "below" can encompass both the "above" and "below" orientations. Furthermore, the device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and as such, the spatially relative descriptors used herein should be interpreted accordingly.

[0051] The terms used herein are for the purpose of describing specific embodiments and are not intended to be restrictive. As used herein, unless the context clearly indicates otherwise, the singular forms "one (kind, person)" and "said (the)" are also intended to include plural forms. In addition, when the terms "comprise" and / or "include" and their variations are used in this specification, the features, integral bodies, steps, operations, parts, assemblies and / or their groups stated are explained, but the presence or addition of one or more other features, integral bodies, steps, operations, parts, assemblies and / or their groups is not excluded. It should also be noted that, as used herein, the terms "substantially", "approximately" and other similar terms are used as approximate terms and not as degree terms, so that they are used to explain the inherent deviations of the measured values, calculated values ​​and / or the values ​​provided that will be recognized by those of ordinary skill in the art.

[0052] Some inspection devices currently on the market have limitations and can only inspect the front or back of the wafer, but not both. After wafer cutting, there are cutting lines on the surface, and there are defects such as chipped edges and hidden cracks, some of which are hidden on the back. In addition, the surface of the wafer is made of metal, which increases the difficulty of detecting defects on the back from the front. The frosted texture of the blue film on the back of the wafer causes light scattering, which hinders microscope imaging. Existing equipment relies on wafer flipping, which cannot stably achieve liquid infiltration to reduce scattering and has not been used in actual production. The common method of wafer back inspection in the industry requires a 180° flip. After flipping, the middle of the wafer sags, affecting the imaging focus. It is only suitable for manual inspection and is difficult to achieve automated and efficient inspection. Existing technologies cannot solve the problems of blue film imaging obstacles and automated detection failures. There is an urgent need for equipment that does not require flipping and can achieve high-precision inspection of the front and back sides at the same time.

[0053] In order to solve the above technical problems, this embodiment provides a wafer detection device.

[0054] Figure 1 is a perspective view of a backside detection device according to one embodiment of the present disclosure, Figure 2 is a front view of a back detection device according to one embodiment of the present disclosure, Figure 3 FIG. 4 is an exploded view of a backside detection device according to one embodiment of the present disclosure.

[0055] See Figures 1 to 3 As shown, the wafer inspection equipment of this embodiment includes: a backside inspection device 100 , a frontside inspection device 200 , a wafer stage 300 and a base platform 400 .

[0056] Figure 4 is a schematic structural diagram of a back surface detection device according to one embodiment of the present disclosure. Figure 5 is an exploded view of a backside detection device according to one embodiment of the present disclosure, Figure 6 yes Figure 4 Schematic diagram of the middle H region, Figure 7 1 is an exploded view of a liquid adding module according to one embodiment of the present disclosure.

[0057] See Figures 4 to 7 As shown, the backside inspection device 100 of this embodiment includes: a liquid adding module and an optical module 130 . The liquid adding module includes components such as a support head 110 , a transparent plate 120 and a moving module 140 .

[0058] Figure 8 is a top view of a support head according to one embodiment of the present disclosure.

[0059] See Figure 6 and Figure 8 As shown, the support head 110 is provided with a through hole 111 therein for allowing the light path of the optical module 130 to pass through. The upper end of the through hole 111 forms a support portion 112 for supporting the wafer 180 .

[0060] Transparent plate 120 is made of a transparent material and is disposed within through-hole 111. The thickness of transparent plate 120 is less than the depth of through-hole 111. That is, its upper surface is located within through-hole 111 and lower than the upper end surface of through-hole 111. This forms a cavity 113 between the outer surface of transparent plate 120 and the inner wall of through-hole 111. Cavity 113 is used to contain transparent liquid 190. Transparent plate 120 may be a conventional glass plate.

[0061] like Figure 5 and Figure 6As shown, optical module 130 is disposed toward transparent plate 120 and is configured to capture an image of the backside of wafer 180 positioned on support portion 112 through transparent plate 120 and cavity 113. Optical module 130 may be a conventional microscope 131 with microscopic imaging capabilities, which is secured to module base plate 170 via microscope mounting plate 131B, with objective lens 131A positioned opposite through-hole 111.

[0062] like Figure 4 and Figure 7 As shown, the moving module 140 is disposed on the support head 110 and / or the optical module 130 and is used to drive the support head 110 and the optical module 130 to move relative to each other to adjust the distance between the optical module 130 and the wafer 180. In other words, the moving module 140 can drive at least one of the support head 110 and the optical module 130 to move so that the bottom surface of the wafer 180 is always within the depth of field of the optical module 130.

[0063] The overall concept of this embodiment is as follows: the wafer 180 is placed face up on the support portion 112 of the support head 110, with the blue film adhered to the back thereof facing the cavity 113 formed between the transparent plate 120 and the through hole 111; after a transparent liquid 190 is injected into the cavity 113, the liquid fills the microscopic concave and convex structures on the surface of the blue film 181, eliminating diffuse reflection of light and converting the blue film 181 from a frosted state to an optically transparent state; the optical module 130 obtains an image of the back of the wafer 180 through the transparent plate 120 and the liquid, effectively solving the problem of being unable to clearly obtain an image due to the blue film 181, and improving the accuracy and reliability of defect detection on the back of the wafer 180. Among them, the wafer 180 is placed on the support portion 112 of the support head 110, and the support head 110 provides stable and reliable support for the wafer 180, preventing the wafer 180 from sagging due to its own gravity. In this way, under the drive of the moving module 140, the optical module 130 can accurately adjust the distance between itself and the wafer 180, so that the bottom surface of the wafer 180 is always within the depth of field of the optical module 130, thereby being able to clearly image the back side of the wafer 180 and achieve high-magnification, high-precision automated detection of back side defects without flipping the wafer 180.

[0064] Figure 9 is a cross-sectional perspective view of a support head according to one embodiment of the present disclosure.

[0065] See Figure 6 and Figure 9 As shown, the above-mentioned transparent plate 120 can be arranged in the through hole 111 of the support head 110 in the following manner: the inner wall of the through hole 111 is provided with a stepped groove 110C, the outer periphery of the transparent plate 120 is embedded in the stepped groove 110C, and the lower surface of the transparent plate 120 is in contact with the step surface of the stepped groove 110C to form axial limitation and radial constraint.

[0066] like Figure 6 and Figure 9 As shown, in order to facilitate the injection of a transparent solution into the storage cavity 113, the support head 110 is provided with an injection channel. The injection channel includes an injection interface 114 and a first communicating hole 115 that are connected in sequence, and the first communicating hole 115 extends to the storage cavity 113. The injection interface 114 can be installed with an injection joint, and the injection joint is connected to an injection device through a pipeline, and a transparent liquid 190 is injected into the storage cavity 113 through the injection device. When it is necessary to inject the transparent liquid 190 into the storage cavity 113, the injection device is connected to the injection interface 114, and the transparent liquid 190 enters the first communicating hole 115 through the injection interface 114, and then flows into the storage cavity 113 through the first communicating hole 115, thereby completing the injection operation of the transparent liquid 190 into the storage cavity 113. During detection, after placing the wafer 180 on the support part 112, the transparent liquid 190 can be injected into the cavity 113 through the liquid injection channel, without having to pre-inject the transparent liquid 190 and then place the wafer 180. This makes the operation more convenient and enables the transparent liquid 190 to stably and fully fill the microscopic concave-convex structure on the surface of the blue film 181, thereby improving the accuracy and stability of the detection.

[0067] like Figure 6 and Figure 9As shown, in the process of collecting images of the back side of the wafer 180, the images of different areas on the back side of the wafer 180 can be collected by controlling the relative movement of the wafer 180 and the device. During the movement of the wafer 180, the liquid remaining on the back side of the wafer 180 may drip onto the electrical components of the device, causing damage to the device. In order to solve this problem, the support head 110 is provided with an annular boss 116 and a water storage tank 117 around the outer periphery of the through hole 111. The annular boss 116 constitutes the support part 112, which carries the wafer 180 during detection and can scrape off the residual liquid on the back side of the wafer 180 during the movement of the wafer 180. The water storage tank 117 is annular, and a water absorption ring 117A made of water absorption material is provided inside. The water absorption ring 117A is located on the outer periphery of the annular boss 116, and can be a microporous water absorption ring 117A or other existing annular components with water absorption function. The support head 110 is also provided with a liquid outlet channel, which includes a liquid outlet interface 118 and a second connecting hole 119. One end of the second connecting hole 119 is connected to the water storage tank 117, and the other end is connected to the liquid outlet interface 118. When the liquid in the cavity 113 overflows or there is excess liquid on the surface of the blue film 181, the annular boss 116 can scrape the residual liquid on the back of the wafer 180 on its outer side to the water absorption ring 117A. The water absorption ring 117A can absorb the scraped liquid to prevent the liquid remaining on the back of the wafer 180 from dripping and damaging the electrical components, and can solve the problem of residual bubbles in the water film. At the same time, if it is necessary to discharge the liquid, a water pump or other liquid extraction equipment can be connected through the liquid outlet interface 118 to discharge the liquid from the liquid outlet interface 118 to the outside of the equipment through the water absorption ring 117A and the second connecting hole 119, so as to keep the detection device clean and operate normally and improve the reliability and stability of the detection.

[0068] like Figure 9 As shown, in some embodiments of the support head 110 , the support head 110 is further provided with a convex ring structure 110A. The convex ring structure 110A is annular, and a water storage tank 117 is formed inside the convex ring structure 110A, which is also used to support the wafer 180 .

[0069] Figure 10 is a schematic structural diagram of a first liquid return component according to an embodiment of the present disclosure, Figure 11 is a schematic structural diagram of a second liquid return component according to an embodiment of the present disclosure, Figure 12 FIG. 4 is a top view of a second liquid return component according to one embodiment of the present disclosure.

[0070] See Figure 6 、 Figure 10 、 Figure 11 and Figure 12As shown, in order to facilitate the collection and discharge of the transparent liquid 190 overflowing from the cavity 113 and being scraped off by the annular boss 116, the support head 110 is provided with a slot 110B on the periphery of the cavity 113, and the back detection device 100 also includes a first liquid return component 150 and a second liquid return component 160. The slot 110B is used to collect the transparent liquid 190 overflowing from the cavity 113 and being scraped off by the annular boss 116. The first liquid return component 150 is provided at the lower end of the support head 110 and is provided with a V-shaped groove 151 and a side hole 152. The V-shaped groove 151 is opposite to the slot 110B and is located below the slot 110B. It can be an annular structure with a V-shaped cross section. The V-shaped groove 151 is used to receive the transparent liquid 190 falling from the slot 110B. One end of the side hole 152 is connected to the V-shaped groove 151, and the other end extends to the outside of the first liquid return component 150, used to drain the transparent liquid 190 in the V-shaped groove 151. The second liquid return component 160 is disposed at the lower end of the first liquid return component 150 and is provided with a square groove 161 and a first liquid discharge port 162 connected to the square groove 161. The transparent liquid 190 overflowing from the chamber 113 is discharged sequentially through the slot 110B, the V-shaped groove 151, the side hole 152, the square groove 161, and the first liquid discharge port 162, forming a stepped liquid return path. Furthermore, the first liquid return component 150 is provided with a first clearance hole 153 positioned opposite the through hole 111, and the second liquid return component 160 is provided with a second clearance hole 163 positioned opposite the first clearance hole 153. In other words, when the through hole 111, the first clearance hole 153, and the second clearance hole 163 are circular holes, they are coaxial. When inspecting the back side of the wafer 180 , the optical module 130 acquires an image of the wafer 180 carried on the supporting portion 112 through the first clearance hole 153 and the second clearance hole 163 .

[0071] like Figure 11 and Figure 12 As shown, in some embodiments of the second liquid return component 160, a step 164 is provided at the bottom of the square groove 161. The step 164 is provided with a second liquid drainage port 165. The second liquid drainage port 165 is higher than the first liquid drainage port 162 and lower than the top of the square groove 161. The second liquid drainage port 165 is connected to an overflow pipe 166. When the liquid level in the square groove 161 rises to a certain height due to blockage of the first liquid drainage port or excessive liquid inflow, exceeding the second liquid drainage port 165, the liquid will be discharged from the second liquid drainage port 165 through the overflow pipe 166, forming a secondary drainage mechanism, preventing liquid from overflowing the square groove 161, avoiding damage to the detection device, and improving the reliability and safety of the device.

[0072] like Figure 7 and Figure 12As shown, in order to integrate the above-mentioned structure for transporting and draining transparent liquid 190 into the device, the second liquid return component 160 is further provided with two pipe interfaces 169. One pipe interface 169 is connected to the connector on the liquid injection interface 114 via a pipe connector and a hose, and the other pipe interface 169 is connected to the connector on the liquid discharge interface 118 via a pipe connector and a hose. At the same time, the first and second liquid discharge ports are also provided with connectors, which are connected to the hoses through the connectors to discharge the transparent liquid 190.

[0073] In one embodiment, the above-mentioned first liquid return component 150 is arranged at the lower end of the support head 110, and an internal thread is provided on the inner side of the through hole 111 to form an internal threaded hole. The first liquid return component 150 is provided with an external threaded shaft 154 adapted to the internal threaded hole in the middle of the V-groove 151. The external threaded shaft 154 is connected to the inner side of the internal threaded hole through a thread, and the first clearance hole 153 passes through the external threaded shaft 154.

[0074] In one embodiment in which the second liquid return component 160 is arranged at the lower end of the first liquid return component 150, the second liquid return component 160 is provided with an annular mounting groove 167 surrounding the outer periphery of the second clearance hole 163, and a sealing ring 168 is provided in the annular mounting groove 167; the first liquid return component 150 is fixedly arranged on the upper end surface of the second liquid return component 160, and is sealed with the second liquid return component 160 through the sealing ring 168.

[0075] In one embodiment of the movable module 140, the movable module 140 includes a bracket 141, an adapter block 142, and a height adjustment shaft 143, which are connected in sequence. The bracket 141 is positioned at the lower end of the second liquid return component 160. The height adjustment shaft 143 is used to drive the adapter block 142, the bracket 141, the second liquid return component 160, the first liquid return component 150, and the support head 110 to move up and down to adjust the distance between the optical module 130 and the wafer 180. The bracket 141 is L-shaped and has a third clearance hole 141A positioned opposite the first clearance hole 153. The height adjustment shaft 143 drives the adapter block 142 up and down, thereby driving the entire movement of the bracket 141, the liquid return component, and the support head 110. The third clearance hole 141A is coaxial with the first and second clearance holes to ensure an unobstructed optical path for the optical module 130.

[0076] It is understandable that the moving module 140 may also use an existing device such as a lifting mechanism or a linear moving module 140 that can drive the support head 110 and the optical module 130 to move relative to each other.

[0077] like Figure 1 and Figure 2As shown, the front inspection device 200 is disposed above the wafer stage 300 and is used to detect front defects of the wafer on the wafer stage 300. The front inspection device 200 can be an existing device with an image acquisition function such as a microscope and is disposed toward the wafer stage 300.

[0078] See Figures 1 to 3 As shown, the wafer inspection apparatus further includes a first drive mechanism 500 and a first height adjustment mechanism 800 disposed between the base platform 400 and the front inspection device 200. The first drive mechanism 500 and the first height adjustment mechanism 800 are interconnected. The first drive mechanism 500 is used to drive the front inspection device 200 to move in a first horizontal direction, and the first height adjustment mechanism 800 is used to drive the front inspection device 200 to move up and down. The wafer inspection apparatus further includes a second drive mechanism 600 and a second height adjustment mechanism 900 disposed between the base platform 400 and the back inspection device 100. The second drive mechanism 600 and the second height adjustment mechanism 900 are interconnected and are used to drive the back inspection device to move in a first horizontal direction and a vertical direction, respectively. The wafer inspection apparatus further includes a stage drive mechanism 700 disposed between the base platform 400 and the wafer carrier 300. The stage drive mechanism 700 is used to drive the wafer carrier to move in a second horizontal direction. The first horizontal direction and the second horizontal direction are perpendicular to each other. In the figure, the first horizontal direction and the second horizontal direction are exemplified by the X-axis and the Y-axis, respectively. The first height adjustment mechanism 800 and the second height adjustment mechanism 900 may use a height adjustment shaft or an existing lifting module.

[0079] Figure 13 is a perspective view of a wafer stage according to one embodiment of the present disclosure, Figure 14 is a perspective view of a wafer stage according to one embodiment of the present disclosure.

[0080] like Figure 13 and Figure 14As shown, the wafer carrier 300 includes: a base 310, a carrier body 320, a multi-axis guide mechanism 324, a third drive mechanism 325 and a fourth drive mechanism 326. The base 310 is movably arranged on the base platform 400 and is connected to the carrier drive mechanism 700. The carrier body 320 is movably arranged above the base 310 and is provided with a positioning ring 321 for positioning the wafer, a material receiving assembly 322 for receiving the positioning ring 321 and a fixing assembly 323 for fixing the positioning ring 321. The fixing assembly 323 can be an existing clamping assembly, such as a pneumatic clamp. The material receiving assembly 322 can use an existing lifting mechanism and has a plurality of lifting rods 322A that can be raised and lowered. The base 310 is provided with a clearance hole for the lifting rods 322A. When the lifting rods 322A rise, they receive the positioning ring 321, and when they fall, they place the positioning ring 321 on the carrier body 320. The multi-axis guide mechanism 324 is mounted on the base 310 and includes a guide head 324A. This guide head 324A is rotatably connected to the stage body 320 and has the freedom to move in first and second horizontal directions, as well as rotation about a vertical axis. A third drive mechanism 325 and a fourth drive mechanism 326 are mounted between the base 310 and the stage body 320, respectively, to drive the guide head 324A in the first and second horizontal directions, allowing each multi-axis guide mechanism 324 to automatically adjust its displacement and rotation angle. The base 310 is moved in the X-axis direction by the stage drive mechanism 700, while the guide head 324A is moved in the X-axis direction by the third drive mechanism 325 and in the Y-axis direction by the fourth drive mechanism 326, driving the stage body 320 to rotate and achieve position correction. The multi-axis guide mechanism 324 can utilize an existing XYθ-axis guide module. The beneficial effects of this structure are: the multi-axis guiding mechanism 324 enables the carrier body 320 to fine-tune the three degrees of freedom of X, Y, and θ, and accurately correct the angular deviation between the wafer cutting path and the detection coordinate system; the positioning ring 321 and the fixing component 323 ensure that the wafer remains stable during the detection process to prevent image blur caused by vibration; this design corrects the wafer through precise coordinate system correction, preparing for wafer position correction.

[0081] Figure 17 is an exploded view of a first height adjustment mechanism according to one embodiment of the present disclosure.

[0082] like Figure 17As shown, in one embodiment of the first height adjustment mechanism 800, the first height adjustment mechanism 800 is composed of a ball screw mechanism 810, an LM guide 820, a servo motor 830, a base plate 840, three side plates 850, a nut seat 860, a motor mounting plate 870, a first movable plate 880, and a coupling 890. The base plate 840, the three side plates 850, the nut seat 860, and the motor mounting plate 870 are connected to form a mounting frame, the servo motor 830 is mounted on the motor mounting plate 870, and is connected to the ball screw mechanism 810 through the coupling 890, the movable plate 880 is connected to the ball screw mechanism 810 through the nut seat 860, and the LM guide 820 is connected to the nut seat 860 for guiding the movable plate 880. During installation, the movable plate 880 is connected to a driven component, such as a front detection device. It is understandable that the second height adjustment mechanism 900 can use the same mechanism as the first height adjustment mechanism 800 to achieve a height adjustment function.

[0083] Figure 15 is an exploded view of a first drive mechanism according to one embodiment of the present disclosure.

[0084] like Figure 15 As shown, in one embodiment of the first drive mechanism 500, it is composed of a marble pad 501, a marble guide rail 502, several air-floating foot cups 503, four foot cup mounting plates 504, a linear motor 505, and a limit block 506, which is used to drive the front detection device to move along the X direction. Among them, the marble pad 501 is mounted on the base platform 400, the marble guide rail 502 is mounted on the marble pad 501, and the foot cup mounting plates 504 are connected to each other and are used to mount the air-floating foot cups 503, which serve as a support. The linear motor 505 is mounted on the marble pad 501 and drives the foot cup mounting plate 504 to move along the marble guide rail 502. The limit block 506 is mounted on one side of the marble guide rail 502 to limit the maximum travel range. During installation, one of the foot cup mounting plates 504 is connected to the first height adjustment mechanism 800.

[0085] Figure 16 is a perspective view of a second driving mechanism according to one embodiment of the present disclosure.

[0086] like Figure 16As shown, in one embodiment of the second drive mechanism 600, the second drive mechanism 600 comprises a marble base 610, an X-guide rail 620, a second linear motor 630, a second movable plate 640, and a second stop block 650, and is used to drive the backside inspection device to move along the X-axis. The second linear motor 630 and the X-guide rail 620 are mounted on the marble base 610, the second movable plate 640 is connected to the second linear motor 630 and the second height adjustment mechanism 900, and is guided by the X-guide rail 620, while the second stop block 650 limits the travel of the second movable plate 640.

[0087] Figure 18 is a perspective view of a stage driving mechanism according to one embodiment of the present disclosure.

[0088] like Figure 18 As shown, the stage drive mechanism 700 comprises a Y-axis guide rail 710, a third linear motor 720, and a third stopper 730, and is used to drive the wafer stage along the Y-axis. The Y-axis guide rail 710 and the third linear motor 720 are mounted on the base platform 400. The third linear motor 720 drives the base 310 of the wafer stage 300, and the third stopper 730 limits the travel of the base 310.

[0089] This embodiment provides a wafer inspection method, using the above-mentioned wafer inspection equipment, including the following steps: fixing the wafer on the wafer carrier; supporting the wafer by a support part, and allowing the transparent liquid filled in the cavity to infiltrate the outer surface of the blue film on the back of the wafer; and detecting the front defects and back defects of the wafer respectively by a front inspection device and a back inspection device.

[0090] Specifically, the wafer inspection method includes the following steps: Step 1: Fix the wafer on the wafer stage.

[0091] Step 2: Drive the wafer stage to move along the second horizontal direction through the stage driving mechanism, and drive the front detection device to move along the first horizontal direction through the first driving mechanism, and capture multiple feature points on the front side of the wafer through the front detection device; calculate the angular deviation value between the wafer cutting path and the detection coordinate system; drive the stage body to move through the third driving mechanism and the fourth driving mechanism, and guide it through the multi-axis guiding mechanism, so as to correct the position of the wafer and establish the wafer surface coordinate system.

[0092] Step 3: Drive the back detection device to move to the bottom of the back of the wafer along the first horizontal direction through the second driving mechanism; drive the support head to rise to contact and support the outer surface of the blue film on the back of the wafer.

[0093] Step 4: Add transparent liquid into the cavity through the liquid injection channel, so that the transparent liquid forms a liquid film under the action of surface tension and infiltrates the outer surface of the blue film to eliminate light scattering.

[0094] Step 5: Control the back side inspection device to move along the scanning path and collect a complete image of the back side of the wafer through the optical module.

[0095] Step 6: Drive the front detection device to move along the first horizontal direction to above the front of the wafer through the first drive mechanism; control the front detection device to move along the scanning path to capture a complete image of the front of the wafer; during the acquisition process, monitor the sagging state of the blue film of the wafer in real time. When the sagging amount exceeds the depth of field of the objective lens, drive the support head to support the wafer through the second height adjustment mechanism, and drive the support head to move synchronously with the moving trajectory of the front detection device through the second drive mechanism to maintain the flatness of the back of the wafer. In this case, a master-slave control algorithm can be used, where the mobile module of the back detection device receives the motion trajectory signal of the front detection device and synchronously adjusts the position of the support head at the same speed and direction.

[0096] Step 7: Transmit the front and back images to the image processing system for defect detection and comparison analysis.

[0097] Among them, wafer front-side inspection and back-side inspection can be performed separately or simultaneously, which is suitable for different inspection scenarios.

[0098] Real-time monitoring of the sagging state of the blue film on the wafer can be achieved by detecting the collected images, or by using a laser displacement sensor installed on the support head to collect the blue film surface morphology data in real time, calculate the sagging amount and compare it with the depth of field threshold of the objective lens.

[0099] The above wafer inspection method is compatible with both front and back side inspections, avoiding the tedious operation of flipping the wafer required by traditional methods. The wafer is supported by a support part and moves synchronously with the front side inspection device, so that the amount of sagging during inspection is less than the depth of field of the objective lens. At the same time, it realizes the standardization and automation of the through-film inspection process, improves inspection efficiency, and provides an efficient and reliable solution for quality control in the wafer manufacturing process.

[0100] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments / methods or examples. In addition, those skilled in the art may combine and combine different embodiments / methods or examples described in this specification and the features of different embodiments / methods or examples, unless they are contradictory.

[0101] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0102] Those skilled in the art will appreciate that the above embodiments are merely intended to clearly illustrate the present disclosure and are not intended to limit the scope of the present disclosure. Other changes or modifications may be made based on the above disclosure, and such changes or modifications are still within the scope of the present disclosure.

Claims

1. A wafer inspection device, characterized in that: include: base platform; A wafer carrier, movably disposed on the base platform, for fixing the wafer; A front surface detection device, disposed above the wafer stage, for detecting front surface defects of the wafer on the wafer stage; A back-side detection device is arranged below the wafer stage and is used to detect defects on the back side of the wafer. The back-side detection device includes a supporting portion for supporting the wafer, and a cavity for accommodating a transparent liquid is formed in the supporting portion. The transparent liquid is used to infiltrate the outer surface of the blue film on the back side of the wafer.

2. The wafer inspection device according to claim 1, characterized in that: The back detection device comprises: A support head having a through hole provided therein, wherein the upper end of the hole wall of the through hole forms the support portion for supporting the wafer; a transparent plate made of a transparent material and disposed in the through hole, wherein the upper surface of the transparent plate is lower than the upper end surface of the through hole, so that the cavity is formed between the outer surface of the transparent plate and the inner wall surface of the through hole; an optical module, disposed below the support head and facing the transparent plate, for acquiring an image of the back side of the wafer on the support portion through the transparent plate and the cavity; The moving module is provided on the supporting head and / or the optical module, and is used for driving the supporting head and the optical module to move relative to each other so as to adjust the distance between the optical module and the wafer.

3. The wafer inspection device according to claim 2, characterized in that: The support head is provided with a liquid injection channel, the liquid injection channel includes a liquid injection interface and a first communicating hole connected in sequence, and the first communicating hole extends to the cavity; The support head is provided with an annular boss and a water storage tank around the periphery of the through hole, the annular boss constitutes the support portion, the water storage tank is located on the outer periphery of the annular boss and is provided with a water absorption ring made of water absorption material; The support head is further provided with a liquid outlet channel, which includes a liquid outlet interface and a second communicating hole, one end of the second communicating hole is connected to the water storage tank, and the other end is connected to the liquid outlet interface.

4. The wafer inspection device according to claim 3, characterized in that: The support head is provided with slots on the periphery of the cavity; The back detection device further includes a first liquid return component and a second liquid return component; The first liquid return component is arranged at the lower end of the support head and is provided with a V-shaped groove and a side hole, the V-shaped groove is opposite to the groove hole, one end of the side hole is connected to the V-shaped groove, and the other end extends to the outside of the first liquid return component, and the first liquid return component is provided with a first clearance hole opposite to the through hole; The second liquid return component is arranged at the lower end of the first liquid return component and is provided with a square groove and a first liquid discharge interface connected to the square groove. The second liquid return component is provided with a second clearance hole opposite to the first clearance hole. The optical module obtains an image of the wafer carried on the support portion through the first clearance hole and the second clearance hole.

5. The wafer inspection equipment according to claim 4, characterized in that: The bottom of the square trough is provided with a step, and the step is provided with a second liquid drainage interface. The height of the second liquid drainage interface is higher than the first liquid drainage interface and lower than the top of the square trough, and is connected to an overflow pipe.

6. The wafer inspection device according to claim 4, characterized in that: The movable module includes a bracket, an adapter block and a height adjustment shaft connected in sequence, and the bracket is arranged at the lower end of the second liquid return component; the height adjustment shaft is used to drive the adapter block, the bracket, the second liquid return component, the first liquid return component and the support head to move up and down to adjust the distance between the optical module and the wafer; wherein, the bracket is provided with a third clearance hole opposite to the position of the first clearance hole.

7. The wafer inspection device according to claim 1, characterized in that: The wafer inspection device further includes a first driving mechanism and a first height adjustment mechanism disposed between the base platform and the front inspection device, the first driving mechanism and the first height adjustment mechanism being connected to each other and respectively used to drive the front inspection device to move in a first horizontal direction and a vertical direction; The wafer inspection device further includes a second driving mechanism and a second height adjustment mechanism disposed between the base platform and the backside inspection device, the second driving mechanism and the second height adjustment mechanism being connected to each other and respectively used to drive the backside inspection device to move in a first horizontal direction and a vertical direction; The wafer inspection device further includes a stage driving mechanism disposed between the base platform and the wafer stage, the stage driving mechanism being configured to drive the wafer stage to move along a second horizontal direction; The first horizontal direction and the second horizontal direction are perpendicular to each other.

8. The wafer inspection device according to claim 7, characterized in that: The wafer stage comprises: A base, movably disposed on the base platform and connected to the stage driving mechanism; The carrier body is movably arranged above the base and is provided with a positioning ring for positioning the wafer, a receiving assembly for receiving the positioning ring, and a fixing assembly for fixing the positioning ring; a multi-axis guide mechanism provided on the base, the multi-axis guide mechanism being provided with a guide head, the guide head being connected to the stage body and having a degree of freedom of movement along a first horizontal direction and a second horizontal direction and a degree of freedom of rotation about a vertical axis; The third driving mechanism and the fourth driving mechanism, which are arranged between the base and the platform body, are used to drive the guide head to move along the first horizontal direction and the second horizontal direction, respectively.

9. A wafer detection method, characterized in that: The wafer inspection device according to any one of claims 1 to 8 comprises the following steps: Fixing the wafer on the wafer stage; The wafer is supported by a supporting portion, and the transparent liquid filled in the cavity is allowed to soak the outer surface of the blue film on the back of the wafer; The front side defects and the back side defects of the wafer are detected respectively by a front side detection device and a back side detection device.

10. The wafer detection method according to claim 9, characterized in that: After the wafer is fixed on the wafer stage, and before the front side defects and back side defects of the wafer are respectively detected by the front side detection device and the back side detection device, the following steps are further included: driving the wafer stage to move along the second horizontal direction and driving the front detection device to move along the first horizontal direction, capturing feature points on the front side of the wafer, calculating the angular deviation between the wafer cutting path and the detection coordinate system, and correcting the position of the wafer stage through the multi-axis guide mechanism to establish a wafer surface coordinate system; Driving the backside inspection device to move along the first horizontal direction to below the wafer stage, so that the support head rises to contact and support the outer surface of the blue film; Adding transparent liquid into the cavity through the liquid injection channel of the support head, so that the transparent liquid infiltrates the outer surface of the blue film; The detecting of front defects and back defects of the wafer by a front detection device and a back detection device respectively comprises the following steps: Controlling the backside detection device to move along a scanning path and collecting a complete image of the backside of the wafer through an optical module; The front inspection device is driven to move along a first horizontal direction to above the wafer stage, and the front inspection device is controlled to move along a scanning path to capture a complete image of the front side of the wafer. When the sagging amount exceeds the depth of field of the objective lens, the support head is driven to move synchronously with the moving trajectory of the front inspection device to maintain the back side of the wafer flat and the surface is within the depth of field of the back side inspection device. The wafer front and back images are transmitted to the image processing system for defect detection and comparison analysis.

Images