Wafer detection equipment

Abstract

The invention discloses wafer detection equipment, and mainly relates to the technical field of wafer detection equipment. The wafer detection equipment comprises a wafer adsorption device, an optical machine assembly, a mounting seat and a mobile platform. The wafer adsorption device is used for receiving wafers and comprises a vacuum chuck, a wafer receiving assembly, an adsorption assembly and an air disc. The wafer is adsorbed on the upper surface of the vacuum chuck through the wafer adsorption device, so that the lower surface of the wafer is attached to the flat upper surface of the vacuum chuck, the surface of the warped wafer is flatter, the detection requirement of defect detection can be met, and the accuracy of a detection result is improved; and then the wafer is adsorbed and leveled through the adsorption assembly, so that the wafer can be fixed before adsorption work, displacement of the wafer caused by non-uniform adsorption force is prevented, and the reliability is improved. The position and angle of the wafer relative to the lens can be adjusted through the mobile platform according to actual detection requirements, and the automation degree is high.

Description

Technical Field

[0001] This invention relates to the field of wafer inspection equipment technology, and more particularly to a wafer inspection device. Background Technology

[0002] After the wafer (including but not limited to other substrates) is fabricated, it usually needs to undergo multiple processes such as defect detection or dimensional measurement.

[0003] Ensuring the flatness of the wafer surface during wafer metrology can improve measurement efficiency and accuracy.

[0004] During defect inspection, wafers are typically first fixed to a vacuum chuck using an adsorption method, and then inspected for defects using optical inspection equipment. However, some wafers undergoing inspection exhibit significant warping. Conventional vacuum chucks cannot properly hold these warped wafers flat, preventing the inspection equipment from detecting this type of wafer. Uneven adsorption leads to unclear optical imaging, making wafer inspection impossible.

[0005] Because wafers are thin and expensive, the surface flatness error of the wafers needs to meet the actual testing requirements in order to ensure the accuracy of defect detection, without damaging the wafers. Existing equipment usually cannot meet the above flatness requirements when adsorbing wafers with large warpage. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a wafer inspection device to improve the flatness of wafers during inspection, thereby improving the accuracy of defect detection results.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A wafer inspection device, comprising:

[0009] A wafer adsorption device for receiving wafers includes:

[0010] Vacuum chucks have a flat upper surface and are used to flatten the wafer surface after it is bonded to them.

[0011] A wafer receiving assembly, wherein a portion of the wafer receiving assembly is elliptical and movably mounted on the vacuum chuck for receiving wafers;

[0012] An adsorption component is provided on the vacuum chuck to adsorb the wafer received by the bonding assembly, so that the wafer is attached to the upper surface of the vacuum chuck.

[0013] An air plate is used to be positioned below the vacuum suction cup to provide a vacuum channel for at least a portion of the adsorption assembly.

[0014] An optomechanical assembly is positioned above the wafer adsorption device for wafer inspection.

[0015] Mounting base, the wafer adsorption device is disposed on the mounting base, and the mounting base is used to fix the wafer adsorption device;

[0016] A mobile platform, wherein the mounting base is disposed on the mobile platform, and the mobile platform is used to adjust the spatial position and angle of the target wafer relative to the optomechanical assembly.

[0017] Furthermore, the mobile platform includes:

[0018] A rotating component is provided at the bottom of the mounting base to drive the wafer adsorption device to rotate, thereby adjusting the detection angle of the wafer relative to the optomechanical component.

[0019] A Z-axis moving component is provided on the rotating component to drive the wafer adsorption device to move in the Z-axis direction.

[0020] A Y-axis moving component is provided on the Z-axis moving component to drive the wafer adsorption device to move in the Y-axis direction.

[0021] An X-axis moving component is disposed on the Y-axis moving component and is used to drive the wafer adsorption device to move in the X-axis direction.

[0022] The X-axis, Y-axis, and Z-axis are perpendicular to each other, and the Z-axis is parallel to the thickness direction of the vacuum chuck.

[0023] Furthermore, several support columns are provided between the vacuum suction cup and the air plate;

[0024] The optical-mechanical assembly includes: a lens, a camera, and a light source;

[0025] The wafer inspection equipment further includes a controller, which is communicatively connected to the wafer adsorption device, the optomechanical component, and the moving platform to control the operation of the wafer adsorption device, the optomechanical component, and the moving platform, and to inspect the wafer.

[0026] Furthermore, the vacuum suction cup is provided with a plurality of first through holes extending vertically, and the contact assembly includes:

[0027] A plurality of splice nozzles, each of which is vertically and vertically pass through a first through-hole for descending after adsorbing and receiving a wafer, so that the lower surface of the wafer approaches the upper surface of the vacuum chuck.

[0028] A lifting drive mechanism is used to connect each of the splice nozzles and to drive the splice nozzles to rise and fall so that the splice nozzles extend out of or retract into the first through hole.

[0029] Furthermore, the vacuum suction cup is provided with several second through holes extending vertically, and the air plate is provided with several first adsorption air channels. The adsorption assembly includes:

[0030] A plurality of vacuum nozzles, each of which is disposed in a second through hole, and the upper end of the vacuum nozzle protrudes from the upper surface of the vacuum chuck, for adsorbing wafers;

[0031] A plurality of air tubes, each of the air tubes being connected to the lower end of a vacuum nozzle, and the end of each air tube away from the vacuum nozzle being connected to a first adsorption air channel on the air plate;

[0032] A plurality of first vacuum ports are disposed on the air plate, each first vacuum port being used to connect to one or more air pipes through a first adsorption air channel to provide a vacuuming channel for the vacuum nozzle.

[0033] Furthermore, the plurality of vacuum nozzles are divided into multiple groups along the radial direction of the vacuum suction cup. Each group of vacuum nozzles includes multiple vacuum nozzles located on the same circumference. The multiple vacuum nozzles are distributed at intervals on the same circumference, and the circumferences of the multiple groups of vacuum nozzles are all concentric with the vacuum suction cup.

[0034] Furthermore, the vacuum nozzle includes, along its length, a suction section, a deformable section, and a connecting section. The suction section is used to suction the wafer; the deformable section is used to deform and shrink after the suction section suctions the wafer, so that the upper end of the suction section shrinks to be flush with the upper surface of the vacuum suction cup; and the connecting section is used to connect the air tube; and / or,

[0035] Both the suction part and the deformable part of the vacuum nozzle are made of soft material; and / or,

[0036] The lower end of the vacuum nozzle is connected to the air tube via a buffer mechanism. The buffer mechanism has a buffer stroke along the axial direction of the vacuum nozzle to allow the vacuum nozzle to adapt to different warpages of the wafer.

[0037] Furthermore, the wafer adsorption device also includes a first vacuum connector, which is connected to the plurality of first vacuum interfaces via pipes. The pipes between the first vacuum connector and each first vacuum interface are of the same length. Each first vacuum interface is connected to the same plurality of gas pipes. The length of the first adsorption gas channel between each first vacuum interface and each connected gas pipe is the same. The length of each gas pipe is the same, so that the length of the vacuuming channel between the first vacuum connector and each vacuum nozzle is the same.

[0038] Furthermore, the vacuum chuck is provided with a plurality of second adsorption channels, and the upper surface of the vacuum chuck is provided with a plurality of annular vacuum channels concentric with the vacuum chuck. The annular vacuum channels are used to adsorb wafers. The adsorption assembly also includes:

[0039] A plurality of second vacuum ports are disposed on the vacuum suction cup, each second vacuum port being used to connect to one or more annular vacuum channels through a second adsorption air channel.

[0040] Furthermore, the upper surface of the vacuum suction cup is provided with several branch air channels, which are evenly distributed on the several annular vacuum channels.

[0041] The plurality of annular vacuum channels are not interconnected, or adjacent annular vacuum channels are connected by branch channels; and / or,

[0042] The wafer adsorption device further includes a second vacuum connector, which is connected to the plurality of second vacuum interfaces via pipes. The pipes between the second vacuum connector and each second vacuum interface are of the same length. The second adsorption gas channel is a straight gas channel. One end of the second adsorption gas channel is connected to a second vacuum interface, and the other end of the second adsorption gas channel is connected to an annular vacuum channel through a through hole on the vacuum suction cup. The annular vacuum channel is connected to the plurality of second vacuum interfaces through the plurality of second adsorption gas channels. The through holes between the annular vacuum channel and the plurality of second adsorption gas channels are evenly spaced along the annular vacuum channel so that the length of the vacuum channel between the second vacuum connector and the plurality of through holes of the same annular vacuum channel is the same.

[0043] The second adsorption channels corresponding to the same annular vacuum channel are located in the same thickness plane of the vacuum suction cup, while the second adsorption channels corresponding to different annular vacuum channels are located in different thickness planes of the vacuum suction cup.

[0044] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0045] In the wafer inspection equipment of the present invention, the wafer is adsorbed onto the upper surface of the vacuum chuck by the adsorption component in the wafer adsorption device, so that the lower surface of the wafer is in contact with the flat upper surface of the vacuum chuck, thereby making the warped wafer surface flatter and meeting the inspection requirements for defect detection, thus improving the accuracy of the inspection results. In addition, the wafer adsorption device of the present invention first receives the wafer through the bonding component, and then adsorbs and flattens the wafer through the adsorption component, which can fix the wafer before adsorption and prevent the wafer from shifting due to uneven adsorption force, thus improving the reliability of the equipment.

[0046] Furthermore, the wafer inspection equipment of the present invention can automatically adjust the position and angle of the wafer adsorption device through the moving platform, thereby adjusting the position and angle of the wafer relative to the lens according to the actual inspection requirements. It has a high degree of automation and improves practicality. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the structure of a wafer inspection device according to an embodiment of the present invention;

[0048] Figure 2 This is a three-dimensional structural schematic diagram of the wafer adsorption device in an embodiment of the present invention;

[0049] Figure 3 This is a partially exploded structural diagram of the wafer adsorption device in an embodiment of the present invention from a first-view perspective;

[0050] Figure 4 This is a partially exploded structural diagram of the wafer adsorption device in an embodiment of the present invention from a second perspective.

[0051] Figure 5 This is a schematic diagram of the main structure of the wafer adsorption device in an embodiment of the present invention;

[0052] Figure 6 This is a top view schematic diagram of the wafer adsorption device in an embodiment of the present invention;

[0053] Figure 7 This is a schematic diagram of the structure of the vacuum chuck along the radial section in an embodiment of the present invention;

[0054] Figure 8 This is a schematic diagram of the structure of the air disc along the radial section in an embodiment of the present invention;

[0055] Figure 9 This is a schematic diagram of the structure of the splice nozzle in an embodiment of the present invention;

[0056] Figure 10 This is a partial cross-sectional schematic diagram of the connection between the vacuum nozzle and the air tube via a buffer mechanism in an embodiment of the present invention.

[0057] In the diagram: 1. Vacuum suction cup; 2. Wafer assembly; 201. Wafer nozzle; 202. Lifting drive mechanism; 3. Air plate; 4. First adsorption air channel; 501. Vacuum nozzle; 502. Air pipe; 503. First vacuum interface; 504. Second vacuum interface; 6. Second adsorption air channel; 7. Annular vacuum channel; 8. Branch air channel; 9. Through hole; 10. Support column; 11. Buffer mechanism; 111. Shaft core; 112. Sleeve; 113. Spring; 12. Wafer adsorption device; 13. Optomechanical assembly; 14. Mounting base; 15. Moving platform; 16. Third vacuum interface. Detailed Implementation

[0058] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0059] The terms used to express position and direction in this invention are illustrated with reference to the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this invention.

[0060] refer to Figures 1 to 10 The wafer inspection equipment provided in this embodiment includes: a wafer adsorption device 12, an optomechanical assembly 13, a mounting base 14, and a moving platform 15.

[0061] The wafer adsorption device 12 is used to receive wafers and includes: a vacuum chuck 1, a wafer assembly 2, an adsorption assembly and a gas disk 3, and may also include a first vacuum connector and a second vacuum connector.

[0062] The vacuum chuck 1 has a flat upper surface, which is used to flatten the wafer surface after the wafer is attached to it.

[0063] Part of the wafer receiving assembly 2 is vertically mounted on the vacuum chuck 1 for receiving wafers.

[0064] The adsorption assembly is used to be mounted on the vacuum chuck 1 to adsorb the wafers held by the bonding assembly 2, so that the wafers are attached to the upper surface of the vacuum chuck 1.

[0065] The air plate 3 is positioned below the vacuum suction cup 1 to provide a vacuum channel for at least a portion of the adsorption components. Several support columns 10 are provided between the vacuum suction cup 1 and the air plate 3 to support and fix the vacuum suction cup 1. The support columns 10 separate the vacuum suction cup 1 from the air plate 3. The support columns 10 can be metal threaded columns. There can be multiple support columns 10, which are evenly distributed between the vacuum suction cup 1 and the air plate 3. The support columns 10 are connected to the vacuum suction cup 1 and the air plate 3 respectively.

[0066] The optomechanical assembly 13 is positioned above the wafer adsorption device 12 for inspecting the wafer.

[0067] The wafer adsorption device 12 is mounted on the mounting base 14, which is used to fix the wafer adsorption device 12.

[0068] Mounting base 14 is mounted on moving platform 15, which is used to adjust the spatial position and angle of the target wafer relative to optomechanical assembly 13.

[0069] The wafer inspection equipment of this embodiment uses the adsorption component in the wafer adsorption device 12 to adsorb the wafer onto the upper surface of the vacuum chuck 1, so that the lower surface of the wafer is in contact with the flat upper surface of the vacuum chuck 1, thereby making the warped wafer surface flatter and meeting the inspection requirements for defect detection, thus improving the accuracy of the inspection results. In addition, the wafer adsorption device 12 of this invention first receives the wafer through the bonding component 2, and then adsorbs and flattens the wafer through the adsorption component, which can fix the wafer before adsorption and prevent the wafer from shifting due to uneven adsorption force, thus improving the reliability of the device.

[0070] In addition, the wafer inspection equipment in this embodiment can automatically adjust the position and angle of the wafer adsorption device 12 through the moving platform 15, thereby adjusting the position and angle of the wafer relative to the lens according to the actual inspection requirements. The degree of automation is high, which is beneficial to improving practicality.

[0071] In a preferred embodiment, the mobile platform 15 includes a rotation component, a Z-axis movement component, a Y-axis movement component, and an X-axis movement component. The rotation component, the Z-axis movement component, the Y-axis movement component, and the X-axis movement component can all be driven by a motor to achieve rotation or movement.

[0072] A rotating assembly is disposed at the bottom of the mounting base 14 to drive the wafer adsorption device 12 to rotate, thereby adjusting the detection angle of the wafer relative to the optomechanical assembly 13. The rotating assembly may be a component driven by a rotary motor.

[0073] The Z-axis moving assembly is mounted on the rotating assembly and is used to drive the wafer adsorption device 12 to move in the Z-axis direction, thereby adjusting the distance between the wafer and the optomechanical assembly 13. The Z-axis moving assembly can be a component driven by a lifting mechanism.

[0074] The Y-axis moving component is set on the Z-axis moving component and is used to drive the wafer adsorption device 12 to move in the Y-axis direction, thereby adjusting the position of the wafer in the horizontal plane.

[0075] The X-axis moving component is mounted on the Y-axis moving component and is used to drive the wafer adsorption device 12 to move in the X-axis direction, thereby adjusting the position of the wafer in the horizontal plane. The X-axis moving component and the Y-axis moving component can be planar two-dimensional moving mechanical components.

[0076] The X-axis, Y-axis, and Z-axis are perpendicular to each other. The Z-axis is parallel to the thickness direction of the vacuum chuck 1. The Z-axis can be the direction of gravity.

[0077] In a preferred embodiment, the optomechanical assembly 13 includes a lens, a camera, and a light source, capable of automatically acquiring image information of the wafer under test for subsequent defect detection. Multiple lenses with different resolutions can be used. The optomechanical assembly 13, in conjunction with a controller, can be used for defect detection and wafer metrology, among other applications.

[0078] The wafer inspection equipment also includes a controller, which is communicatively connected to the wafer adsorption device 12, the optomechanical component 13, and the moving platform 15 to control the operation of the wafer adsorption device 12, the optomechanical component 13, and the moving platform 15 and to inspect the wafers. The controller can be any applicable computing device, such as a personal computer, server, programmable logic controller (PLC), microcontroller, etc., or it can be an integration of a computer device. The controller has functions such as receiving information and sending control commands.

[0079] In a preferred embodiment, the vacuum suction cup 1 is provided with a plurality of first through holes extending vertically, and the contact assembly 2 includes: a plurality of contact nozzles 201 and a lifting drive mechanism 202.

[0080] Each splice nozzle 201 can be vertically and vertically passed through a first through-hole for descending after adsorbing and receiving a wafer, so that the lower surface of the wafer approaches the upper surface of the vacuum chuck 1.

[0081] The lifting drive mechanism 202 is used to connect each wafer picker nozzle 201 and to drive the wafer picker nozzle 201 to rise and fall so that the wafer picker nozzle 201 extends or retracts from the first through hole, thereby adjusting the height of the received wafer. The lifting drive mechanism 202 can be a drive mechanism with telescopic function such as a cylinder or a hydraulic cylinder. In this invention, there are 3 wafer picker nozzles 201. The lifting drive mechanism 202 also includes an equilateral triangular support. The 3 wafer picker nozzles 201 are arranged one-to-one at the three included angles of the support. The driving end of the cylinder or hydraulic cylinder is connected to the triangular support and drives the triangular support to rise and fall, thereby driving the 3 wafer picker nozzles 201 to rise and fall. A third vacuum interface 16 is provided on the triangular bracket for connecting a vacuum device to the bonding nozzle 201 to form a vacuum air path for the bonding nozzle 201. The number of air paths for the bonding nozzle 201 can be set according to actual needs. The lifting drive mechanism 202 raises the bonding nozzle 201 to the highest position. External robotic arms or other wafer transfer equipment transfer the wafer to the top of the bonding nozzle 201. After the bonding nozzle 201 adsorbs the wafer, it descends under the action of the lifting drive mechanism 202.

[0082] In a preferred embodiment, the vacuum chuck 1 has several second through holes running vertically through it. The air plate 3 has several first adsorption air channels 4, and the vacuum chuck 1 has several second adsorption air channels 6. The upper surface of the vacuum chuck 1 has several annular vacuum channels 7 concentric with the vacuum chuck 1. These annular vacuum channels 7 are exposed and used to adsorb wafers. The annular vacuum channels 7 can also be configured as several adsorption holes, evenly distributed around the circumference of the annular vacuum channels 7. In this embodiment, four annular vacuum channels 7 can be provided on the vacuum chuck 1. The inner two annular vacuum channels 7 can be used to adsorb 6-inch and 8-inch wafers, while the outer two annular vacuum channels 7 do not need to operate, avoiding unnecessary resource waste. When the inner and outer two annular vacuum channels 7 operate simultaneously, they can be used to adsorb 12-inch wafers, making the adsorption assembly suitable for wafers of different sizes, thus increasing its flexibility. Figure 6 .

[0083] The adsorption assembly includes: a plurality of vacuum nozzles 501, a plurality of air tubes 502 and a plurality of first vacuum interfaces 503, and may also include a plurality of second vacuum interfaces 504.

[0084] Each vacuum nozzle 501 is disposed within a second through hole, and the upper end of the vacuum nozzle 501 protrudes from the upper surface of the vacuum chuck 1 for adsorbing wafers. Several vacuum nozzles 501 are radially divided into multiple groups along the vacuum chuck 1. Each group of vacuum nozzles 501 includes multiple vacuum nozzles 501 located on the same circumference, spaced apart. The circumferences of the multiple groups of vacuum nozzles 501 are all concentric with the vacuum chuck 1. Preferably, the adsorption gas path of each group of vacuum nozzles 501 can be independently controlled, which can meet the adsorption needs of 6-inch, 8-inch, and 12-inch wafers. The specific adsorption gas path can be independently or in groups according to the adsorption requirements of different wafer sizes. Combined control, for example, can be achieved by setting four sets of vacuum nozzles 501 on the vacuum chuck 1. The two inner sets and two outer sets of vacuum nozzles 501 are independently controlled. The two inner sets of vacuum nozzles 501 are used to pick up 6-inch and 8-inch wafers, while the two outer sets of vacuum nozzles 501 do not need to operate, avoiding unnecessary resource waste. When the two inner sets and two outer sets of vacuum nozzles 501 operate simultaneously, they can be used to pick up 12-inch wafers, making the adsorption assembly suitable for wafers of different sizes and providing greater flexibility. Figure 6 .

[0085] Each air tube 502 is connected to the lower end of a vacuum nozzle 501. A buffer mechanism 11 can be provided at the connection between the vacuum nozzle 501 and the air tube 502 to ensure that the vacuum nozzle 501 and the warped part of the wafer are in complete contact even when the wafer warpage is large. At the same time, it can also ensure that the wafer can still be in complete contact with the upper surface of the vacuum chuck 1 after the wafer splice nozzle 201 has descended, thereby meeting the high wafer flatness requirements. The end of each air tube 502 away from the vacuum nozzle 501 is connected to a first adsorption air channel 4 on the air plate 3.

[0086] Several first vacuum interfaces 503 are provided on the air plate 3. The first vacuum interfaces 503 are used to connect external vacuum equipment to form a vacuum air path for the vacuum nozzle 501. The number of air paths of the vacuum nozzle 501 can be set according to actual needs. Each first vacuum interface 503 is used to connect one or more air pipes 502 through the first adsorption air channel 4 to provide a vacuum channel for the vacuum nozzle 501.

[0087] Several second vacuum interfaces 504 are provided on the vacuum suction cup 1. The second vacuum interfaces 503 are used to connect external vacuum equipment to form the vacuum suction cup 1 vacuum air path. The number of air paths of the vacuum suction cup 1 can be set according to actual needs. Each second vacuum interface 504 is used to connect one or more annular vacuum air paths 7 through the second adsorption air path 6.

[0088] The upper surface of the vacuum chuck 1 is also provided with several branch air channels 8, which are evenly distributed on several annular vacuum channels 7. The several annular vacuum channels 7 are not interconnected, or adjacent several annular vacuum channels 7 are connected through the branch air channels 8. By setting the branch air channels 8, the upper surface of the vacuum chuck 1 can more evenly adsorb multiple positions of the wafer, and the adsorption force at multiple positions is uniform, thereby ensuring the flatness of the wafer.

[0089] The vacuum nozzle 501, in conjunction with the air tube 502 and air plate 3, achieves multi-point uniform adsorption. The annular vacuum channel 7, in conjunction with the branch air channels 8, enables both linear and surface adsorption. All areas of the wafer's lower surface are tightly adhered to the surface of the vacuum suction cup 1, ensuring the wafer surface flatness. Furthermore, by integrating both suction cup adsorption and air channel adsorption methods onto the vacuum suction cup 1 and air plate 3, the structure is compact and meets the requirements for installing the wafer adsorption device in confined spaces.

[0090] As a preferred implementation method, refer to Figure 10The vacuum nozzle 501 includes, along its length, an adsorption section, a deformation section, and a connecting section. The adsorption section is used to adsorb the wafer, and the deformation section is used to deform and shrink after the adsorption section adsorbs the wafer, so that the upper end of the adsorption section shrinks to be flush with the upper surface of the vacuum chuck 1. Specifically, before the vacuum nozzle 501 adsorbs the wafer, the top surface of the adsorption section of the vacuum nozzle 501 protrudes from the upper surface of the vacuum chuck 1. During vacuum adsorption, the adsorption section adsorbs the wafer. Because the vacuum nozzle 501 has a certain amount of deformation, the adsorption section retracts into the second through hole, thereby ensuring that the adsorption section of the vacuum nozzle 501 does not exceed the upper surface of the vacuum chuck 1. When the wafer reaches the bottom, it is completely attached to the upper surface of the vacuum chuck 1. Under the combined action of multiple sets of vacuum chucks 1, better flatness is achieved. The above structural design ensures, on the one hand, that the vacuum nozzle 501 can completely adsorb the wafer and fully adhere to the upper surface of the vacuum chuck 1, thereby ensuring the flatness of the wafer. On the other hand, there is no need to set up a lifting mechanism; the deformation of the deformation part can ensure that the adsorption part of the vacuum nozzle 501 can retract into the second through hole after adsorbing the wafer.

[0091] The connecting part is used to connect the air tube 502. The vacuum nozzle 501 protruding from the vacuum suction cup 1 can improve the wafer adsorption success rate when the wafer assembly 2 drives the wafer to descend. Both the adsorption part and the deformation part of the vacuum nozzle 501 are made of soft material, such as rubber, to prevent damage to the wafer. It also allows the vacuum nozzle 501 to still make complete contact with the wafer surface with poor flatness, so as not to produce air leakage, and to generate a pulling force on the wafer, so that even areas with large deformation can still be adsorbed and flattened.

[0092] In a preferred embodiment, the lower end of the vacuum nozzle 501 is connected to the air tube 502 via a buffer mechanism 11. The buffer mechanism 11 has a buffer stroke along the axial direction of the vacuum nozzle 501 so that the vacuum nozzle 501 can adapt to different warpages of the wafer.

[0093] Specifically, the buffer mechanism 11 includes a shaft core 111, a sleeve 112, and a spring 113. One end of the shaft core 111 is threadedly connected to the lower end of the vacuum nozzle 501, and the other end of the shaft core 111 is axially movably connected to one end of the air tube 502. The sleeve 112 is fitted onto the outer circumferential surface of the shaft core 111, forming a receiving space between the sleeve 112 and the outer circumferential surface of the shaft core 111. The spring 113 is fitted onto the outer circumferential surface of the shaft core 111 and located within this receiving space. The upper end of the spring 113 abuts against a boss on the outer circumferential surface of the shaft core 111, and the lower end of the spring 113 abuts against a boss on the inner circumferential surface of the sleeve 112. The end of the sleeve 112 near the air tube 502 can be connected to or abut against the air tube 502. Therefore, when the local warpage of the wafer is large, even if the deformation of the deformable part of the vacuum nozzle 501 reaches its maximum, it is insufficient to flatten the wafer. In this case, the vacuum nozzle 501 cooperates with the buffer mechanism 11. The vacuum nozzle 501 presses down on the shaft core 111, which compresses the spring 113. The buffer mechanism 11 generates a buffer stroke, allowing the vacuum nozzle 501 to have a larger travel distance, thereby flattening the wafer with larger warpage and adapting to the different warpages of the wafer. After the inspection is completed, when the vacuum nozzle 501 no longer holds the wafer, under the restoring force of the spring 113, the suction part of the vacuum nozzle 501 protrudes from the upper surface of the vacuum chuck 1. As an example, the buffer stroke of the buffer mechanism 11 can be 1-5mm, for example, 3mm.

[0094] In a preferred embodiment, a first vacuum connector (not shown) is connected to a plurality of first vacuum interfaces 503 via pipes. The pipes between the first vacuum connector and each first vacuum interface 503 are of the same length. Each first vacuum interface 503 is connected to the same plurality of gas pipes 502. The first adsorption gas channel 4 between each first vacuum interface 503 and each connected gas pipe 502 is of the same length. Each gas pipe 502 is of the same length, so that the length of the vacuum channel between the first vacuum connector and each vacuum nozzle 501 is the same, so that each vacuum nozzle 501 can simultaneously adsorb wafers. After the first vacuum connector is connected to the vacuum pump, the vacuum force reaches each vacuum nozzle 501 simultaneously, and the adsorption force of each vacuum nozzle 501 is the same, thereby further ensuring the uniformity of the adsorption force of the vacuum nozzle 501 on the wafer, which is beneficial to further improve the flatness of the wafer.

[0095] A vacuum pressure valve can be installed on the first vacuum connector to adjust the adsorption force of the vacuum nozzle 501, so that the adsorption force of each suction cup is the same. When adsorbing the wafer, the wafer will not be uneven due to excessive or insufficient local adsorption force, thus further improving the wafer flatness.

[0096] In a preferred embodiment, the second vacuum connector is connected to several second vacuum interfaces 504 via pipes, and the pipes between the second vacuum connector and each second vacuum interface 504 are of the same length. The second adsorption channel 6 is a straight channel, with one end connected to a second vacuum interface 504 and the other end connected to an annular vacuum channel 7 via a through hole 9 on the vacuum suction cup 1. The annular vacuum channel 7 is connected to several second vacuum interfaces 504 via several second adsorption channels 6. The through holes 9 between the annular vacuum channel 7 and the several second adsorption channels 6 are evenly spaced along the annular vacuum channel 7 so that the length of the vacuum channel between the second vacuum connector and several through holes 9 of the same annular vacuum channel 7 is the same, allowing each annular vacuum channel 7 to simultaneously adsorb wafers. After the second vacuum connector is connected to the vacuum pump, the vacuum force reaches each through hole 9 simultaneously, and the adsorption force of each annular vacuum channel 7 is the same or close, thereby further ensuring the uniformity of the adsorption force on wafers at various points in the annular vacuum channel 7, which is beneficial to further improving the flatness of the wafers.

[0097] Several second adsorption channels 6 corresponding to the same annular vacuum channel 7 are connected and located in the same thickness plane of the vacuum suction cup 1, while the second adsorption channels 6 corresponding to different annular vacuum channels 7 are connected and located in different thickness planes of the vacuum suction cup 1.

[0098] In use, external robotic arms or other wafer transfer devices transfer the wafer to the wafer adsorption device in this embodiment. The wafer attachment assembly 2 operates, adsorbing the wafer onto the lower surface of the wafer via the wafer attachment nozzle 201, transferring the wafer from the external transfer device to the wafer adsorption device. Subsequently, the wafer attachment nozzle 201 descends under the action of the lifting drive mechanism 202, bringing the wafer closer to the vacuum chuck 1. The adsorption assembly is activated. When the wafer descends into the adsorption range of the vacuum nozzle 501, the adsorption part of the vacuum nozzle 501 adsorbs the lower surface of the wafer. The wafer continues to descend until the lower surface of the wafer is in contact with the upper surface of the vacuum chuck 1. At this time, the deformable part of the vacuum nozzle 501 contracts, and the adsorption part and the upper surface of the vacuum chuck 1 are aligned. With the wafer surface flush, the wafer pick-up nozzle 201 is fully lowered into the first through hole. The top of the wafer pick-up nozzle 201 is flush with or below the upper surface of the vacuum chuck 1. At this time, both the annular vacuum channel 7 and the branch air channel 8 apply adsorption force to the lower surface of the wafer. The vacuum pick-up nozzle 501, the annular vacuum channel 7, and the branch air channel 8 cooperate with each other to make the lower surface of the wafer completely adhere to the upper surface of the vacuum chuck 1, thereby ensuring the overall flatness of the wafer. Subsequently, the moving platform 15 operates to move the wafer under the lens of the optomechanical assembly 13 and automatically adjusts the distance and relative angle between the wafer and the lens. The optomechanical assembly 13 operates to capture image information of the wafer and perform defect detection on the wafer.

[0099] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the invention without departing from the principles and spirit of the invention, and all such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A wafer inspection device, characterized in that, include: Wafer adsorption device (12), for receiving wafers, includes: Vacuum chuck (1) has a flat upper surface, used to flatten the wafer surface after it is attached to the chuck; A wafer receiving assembly (2) is provided, wherein a portion of the structure of the wafer receiving assembly (2) is elliptical and movably mounted on the vacuum chuck (1) for receiving wafers; An adsorption assembly is provided on the vacuum chuck (1) to adsorb the wafers received by the bonding assembly (2) so that the wafers are attached to the upper surface of the vacuum chuck (1). A vacuum plate (3) is provided below the vacuum suction cup (1) to provide a vacuum channel for at least a portion of the adsorption assembly. Optomechanical assembly (13) is used to be disposed above the wafer adsorption device (12) for detecting the wafer; Mounting base (14), the wafer adsorption device (12) is disposed on the mounting base (14), the mounting base (14) is used to fix the wafer adsorption device (12). The mobile platform (15) is provided with the mounting base (14) on the mobile platform (15), and the mobile platform (15) is used to adjust the spatial position and angle of the target wafer relative to the optomechanical assembly (13).

2. The wafer inspection equipment as described in claim 1, characterized in that, The mobile platform (15) includes: A rotating component is provided at the bottom of the mounting base (14) to drive the wafer adsorption device (12) to rotate in order to adjust the detection angle of the wafer relative to the optomechanical component (13); Z-axis moving component, which is disposed on the rotating component, for driving the wafer adsorption device (12) to move in the Z-axis direction; The Y-axis moving component is disposed on the Z-axis moving component and is used to drive the wafer adsorption device (12) to move in the Y-axis direction; An X-axis moving component is provided on the Y-axis moving component to drive the wafer adsorption device (12) to move in the X-axis direction; The X-axis, Y-axis and Z-axis are perpendicular to each other, and the Z-axis is parallel to the thickness direction of the vacuum chuck (1).

3. The wafer inspection equipment as described in claim 1, characterized in that, Several support columns (10) are provided between the vacuum suction cup (1) and the air plate (3). The optical-mechanical assembly (13) includes: a lens, a camera, and a light source; The wafer inspection equipment further includes a controller, which is communicatively connected to the wafer adsorption device (12), the optomechanical component (13), and the moving platform (15) to control the operation of the wafer adsorption device (12), the optomechanical component (13), and the moving platform (15) and to inspect the wafer.

4. The wafer inspection equipment as described in claim 3, characterized in that, The vacuum suction cup (1) is provided with several first through holes running vertically through it, and the connector assembly (2) includes: A plurality of splice nozzles (201), each of the splice nozzles (201) being vertically and vertically passing through a first through hole for descending after adsorbing and receiving a wafer so that the lower surface of the wafer approaches the upper surface of the vacuum chuck (1); A lifting drive mechanism (202) is used to connect each of the splice nozzles (201) and to drive the splice nozzles (201) to rise or fall so that the splice nozzles (201) extend out of or retract into the first through hole.

5. The wafer inspection equipment as described in claim 3, characterized in that, The vacuum suction cup (1) is provided with several second through holes running vertically through it, and the air plate (3) is provided with several first adsorption air channels (4). The adsorption assembly includes: A plurality of vacuum nozzles (501), each of the vacuum nozzles (501) being disposed in a second through hole, and the upper end of the vacuum nozzle (501) protruding from the upper surface of the vacuum chuck (1) for adsorbing wafers; A plurality of air tubes (502), each of the air tubes (502) being connected to the lower end of a vacuum nozzle (501), and the end of each air tube (502) away from the vacuum nozzle (501) being connected to a first adsorption air channel (4) on the air plate (3); A plurality of first vacuum ports (503) are provided on the air plate (3). Each first vacuum port (503) is used to connect one or more air pipes (502) through a first adsorption air channel (4) to provide a vacuum channel for the vacuum nozzle (501).

6. The wafer inspection equipment as described in claim 5, characterized in that, The plurality of vacuum nozzles (501) are divided into multiple groups along the radial direction of the vacuum suction cup (1). Each group of vacuum nozzles (501) includes multiple vacuum nozzles (501) located on the same circumference. The multiple vacuum nozzles (501) are distributed at intervals on the same circumference. The circumferences of the multiple groups of vacuum nozzles (501) are all concentric with the vacuum suction cup (1).

7. The wafer inspection equipment as described in claim 5, characterized in that, The vacuum nozzle (501) includes, along its length, an adsorption section, a deformable section, and a connecting section. The adsorption section is used to adsorb a wafer. The deformable section is used to deform and shrink after the adsorption section adsorbs the wafer, so that the upper end of the adsorption section shrinks to be flush with the upper surface of the vacuum chuck (1). The connecting section is used to connect to the air tube (502); and / or, The suction part and the deformable part of the vacuum nozzle (501) are both made of soft material; and / or, The lower end of the vacuum nozzle (501) is connected to the air tube (502) through a buffer mechanism (11). The buffer mechanism (11) has a buffer stroke along the axial direction of the vacuum nozzle (501) so that the vacuum nozzle (501) can adapt to different warpages of the wafer.

8. The wafer inspection equipment as described in claim 5, characterized in that, The wafer adsorption device (12) further includes a first vacuum connector, which is connected to the plurality of first vacuum interfaces (503) via a pipe. The pipe between the first vacuum connector and each first vacuum interface (503) has the same length. Each first vacuum interface (503) is connected to the same plurality of gas tubes (502). The first adsorption air passage (4) between each first vacuum interface (503) and each connected gas tube (502) has the same length. The length of each gas tube (502) is the same, so that the length of the vacuuming channel between the first vacuum connector and each vacuum nozzle (501) is the same.

9. A wafer inspection device as described in claim 3, characterized in that, The vacuum chuck (1) is provided with a plurality of second adsorption channels (6), and the upper surface of the vacuum chuck (1) is provided with a plurality of annular vacuum channels (7) concentric with the vacuum chuck (1). The annular vacuum channels (7) are used to adsorb wafers. The adsorption assembly further includes: A plurality of second vacuum ports (504) are disposed on the vacuum suction cup (1), each second vacuum port (504) being used to connect one or more annular vacuum channels (7) through a second adsorption channel (6).

10. A wafer inspection device as described in claim 9, characterized in that, The upper surface of the vacuum suction cup (1) is also provided with several branch air channels (8), which are evenly distributed on the several annular vacuum channels (7). The plurality of annular vacuum channels (7) are not interconnected, or adjacent plurality of annular vacuum channels (7) are connected by branch channels (8); and / or, The wafer adsorption device (12) further includes a second vacuum connector, which is connected to the plurality of second vacuum interfaces (504) through a pipe. The pipe between the second vacuum connector and each second vacuum interface (504) has the same length. The second adsorption gas channel (6) is a straight gas channel. One end of the second adsorption gas channel (6) is connected to a second vacuum interface (504). The other end of the second adsorption gas channel (6) is connected to an annular vacuum channel (7) through a through hole (9) on the vacuum chuck (1). The annular vacuum channel (7) is connected to a plurality of second vacuum interfaces (504) through a plurality of second adsorption gas channels (6). The through holes (9) between the annular vacuum channel (7) and the plurality of second adsorption gas channels (6) are evenly spaced along the annular vacuum channel (7) so that the length of the vacuum channel between the second vacuum connector and a plurality of through holes (9) of the same annular vacuum channel (7) is the same. The same annular vacuum channel (7) is connected to several corresponding second adsorption channels (6) and is located in the same thickness plane of the vacuum suction cup (1). Different annular vacuum channels (7) are connected to corresponding second adsorption channels (6) and are located in different thickness planes of the vacuum suction cup (1).

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