Wafer fixing device and detection equipment

Abstract

The application relates to the technical field of wafer production, in particular to a wafer fixing device and detection equipment, which comprises a bearing table, a wafer, a stabilizing assembly and a power assembly; the stabilizing assembly is fixedly installed on the bearing table, and the wafer is placed on the stabilizing assembly; the power assembly is fixedly installed in the bearing table; the detection equipment comprises a metal sheet, a contact, a visual sensor and a control unit; the application solves the problem that, in the process of cleaning the wafer by the existing wafer fixing device, the wafer is easily slid downward due to the pressure of the spray flushing, the wafer cannot be kept horizontal during the sliding process, and the wafer is easily inclined; and the wafer cannot slide and incline during the cleaning of the wafer.

Description

Technical Field

[0001] This invention relates to the field of wafer manufacturing technology, specifically to a wafer fixing device and testing equipment. Background Technology

[0002] In the wafer manufacturing process, after the wafer cleaning stage, vision inspection equipment is used to check the cleaning status of the wafers to prevent residual contaminants from affecting subsequent processing. During cleaning, the wafers are held and fixed on a support platform by multiple evenly spaced posts. The support platform drives the wafers to rotate at high speed, and chemicals are sprayed downwards from above to clean them. After cleaning, the inspection equipment uses a vision sensor to inspect the wafer surface. Since the vision sensor takes pictures when the wafer sample is placed horizontally, the wafers usually need to be kept horizontal after cleaning to obtain more accurate inspection results. If the wafer is tilted, its vertical projection will change from a circle to an ellipse, affecting the inspection. At the same time, a tilted wafer will also reflect light sources around the vision sensor, causing glare interference.

[0003] When cleaning the front side of a wafer, commonly used cleaning equipment incorporates stepped supports to prevent the wafer from sliding downwards during the spraying process. However, when cleaning the back side of the wafer, only the back side typically needs to contact the chemical cleaning solution, while the front chip structure should not come into contact with the chemicals or hard surfaces. Therefore, the fixing posts used are cylindrical posts without steps. During the cleaning process, due to the pressure of the spray, the wafer is prone to sliding downwards. During this downward movement, the wafer cannot remain level and tends to tilt, affecting inspection. Current solutions to this problem involve increasing the clamping force of the fixing posts and increasing the friction between the fixing posts and the wafer, but these methods do not effectively solve the problem of wafer sliding and tilting during cleaning.

[0004] To address this, a wafer fixing device and testing equipment are proposed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that in the process of cleaning wafers, the existing wafer fixing device is prone to sliding downwards due to the pressure of the spray rinsing. During the downward sliding process, the wafer cannot keep horizontal and is prone to tilting, which affects the accuracy of the test results.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a wafer fixing device, comprising a support stage, a wafer, a stabilizing component, and a power component; the stabilizing component is fixedly installed on the support stage, and the wafer is placed on the stabilizing component; the stabilizing component, through radial movement, restricts the radial displacement and axial tilt of the wafer, thereby stabilizing the wafer; the power component is fixedly installed inside the support stage, and the power component, through pneumatic drive, moves the stabilizing component radially to clamp and fix the wafer.

[0007] To ensure the wafer remains level during the cleaning process, a stabilizing assembly is used to fix the wafer on the support platform. The stabilizing assembly is controlled by a power component to maintain the wafer's position, preventing it from sliding or tilting. During processing, the wafer edges are chamfered to prevent edge breakage and damage from thermal stress. This also increases the flatness of the epitaxial layer and photoresist at the wafer edges. The main function of the stabilizing assembly is to provide auxiliary support to the chamfered edges of the wafer, preventing it from falling. It also uses components to contact the chamfered edges to prevent excessive tilting and warping, thus avoiding misjudgments in visual inspection results due to wafer tilt.

[0008] The stabilizing assembly includes a fixed post, an upper sleeve, a lower sleeve, an upper pressure block, a lower pressure block, a pressure spring, and a compression spring. The upper sleeve is movably mounted on the top of the fixed post, and the lower sleeve is movably mounted on the bottom of the fixed post. The upper pressure block is slidably mounted on the bottom of the upper sleeve, and the lower pressure block is slidably mounted on the top of the lower sleeve. A pressure spring is engaged at the top of the upper pressure block, and the pressure spring is engaged between the upper sleeve and the upper pressure block, with the pressure spring located outside the fixed post. A compression spring is engaged at the bottom of the lower pressure block, and the compression spring is located between the lower sleeve and the lower pressure block, with the compression spring located outside the fixed post.

[0009] During the wafer cleaning process, the wafer rotates at high speed on the fixed post. The upper and lower sleeves stabilize the wafer. Since the upper and lower sleeves are movable relative to the upper and lower pressure blocks respectively, and pressure springs and compression springs are installed between the upper sleeve and the upper pressure block, and between the lower sleeve and the lower pressure block, the wafer is not rigidly blocked during its descent. The pressure springs and compression springs provide a buffering and stress-relieving effect for the wafer, preventing excessive external force on the chamfered edges of the wafer and thus avoiding damage. At the same time, the lower pressure block on the lower sleeve can serve as a reference for the wafer's positioning. When the back side of the wafer is cleaned and placed manually, the wafer is prone to tilting because there is no stepped structure on the fixed post. This tilting is exacerbated during high-speed rotation cleaning. With the lower pressure block on the lower sleeve as a reference position, the problem of wafer tilting during manual placement can be significantly reduced.

[0010] The axis of the fixing column is provided with a cross-section, and the width of the cross-section is 2 / 3 of the diameter of the fixing column. The cross-section of the fixing column is provided with a scale bar, and the bottom of the fixing column is provided with a circular boss. A metal tube is provided inside the center of the fixing column, and the length of the metal tube is equal to the length of the fixing column.

[0011] During operation, the upper and lower sleeves rotate at high speed along with the wafer. To ensure their stability, a cross-section is provided along the axis of the fixing column. This cross-section engages with the upper and lower sleeves to prevent rotation. The width of the cross-section is 2 / 3 of the diameter of the fixing column. This further enhances the stability of the upper and lower sleeves and facilitates the installation of pressure and compression springs. If the cross-section width is too large, pressure and compression springs cannot be installed. During installation, it is necessary to ensure that all components on each fixing column are at the same height. A reference structure can be set to keep all lower sleeves at the same horizontal height. Therefore, a circular boss is provided at the bottom of the fixing column as the installation reference for the lower sleeves to ensure they are at the same horizontal height. Scale strips are provided on the cross-section of the fixing column. Since the upper sleeve is located above the wafer, its height can be adjusted according to the wafer thickness, thereby adjusting the height of the upper pressure block to meet the cleaning requirements of thicker wafers. The graduations on the cut surface allow operators to more accurately position the height of the upper sleeve, ensuring that each upper sleeve is installed at the same height and guaranteeing the detection accuracy of the metal plate and contact points. Simultaneously, to increase the stability of the upper sleeve, a metal tube is installed inside the center of the fixing post. Since numerous parts need to be installed on the fixing post, its strength needs to be increased by adding a metal tube at its center. Additionally, the metal tube can house and store electrical wires.

[0012] The upper sleeve is provided with a roller on the top outer side and an arc-shaped block is provided inside the upper sleeve. The length of the arc-shaped block is equal to the length of the upper sleeve and the arc-shaped block cooperates with the tangent on the fixed column. The lower sleeve is provided with an arc-shaped block inside. The length of the arc-shaped block is equal to the length of the lower sleeve and the arc-shaped block cooperates with the tangent on the fixed column.

[0013] When adjusting the height of the upper sleeve, first turn the upper knob to loosen it, and then move it up and down. Directly moving the upper sleeve makes precise positioning difficult, and the upper sleeve may shift when the upper knob is tightened. By installing rollers on the upper sleeve, the contact between the rollers and the cut surface increases friction between the upper sleeve and the fixing post, reducing the probability of the upper sleeve shifting when tightening the bolts. Simultaneously, adjusting the height of the upper sleeve can be controlled by rolling the rollers, allowing for more precise adjustment and positioning, and making it easier for operators to position all upper sleeves at the same height. The arc-shaped blocks inside the upper and lower sleeves are designed to cooperate with the cut surface on the fixing post to prevent rotation and ensure stability. The lengths of the arc-shaped blocks equal to the lengths of the upper and lower sleeves further enhance the stability of the upper and lower sleeves on the fixing post, preventing rotation during wafer cleaning, which could cause the wafer to slide or tilt.

[0014] The upper sleeve has a circular hole, and an upper knob is rotatably installed inside the circular hole. The upper knob is located below the roller. The diameter of the circular hole is 1 / 2 of the width of the cross section of the fixed column. The lower sleeve has a circular hole, and a lower knob is rotatably installed inside the circular hole. The diameter of the circular hole is 1 / 2 of the width of the cross section of the fixed column.

[0015] When cleaning wafers, the wafers need to be placed on a fixing post and secured by an upper and lower sleeve. Since both the upper and lower sleeves can slide on the fixing post, they need to be adjusted and fixed using an upper knob on the upper sleeve and a lower knob on the lower sleeve. The distance between the upper and lower sleeves is adjusted according to the thickness of the wafer to make the wafer more stable and prevent it from sliding or tilting during subsequent testing. The round and circular holes are used to install the upper and lower knobs. The diameter of the round hole is half the width of the cross-section of the fixing post, and the diameter of the circular hole is half the width of the cross-section of the fixing post. This ensures that the inner ends of the upper and lower knobs can fully contact the cross-section of the fixing post to increase the friction between them, thereby further improving the stability of the upper and lower sleeves.

[0016] The bottom of the upper pressure block and the top of the lower pressure block are respectively provided with conical inclined surfaces. An annular groove is provided on the conical inclined surface. The included angle between the axis of the annular groove and the axis of the lower pressure block is 10°-15°, and the part of the annular groove away from the wafer is lower than the part in contact with the wafer.

[0017] When a wafer rotates at high speed, it may fall downwards due to the clamping force being less than the spray pressure. The conical inclined surface provides support for the wafer, slowing down or preventing it from falling further. During the cleaning process, chemicals will adhere to the upper sleeve, lower sleeve, upper pressure block, and lower pressure block. Therefore, appropriate structures should be designed to facilitate the downward flow of chemicals from the components, while keeping them away from the wafer. Inclined annular grooves are provided on the upper and lower pressure blocks, and the contact surfaces of the upper and lower pressure blocks are also inclined, with the inclined surfaces all tilted downwards away from the wafer. During the wafer's rotation, the chemicals are affected by centripetal force and diffuse away from the wafer. In this process, some chemicals are blocked by the upper and lower pressure blocks and adhere to them. With the inclined surfaces, the chemicals are guided outwards by the annular grooves, preventing the accumulation of chemicals on the annular grooves. Considering that the guiding effect of the annular groove is not obvious when the angle is less than 10°, and the processing of the annular groove is difficult when the angle is greater than 15°, the tilt angle is set between 10° and 15°.

[0018] The power assembly includes an air pump, an air pipe, and a telescopic tube. The air pump is fixedly installed inside the support platform. One end of the air pipe is fixedly installed on the air pump, and the other end of the air pipe is fixedly installed on one end of the telescopic tube. The other end of the telescopic tube is fixedly installed on the bottom side of the fixed column. The telescopic length of the telescopic tube is equal to the moving distance of the fixed column.

[0019] To ensure the clamping posts can securely hold the wafers, a high air pressure is generated by an air pump inside the power unit. This air pressure causes the telescopic tubes to extend and retract, thus moving the clamping posts. To ensure that each clamping post experiences the same tension, different air pipes must be connected to the telescopic tubes, allowing the tubes to move simultaneously. This ensures that all clamping posts move at the same time, clamping the wafers securely. The extension length of the telescopic tube is equal to the movement distance of the clamping post, ensuring that the telescopic tube has a certain displacement, making it suitable for clamping wafers of different sizes.

[0020] The support platform has a rectangular groove inside, and a circular groove is formed at the center of the four sides of the rectangular groove. Four arc-shaped through holes are formed radially at the center of the top of the support platform. The arc-shaped through holes are located above the circular grooves and are interconnected with the circular grooves. The length of the arc-shaped through holes is equal to the length of the circular grooves, and the length of the arc-shaped through holes is 3 / 4 of the diameter of the support platform.

[0021] The support platform is used to support the entire stabilization assembly, power assembly, and wafers. To ensure the wafers are fixed, the power assembly inside the support platform drives the stabilization assembly. The rectangular groove inside the support platform is for installing pneumatic components, and the circular grooves around the rectangular groove are for installing telescopic tubes. The telescopic tubes can extend and retract within the circular grooves, moving the fixing posts and thus fixing the wafers. The length of the arc-shaped through hole is equal to the length of the circular groove to ensure sufficient displacement of the fixing posts. The length of the arc-shaped through hole is 3 / 4 of the diameter of the support platform. While ensuring sufficient displacement of the fixing posts, it can also be adjusted according to the size of different wafers.

[0022] An inspection device includes a metal sheet, contacts, a vision sensor, and a control unit. The metal sheet is fixedly installed on the bottom inner wall of an upper sleeve and the top inner wall of a lower sleeve. The contacts are fixedly installed on the top outer side of an upper pressure block and the bottom outer side of a lower pressure block, with the contacts located on the line connecting the center of the upper and lower pressure blocks to the center of the wafer. The metal sheet and the contacts are connected by wires, with the wires located inside a metal tube. The vision sensor is fixedly installed above the wafer.

[0023] The system detects whether the wafer has slipped or tilted by contacting the upper and lower pressure blocks when it tilts, squeezing either block to cause it to contract and move. When the upper and lower pressure blocks are not subjected to external force, the metal plates are in contact with the contacts, forming a circuit. When the upper and lower pressure blocks are subjected to external force from the wafer and thus contract and move, the contacts move away from the metal plates, causing the circuit to break. After the circuit breaks, the control unit receives the break signal and determines whether the wafer has slipped or tilted based on the number and combination of break signals. When all the circuit signals in multiple sets of upper and lower sleeves, as well as upper and lower pressure blocks, are open circuits, it can be determined that the wafer has slid down. When the circuit signals in a certain upper and lower sleeve, as well as upper and lower pressure blocks, are open circuits, and the circuit signals formed by the lower sleeve and lower pressure block opposite to that upper sleeve are also open circuits, it can be determined that the wafer has tilted. The control unit then alarms and records the judgment result, and then feeds it back to the operator. When a batch tilting problem occurs, the operator can choose to randomly inspect the wafers and re-perform visual inspection. At the same time, the equipment should be repaired and adjusted in a timely manner to prevent the wafers from tilting again and affecting the visual inspection, thus fully ensuring the accuracy of visual inspection.

[0024] Ideally, when the lower pressure block is subjected to external force from the wafer, it will move downwards as a whole, and the contact can smoothly detach from the metal sheet. However, since the upper and lower pressure blocks are fitted onto the fixed post and need to slide relative to the fixed post, there is a gap between the upper and lower pressure blocks and the fixed post. At the same time, when the wafer diameter is smaller, the range of motion of the wafer on both sides after tilting is smaller, which may not be enough to completely detach the plane where the contact is located from the metal sheet. This may result in the contact remaining in contact with the metal sheet even after the wafer tilts and presses down on the upper and lower pressure blocks. Therefore, the contact is set on the side closer to the wafer. The center of the wafer is connected to the center of the upper and lower pressure blocks, and the contact is located on the line closer to the wafer. This reduces the possibility of detection errors due to the contact position setting and improves detection sensitivity.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention, by setting a stabilizing component and a power component on the support platform, restricts the axial and radial displacement of the wafer through the cooperation of the stabilizing component and the power component. This allows the wafer to be supported without contacting the front chip of the wafer during cleaning, preventing the wafer from sliding down when cleaning the back. This prevents the wafer from sliding down or tilting during cleaning, improving the cleaning effect and also improving the accuracy of visual inspection.

[0026] 2. This invention, by setting a stabilizing component and a power component on the support platform, and through the cooperation of the detection equipment and the stabilizing component, enables the wafer to be restricted and fixed during the cleaning process by the stabilizing component, while the detection equipment can detect the wafer and, based on the stress on the wafer, cause the circuit to be broken. Based on the number and combination of the broken circuit signals, it can be determined whether the wafer has slipped or tilted, thus achieving the function of real-time monitoring of the wafer rotation.

[0027] 3. The present invention provides a power component and a stabilizing component on the support platform. Through the cooperation between the power component and the stabilizing component, the power component drives the fixing column to move radially via pneumatics and fixes the wafer. This ensures that the wafer is subjected to the same force on all four sides, thereby improving the cleaning effect of the wafer and the accuracy of subsequent visual inspection. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 Enlarged schematic diagram of part A; Figure 3 This is a schematic diagram of the overall structure of the present invention; Figure 4 for Figure 3 Enlarged schematic diagram of part B; Figure 5 for Figure 4 Enlarged schematic diagram of part C; Figure 6 This is a schematic diagram of the lower sleeve and lower pressure block of the present invention; Figure 7 for Figure 6 Enlarged schematic diagram of part D; Figure 8 This is a top view of the present invention; Figure 9 This is a schematic diagram of the contact point positions according to the present invention; Figure 10 This is a schematic diagram of the inclination angle of the annular groove of the present invention; Figure 11 This is a cross-sectional view of the lower sleeve of the present invention; Figure 12 This is a cross-sectional view of the upper sleeve of the present invention; Figure 13 This is a cross-sectional view of the support platform of the present invention.

[0029] In the diagram: 1. Support platform; 11. Rectangular groove; 12. Circular groove; 13. Arc-shaped through hole; 2. Wafer; 3. Stabilizing component; 31. Fixing post; 311. Facet; 312. Scale bar; 313. Circular boss; 314. Metal tube; 32. Upper sleeve; 321. Roller; 322. Arc-shaped block; 323. Circular hole; 324. Upper knob; 33. Lower sleeve; 331. Arc block; 332. Circular hole; 333. Lower knob; 34. Upper pressure block; 35. Lower pressure block; 36. Pressure spring; 37. Compression spring; 4. Power component; 41. Air pump; 42. Air pipe; 43. Telescopic pipe; 5. Conical inclined surface; 6. Annular groove; 7. Metal sheet; 8. Contact point. Detailed Implementation

[0030] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0031] like Figure 1 and Figure 13As shown, the present invention provides a wafer fixing device and a testing device, the technical solution of which is as follows: A wafer fixing device includes a support platform 1, a wafer 2, a stabilizing component 3, and a power component 4; the stabilizing component 3 is fixedly installed on the support platform 1, and the wafer 2 is placed on the stabilizing component 3. The stabilizing component 3 restricts the radial displacement and axial tilt of the wafer 2 by radial movement, thereby stabilizing the wafer 2; the power component 4 is fixedly installed inside the support platform 1, and the power component 4 drives the stabilizing component 3 to move radially by pneumatic drive, thereby clamping and fixing the wafer 2.

[0032] When cleaning wafer 2, wafer 2 is first placed on top of stabilizing component 3 on carrier stage 1. Then, power component 4 is activated, which transmits power to stabilizing component 3, causing stabilizing component 3 to move radially. This fixes wafer 2 on top of stabilizing component 3, restricting the radial and axial movement of wafer 2. This ensures that wafer 2 will not slide or tilt during the cleaning process, greatly improving the cleaning efficiency of wafer 2 and also improving the accuracy of subsequent visual inspection.

[0033] like Figures 2 to 12 As shown, the stabilizing component 3 includes a fixed post 31, an upper sleeve 32, a lower sleeve 33, an upper pressure block 34, a lower pressure block 35, a pressure spring 36, and a compression spring 37. The upper sleeve 32 is movably installed on the top of the fixed post 31, and the lower sleeve 33 is movably installed on the bottom of the fixed post 31. The upper pressure block 34 is slidably installed on the bottom of the upper sleeve 32, and the lower pressure block 35 is slidably installed on the top of the lower sleeve 33. The pressure spring 36 is engaged with the top of the upper pressure block 34, and the pressure spring 36 is engaged between the upper sleeve 32 and the upper pressure block 34, and the pressure spring 36 is located outside the fixed post 31. The compression spring 37 is engaged with the bottom of the lower pressure block 35, and the compression spring 37 is engaged between the lower sleeve 33 and the lower pressure block 35, and the compression spring 37 is located outside the fixed post 31.

[0034] When fixing wafer 2, wafer 2 first needs to be placed on fixing post 31, and the conical inclined surface 5 on the lower pressure block 35 on fixing post 31 is used as a reference to place wafer 2 horizontally. After wafer 2 is placed, since it is the first time to use it, the height of upper sleeve 32 needs to be adjusted. After adjusting upper sleeve 32 to a suitable height, upper sleeve 32 drives upper pressure block 34 to slide downward on fixing post 31. After upper pressure block 34 contacts the edge of wafer 2, upper sleeve 32 will not move, thus fixing upper sleeve 32 on fixing post 31. At the same time, fixing post 31 will move radially inward to radially clamp wafer 2, thereby limiting the radial and axial displacement of wafer 2 and preventing wafer 2 from sliding downward or tilting during the cleaning process.

[0035] like Figures 2 to 12 As shown, the axis of the fixing post 31 is provided with a cross-section 311, and the width of the cross-section 311 is 2 / 3 of the diameter of the fixing post 31. A scale bar 312 is provided on the cross-section 311 of the fixing post 31. A circular boss 313 is provided at the bottom of the fixing post 31. A metal tube 314 is provided inside the center of the fixing post 31. The length of the metal tube 314 is equal to the length of the fixing post 31.

[0036] During the cleaning process of wafer 2, wafer 2 is first placed on the fixing post 31 manually, and the height of the upper sleeve 32 is manually adjusted according to the scale strip 312 on the fixing post 31. The metal tube 314 is used to strengthen the support strength of the fixing post 31.

[0037] like Figure 2 , Figure 3 , Figure 4 , Figure 9 , Figure 10 , Figure 11 and Figure 12 As shown, a roller 321 is provided on the outer top of the upper sleeve 32, and an arc-shaped block 322 is provided inside the upper sleeve 32. The length of the arc-shaped block 322 is equal to the length of the upper sleeve 32, and the arc-shaped block 322 cooperates with the tangent surface 311 on the fixed post 31. An arc-shaped block 331 is provided inside the lower sleeve 33. The length of the arc-shaped block 331 is equal to the length of the lower sleeve 33, and the arc-shaped block 331 cooperates with the tangent surface 311 on the fixed post 31.

[0038] When adjusting the height of the upper sleeve 32, the roller 321 is manually rotated. The roller 321 will rotate on the tangent surface 311 of the fixed column 31, thereby driving the upper sleeve 32 to slide up and down on the fixed column 31, and adjusting the upper sleeve 32 to a suitable height.

[0039] like Figure 2 , Figure 3 , Figure 4 , Figure 6 , Figure 8 , Figure 9 , Figure 10 , Figure 11 and Figure 12 As shown, the upper sleeve 32 has a circular hole 323, and an upper knob 324 is rotatably installed inside the circular hole 323. The upper knob 324 is located below the roller 321. The diameter of the circular hole 323 is half the width of the upper cross section 311 of the fixed column 31. The lower sleeve 33 has a circular hole 332, and a lower knob 333 is rotatably installed inside the circular hole 332. The diameter of the circular hole 332 is half the width of the upper cross section 311 of the fixed column 31.

[0040] When adjusting the upper sleeve 32 and the lower sleeve 33, it is necessary to rotate the upper knob 324 and the lower knob 333 on the upper sleeve 32 and the lower sleeve 33 to move the upper knob 324 and the lower knob 333 radially inward, so that they come into contact with the cut surface 311 of the fixing post 31, thereby applying pressure to the cut surface 311 of the fixing post 31, and thus fixing the upper sleeve 32 and the lower sleeve 33 on the fixing post 31.

[0041] like Figure 2 , Figure 3 , Figure 4 , Figure 6 , Figure 8 , Figure 9 and Figure 10 As shown, the bottom of the upper pressure block 34 and the top of the lower pressure block 35 are respectively provided with conical inclined surfaces 5. An annular groove 6 is provided on the conical inclined surface 5. The angle between the axis of the annular groove 6 and the axis of the lower pressure block 35 is 10°-15°, and the part of the annular groove 6 away from the wafer 2 is lower than the part in contact with the wafer 2.

[0042] When cleaning wafer 2, wafer 2 is first placed horizontally on the fixing post 31, and the chamfer on the edge of wafer 2 will contact the conical inclined surface 5 to ensure that wafer 2 is on a horizontal surface. During the cleaning process, the cleaning liquid will flow downward along the annular groove 6. The liquid flows from the part of the annular groove 6 that contacts wafer 2 to the part of the annular groove 6 that is away from wafer 2, thereby preventing the cleaning liquid from accumulating on the annular groove 6.

[0043] like Figure 13As shown, the power assembly 4 includes an air pump 41, an air pipe 42, and a telescopic pipe 43. The air pump 41 is fixedly installed inside the support platform 1. One end of the air pipe 42 is fixedly installed on the air pump 41, and the other end of the air pipe 42 is fixedly installed on one end of the telescopic pipe 43. The other end of the telescopic pipe 43 is fixedly installed on the bottom side of the fixed column 31. The telescopic length of the telescopic pipe 43 is equal to the moving distance of the fixed column 31.

[0044] When fixing the wafer 2, the air pump 41 on the power assembly 4 is started, and gas is filled into the air pipe 42. The gas inside the air pipe 42 will flow into the four telescopic pipes 43. When the air pressure inside the telescopic pipe 43 increases, the telescopic pipe 43 will extend, thereby driving the fixing post 31 to move radially outward. When the air pressure inside the telescopic pipe 43 decreases, it will drive the fixing post 31 to move radially inward, thereby clamping and fixing the wafer 2 on the fixing post 31, so that the wafer 2 will not move radially, thus preventing the wafer 2 from radially displaced due to excessive pressure during the cleaning process.

[0045] like Figure 2 , Figure 3 and Figure 13 As shown, a rectangular groove 11 is provided inside the support platform 1, and a circular groove 12 is provided at the center of the four sides of the rectangular groove 11. Four arc-shaped through holes 13 are provided radially through the center of the top of the support platform 1. The arc-shaped through holes 13 are located above the circular grooves 12 and are interconnected with the circular grooves 12. The length of the arc-shaped through holes 13 is equal to the length of the circular grooves 12, and the length of the arc-shaped through holes 13 is 3 / 4 of the diameter of the support platform 1.

[0046] When cleaning the wafer 2, the wafer 2 needs to be fixed on the support platform 1 by the cooperation of the power component 4 and the stabilizing component 3. Then, the telescopic tube 43 on the power component 4 slides in the circular groove 12 on the support platform 1, thereby driving the stabilizing component 3 to move radially and clamp and fix the wafer 2.

[0047] like Figure 5 , Figure 7 and Figure 9 As shown, a detection device includes a metal sheet 7, a contact 8, a vision sensor, and a control unit. The metal sheet 7 is fixedly installed on the bottom inner wall of the upper sleeve 32 and the top inner wall of the lower sleeve 33. The contact 8 is fixedly installed on the top outer side of the upper pressure block 34 and the bottom outer side of the lower pressure block 35, and the contact 8 is located on the line connecting the center of the upper pressure block 34 and the lower pressure block 35 with the center of the wafer 2. The metal sheet 7 and the contact 8 are connected by wires, and the wires are located inside the metal tube 314. The vision sensor is fixedly installed above the wafer 2.

[0048] When placing wafer 2 manually, the lower pressure block 35 must not be squeezed during the placement process, otherwise it will cause misjudgment of the detection of metal sheet 7 and contact 8. After placement, if the electrical signal formed by metal sheet 7 and contact 8 breaks during the rotation of the support platform 1, the rotation status of wafer 2 can be determined based on the status of each group of electrical signals. Based on the number and combination of the broken signals, it can be determined whether wafer 2 has slid down or tilted.

[0049] In the overall working process, when this invention is first used to clean the back side of the wafer 2, the operator fixes the wafer 2 above the support platform 1 using the fixing post 31. When placing it, the conical inclined surface 5 of the lower pressure block 35 can be used as a reference to keep the wafer 2 horizontal. However, during this process, the lower pressure block 35 should not be squeezed, otherwise it will cause misjudgment of the detection between the metal sheet 7 and the contact point 8. After the wafer 2 is fixed, since it is the first time to use it, the height of the upper sleeve 32 needs to be adjusted. The upper sleeve 32 is connected to the fixing post 31 through the upper knob 324. When adjusting, turn the upper knob 324 to loosen the upper sleeve 32. Then, by turning the roller 321 set on the upper sleeve 32, the upper sleeve 32 is adjusted to a suitable height. Then, the upper knob 324 is tightened. Since each fixing post 31 is equipped with an upper sleeve 32, the height of the upper sleeve 32 needs to be adjusted sequentially by the scale strip 312 on the upper cut surface 311 of the fixing post 31. In addition, since both the upper sleeve 32 and the lower sleeve 33 need to rotate together with the wafer 2, a cross-section 311 is provided on the fixing post 31 to ensure the stability of the upper sleeve 32 and the lower sleeve 33. At the same time, the upper sleeve 32 and the lower sleeve 33 can slide on the cross-section 311 of the fixing post 31, avoiding the rotation of the upper sleeve 32 and the lower sleeve 33. Moreover, according to the scale on the cross-section 311 of the fixing post 31, when adjusting the height of the upper sleeve 32, the position of the scale of other upper sleeves 32 can be compared at the same time to ensure that each upper sleeve 32 is set at the same height.

[0050] When placing wafer 2, the fixing post 31 is driven by the air pump 41 on the power assembly 4. The air pump 41 fills the air pipe 42 with air, which flows into the telescopic tube 43. Due to the increased air pressure inside the telescopic tube 43, the telescopic tube 43 extends, and the telescopic tube 43 moves the fixing post 31 radially outward. When the air pump 41 extracts air from the air pipe 42, the air pressure inside the telescopic tube 43 decreases, causing the telescopic tube 43 to contract, and thus moving the fixing post 31. The column 31 moves radially inward to clamp and fix the wafer 2 on the fixing column 31. Therefore, when installing the upper sleeve 32, a clearance distance must be left for the wafer 2 to prevent the wafer 2 from getting stuck on the conical inclined surface 5 of the lower pressure block 35 when the fixing column 31 retracts. The clearance distance can be determined according to the actual working conditions, but it should not exceed 1mm, otherwise it will affect the detection results of the metal sheet 7 and the contact 8. Theoretically, the smaller the clearance distance, the higher the detection accuracy, but more accurate operation is also required when placing the wafer 2. If cleaning a thin wafer 2, and it is difficult to control the horizontal state of the wafer 2 when placing it, an auxiliary fixture should be designed to place the wafer 2. The fixture is placed on the support table 1, and the top surface of the fixture is at the same height as the lower pressure block 35. After the operator places the wafer 2 on the fixture, the fixing column 31 retracts towards the center to clamp the wafer 2, and then the fixture is pulled out from the side. Then the support table 1 is started again to clean the wafer 2.

[0051] When the support platform 1 rotates, if the electrical signal formed by the metal sheet 7 and contact 8 mentioned above is broken, the rotation status of the wafer 2 can be determined based on the status of each set of electrical signals. The number and combination of broken signals can be used to determine whether the wafer 2 has slid down or tilted. When all the circuit signals in multiple sets of upper sleeves 32 and lower sleeves 33 and upper pressure blocks 34 and lower pressure blocks 35 are open circuits, it can be determined that the wafer 2 has slid down. When the circuit signals in a certain upper sleeve 32 and lower sleeve 33 and upper pressure blocks 34 and lower pressure blocks 35 are open circuits, and the circuit signals formed by the lower sleeve 33 and lower pressure blocks 35 opposite to that upper sleeve 32 are also open circuits, it can be determined that the wafer 2 has tilted. The control unit then alarms and records the judgment result, and then feeds it back to the operator. When a batch tilting problem occurs, the operator can choose to randomly inspect the wafer 2 and re-perform visual inspection. At the same time, the equipment should be repaired and adjusted in time to avoid the wafer 2 tilting again and affecting the visual inspection, so as to fully ensure the accuracy of visual inspection.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wafer fixing device, comprising a support stage (1), a wafer (2), a stabilizing assembly (3), and a power assembly (4); characterized in that: A stabilizing component (3) is installed on the support platform (1). The stabilizing component (3) includes a fixing column (31). Four arc-shaped through holes (13) are radially opened at the top of the support platform (1) through the center position. The fixing column (31) passes through the arc-shaped through holes (13) and can move relative to the support platform (1) along the arc-shaped through holes (13). A wafer (2) is placed on the stabilizing component (3). The stabilizing component (3) restricts the radial displacement and axial tilt of the wafer (2) and stabilizes the wafer (2). A power component (4) is fixedly installed inside the support platform (1). The power component (4) drives the fixing column (31) to move radially through pneumatic means to clamp and fix the wafer (2). The stabilizing component (3) includes a fixed column (31), an upper sleeve (32), a lower sleeve (33), an upper pressure block (34), a lower pressure block (35), a pressure spring (36), and a compression spring (37); the axis of the fixed column (31) is provided with a cross-section (311); the upper sleeve (32) is movably installed on the top of the fixed column (31), the lower sleeve (33) is movably installed on the bottom of the fixed column (31), the upper pressure block (34) is slidably installed on the bottom of the upper sleeve (32), and the lower pressure block (35) is slidably installed on the bottom of the upper sleeve (32). 35) Slidingly installed on the top of the lower sleeve (33), the top of the upper pressure block (34) is fitted with a pressure spring (36), the pressure spring (36) is fitted between the upper sleeve (32) and the upper pressure block (34), and the pressure spring (36) is located outside the fixed post (31). The bottom of the lower pressure block (35) is fixedly installed with a compression spring (37), and the compression spring (37) is fitted between the lower sleeve (33) and the lower pressure block (35), and the compression spring (37) is located outside the fixed post (31). The upper sleeve (32) is provided with a roller (321) on the top outer side, and an arc-shaped block (322) is provided inside the upper sleeve (32). The length of the arc-shaped block (322) is equal to the length of the upper sleeve (32), and the arc-shaped block (322) cooperates with the cut surface (311) on the fixed column (31). The lower sleeve (33) is provided with an arc-shaped block (331) inside, and the length of the arc-shaped block (331) is equal to the length of the lower sleeve (33). The arc-shaped block (331) cooperates with the cut surface (311) on the fixed column (31). The upper sleeve (32) has a circular hole (323), and an upper knob (324) is rotatably installed inside the circular hole (323). The upper knob (324) is located below the roller (321). The diameter of the circular hole (323) is 1 / 2 of the width of the upper cross section (311) of the fixed column (31). The lower sleeve (33) has a circular hole (332), and a lower knob (333) is rotatably installed inside the circular hole (332). The diameter of the circular hole (332) is 1 / 2 of the width of the upper cross section (311) of the fixed column (31). The bottom of the upper pressure block (34) and the top of the lower pressure block (35) are respectively provided with conical inclined surfaces (5), and an annular groove (6) is provided on the conical inclined surface (5). The angle between the axis of the annular groove (6) and the axis of the lower pressure block (35) is 10°-15°, and the part of the annular groove (6) away from the wafer (2) is lower than the part that contacts the wafer (2).

2. The wafer fixing device according to claim 1, characterized in that: The width of the cut surface (311) is 2 / 3 of the diameter of the fixed column (31). A scale bar (312) is provided on the cut surface (311) of the fixed column (31). A circular boss (313) is provided at the bottom of the fixed column (31). A metal tube (314) is provided inside the center of the fixed column (31). The length of the metal tube (314) is equal to the length of the fixed column (31).

3. The wafer fixing device according to claim 1, characterized in that: The power assembly (4) includes an air pump (41), an air pipe (42), and a telescopic pipe (43). The air pump (41) is fixedly installed inside the support platform (1). One end of the air pipe (42) is fixedly installed on the air pump (41), and the other end of the air pipe (42) is fixedly installed on one end of the telescopic pipe (43). The other end of the telescopic pipe (43) is fixedly installed on the bottom side of the fixed column (31). The telescopic length of the telescopic pipe (43) is equal to the moving distance of the fixed column (31).

4. The wafer fixing device according to claim 1, characterized in that: The support platform (1) has a rectangular groove (11) inside. A circular groove (12) is formed at the center of the rectangular groove (11). Four arc-shaped through holes (13) are formed radially at the top of the support platform (1) through the center of the circle. The arc-shaped through holes (13) are located above the circular grooves (12) and are interconnected with the circular grooves (12). The length of the arc-shaped through holes (13) is equal to the length of the circular grooves (12), and the length of the arc-shaped through holes (13) is 3 / 4 of the diameter of the support platform (1).

5. A testing device, comprising the wafer fixing device as described in claim 2, characterized in that, The detection device includes a metal sheet (7), a contact (8), a vision sensor, and a control unit. The metal sheet (7) is fixedly installed on the bottom inner wall of the upper sleeve (32) and the top inner wall of the lower sleeve (33). The contact (8) is fixedly installed on the top outer side of the upper pressure block (34) and the bottom outer side of the lower pressure block (35). The contact (8) is located on the line connecting the center of the upper pressure block (34) and the lower pressure block (35) with the center of the wafer (2). The metal sheet (7) and the contact (8) are connected by a wire, and the wire is located inside the metal tube (314). The vision sensor is fixedly installed above the wafer (2).

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