Wafer cleaning device
By improving the shield structure and support design of the wafer cleaning device, the problems of liquid backsplashing and support breakage were solved, resulting in higher product yield and equipment reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2026-03-06
AI Technical Summary
Existing wafer cleaning equipment is prone to liquid splashing back onto the wafer surface during the cleaning process, and the protective cover support is easily broken, affecting product yield and equipment uptime.
A protective structure comprising frustum-shaped and cylindrical covers was designed, combined with a bracket design featuring beveled connections, a three-layer protective structure, and a sealing ring to prevent liquid backflow and enhance the robustness of the bracket.
It effectively prevents cleaning fluid from splashing back onto the wafer surface, improving product yield. At the same time, the support is more robust, reducing maintenance time and increasing equipment uptime.
Smart Images
Figure CN223979035U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of semiconductor manufacturing technology, and specifically relates to a wafer cleaning device. Background Technology
[0002] In the wafer manufacturing process, wafer cleaning is an essential step to obtain high-quality wafers. Its main purpose is to remove organic contaminants, particles, metals, and other impurities from the wafer surface, facilitating subsequent chip manufacturing. Existing wafer cleaning machines are divided into single-wafer cleaning machines and tank-type cleaning machines. Single-wafer cleaning machines typically remove various impurities from the wafer surface by spraying chemical solutions through spray nozzles. After cleaning, the wafer rotates at high speed and is dried by nitrogen blowing. The specific cleaning steps are as follows: the wafer is first conveyed from the wafer cassette to the cleaning unit by a transfer device, then cleaned and dried in the cleaning unit, and finally conveyed back to the wafer cassette by the transfer device. Therefore, the cleaning unit is the most critical component of the cleaning machine, directly affecting the product quality.
[0003] In the actual wafer cleaning process, after a wafer is placed into the cleaning device, the device's shield rises to surround the wafer. The stage then rotates the wafer at a low speed while the nozzles continuously spray chemical solution or water to clean it. After cleaning, the wafer rotates at high speed and is dried by nitrogen gas. Finally, the shield of the cleaning device descends, and the wafer is removed. During this process, because the wafer is rotating while the chemical solution is being sprayed, the liquid disperses in all directions under centrifugal force and may hit the inside of the shield. Most of the liquid flows down the shield, while a small amount splashes back onto the wafer. When any liquid splashes back onto the wafer, it can cause abnormal surface contamination after cleaning. Therefore, the shield needs to be improved to prevent liquid from splashing onto the wafer surface. Additionally, each shield currently has two supports for raising and lowering the shield. Due to the unreasonable design of the existing supports, the fixing screws on both sides frequently break, and replacing the supports takes a long time, severely affecting the equipment's uptime.
[0004] Therefore, further improvements to this wafer cleaning device are needed to prevent liquid from splashing back onto the wafer surface during the cleaning process, and to make the shield support more robust and prevent it from breaking. This has significant technical value for improving product yield and equipment uptime. Utility Model Content
[0005] The purpose of this invention is to provide a wafer cleaning device to address the shortcomings of existing technologies.
[0006] The objective of this utility model is achieved through the following technical solution:
[0007] A wafer cleaning apparatus includes a cavity with an opening at the top, a wafer support mechanism, and a liftable shield; the wafer support mechanism is located at the center of the cavity; the shield is disposed between the cavity and the wafer support mechanism and is used to rise and surround the wafer during wafer cleaning.
[0008] The protective cover comprises, from top to bottom, a frustum-shaped cover and a cylindrical cover; the inclination angle α of the frustum-shaped cover is 15 to 25°;
[0009] The bottom of the cylindrical cover is connected to a bracket; the bracket includes, from top to bottom, a horizontal connecting column, an inclined transition section, a vertical connecting plate, and a horizontal connecting plate; the horizontal connecting column and the horizontal connecting plate are respectively used to connect to the cylindrical cover and the lifting mechanism.
[0010] Preferably, the horizontal connecting column is provided with multiple mounting holes and positioning posts. The mounting holes are used to connect to the cylindrical cover through screws, and the positioning posts are used for installation and positioning.
[0011] Preferably, the tilt angle β of the tilted transition section is 40 to 50°.
[0012] Preferably, the cavity includes a base and a fixing ring fixed above the base, the base being used to fix it to the cleaning machine; the bottom of the base has multiple through holes for the pipelines of the cleaning machine to pass through;
[0013] The protective cover is located inside the fixing ring.
[0014] Preferably, there are three protective covers, which are arranged from the outside to the inside as follows: an outer protective cover fitted inside the fixing ring, a middle protective cover fitted inside the outer protective cover, and an inner protective cover fitted inside the middle protective cover.
[0015] The bottom of the outer protective cover, the middle protective cover, and the inner protective cover are all connected to the bracket, which can be raised and lowered individually.
[0016] Preferably, the bottom of the outer protective cover is provided with an outwardly extending boss;
[0017] The protrusion is provided with a sealing ring for sealing the shield during wafer cleaning.
[0018] Preferably, both the inner protective cover and the middle protective cover are provided with drainage pipes at their bottoms.
[0019] Preferably, the wafer support mechanism includes a stage, a support rod, and a hollow fixing rod, wherein the fixing rod is fixedly connected to the bottom of the stage, and the support rod is located inside the fixing rod;
[0020] The platform is equipped with multiple supports for supporting and fixing the wafer;
[0021] The fixing rod is connected to a driving device, which is used to drive the stage and the wafer located on the stage to rotate during wafer cleaning.
[0022] Preferably, the stage is further provided with a sensor at its center for detecting whether a wafer is mounted on the stage.
[0023] Preferably, the support rod has a through hole in the middle for the sensor circuit to pass through.
[0024] This application further improves the wafer cleaning apparatus by enhancing the shield and optimizing the shield support. This prevents liquid from splashing back onto the wafer surface during cleaning, effectively improving product yield. It also makes the shield support more robust, preventing breakage after prolonged lifting and lowering operations, thus reducing maintenance time and increasing uptime. Therefore, the wafer cleaning apparatus provided in this application has significant practical value and technological improvement implications for semiconductor wafer processing cleaning technology. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the overall cleaning device;
[0026] Figure 2 This is a cross-sectional schematic diagram of the cleaning device;
[0027] Figure 3 This is a cross-sectional schematic diagram of the cleaning device;
[0028] Figure 4 This is a schematic diagram of the bottom of the cleaning device;
[0029] Figure 5 This is a schematic diagram of the overall cross-section of the cleaning device;
[0030] Figure 6 This is a schematic diagram of the protective cover of the cleaning device;
[0031] Figure 7 This is a schematic diagram of the intermediate support mechanism of the cleaning device;
[0032] Figure 8 This is a schematic diagram of the support frame for the cleaning device.
[0033] Explanation of reference numerals in the attached figures:
[0034] 1-Outer protective cover; 2-Fixing ring; 3-Connecting screw; 4-Base; 5-Chip; 6-Middle protective cover; 7-Inner protective cover; 71-Frustoconical cover; 72-Cylindrical cover; 73-Boss; 8-Fixing rod; 9-Bracket; 91-Horizontal connecting column; 92-Inclined transition section; 93-Vertical connecting plate; 94-Horizontal connecting plate; 95-Positioning column; 10-Support; 11-Platform; 12-Sensor; 13-Circuit; 14-Support rod; 15-Drain pipe; 16-Sealing ring. Detailed Implementation
[0035] A preferred embodiment of this application provides a wafer cleaning apparatus, such as... Figures 1-8 As shown, the device includes a cavity with an opening at the top, a wafer support mechanism, and a liftable shield; the shield can be raised and lowered by the lifting mechanism. The wafer support mechanism is located at the center of the cavity and is used to support the wafer; the shield is located between the cavity and the wafer support mechanism and is used to rise and surround the wafer 5 during wafer cleaning to prevent cleaning fluid from splashing to the outside during the cleaning process.
[0036] The shield comprises, from top to bottom, a frustum-shaped shield 71 and a cylindrical shield 72. The upper part of the shield is frustum-shaped, curved inward, and has a circular hole at the top for accommodating the wafer support mechanism. The inclination angle α of the frustum-shaped shield in this application is set to 15-25°, which is about 10° smaller than that in the prior art. With this inclination angle, the height of the cleaning fluid after splashing back onto the inner side of the shield is lower than the height of the wafer 5. Therefore, the cleaning fluid will not contaminate the wafer again after splashing back, reducing wafer contamination and improving wafer yield.
[0037] A support 9 is connected to the bottom of the cylindrical cover 72. The support 9, from top to bottom, includes a horizontal connecting column 91, an inclined transition section 92, a vertical connecting plate 93, and a horizontal connecting plate 94. The horizontal connecting column 91 connects to the bottom of the cylindrical cover 72, thus fixing the cover to the entire support. The horizontal connecting plate 94 connects to a lifting mechanism, which can lift the cover during wafer cleaning for protection. This application provides an inclined transition section between the horizontal connecting column and the vertical connecting plate, changing the connection angle from a conventional right angle to a bevel. With a right-angle connection, the force is relatively concentrated at the connection point, especially at the corner, easily leading to stress concentration. With a bevel connection, the force can be transmitted along the bevel direction, lengthening the force path and allowing for more even distribution of force on the horizontal connecting column and the vertical connecting plate, reducing localized stress concentration and improving overall compressive strength. Therefore, changing the beveled side increases the compressive strength of bracket 9, making the bracket more robust and less prone to breakage, reducing the number of maintenance times and time, and improving the equipment's uptime.
[0038] Preferably, two supports are connected to the bottom of each shield.
[0039] Preferably, the horizontal connecting column 91 is provided with multiple mounting holes and positioning columns 95. The mounting holes are used for screws to pass through and connect to the cylindrical cover, and the positioning columns 95 are used for installation and positioning. The horizontal connecting plate 94 is provided with multiple holes for fixing the bracket to the lifting mechanism.
[0040] Preferably, the tilt angle β of the inclined transition section 92 is 40 to 50°.
[0041] Preferably, the cavity includes a base 4 and a fixing ring 2 fixed above the base. The base 4 is used to fix it to the cleaning machine. The bottom of the base 4 has multiple through holes for the pipelines of the cleaning machine to pass through. The fixing ring 2 is preferably connected and fixed to the base 4 by four connecting screws 3.
[0042] The protective cover is located inside the retaining ring 2. The retaining ring 2 is used to position and protect the internal mechanism.
[0043] Preferably, there are three protective covers, which are arranged from the outside to the inside as follows: an outer protective cover 1 fitted inside the fixing ring, a middle protective cover 6 fitted inside the outer protective cover 1, and an inner protective cover 7 fitted inside the middle protective cover 6; the bottom of the outer protective cover 1, the middle protective cover 6 and the inner protective cover 7 are all connected to a bracket 9, which can be raised and lowered individually.
[0044] Preferably, the bottom of the outer shield 1 is provided with an outwardly extending boss 73, and a sealing ring 16 is provided on the boss for sealing the outer shield during wafer cleaning.
[0045] Furthermore, the sidewalls of the middle shield 6 and the outer shield 1, as well as the sidewalls of the inner shield 7 and the middle shield 6, are all fitted together with concave and convex shapes. This allows the outer shield to fit over the adjacent inner shield, and the inner shield to effectively prevent cleaning fluid from splashing outwards onto the outer shield. At the same time, the grooves in the concave and convex fits also serve as clearance grooves to allow space for the movement of each shield, without affecting the individual movement of each shield.
[0046] Preferably, both the inner protective cover 7 and the middle protective cover 6 are provided with two drainage pipes 15 at their bottom.
[0047] This application employs a three-layered protective shield structure, each designed for different cleaning solutions to prevent reactions between the two solutions. Specifically, the inner shield 7 is located at the innermost layer, close to the wafer support mechanism. The middle shield 6 is situated between the inner shield 7 and the outer shield 1. The outer shield 1 is located at the outermost layer, close to the fixing ring 2, and moves up and down within the fixing ring 2. When the outer shield 1 rises, the sealing ring 16 is positioned between the boss 73 and the fixing ring 2, sealing the gap between the outer shield and the fixing ring. This seals the cleaning device, preventing cleaning solution from splashing to the outside. Drain pipes at the bottom of the middle and inner shields discharge waste solutions from the outer shield 1 and the middle shield 6, respectively. The waste solution is discharged into the base 4 via the drain pipe 15, while the waste solution from the inner shield 7 is discharged directly into the base 4. Finally, the waste solution is discharged to the outside of the cleaning device through the circular hole in the base 4.
[0048] Preferably, the wafer support mechanism includes a stage 11, a support rod 14, and a hollow fixing rod 8. The fixing rod 8 is fixedly connected to the bottom of the stage 11, and the support rod 14 is located inside the fixing rod 8. The stage 11 is provided with a plurality of supports 10, preferably six, with adjacent supports spaced 60° apart, for supporting and fixing the wafer 5.
[0049] The fixed rod 8 is connected to a drive device, which is used to drive the stage and the wafer 5 located on the stage to rotate during wafer cleaning, thereby completing the purpose of cleaning and drying the wafer 5.
[0050] Preferably, a sensor 12 is also provided at the center of the stage 11 for detecting whether a wafer is mounted on the stage. More preferably, a through hole is provided in the middle of the support rod 14 for the sensor circuit 13 to pass through.
[0051] As those skilled in the art will understand, the cleaning machine is equipped with nozzles to spray the top of the wafer and clean its upper surface. Furthermore, the stage surface is also equipped with nozzles, and the support rod is equipped with a cleaning pipeline for supplying cleaning fluid to the nozzles. Through these nozzles, cleaning fluid can be sprayed onto the bottom of the wafer to clean its lower surface.
[0052] Figure 1 and Figure 3 This is the state when the three-layer shield is lowered, and Figure 2 and Figure 5 This is the state when the three protective covers are raised. When the three protective covers are lowered, the wafer 5 is placed on the support 10. The sensor detects the presence of the wafer and sends a command to the machine. Then, the three protective covers are raised to cover the wafer 5 and begin cleaning. During the cleaning process, different liquids correspond to different protective covers. After the first liquid is used to clean the wafer, the inner protective cover 7 is lowered. After the second liquid is used to clean the wafer, the middle protective cover 6 is lowered. The outer protective cover 1 is used to clean the wafer 5 with the third liquid and to dry the wafer 5. When all the protective covers are lowered, the wafer removal device removes the wafer 5, and the cleaning is completed.
[0053] Therefore, this application further improves the wafer cleaning apparatus by improving the shield and optimizing the shield support, so that liquid will not splash back onto the wafer surface during the cleaning process, which can effectively improve the product yield. At the same time, the shield support is made more robust and will not break after long-term lifting and lowering operations, which can effectively reduce the maintenance time of the cleaning machine and improve the uptime. Therefore, the wafer cleaning apparatus provided by this application has good practical value and technical improvement significance in semiconductor wafer processing cleaning technology.
[0054] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from its spirit and scope. Thus, if such modifications and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and modifications.
Claims
1. A wafer cleaning device, comprising an open-topped cavity, a wafer supporting mechanism and a liftable shield; the wafer supporting mechanism is located in the center of the cavity; the shield is arranged between the cavity and the wafer supporting mechanism and is used to surround the wafer when the wafer is cleaned; characterized in that, the shield comprises a frustoconical shield body and a cylindrical shield body from top to bottom; the inclination α of the frustoconical shield body is 15-25°; the bottom of the cylindrical shield body is connected with a support; the support comprises a horizontal connecting column, an inclined transition section, a vertical connecting plate and a horizontal connecting plate from top to bottom; the horizontal connecting column and the horizontal connecting plate are respectively used to connect with the cylindrical shield body and a lifting mechanism.
2. The wafer cleaning device according to claim 1, characterized in that, a plurality of mounting holes and positioning columns are arranged on the horizontal connecting column; the mounting holes are used to pass through screws to connect with the cylindrical shield body; the positioning columns are used to install positioning.
3. The wafer cleaning device according to claim 1, characterized in that, the inclination angle β of the inclined transition section is 40-50°.
4. The wafer cleaning device according to claim 1, characterized in that, the cavity comprises a base and a fixing ring fixed above the base; the base is used to be fixed with a cleaning machine; a plurality of through holes are arranged on the bottom of the base and are used for the pipeline of the cleaning machine to pass through; the shield is located inside the fixing ring.
5. The wafer cleaning device according to claim 4, characterized in that, the shield is three, from outside to inside, an outer shield sleeved inside the fixing ring, a middle shield sleeved inside the outer shield and an inner shield sleeved inside the middle shield; the bottom of the outer shield, the middle shield and the inner shield are all connected with the support and can be lifted individually.
6. The wafer cleaning device according to claim 5, characterized in that, the bottom of the outer shield is provided with a outwardly extending boss; a sealing ring is arranged on the boss and is used to seal the shield when the wafer is cleaned.
7. The wafer cleaning device according to claim 5, characterized in that, the bottom of the inner shield and the middle shield are both provided with a drain pipe.
8. The wafer cleaning device according to claim 1, characterized in that, the wafer supporting mechanism comprises a carrier, a supporting rod and a hollow fixing rod; the fixing rod is fixedly connected to the bottom of the carrier; the supporting rod is located inside the fixing rod; a plurality of supports are arranged on the carrier and are used to support and fix the wafer; the fixing rod is connected with a driving device and is used to drive the carrier and the wafer located on the carrier to rotate when the wafer is cleaned.
9. The wafer cleaning device according to claim 8, characterized in that, a sensor is further arranged in the center of the carrier and is used to detect whether the carrier carries the wafer.
10. The wafer cleaning device according to claim 9, characterized in that, a through hole is arranged in the middle of the supporting rod and is used for the line of the sensor to pass through.