Developing solution back flow prevention device

Abstract

The invention discloses a developing solution back flow prevention device, which comprises an annular shielding assembly and a lifting assembly, and the lifting assembly is used for driving the annular shielding assembly to lift so as to be close to or far away from a wafer arranged on a wafer carrying table from the back surface. The anti-backflow device provided by the invention can rotate synchronously with the wafer carrying table and does not cause friction with the wafer, the annular shielding assembly can be tightly attached to the back surface of the wafer to effectively block backflow of the developing solution, and the annular shielding assembly can also form an annular airflow shielding ring to change the flow direction of the developing solution, so that the developing solution is prevented from flowing back. The developing solution is further prevented from flowing to a position which cannot be cleaned by the wafer carrying table or the back washing assembly, the lifting assembly can prevent the annular shielding assembly from forming relatively strong impact force when the annular shielding assembly is in contact with the wafer, and the fitting precision of the annular shielding assembly and the wafer is improved.

Description

Technical Field

[0001] The present application relates to the field of wafer production and manufacturing in the semiconductor industry, and in particular to a device for preventing backflow of developer solution. Background Art

[0002] The photolithography process in the manufacture of silicon carbide power semiconductors is an important process for forming structural patterns. The photolithography process usually consists of three parts: coating, exposure, and development. The development process is to place the wafer on a vacuum stage, spray the developer on the wafer surface, and keep the wafer stationary or rotate at a low speed to allow the developer to fully react with the photoresist to complete the development and form the pattern. The quality of the developed pattern has a great impact on the subsequent processes and finished products.

[0003] When developing, the wafer surface needs to be covered with developer and kept still or slightly rotated to allow the developer to fully react with the exposed photoresist. When the developer exceeds the surface tension, a small amount of developer will flow to the back of the edge, contaminating the back of the wafer and the wafer stage. At the same time, the wafer will contaminate the subsequent equipment when it contacts the equipment.

[0004] At present, in response to such problems, the patent with announcement number CN204903943U discloses a developing device to prevent contamination of the back side of the wafer. Although it can solve the problem of contamination of the back side of the wafer, it has the following defects: when the developing time is too long or the wafer carrier is not flat enough, the developer will still flow into the back of the wafer when it accumulates on the surface of the baffle to a certain extent, contaminating the wafer carrier. In addition, in the existing improved technology, the wafer rotates with the carrier and the guard ring is fixed with the rotating baffle. The friction between the guard ring and the wafer will cause damage to the back side of the wafer, and because the baffle is adjusted manually, the accuracy of the guard ring and the wafer cannot be guaranteed. Summary of the invention

[0005] One purpose of the present application is to provide a device to prevent developer backflow, thereby solving the problem of developer backflow contaminating the back side of the wafer.

[0006] Another object of the present application is to provide a device to prevent developer backflow, so as to solve the problem of wafer edge being easily susceptible to wear in existing devices and to improve the reliability and safety of the developer backflow prevention device.

[0007] To achieve the above objectives, the technical solution adopted in this application is: a device for preventing backflow of developer, comprising an annular shielding component and a lifting component, wherein the lifting component is used to drive the annular shielding component to rise and fall, so as to approach or move away from the back side of a wafer set on a wafer carrier.

[0008] Preferably, a plurality of air holes are arranged at intervals on the annular shielding assembly, wherein the air holes are suitable for blowing out airflow, and the air holes face the outside of the annular shielding assembly.

[0009] Preferably, the air hole is inclined upward toward the outside of the annular shielding assembly, and the angle between the direction of the air flow ejected from the air hole and the central axis of the annular shielding assembly is 10°~80°.

[0010] Preferably, the annular shielding assembly has an annular air cavity therein, each of the air holes is connected to the annular air cavity, and the annular shielding assembly also includes a gas pipeline, which connects an external gas source with the annular air cavity.

[0011] Preferably, in any of the developer backflow prevention devices, the annular shielding assembly comprises an annular shielding ring and an elastic sealing ring wrapped outside the annular shielding ring.

[0012] Preferably, any of the devices for preventing developer backflow further includes a wafer stage and a driving assembly, wherein the wafer stage is suitable for adsorbing wafers, and the wafer stage and the lifting assembly are arranged on the driving assembly, so that the driving assembly drives the wafer stage and the lifting assembly to rotate synchronously, and at the same time, the lifting assembly drives the annular shielding assembly to rotate synchronously.

[0013] As a preference, it further includes a back wash component, which is suitable for spraying cleaning liquid to clean the back side of the wafer on the wafer carrier. The back wash component includes a plurality of nozzles, each of which is arranged on the driving component, so that each of the nozzles rotates synchronously with the wafer carrier.

[0014] Preferably, a pressure sensor is provided on the annular shielding assembly, and the pressure sensor is communicatively connected with the lifting assembly.

[0015] As a preferred embodiment, a wafer developing method comprises the steps of: S10, placing a wafer to be developed on a wafer stage, keeping the wafer stage rotating and spraying a developing solution on the front side of the wafer; S20, reducing the rotation speed of the wafer stage, and moving an annular shielding component that rotates synchronously with the wafer stage upward so that it contacts the back side of the wafer; S30, stopping spraying the developer, reducing the rotation speed of the wafer stage, and entering the development stage; S40, after the development is completed, the annular shielding assembly is moved downward to be away from the back side of the wafer, and then a cleaning liquid is sprayed on the back side of the wafer for back washing.

[0016] Further preferably, in step S30, after reducing the rotation speed of the wafer stage, an air flow is sprayed toward the edge of the wafer through the air holes on the annular shielding assembly, thereby forming an annular shielding air flow on the back side of the wafer, and after the development is completed, the air flow is turned off; In step S20, when the pressure sensor on the annular shielding assembly detects that the pressure between the annular shielding assembly and the back side of the wafer exceeds a preset value, the upward movement of the annular shielding assembly is stopped.

[0017] Compared with the prior art, the beneficial effects of this application are: (1) The annular shielding assembly in the present application can be closely attached to the back side of the wafer. If the developer flows backward, it can be blocked from flowing to the position that the wafer carrier or the back washing assembly cannot clean.

[0018] (2) In the present application, nitrogen gas is sprayed through the gas pipeline to form an airflow shielding ring, which can change the flow direction of the developer and further prevent it from flowing to the position that the wafer carrier or the back washing component cannot clean.

[0019] (3) The anti-backflow device in the present application can rotate synchronously with the wafer stage and will not cause friction with the wafer, thereby reducing the risk of wafer damage.

[0020] (4) The anti-backflow device in the present application has a three-link structure lifting assembly and a pressure sensor. The three-link structure is suitable for adjusting the required height of the anti-backflow device in different operation steps. The pressure sensor can control the lifting speed of the lifting assembly to avoid the formation of a strong impact force when the annular shielding assembly contacts the wafer, thereby improving the accuracy of the anti-backflow device and the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the overall structure of an embodiment of the present invention (the wafer is not shown).

[0022] Figure 2 Schematic diagram of the structure of the backflow prevention device in contact with the back side of the wafer in an embodiment of the present invention (the wafer is not shown).

[0023] Figure 3 Schematic diagram of the structure of the initial position of the anti-backflow device in an embodiment of the present invention (the wafer is not shown).

[0024] Figure 4 It is a schematic diagram of the connection structure between the anti-backflow device and the lifting assembly in an embodiment of the present invention.

[0025] Figure 5 It is a partial structural schematic diagram of the anti-backflow device in an embodiment of the present invention.

[0026] In the figure: 10, annular shielding assembly; 11, air hole; 12, gas pipeline; 13, annular shielding ring; 14, elastic sealing ring; 20, lifting assembly; 30, driving assembly; 40, back washing assembly; 50, wafer carrier; 51, vacuum adsorption hole. DETAILED DESCRIPTION

[0027] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0028] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and cannot be understood as limiting the specific scope of protection of the present application.

[0029] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0030] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0031] On the one hand, in view of the problem that there is a gap between the wafer and the fixed baffle in the existing technology for preventing the backflow of developer, when the development time is too long, the development is excessive, and the wafer carrier is not leveled, the back of the wafer is still easily contaminated by the developer. On the other hand, in view of the existing technology, there will be contact between the developer backflow prevention ring and the wafer. At the same time, the wafer rotates with the carrier and the ring is fixed with the rotating baffle. The friction will cause damage to the back of the wafer, and because the baffle is adjusted manually, its accuracy cannot be guaranteed. The present application proposes a new device for preventing the backflow of developer, which enables the developer backflow prevention device to be in close contact with the wafer and rotate with the wafer at the same time, thereby not only preventing the developer from contaminating the wafer but also not causing damage to the wafer. The implementation method of the present application is further described below in conjunction with the accompanying drawings.

[0032] The present application relates to a device for preventing developer backflow, including an annular shielding component 10 and a lifting component 20. The lifting component 20 is used to drive the annular shielding component 10 to rise and fall, so as to approach or move away from a wafer disposed on a wafer carrier 50 from the back.

[0033] In some embodiments, a plurality of air holes 11 are arranged at intervals on the annular shielding assembly 10, and the air holes 11 are suitable for blowing out airflow, and the air holes 11 are facing the outside of the annular shielding assembly 10. During the wafer development process, the airflow ejected from the annular shielding assembly 10 can change the flow direction of the backflow developer, blocking it from flowing to the wafer carrier 50 or a position that cannot be cleaned by the back washing device.

[0034] In some embodiments, the air hole 11 is tilted upward toward the outside of the annular shielding assembly 10, and the angle between the direction of the air flow ejected from the air hole 11 and the central axis of the annular shielding assembly 10 is 10°~80°. The air flow ejected from the upward-tilted air hole 11 can reduce the gravity of the developer overflowing from the edge of the wafer, and most of the developer will be blown away by the ejected air flow before the developer approaches the annular shielding assembly 10, which not only reduces the direct impact of the developer on the annular shielding assembly 10, but also reduces the volume of the developer that the annular shielding assembly 10 needs to block.

[0035] In some embodiments, the angle between the direction of the air flow ejected from the air hole 11 and the central axis of the annular shielding assembly 10 is 30°~60°. At this time, the air flow ejected within this angle range can form an effective impact force on the developer flowing out of the wafer, which not only ensures the effective removal of the developer, but also avoids excessive splashing and equipment wear.

[0036] In some embodiments, the angle between the direction of the air flow ejected from the air hole 11 and the central axis of the annular shielding assembly 10 is 40°~50°, which can form a more effective impact force on the developer flowing out of the wafer and ensure the smooth and effective removal of the developer.

[0037] In some embodiments, the annular shielding assembly 10 has an annular air cavity therein, and each air hole 11 is connected to the annular air cavity. The annular shielding assembly 10 also includes a gas pipeline 12, and the gas pipeline 12 connects an external gas source and the annular air cavity, so that the gas source can be continuously filled into the annular air cavity, and air flow is continuously ejected from the annular air cavity to form an air flow shielding circle.

[0038] In some embodiments, the annular shielding assembly 10 includes an annular shielding ring 13 and an elastic sealing ring 14 wrapped around the annular shielding ring 13. The elastic sealing ring 14 helps to reduce direct collision between the annular shielding ring 13 and the wafer surface, thereby protecting the wafer contact surface from damage.

[0039] In some embodiments, the annular shielding ring 13 is made of anti-corrosion materials such as ceramics, stainless steel, and aluminum alloy to prevent leakage after the annular shielding ring 13 is corroded during use and to increase the service life of the equipment.

[0040] In some embodiments, the elastic sealing ring 14 is made of fluororubber, silicone rubber or an anti-corrosion coating is applied on the rubber surface to prevent the developer from corroding the internal annular shielding ring 13, thereby preventing the annular shielding assembly 10 from being corroded and preventing the developer from backflowing. The annular shielding assembly 10 can also be used to extend the service life of the annular shielding assembly 10 and reduce maintenance costs.

[0041] In some embodiments, the device for preventing backflow of developing solution also includes a wafer stage 50 and a driving assembly 30. The wafer stage 50 is suitable for adsorbing the wafer. The wafer stage 50 and the lifting assembly 20 are arranged on the driving assembly 30, so that the driving assembly 30 drives the wafer stage 50 and the lifting assembly 20 to rotate synchronously. At the same time, the lifting assembly 20 drives the annular shielding assembly 10 to rotate synchronously, so that the annular shielding assembly 10 will not generate friction with the surface of the rotating wafer during development, thereby avoiding damage to the wafer.

[0042] In some embodiments, the device for preventing the developer from flowing back further includes a backwash assembly 40, which is suitable for spraying a cleaning liquid to clean the back side of the wafer on the wafer carrier 50. The backwash assembly 40 includes a plurality of nozzles for spraying deionized water (DI Water) upward to clean the developer remaining on the back side of the wafer. Each nozzle is disposed on the driving assembly 30, so that each nozzle rotates synchronously with the wafer carrier 50, so that each part of the back side of the wafer can be cleaned.

[0043] In some embodiments, the position where the deionized water sprayed by the back wash component 40 contacts the wafer is larger than the contact position between the outer ring of the wafer carrier 50 and the wafer, and smaller than the contact position between the inner ring of the annular shielding component 10 and the wafer. The range outside the contact position of the back wash component 40 can be cleaned. Therefore, if there is slight water stain on the elastic sealing ring 14 and it contacts the back of the wafer, no residue will be left.

[0044] In some embodiments, a pressure sensor is provided on the annular shielding assembly 10, and the pressure sensor is communicated with the lifting assembly 20 to control the rise and fall of the annular shielding assembly 10, so as to realize automatic and precise contact of the annular shielding assembly 10 with the wafer surface, thereby avoiding leakage of the developer due to contact error.

[0045] In some embodiments, the annular shielding assembly 10 rotates together with the wafer carrier 50 by installing a rotary joint on the driving assembly 30. The rotary joint can transfer a static medium source into a dynamic medium source by rotation. Specifically, the installed rotary joint can realize the simultaneous rotation of the annular shielding assembly 10 and the driving assembly 30 to solve the problem of the wafer edge being susceptible to friction, and can also realize the delivery of gas into the annular shielding assembly 10 while rotating.

[0046] In some embodiments, the rotary joint may be a single-channel rotary joint or a multi-channel rotary joint, wherein the single-channel rotary joint adopts threaded connection and is suitable for single medium transmission, and the multi-channel rotary joint adopts flange connection and is suitable for simultaneous multi-media transmission.

[0047] In some embodiments, the rotary joint is a multi-channel rotary joint, which can adapt to larger-sized devices and the transmission of high-pressure media. In addition, the multi-channel rotary joint can also realize the simultaneous transmission of multiple media.

[0048] In some embodiments, during development, nitrogen is introduced into the gas pipeline 12 connected to the annular shielding assembly 10. Nitrogen is a chemically inert gas that will not react with the developer or the wafer surface, thereby ensuring the stability and safety of the development process.

[0049] In some embodiments, when the annular shielding assembly 10 is in the initial position, if water or other liquids are stained on the elastic sealing ring 14, the annular shielding assembly 10 can be rotated at high speed to keep its surface dry when the wafer rotates at high speed.

[0050] In some embodiments, the lifting assembly 20 is a three-link structure that can rise and fall. Compared with ordinary support rods and telescopic rods, the three-link structure has better flexibility and stability when rising and falling. During the wafer development process, the annular shielding assembly 10 can be quickly lifted and lowered, thereby improving the wafer development efficiency.

[0051] In some embodiments, the wafer carrier 50 is a vacuum carrier, and a vacuum adsorption hole 51 is provided on the surface of the wafer carrier 50. The wafer is fixed by vacuum adsorption force. Vacuum gas can be introduced into the wafer carrier 50 through a multi-channel rotary joint to adsorb and fix the wafer. At the same time, nitrogen gas is introduced into the annular shielding assembly 10 to form an airflow shielding ring to prevent the developer from flowing to the back of the wafer.

[0052] According to the above embodiments, the present application proposes a device for preventing developer backflow: like Figure 1~Figure 5As shown, the device for preventing backflow of developer includes an annular shielding component 10, an air hole 11, a gas pipeline 12, an annular shielding ring 13, an elastic sealing ring 14, a lifting component 20, a driving component 30, a back washing component 40, a wafer carrier 50, and a vacuum adsorption hole 51. During the development process, the wafer is placed on the wafer carrier 50, and a vacuum adsorption hole 51 is arranged at the center of the wafer carrier 50, and vacuum gas is introduced to adsorb the wafer. The annular shielding component 10 includes an annular shielding ring 13 and an elastic sealing ring 14, wherein the annular shielding ring 13 is made of aluminum alloy with strong wear resistance and corrosion resistance, and the elastic sealing ring 14 is made of fluororubber with better corrosion resistance and stability, thereby improving the service life of the annular shielding component 10, and the elastic sealing ring 14 is wrapped in the annular Outside the shielding ring 13, the annular shielding ring 13 is protected, and multiple air holes 11 with uniform distances are opened on the arc surface in the direction of the air flow direction ejected from the air hole 11 and the central axis of the annular shielding component 10 at an angle of 45°. A pressure sensor is installed between the elastic sealing ring 14 and the annular shielding ring 13. After the wafer is placed on the wafer carrier 50, the pressure sensor is used to control the three-link folding lifting assembly 20. The lifting assembly 20 installed under the annular shielding assembly 10 slowly rises. When the pressure sensor senses that the annular shielding assembly 10 is in contact with the back of the wafer, it stops moving. The gas pipeline 12 connects nitrogen to the air cavity of the annular shielding ring 13 through a rotary joint, and then sprays it out through the air hole 11, changing the backflow direction of the developer and preventing the backflow of the developer. At the same time, the back washing assembly 40 located on the driving assembly 30 sprays deionized water upward to clean the developer remaining on the surface of the wafer, further improving the quality of the wafer.

[0053] In the prior art, the back of the wafer is prone to backflow due to long developing time, overdevelopment or insufficient flatness of the wafer stage 50. When the developer accumulates on the baffle surface to a certain extent, it will still flow to the back of the wafer, or even flow into the wafer stage 50. Although the backwash device can clean some of the contamination, since the backwash device sprays liquid, the contact point between the spray liquid and the wafer cannot be too close to the wafer vacuum stage, so an empty area that cannot be cleaned is formed.

[0054] The present application can effectively block the developer backflow of the wafer, so that the developer backflow cannot flow into the vacant area that cannot be cleaned, and avoid the developer contaminating the vacant area that cannot be cleaned. In addition, in the present application, the annular shielding component 10 is introduced with nitrogen to form an airflow shielding ring to prevent the developer backflow. While the annular shielding component 10 blocks the developer backflow, the airflow shielding ring further strengthens the resistance of the developer backflow, thereby preventing the developer from contaminating the vacant area that cannot be cleaned.

[0055] In the prior art, contact will occur between the guard ring and the wafer. At the same time, the wafer rotates with the carrier and the guard ring is fixed with the rotating baffle. The existing friction will cause damage to the back of the wafer, and since the baffle is adjusted manually, its accuracy cannot be guaranteed.

[0056] The driving assembly 30, wafer stage 50, lifting assembly 20, and annular shielding assembly 10 of the present application can realize synchronous rotation, thereby preventing the annular shielding assembly 10 from damaging the wafer edge when the wafer rotates. In addition, the pressure sensor provided on the annular shielding assembly 10 of the present application, in conjunction with the use of the three-link lifting assembly 20, can ensure the accuracy of the annular shielding assembly 10 contacting the wafer.

[0057] The present application also proposes a wafer development method, comprising the steps of: S10, placing the wafer to be developed on the wafer stage 50, keeping the wafer stage 50 rotating and spraying the developing solution on the front side of the wafer; S20, reducing the rotation speed of the wafer stage 50, and moving the annular shielding assembly 10 that rotates synchronously with the wafer stage 50 upward to make it contact the back side of the wafer; S30, stopping spraying the developer, reducing the rotation speed of the wafer stage 50, and entering the development stage; S40, after the development is completed, the annular shielding assembly 10 is moved downward to be away from the back side of the wafer, and then a cleaning liquid is sprayed on the back side of the wafer for back washing.

[0058] In some embodiments, in step S30, after reducing the rotation speed of the wafer stage 50, an air flow is sprayed toward the edge of the wafer through the air holes 11 on the annular shielding assembly 10, thereby forming an annular shielding air flow on the back side of the wafer, and after the development is completed, the air flow is turned off; In step S20 , when the pressure sensor on the annular shielding assembly 10 detects that the pressure between the annular shielding assembly 10 and the back side of the wafer exceeds a preset value, the annular shielding assembly 10 stops moving upward.

[0059] The specific implementation steps of the developer backflow prevention device provided in this application are as follows: (1) The wafer to be developed is transferred to the vacuum wafer carrier 50, and vacuum gas is introduced into the wafer carrier 50 through a multi-channel rotary joint to adsorb the wafer onto the wafer carrier 50; (2) Spray the developer onto the surface of the wafer, and keep the wafer stage 50 rotating at a high speed of ≥1000 rpm; (3) The developer continues to be sprayed onto the wafer surface, and the rotation speed of the wafer carrier 50 is reduced to 30 r / min. At this time, the annular shielding assembly 10 is raised by the three-link lifting assembly 20, as shown in FIG. Figure 2 As shown, the ring shielding assembly 10 stops moving until the elastic sealing ring 14 contacts the back of the wafer and triggers the sensor; (4) Stop spraying the developer onto the wafer surface, reduce the speed of the wafer stage 50 to 10 r / min or stop rotating, and enter the development stage. The annular shielding assembly 10 is connected to nitrogen through the gas pipeline 12. At this time, the nitrogen is ejected through the air holes 11 on the annular shielding assembly 10 and blown to the back of the wafer to form an annular airflow shielding ring; (5) After the development is completed, stop the nitrogen purge. Figure 3 As shown, the three-link lifting assembly 20 drives the annular shielding assembly 10 down to the initial position; (6) Deionized water is sprayed on the front side of the wafer to clean the wafer surface and the wafer carrier 50 is rotated at a high speed of >1500r / min. At the same time, the back cleaning component 40 is turned on to clean the back side of the wafer; (7) The front deionized water and back wash components 40 are turned off, and the wafer carrier 50 is rotated at a high speed of >3000 r / min to dry the wafer surface and complete the development.

[0060] According to the specific application steps of the developer backflow prevention device in the present application, the developer backflow phenomenon is mostly caused by the development reaction stage, and the wafer carrier is at a stationary or low-speed rotating state at this time. The developer backflow prevention device of the present invention adds a three-link lifting support rod, which can control the anti-backflow device not to contact the back side of the wafer when the wafer carrier rotates at a high speed, and control the anti-backflow device to contact the back side when the wafer carrier rotates at a low speed or is stationary. In addition, since the developer backflow prevention device in the present application is connected to the wafer carrier and is driven by the same motor, friction with the back side of the wafer can be avoided even at a low speed, thereby not causing damage to the wafer.

[0061] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A device for preventing developer backflow, characterized in that: It includes an annular shielding component, a lifting component, a wafer carrier and a driving component. The lifting component is used to drive the annular shielding component to rise and fall so as to approach or move away from the wafer arranged on the wafer carrier from the back. The wafer carrier is suitable for adsorbing the wafer. The wafer carrier and the lifting component are arranged on the driving component, so that the driving component drives the wafer carrier and the lifting component to rotate synchronously, and at the same time, the lifting component drives the annular shielding component to rotate synchronously.

2. The developer backflow prevention device according to claim 1, characterized in that: The annular shielding component is provided with a plurality of air holes at intervals, the air holes are suitable for blowing out airflow, and the air holes face the outside of the annular shielding component.

3. The developer backflow prevention device according to claim 2, characterized in that: The air hole is inclined upward toward the outside of the annular shielding assembly, and the angle between the direction of the air flow ejected from the air hole and the central axis of the annular shielding assembly is 10°~80°.

4. The developer backflow prevention device according to claim 2, characterized in that: The annular shielding component has an annular air cavity therein, and each of the air holes is connected to the annular air cavity. The annular shielding component also includes a gas pipeline, and the gas pipeline is connected to an external gas source and the annular air cavity.

5. The device for preventing developer backflow according to any one of claims 1 to 4, characterized in that: The annular shielding assembly comprises an annular shielding ring and an elastic sealing ring wrapped outside the annular shielding ring.

6. The developer backflow prevention device according to claim 5, characterized in that: It also includes a back wash component, which is suitable for spraying cleaning liquid to clean the back side of the wafer on the wafer carrier. The back wash component includes a plurality of nozzles, each of which is arranged on the driving component, so that each of the nozzles rotates synchronously with the wafer carrier.

7. The device for preventing developer backflow according to any one of claims 1 to 4, characterized in that: A pressure sensor is provided on the annular shielding component, and the pressure sensor is communicatively connected with the lifting component.

8. A method for developing a wafer, characterized in that: Includes steps: S10, placing a wafer to be developed on a wafer stage, keeping the wafer stage rotating and spraying a developing solution on the front side of the wafer; S20, reducing the rotation speed of the wafer stage, and moving the annular shielding component that rotates synchronously with the wafer stage upward so that it contacts the back side of the wafer; S30, stopping spraying the developer, reducing the rotation speed of the wafer stage, and entering the development stage; S40, after the development is completed, the annular shielding assembly is moved downward to be away from the back side of the wafer, and then a cleaning liquid is sprayed on the back side of the wafer for back washing.

9. The wafer developing method according to claim 8, characterized in that: In step S30, after reducing the rotation speed of the wafer stage, an air flow is sprayed toward the edge of the wafer through the air holes on the annular shielding assembly, thereby forming an annular shielding air flow on the back side of the wafer, and after the development is completed, the air flow is turned off; In step S20, when the pressure sensor on the annular shielding assembly detects that the pressure between the annular shielding assembly and the back side of the wafer exceeds a preset value, the upward movement of the annular shielding assembly is stopped.

Images