Monolithic wet etch system and method of operation
By introducing a liquid distribution tank and a rotating mechanism into the wet etching system, the problem of uneven spraying of the etching solution was solved, achieving uniform etching of the wafer and efficient recovery of the etching solution, thus improving the etching effect and resource utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- YIYI SEMICON TECH (WUXI) CO LTD
- Filing Date
- 2022-08-12
- Publication Date
- 2026-05-22
AI Technical Summary
In existing wet etching systems, uneven spraying of the etching solution onto the wafer leads to inconsistent etching uniformity and causes etching damage. At the same time, the limited recycling methods for the etching solution result in waste and secondary etching contamination.
The single-piece wet etching system uses multiple inwardly recessed dispensing tanks and nozzles on the pressed part, combined with a rotating mechanism and a lifting mechanism, to achieve uniform spreading and rapid coverage of the etching solution, and is equipped with a recycling system to reuse the etching solution.
It achieves uniform spraying of etching solution on wafers, shortens spraying time, reduces etching damage, and improves the utilization rate of etching solution through a recycling system, avoiding waste and secondary etching pollution.
Smart Images
Figure CN115188693B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wafer etching technology, and in particular to a single-wafer wet etching system and operating method. Background Technology
[0002] like Figure 1 As shown, the existing wet etching system includes a wafer carrier component 1, an etching solution supply system 2, and a controller 3. The wafer carrier component 1 includes a wafer carrier stage 11, a support base 12, and a rotation mechanism. The wafer carrier stage 11 fixes the wafer 7 by negative pressure adsorption or by clamps. The support base 12 supports the wafer carrier stage 11 and drives the wafer carrier stage 11 to rotate through the rotation mechanism. The etching solution supply system 2 includes a nozzle 21, an etching solution supply source 22, and a control valve 23. The nozzle 21, the control valve 23, and the etching solution supply source 22 are connected by pipes. The control valve 23 is connected to the controller 3. The controller 3 can control the opening and closing of the control valve 23, thereby controlling the etching solution 8 in the etching solution supply source 22 to start or stop spraying the etching solution 8 onto the wafer 7 through the nozzle 21.
[0003] like Figure 2 As shown, when the etching solution 8 is spread evenly on the entire surface of the wafer 7 to be etched, it takes too much time and increases the amount of etching solution 8 used; in the existing wet etching system, the etching solution 8 is not evenly sprayed on the wafer 7, causing different etching uniformities at different locations on the wafer 7, resulting in etching damage; the system has a single recycling method, which uses centrifugal force to throw off the residual liquid on the wafer 7, which wastes the etching solution 8, and the residual liquid that is not thrown off may cause secondary etching or other contamination on the surface of the wafer 7. Summary of the Invention
[0004] The purpose of this invention is to provide a single-wafer wet etching system and operating method to solve the technical problem in existing wet etching systems where the etching solution is unevenly sprayed onto the wafer, causing different etching uniformities at different locations on the wafer and resulting in etching damage. The various technical effects of the preferred solutions among the many technical solutions provided by this invention are detailed below.
[0005] To achieve the above objectives, the present invention provides the following technical solution:
[0006] The present invention provides a single-wafer wet etching system, comprising a wafer carrier, an etching solution supply system, a controller, a pressing component, and a lifting mechanism. The pressing component is located above the wafer carrier, the lifting mechanism is connected to the pressing component, the lifting mechanism is connected to the controller, and the controller can control the lifting mechanism to push the pressing component to move towards or away from the wafer carrier. The etching solution supply system is connected to the controller.
[0007] The pressing component has a mounting hole in the middle, and the nozzle of the etching solution supply system is disposed in the mounting hole. The surface of the pressing component has an inwardly recessed liquid distribution groove, which is connected to the mounting hole. There are multiple liquid distribution grooves, and all the liquid distribution grooves are distributed along the circumferential direction of the mounting hole.
[0008] Optionally, the surface of the pressing component is provided with outwardly protruding stirring blocks, and the number of stirring blocks is multiple.
[0009] Optionally, the pressing component has a disc-shaped structure.
[0010] Optionally, the diameter of the pressing element is greater than or equal to the diameter of the wafer.
[0011] Optionally, the system also includes a recycling system, which includes a suction nozzle, a recycling tank, a pump body, and a valve body. The suction nozzle is connected to the recycling tank via a suction pipe, and the recycling tank is connected to the etching solution supply system via a discharge pipe. The pump body is mounted on the suction pipe, and the valve body is mounted on the discharge pipe. Both the pump body and the valve body are connected to the controller, and the suction nozzle is mounted on the pressing component.
[0012] Optionally, the pressing component is provided with a plurality of mating holes, the number of suction nozzles is the same as the number of mating holes, the suction nozzles are disposed in the mating holes, and all the mating holes are distributed along the circumferential direction of the mounting hole.
[0013] Optionally, the etching solution supply system includes an etching solution supply source and a control valve. The etching solution supply source and the control valve are connected through a first pipe, the control valve and the nozzle are connected through a second pipe, the liquid outlet pipe is connected to the second pipe, and the control valve is connected to the controller.
[0014] Optionally, the wafer carrier component includes a wafer carrier stage, a support base, and a rotation mechanism. The rotation mechanism is disposed on the support base, the wafer carrier stage is located on the support base and is connected to the rotation mechanism, the rotation mechanism can drive the wafer carrier stage to rotate, and the wafer carrier stage is used to carry the wafer.
[0015] Optionally, the lifting mechanism is an electric push rod mechanism.
[0016] The present invention provides an operating method for a single-wafer wet etching system, comprising the following steps:
[0017] Step A: First, fix the wafer on the wafer carrier stage, and then control the lifting mechanism through the controller to push the pressing component to move closer to the wafer until the pressing component moves to the designated position. Then, the controller controls the lifting mechanism to stop moving.
[0018] Step B: The controller controls the control valve to open, and the etching solution in the etching solution supply source is sprayed out through the nozzle. The etching solution is guided onto the wafer under the action of the pressing component. Then, the rotating mechanism drives the wafer carrier to rotate at a set first speed, and the wafer carrier drives the wafer to rotate. During the rotation of the wafer, the stirring block on the pressing component can make the etching solution spread evenly on the wafer.
[0019] Step C: After the etching solution is evenly spread on the wafer, the controller controls the control valve to close, and the etching solution etches the wafer within a set time.
[0020] Step D: After etching is completed, the controller controls the pump to start, and at the same time the rotating mechanism drives the wafer carrier to rotate at a set second speed. The suction nozzle will suck the etching solution on the wafer into the recycling tank.
[0021] Step F: After the etching solution on the wafer is recovered, the controller controls the lifting mechanism to push the pressing component away from the wafer, and at the same time the rotating mechanism stops rotating, removes the wafer, and checks the etching effect of the wafer. If the etching effect of the wafer does not meet the expectations, continue to repeat steps A to F; if the etching effect of the wafer meets the expectations, the etching is completed.
[0022] This invention provides a single-wafer wet etching system in which the nozzle of the etching solution supply system is positioned in the middle of a pressing component. The pressing component has inwardly recessed distribution channels on its surface, facing the wafer. Multiple distribution channels are distributed circumferentially along the mounting holes. During operation, the pressing component needs to be moved to a designated position, creating a gap between the pressing component and the wafer. Therefore, when the nozzle sprays etching solution onto the wafer, the restriction of the space above the wafer by the pressing component prevents the etching solution from accumulating in the center of the wafer. Instead, the etching solution is dispersed under the pressure of the pressing component. Furthermore, some etching solution flows into the distribution channels and from there to the periphery of the wafer. Simultaneously, the rotation of the wafer allows the etching solution to quickly cover the wafer, thus shortening the spraying time and ensuring uniform coverage of the wafer. This solves the technical problem in existing wet etching systems where uneven spraying of etching solution onto the wafer causes different etching uniformities and leads to etching damage. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of the structure of a wet etching system in the prior art;
[0025] Figure 2 This is a schematic diagram of etching using a wet etching system in the prior art;
[0026] Figure 3 This is a schematic diagram of the structure of the single-wafer wet etching system provided in an embodiment of the present invention;
[0027] Figure 4 This is a top view of the pressed component of the single-piece wet etching system provided in an embodiment of the present invention;
[0028] Figure 5 This is a schematic diagram of the structure at the start of liquid spraying in the operation method of the single-piece wet etching system provided in the embodiment of the present invention;
[0029] Figure 6 This is a schematic diagram of the structure in which the etching solution is uniformly spread on the wafer in the operation method of the single-wafer wet etching system provided in the embodiment of the present invention;
[0030] Figure 7 This is a schematic diagram of the structure for recovering etching solution in the operation method of the single-piece wet etching system provided in this embodiment of the invention;
[0031] In the figure: 1. Wafer carrier component; 11. Wafer carrier stage; 12. Support base; 2. Etching solution supply system; 21. Nozzle; 22. Etching solution supply source; 23. Control valve; 3. Controller; 4. Pressing component; 41. Mounting hole; 42. Dispensing tank; 43. Stirring block; 44. Mating hole; 5. Lifting mechanism; 6. Recovery system; 61. Suction nozzle; 62. Recovery tank; 63. Pump body; 64. Valve body; 7. Wafer; 8. Etching solution. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.
[0033] In the description of this invention, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0034] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0035] Example 1:
[0036] This invention provides a single-wafer wet etching system, including a wafer carrier 1, an etching solution supply system 2, a controller 3, a pressing component 4, and a lifting mechanism 5. The pressing component 4 is located above the wafer carrier 1, and the wafer 7 can be placed on the wafer carrier 1 and the wafer carrier 1 can push the wafer 7 to rotate. The lifting mechanism 5 is connected to the pressing component 4 and is connected to the controller 3. The controller 3 can control the lifting mechanism 5 to push the pressing component 4 to move closer to or away from the wafer carrier 1. The etching solution supply system 2 is connected to the controller 3.
[0037] The pressing component 4 has a mounting hole 41 in the middle. The nozzle 21 on the etching solution supply system 2 is located in the mounting hole 41 and is perpendicular to the wafer 7. The surface of the pressing component 4 has an inwardly recessed liquid distribution groove 42. The length direction of the liquid distribution groove 42 is consistent with the radial direction of the pressing component 4. The liquid distribution groove 42 is connected to the mounting hole 41. There are multiple liquid distribution grooves 42, and all liquid distribution grooves 42 are distributed along the circumferential direction of the mounting hole 41. This invention provides a single-wafer wet etching system in which the nozzle 21 of the etching solution supply system 2 is positioned in the middle of the pressing component 4. The pressing component 4 has inwardly recessed dispensing grooves 42 facing the wafer. Multiple dispensing grooves 42 are distributed along the circumferential direction of the mounting holes 41. During operation, the pressing component 4 needs to be moved to a designated position to create a gap between the pressing component 4 and the wafer 7. Therefore, when the nozzle 21 sprays etching solution 8 onto the wafer 7, the restriction of the space above the wafer 7 by the pressing component 4 prevents the etching solution 8 from being concentrated in the middle of the wafer 7. Instead of accumulating, the etching solution 8 is dispersed under the pressure of the pressing component. When the nozzle 21 sprays the etching solution 8, some of the etching solution 8 flows to the distribution tank 42 and from the distribution tank 42 to the periphery of the wafer 7. At the same time, as the wafer 7 rotates, the etching solution 8 quickly covers the wafer 7, thereby shortening the spraying time and ensuring that the etching solution 8 is evenly spread on the wafer 7. This solves the technical problem in the existing wet etching system where the etching solution is unevenly sprayed on the wafer, causing different etching uniformities at different locations on the wafer and resulting in etching damage.
[0038] As an optional implementation, the surface of the pressing component 4 is provided with outwardly protruding stirring blocks 43. Multiple stirring blocks 43 are distributed on the surface of the pressing component 4, facing the wafer 7. During the rotation of the wafer 7, the stirring blocks 43 disperse the etchant 8 accumulated on the wafer 7, thereby uniformly dispersing the etchant 8 on the wafer 7. The stirring blocks 43 are distributed along a curved direction, allowing each stirring block 43 to stir a specific area of the wafer 7.
[0039] As an optional implementation, the pressing component 4 has a disk-shaped structure, and the diameter of the pressing component 4 is greater than or equal to the diameter of the wafer 7. This is so that the pressing component 4 covers the wafer 7, thereby allowing the wafer 7 to be fully covered with the etching solution 8.
[0040] As an optional implementation, a recycling system 6 is also included. The recycling system 6 can recycle the etching solution 8 on the wafer 7 and can reuse the etching solution 8. The recycling system 6 includes a suction nozzle 61, a recycling tank 62, a pump body 63, and a valve body 64. The suction nozzle 61 is connected to the recycling tank 62 through a suction pipe. The recycling tank 62 is connected to the etching solution supply system 2 through an outlet pipe. The pump body 63 is installed on the suction pipe, and the valve body 64 is installed on the outlet pipe. Both the pump body 63 and the valve body 64 are connected to the controller 3. The suction nozzle 61 is installed on the pressing component 4. When recovering the etching solution 8, the controller 3 controls the pump body 63 to open, so that the suction nozzle 61 can suck the etching solution 8 on the wafer 7 into the suction pipe, and then into the recovery tank 62. While the suction nozzle 61 is recovering the etching solution 8 on the wafer 7, the wafer 7 rotates under the movement of the wafer support component 1, so that the etching solution 8 on all parts of the wafer 7 is below the suction nozzle 61, facilitating rapid recovery. Simultaneously, the wafer 7 rotates at a very low speed, firstly to prevent the etching solution 8 from being thrown out, and secondly to provide the suction nozzle 61 with recovery time. When the controller 3 controls the valve body 64 to open, the etching solution 8 in the recovery tank 62 can enter the nozzle 21 through the outlet pipe and be sprayed onto the wafer 7 from the nozzle 21, achieving the recovery and reuse of the etching solution 8.
[0041] As an optional implementation, the pressing component 4 is provided with a plurality of mating holes 44, and the number of suction nozzles 61 is the same as the number of mating holes 44. The suction nozzles 61 are disposed in the mating holes 44, and all mating holes 44 are distributed along the circumferential direction of the mounting holes 41. The plurality of suction nozzles 61 are connected to the recovery tank 62 through suction pipes. The plurality of suction nozzles 61 can work simultaneously, and can quickly recover the etching solution 8 on the wafer 7.
[0042] As an optional implementation, the etching solution supply system 2 includes an etching solution supply source 22 and a control valve 23. The etching solution supply source 22 is used to hold the etching solution 8. The etching solution supply source 22 and the control valve 23 are connected through a first pipe. The control valve 23 is connected to the nozzle 21 through a second pipe. One end of the liquid outlet pipe is connected to the second pipe, and the other end of the liquid outlet pipe is connected to the recovery tank 62. The control valve 23 is connected to the controller 3, which can control the opening and closing of the control valve 23.
[0043] As an optional implementation, the wafer carrier component 1 includes a wafer carrier stage 11, a support base 12, and a rotation mechanism. The rotation mechanism is disposed on the support base 12, the wafer carrier stage 11 is located on the support base 12 and is connected to the rotation mechanism, and the rotation mechanism can drive the wafer carrier stage 11 to rotate. The wafer carrier stage 11 is used to carry the wafer 7.
[0044] As an optional implementation, the lifting mechanism 5 can be an electric push rod mechanism.
[0045] Example 2:
[0046] This invention provides an operation method for a single-wafer wet etching system, comprising the following steps:
[0047] Step A: First, fix the wafer 7 on the wafer carrier stage 11, and then control the lifting mechanism 5 through the controller 3 to push the pressing component 4 to move closer to the wafer 7 until the pressing component 4 moves to the designated position, and then control the lifting mechanism 5 to stop moving.
[0048] Step B: The controller 3 controls the control valve 23 to open, and the etching solution 8 in the etching solution supply source 22 is sprayed out through the nozzle 21. Under the action of the pressing component 4, the etching solution 8 is guided onto the wafer 7. Then, the rotating mechanism drives the wafer carrier stage 11 to rotate at a set first speed, and the wafer carrier stage 11 drives the wafer 7 to rotate. During the rotation of the wafer 7, the stirring block 43 on the pressing component 4 can make the etching solution 8 spread evenly on the wafer 7.
[0049] Step C: After the etching solution 8 is evenly spread on the wafer 7, the controller 3 controls the control valve 23 to close, and the etching solution 8 etches the wafer 7 within a set time.
[0050] Step D: After etching is completed, the controller 3 controls the pump body 63 to turn on, and at the same time the rotating mechanism drives the wafer carrier stage 11 to rotate at the set second speed. At this time, the second speed is relatively low, and the suction nozzle 61 will suck the etching solution 8 on the wafer 7 into the recycling tank 62. The etching solution 8 in the recycling tank 62 can be retained for the next use.
[0051] Step F: After the etching solution 8 on wafer 7 is recovered, controller 3 controls lifting mechanism 5 to push pressing component 4 away from wafer 7. At the same time, rotating mechanism stops rotating, wafer 7 is removed, and the etching effect of wafer 7 is checked. If the etching effect of wafer 7 does not meet the expected effect, continue to repeat steps A to F; if the etching effect of wafer 7 meets the expected effect, the etching is completed.
[0052] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A single-wafer wet etching system, characterized in that, It includes a wafer carrier component (1), an etching solution supply system (2), a controller (3), a pressing component (4), and a lifting mechanism (5), wherein, The pressing component (4) is located above the wafer carrier component (1), the lifting mechanism (5) is connected to the pressing component (4), the lifting mechanism (5) is connected to the controller (3) and the controller (3) can control the lifting mechanism (5) to push the pressing component (4) to move closer to or away from the wafer carrier component (1), and the etching solution supply system (2) is connected to the controller (3); The pressing component (4) has a mounting hole (41) in the middle. The nozzle (21) on the etching solution supply system (2) is located in the mounting hole (41). The pressing component (4) has an inwardly recessed liquid distribution groove (42) on its surface. The liquid distribution groove (42) is connected to the mounting hole (41). There are multiple liquid distribution grooves (42), and all the liquid distribution grooves (42) are distributed along the circumferential direction of the mounting hole (41). The surface of the pressing component (4) is provided with outwardly protruding stirring blocks (43), and there are multiple stirring blocks (43).
2. The single-wafer wet etching system according to claim 1, characterized in that, The pressing component (4) has a disc-shaped structure.
3. The single-wafer wet etching system according to claim 2, characterized in that, The diameter of the pressing element (4) is greater than or equal to the diameter of the wafer (7).
4. The single-wafer wet etching system according to claim 1, characterized in that, It also includes a recycling system (6), which includes a suction nozzle (61), a recycling tank (62), a pump body (63), and a valve body (64). The suction nozzle (61) is connected to the recycling tank (62) through a suction pipe, and the recycling tank (62) is connected to the etching solution supply system (2) through a discharge pipe. The pump body (63) is installed on the suction pipe, and the valve body (64) is installed on the discharge pipe. Both the pump body (63) and the valve body (64) are connected to the controller (3). The suction nozzle (61) is installed on the pressing component (4).
5. The single-wafer wet etching system according to claim 4, characterized in that, The pressing component (4) is provided with a plurality of mating holes (44), the number of suction nozzles (61) is the same as the number of mating holes (44), the suction nozzles (61) are disposed in the mating holes (44), and all the mating holes (44) are distributed along the circumferential direction of the mounting hole (41).
6. The single-wafer wet etching system according to claim 4, characterized in that, The etching solution supply system (2) includes an etching solution supply source (22) and a control valve (23). The etching solution supply source (22) and the control valve (23) are connected through a first pipe. The control valve (23) and the nozzle (21) are connected through a second pipe. The liquid outlet pipe is connected to the second pipe. The control valve (23) is connected to the controller (3).
7. The single-wafer wet etching system according to claim 1, characterized in that, The wafer carrier component (1) includes a wafer carrier stage (11), a support base (12), and a rotation mechanism. The rotation mechanism is disposed on the support base (12). The wafer carrier stage (11) is located on the support base (12) and is connected to the rotation mechanism. The rotation mechanism can drive the wafer carrier stage (11) to rotate. The wafer carrier stage (11) is used to carry the wafer (7).
8. The single-wafer wet etching system according to claim 1, characterized in that, The lifting mechanism (5) is an electric push rod mechanism.
9. An operation method for a single-wafer wet etching system, characterized in that, Includes the following steps: Step A: First, fix the wafer (7) on the wafer carrier stage (11), and then control the lifting mechanism (5) through the controller (3) to push the pressing component (4) to move closer to the wafer (7) until the pressing component (4) moves to the designated position, and then control the lifting mechanism (5) to stop moving. Step B: The controller (3) controls the control valve (23) to open, and the etching solution (8) in the etching solution supply source (22) is sprayed out through the nozzle (21). The etching solution (8) is guided onto the wafer (7) under the action of the pressing component (4). Then, the rotating mechanism drives the wafer carrier stage (11) to rotate at a set first speed, and the wafer carrier stage (11) drives the wafer (7) to rotate. During the rotation of the wafer (7), the stirring block (43) on the pressing component (4) can make the etching solution (8) spread evenly on the wafer (7). Step C: After the etching solution (8) is evenly spread on the wafer (7), the controller (3) controls the control valve (23) to close, and the etching solution (8) etches the wafer (7) within a set time. Step D: After etching is completed, the controller (3) controls the pump body (63) to turn on, and at the same time the rotating mechanism drives the wafer carrier stage (11) to rotate at the set second speed. The suction nozzle (61) will suck the etching solution (8) on the wafer (7) into the recycling tank (62). Step F: After the etching solution (8) on the wafer (7) is recovered, the controller (3) controls the lifting mechanism (5) to push the pressing component (4) away from the wafer (7), and at the same time the rotating mechanism stops rotating, removes the wafer (7), and checks the etching effect of the wafer (7). If the etching effect of the wafer (7) does not meet the expected effect, continue to repeat steps A to F; if the etching effect of the wafer (7) meets the expected effect, then the etching is completed.