BOE etching device with uniform etching
By employing a flow equalization plate to disperse the etching fluid flow field and adjust the silicon wafer position in the BOE etching apparatus, the problem of etching non-uniformity was solved, thereby improving the uniformity and quality of silicon wafer etching.
Patent Information
- Application Number
- CN202423002174.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-12-05
AI Technical Summary
The existing BOE etching process has difficulty ensuring etching uniformity when etching silicon wafers with different pattern densities, resulting in uneven etching rate and etching profile, which affects the overall etching quality of the silicon wafer.
A BOE etching apparatus with uniform etching was designed, including a tank and a clamping mechanism. The tank consists of an outer tank and an inner tank. A flow equalization plate is installed at the bottom of the inner tank to disperse the etching liquid flow field. The clamping mechanism ensures that the silicon wafer maintains a stable position and angle during the etching process through adjustable boom components and fixtures.
By uniformly dispersing the etching fluid flow field and adjusting the position of the silicon wafer, the uniformity and quality of silicon wafer etching are improved, ensuring the stability and consistency of the etching process.
Smart Images
Figure CN223462202U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of semiconductor cleaning process, concretely to a BOE etching device of etching uniformity. BACKGROUND
[0002] In the semiconductor cleaning process, there are various wafer cleaning and etching processes, and different wet processes need to be used for different wafer products. In the related manufacturing process, a variety of different wet cleaning and etching processes need to be matched. Among them, the silicon dioxide wet etching process of BOE (Buffer of Etch) is widely used in the wet manufacturing process of semiconductor wafers.
[0003] The difficulty of BOE etching lies in ensuring uniformity in the etching process on silicon wafers with different pattern densities, such as silicon wafer regions with dense patterns, large pattern intervals, and high aspect ratio patterns. In the etching process, some problems of etching uniformity are mainly caused by the fact that the etching rate and etching profile are related to the pattern size and density, which is a parameter for measuring the etching capability of the etching process on the whole wafer, or the whole batch, or batch to batch. With the increasing demand for etching, the uniformity of BOE etching is difficult to guarantee, and it is difficult to make BOE etching reach the best etching state. SUMMARY
[0004] In order to overcome the shortcomings of the prior art, the utility model provides a BOE etching device of etching uniformity, which can effectively solve the technical problem of insufficient uniformity during silicon wafer etching.
[0005] The utility model solves the technical problems by adopting the following technical scheme:
[0006] A BOE etching device of etching uniformity, comprising a groove body and a clamping mechanism, the clamping mechanism is used for sending silicon wafers to the groove body for etching, the groove body comprises an outer groove and an inner groove, the outer groove and the inner groove are provided with through holes, the bottom of the inner groove is provided with a flow uniform plate fixed in the air through a support, the flow uniform plate is arranged above the through hole, the flow uniform plate is provided with a plurality of flow holes, the flow uniform plate is provided with a limiting block for limiting, the inner side of the limiting block is provided with an inclined surface, the clamping mechanism comprises a hanging arm and a jig for placing silicon wafers, the jig is connected with a plug-in limiting block fixed plug, one end of the jig connected with the hanging arm, the jig can be moved to the bottom of the inner groove and fixed through the limiting block, the end of the hanging arm away from the jig is connected with a swing motor for swinging the hanging arm, the hanging arm is also connected with an adjusting assembly for adjusting the inclination of the hanging arm, so that the plug is inclined and tightly attached to the inclined surface on one side.
[0007] Further, an injection pipe is installed outside the groove body for injecting BOE etching liquid into the outer groove.
[0008] Further, the top of the inner groove is lower than the plane where the top of the outer groove is located, and the top of the inner groove is also provided with a plurality of notch positions for flowing the BOE etching solution into the inner groove.
[0009] Further, the outer edge of the flow uniformizing plate is provided with a plurality of locking members for locking the inner groove.
[0010] Further, the number of the limiting blocks is four, and the limiting blocks are distributed at the edges of the four corners of the card, and the inclined surface is arranged at the side of the limiting block close to the card.
[0011] Further, the hanging arm member is provided with an adjusting hole, and the adjusting assembly is composed of a driving module and a plate block connected to the driving module and moving left and right, the plate block is close to one side of the hanging arm, and a movable member inserted into the adjusting hole and moving is arranged on the plate block, so that the hanging arm member is inclined to the moving direction of the movable member.
[0012] Further, the hanging arm member is composed of a first hanging arm and a second hanging arm which are detachably connected at one end, the jig is connected to one end of the first hanging arm away from the second hanging arm, and the swing motor is connected to one end of the second hanging arm away from the first hanging arm.
[0013] Compared with the prior art, the utility model has the advantages that:
[0014] The groove body provided by the utility model can effectively maintain the uniformity of the temperature and flow in the inner groove through the flow holes on the flow uniformizing plate after the BOE etching solution is injected, and the swingable jig can improve the state of uneven etching caused by the front surface of the silicon wafer, thereby improving the quality of the silicon wafer etching. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 It is a front direction schematic view of the overall structure of the embodiment of the utility model;
[0016] Figure 2 It is a top direction schematic view of the overall structure of the embodiment of the utility model;
[0017] Figure 3 It is a top direction schematic view of the overall structure of the embodiment of the utility model;
[0018] Figure 4 It is an explosion schematic view of the overall structure of the embodiment of the utility model;
[0019] Figure 5 It is the embodiment of the utility model Figure 4 A part structure enlarged schematic view of the embodiment of the utility model;
[0020] Figure 6 It is the embodiment of the utility model Figure 4 A part structure enlarged schematic view of the embodiment of the utility model;
[0021] Reference numerals in the drawings:
[0022] 1 - tank, 2 - clamping mechanism, 3 - support, 4 - flow equalizing plate, 5 - flow hole, 6 - limiting block, 7 - inclined surface, 8 - swing motor, 9 - adjusting assembly, 10 - injection pipe, 11 - locking piece, 12 - adjusting hole position, 13 - through hole, 14 - plug, 15 - pipeline;
[0023] 101 - outer groove, 102 - inner groove, 103 - notch position;
[0024] 201 - hanger arm, 202 - jig;
[0025] 901 - drive module, 902 - plate, 903 - movable piece. DETAILED DESCRIPTION
[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0027] As shown in the drawings, the present application provides a BOE etching device with uniform etching, which is mainly used for etching silicon wafer, and the specific structure mainly comprises a tank 1 and a clamping mechanism 2, wherein the tank 1 is mainly used for placing the BOE etching liquid used for etching silicon wafer, and the clamping mechanism 2 is used for sending the silicon wafer to the tank 1 for etching. The clamping mechanism 2 can cooperate with the external driving equipment to repeatedly deliver the silicon wafer into the tank 1 and take out the etched silicon wafer. Figures 1-6 The structure of the tank 1 is composed of an outer groove 101 and an inner groove 102. When the BOE etching liquid is injected, it is mainly injected into the inner part of the outer groove 101, and then the BOE etching liquid in the outer groove 101 flows into the inner groove 102 from the through hole 13. When the BOE etching liquid is injected, the injection pipe 10 for injecting the BOE etching liquid is installed on the outer side of the tank 1. The branch of the injection pipe 10 can be provided with a plurality of injection pipes, which can simultaneously inject the BOE etching liquid from different positions in the outer groove 101.
[0028]
[0029] When the BOE flows from the outer tank 101 into the inner tank 102, it flows in through the bottom conductive through hole 13, the through hole 13 is provided with multiple and distributed on the pipeline 15, the through hole 13 is dispersed in different positions of the pipeline 15, the direction of the through hole 13 is not upward. However, it should be noted that the position of the through hole 13 is not aligned with the position of the injection pipe 10 for injecting the BOE etching solution, so as to avoid the flow rate of the BOE etching solution into the inner tank 102 being too large to affect the later etching of the silicon wafer. In addition, if the flow rate of the BOE etching solution injected into the outer tank 101 is too large, the water level of the BOE etching solution will rise in the outer tank 101. In order to prevent the BOE etching solution from overflowing, the BOE etching solution can also flow into the inner tank 102 through the top of the inner tank 102. At this time, the height of the inner tank 102 should be less than the height of the outer tank 101, and multiple notches 103 for flowing the BOE etching solution into the inner tank 102 are also provided on the top of the inner tank 102, which effectively prevents the BOE etching solution from overflowing.
[0030] After the etching solution BOE flows into the inner tank 102, a flow uniformizing plate 4 is installed at the bottom of the inner tank 102. When the flow uniformizing plate 4 is installed, a gap is left between the four sides of the flow uniformizing plate 4 and the inner side of the inner tank 102, and the flow uniformizing plate 4 is supported in a suspended state by the support member 3 locked around the four sides and the bottom of the inner tank 102. It should be noted that the height of the flow uniformizing plate 4 after being fixed should be above the through hole 13. In addition, multiple locking members 11 are also installed on the outer edge of the flow uniformizing plate 4 and locked with the inner tank 102, which further enhances the fixation.
[0031] In order to disperse the liquid flow field during etching in the inner tank 102, multiple flow holes 5 are provided on the flow uniformizing plate 4, which are conductive and uniformly distributed, so that the BOE etching solution in the inner tank 102 flows out from the flow holes 5 upward, which can maintain the etching property of the BOE etching solution temperature and flow rate during etching in the inner tank, and improve the quality of silicon wafer etching.
[0032] When etching the silicon wafer, the silicon wafer is clamped by the clamping mechanism 2 and placed in the inner tank 102 for etching. The clamping mechanism 2 is composed of a hanging arm member 201 and a jig 202, wherein the silicon wafer is placed in the jig 202 and held by the hanging arm member 201 connected to one end.
[0033] When the silicon wafer is placed in the jig 202, the hanging arm member 201 extends to the bottom of the inner tank 102 and is limited and fixed by the limiting block 6 on the flow uniformizing plate 4. In order to facilitate fixation and improve the quality of etching, a plug 14 is connected to the bottom of the jig 202, and the plug 14 is fixed in the limiting block 6.
[0034] The number of limiting blocks 6 fixed with the same plug 14 is four, which are distributed at the four corner edges of the plug 14 and fixed, so as to ensure that the silicon wafer does not move during etching. In order to facilitate the later fixation of the inclined movement of the jig 202, an inclined surface 7 is provided on the inner side of the limiting block 6 to avoid the movement of the jig 202 during etching.
[0035] In addition, the silicon wafer needs to be adjusted to a certain angle when etching in the BOE etching solution. The technology provided by the present solution can control the cantilever 201 by adjusting the adjusting assembly 9 to tilt the jig 202 by 8 degrees towards the back of the silicon wafer. At this time, one end of the jig is in close contact with the limiting block 6 and abuts against the inclined surface 7 on the limiting block 6, and the other end of the jig is open to form an opening of 8 degrees, effectively ensuring that the etching surface is directed. The end of the cantilever 201 away from the jig 202 is connected with a swing motor 8 that can freely swing the cantilever 201, facilitating the swinging of the cantilever 201.
[0036] In order to better control the movement of the cantilever 201 to both sides, the adjusting hole 12 is provided on the cantilever 201, and the adjusting hole 12 is in the shape of an elongated strip along the direction in which the cantilever 201 extends. The adjusting assembly 9 for controlling the cantilever 201 is composed of a driving module 901 and a plate 902 connected to the driving module 901 for moving left and right, wherein the plate 902 is close to one side of the cantilever and is provided with a movable part 903 inserted into the adjusting hole 12 for moving, so that the cantilever 201 is tilted in the direction of movement of the movable part 903. When the plate 902 moves, the movable part 903 moves to different positions in the adjusting hole 12, finally causing the cantilever 201 to tilt synchronously with the jig 202.
[0037] In order to facilitate user operation and replace the jig 202 for the next round of etching processing of the silicon wafer, the cantilever 201 is composed of a first cantilever 2011 and a second cantilever 2012 connected at one end, the jig 202 is connected to the end of the first cantilever 2011 away from the second cantilever 2012, and the swing motor 8 is connected to the end of the second cantilever 2012 away from the first cantilever 2011. The user can directly disassemble the first cantilever 2011 to replace a new first cantilever 2011 and the jig 202 loaded with the silicon wafer.
[0038] It should be noted that the present technology can also be combined with a lifting module for controlling the lifting of the clamping mechanism 2 to move the jig 202 out of the inner groove 102. When the lifting module is installed, it is connected to the bottom of the swing motor 8, but at the same time needs to be fixed in position synchronously with the adjusting assembly 9, so that the adjusting assembly 9 and the swing motor 8 are lifted synchronously.
[0039] In use, the jig 202 is placed in the inner groove 102 to be initially placed horizontally, and the plug 14 is fixed in the limiting block 6. Then, the jig 202 is tilted by 8 degrees towards the back of the silicon wafer, and the chemical etching process of the back of the silicon wafer begins. After the etching is completed, the jig 202 is reset to the horizontal position, the jig 202 is carried out of the inner groove 102, and the BOE etching process is completed.
[0040] Compared with the prior art, the groove body 1 provided by the technical scheme can effectively keep the temperature and flow uniformity in the inner groove 102 after injecting the BOE etching liquid through the flow holes 5 on the flow plate 4, and meanwhile, the swingable jig can improve the state of uneven etching caused by the front side contact of the silicon wafer, and improve the etching quality of the silicon wafer.
[0041] It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application, and any reference signs in the claims should not be regarded as limiting the claims involved.
Claims
1. A BOE etching device with uniform etching, comprising a tank body and a clamping mechanism, the clamping mechanism is used to send a silicon wafer to the tank body for etching, characterized in that: The groove body comprises an outer groove and an inner groove, the outer groove and the inner groove are provided with through holes, the bottom of the inner groove is provided with a flow-equalizing plate which is fixed in the air by a support, the flow-equalizing plate is arranged above the through hole, the flow-equalizing plate is provided with a plurality of flow holes, the flow-equalizing plate is provided with limiting blocks for limiting, the inner side of the limiting block is provided with an inclined surface, the clamping mechanism comprises a hanging arm and a jig for placing a silicon wafer, the bottom of the jig is connected with a plug which is fixed in the limiting block, one end of the jig is connected with the hanging arm, the jig can be moved to the bottom of the inner groove and fixed by the limiting block, the end of the hanging arm away from the jig is connected with an oscillating motor for oscillating the hanging arm, the hanging arm is further connected with an adjusting assembly for adjusting the inclination of the hanging arm, so that the plug is tightly attached to the inclined surface after being inclined. 2. The BOE etching device with uniform etching according to claim 1, wherein: The outer side of the groove body is provided with an injection pipe for injecting BOE etching liquid into the outer groove. 3.The BOE etching device with uniform etching according to claim 1, wherein: The top of the inner groove is lower than the plane where the top of the outer groove is located, and the top of the inner groove is further provided with a plurality of notches for flowing BOE etching liquid into the inner groove. 4.The BOE etching device with uniform etching according to claim 1, wherein: The outer edge of the flow-equalizing plate is provided with a plurality of locking members which are locked with the inner groove.
5. The BOE etching device with uniform etching according to claim 1, wherein: The number of limiting blocks is four, and they are distributed at the four corners of the plug, and the inclined surface is arranged on the side of the limiting block which is tightly attached to the plug. 6.The BOE etching device with uniform etching according to claim 1, wherein: The hanging arm is provided with an adjusting hole, the adjusting assembly comprises a driving module and a plate which moves left and right, the plate is close to one side of the hanging arm, and is provided with a movable member which is inserted into the adjusting hole and moves, so that the hanging arm is inclined in the direction of moving towards the movable member.
7. The etching device of any one of claims 1-6, wherein the etching device is a BOE etching device. The hanging arm comprises a first hanging arm and a second hanging arm which are detachably connected at one end, the jig is connected to the end of the first hanging arm away from the second hanging arm, and the oscillating motor is connected to the end of the second hanging arm away from the first hanging arm.