Tank wet etching device

Abstract

A tank-type wet etching device comprises: a process tank, at least one acid supply tank, a connecting pipe and a supporting component, wherein the position of the process tank is lower than that of the acid supply tank, the acid supply tank is connected to the process tank through a connecting pipe, the connecting pipe at least comprises a connected transverse pipe and a longitudinal pipe, the inlet end of the transverse pipe is connected to the acid supply tank, the outlet end of the longitudinal pipe is connected to the process tank, the acid supply tank is used to store acid and supply the stored acid to the process tank through the connecting pipe, the process tank is used to dilute the acid supplied by the acid supply tank or mix multiple supplied acid solutions to perform an etching process; the supporting component is in contact with the transverse pipe, and is used to keep the transverse pipe horizontal. The tank-type wet etching device of the present invention ensures that the acid concentration can remain stable after each acid change.

Description

Technical Field

[0001] The invention relates to the field of semiconductors, and in particular to a trench type wet etching device. Background Art

[0002] The etching process is a process of selectively corroding or stripping the surface of a semiconductor substrate or a thin film covering the surface according to the mask pattern or design requirements. The etching process is not only a basic manufacturing process for semiconductor devices and integrated circuits, but is also used in the processing of thin-film circuits, printed circuits and other fine patterns.

[0003] At present, there are two main etching methods: wet etching and dry plasma etching. In wet etching, the etchant is a liquid chemical mixture that reacts chemically with the wafer substrate to produce soluble substances, which then dissolve in the solution. For example, a solution containing hydrofluoric acid is used to etch silicon dioxide film, and phosphoric acid is used to etch aluminum film. As the main equipment for wet etching process, the tank wet etching equipment usually places the wafer in the acid tank or process tank of the tank etching equipment, and uses the etching solution or acid solution in the acid tank or process tank to immerse the wafer for a specific period of time, so that the unnecessary material layer on the wafer can be etched away.

[0004] In the prior art, acid liquid is usually supplied to an acid tank or a process tank through a special acid liquid supply device. Taking the formation of diluted hydrofluoric acid in the acid tank or the process tank as an example, a certain volume of undiluted hydrofluoric acid (for example, hydrofluoric acid with a molar concentration of 49%) is supplied into the acid tank or the process tank through an acid liquid supply tank, and a certain volume of pure water is supplied into the acid tank or the process tank through a pure water supply device. The two are mixed to form diluted hydrofluoric acid in the acid tank or the process tank.

[0005] However, the aforementioned method of forming diluted hydrofluoric acid in an acid tank or a process tank easily makes the concentration of the formed hydrofluoric acid too low or too high, which is not conducive to the etching process, and it is time-consuming and laborious to eliminate the concentration alarm. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to improve the accuracy of wafer warpage monitoring.

[0007] The present invention provides a tank-type wet etching device, comprising: a process tank, at least one acid liquid supply tank, connecting pipes and supporting components, wherein:

[0008] The position of the process tank is lower than that of the acid liquid supply tank, the acid liquid supply tank is connected to the process tank through a connecting pipe, the connecting pipe at least includes a connected transverse pipe and a longitudinal pipe, the inlet end of the transverse pipe is connected to the acid liquid supply tank, and the outlet end of the longitudinal pipe is connected to the process tank, the acid liquid supply tank is used to store acid liquid and supply the stored acid liquid to the process tank through the connecting pipe, and the process tank is used to dilute the acid liquid supplied by the acid liquid supply tank or mix multiple acid liquids supplied to perform an etching process;

[0009] The supporting member is in contact with the transverse pipe and is used to keep the transverse pipe horizontal.

[0010] Optionally, the transverse pipe includes an inlet end and an outlet end, and the longitudinal pipe includes an inlet end and an outlet end, the inlet end of the transverse pipe is connected to the acid supply tank, the outlet end of the transverse pipe is connected to the inlet end of the longitudinal pipe, the transverse pipe is inclined upward from the inlet end to the outlet end, and the supporting component is in contact with the transverse pipe, and the upward inclination angle of the transverse pipe is reduced by the supporting component, so that the transverse pipe remains horizontal.

[0011] Optionally, the top of the process tank has a top base, and the longitudinal pipe passes through the top base to flow process acid into the process tank.

[0012] Optionally, the supporting component is a supporting member, one end of which is fixedly connected to the transverse pipe, and the other end of which is fixedly connected to the top base.

[0013] Optionally, the supporting component is a suspension component, one end of the suspension component is fixedly connected to the transverse pipe, and the other end of the suspension component is fixedly connected to the outer wall of the acid supply tank.

[0014] Optionally, the distance between the position where the supporting component is fixed to the transverse pipeline and the acid supply tank is less than 1 / 2 of the total length of the transverse pipeline.

[0015] Optionally, the distance between the position where the supporting component is fixed to the transverse pipeline and the acid supply tank is 1 / 4-1 / 3 of the total length of the transverse pipeline.

[0016] Optionally, a control valve is provided between the acid supply tank and the transverse pipeline, and the control valve is used to control the on-off supply of acid from the acid supply tank to the process tank. The control valve is opened at the beginning of each acid change, and is closed at the end of the acid change. After the control valve is closed at the end of each acid change, the amount of acid remaining in the transverse pipeline is the same.

[0017] Optionally, it also includes a pure water supply end for supplying pure water to the process tank to dilute the acid solution in the process tank.

[0018] Optionally, the acid supplied by the acid supply tank is hydrofluoric acid, and the pure water dilutes the hydrofluoric acid supplied to the process tank.

[0019] Optionally, when the number of the acid liquid supply tanks is greater than or equal to two, the greater than or equal to two acid liquid supply tanks are connected to the process tank through different connecting pipes.

[0020] Optionally, the number of the acid supply tanks, which is greater than or equal to two, is used to supply different types of acid.

[0021] Optionally, the capacities of two or more of the acid supply tanks are the same or different.

[0022] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0023] The trough-type wet etching device of the present invention comprises: a process tank, at least one acid liquid supply tank, a connecting pipe and a supporting component, wherein the position of the process tank is lower than that of the acid liquid supply tank, the acid liquid supply tank is connected to the process tank through a connecting pipe, the connecting pipe at least comprises a connected transverse pipe and a longitudinal pipe, the inlet end of the transverse pipe is connected to the acid liquid supply tank, the outlet end of the longitudinal pipe is connected to the process tank, the acid liquid supply tank is used to store acid liquid and supply the stored acid liquid to the process tank through the connecting pipe, the process tank is used to dilute the acid liquid supplied by the acid liquid supply tank or mix multiple acid liquids supplied to perform an etching process; the supporting component is in contact with the transverse pipe to keep the transverse pipe horizontal. In the present invention, a supporting component is provided, and the supporting component is in contact with the transverse pipe. The transverse pipe is kept horizontal by the supporting component. Since the transverse pipe is kept horizontal, each time the acid change is completed and the acid supply tank stops supplying acid to the process tank, the transverse pipe will not affect and hinder the remaining acid in the connecting pipe from flowing into the process tank under the action of gravity, so that the amount of residual acid in the transverse pipe remains the same or has a small difference after each acid change, that is, the stopping position of the residual acid in the transverse pipe is fixed or changes slightly, thereby ensuring that the amount of acid added to the process tank is certain each time the acid is changed, so that the concentration of the acid in the process tank reaches the set concentration value, the concentration of the acid can be kept stable, which is conducive to the etching process, greatly reducing or avoiding the alarm of high or low acid concentration in the slot type wet etching device, ensuring the working stability of the slot type wet etching device, improving the output of the slot type wet etching device, and saving manpower and material resources.

[0024] Furthermore, the distance between the position where the support frame is fixed to the transverse pipe and the acid supply tank is 1 / 4-1 / 3 of the total length of the transverse pipe, which can more conveniently and better keep the transverse pipe in the connecting pipe level and prevent the connecting pipe from deforming, so that the transverse pipe will not affect and hinder the remaining acid in the transverse pipe from flowing into the process tank under the action of gravity, so that the amount of residual acid in the transverse pipe can be better maintained the same or with a smaller difference after each acid change.

[0025] Furthermore, it also includes a pure water supply end for supplying pure water to the process tank to dilute the acid solution in the process tank, so that the process tank of the tank-type wet etching device of the present invention can provide a dilute acid solution with a stable concentration.

[0026] Furthermore, the number of the acid solution supply tanks, which is greater than or equal to two, is used to supply different types of acid solutions, so that a mixed acid solution with a stable concentration can be provided in the process tank of the tank-type wet etching device of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of a trench-type wet etching device according to an embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of the process of a trench wet etching device according to another embodiment of the present invention;

[0029] Figure 3 The figure is a schematic diagram of the process of a trench wet etching device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0030] As mentioned in the background art, the aforementioned method of forming diluted hydrofluoric acid in an acid tank or a process tank easily makes the concentration of the formed hydrofluoric acid too low or too high, which is not conducive to the etching process, and it is time-consuming and laborious to eliminate the concentration alarm.

[0031] Research has found that when diluted hydrofluoric acid is formed in the acid tank or process tank, the tank-type wet etching equipment will detect the concentration of hydrofluoric acid in the acid tank or process tank. When the concentration of hydrofluoric acid in the acid tank or process tank is too high (the measured concentration value is greater than the set concentration value) or too low (the measured concentration value is less than the set concentration value), a corresponding alarm will be given to stop the etching process. When such an alarm occurs, the equipment personnel usually need to manually change the acid so that the concentration of hydrofluoric acid in the acid tank or process tank reaches the set concentration to eliminate the alarm. Specifically, taking the low concentration alarm of hydrofluoric acid in the acid tank or process tank as an example, the equipment personnel need to drain the hydrofluoric acid in the acid tank or process tank first, and then manually change the acid for the first time, and add new acid to the acid tank or process tank (add pure water to the process tank while adding new acid to the process tank, and the amount of the new acid and the amount of pure water added each time the acid is changed are fixed, specifically according to the acid change program setting in the tank wet etching device), after the first acid change, the equipment will have an alarm of high concentration of hydrofluoric acid in the acid tank or process tank, and then the hydrofluoric acid in the acid tank or process tank needs to be drained again, and then the second manual acid change operation is performed, and new acid and a corresponding amount of pure water are added to the acid tank or process tank again, at this time, the concentration of hydrofluoric acid in the acid tank or process tank is equal to or equivalent to the set concentration value, and the alarm of high concentration of hydrofluoric acid in the acid tank or process tank is eliminated, and a normal etching process can be performed. This method of eliminating concentration alarms requires manual acid changes twice, which is time-consuming and labor-intensive, and seriously affects the output of the machine.

[0032] Further research found that the real reason why it takes two acid changes to eliminate the alarm is: please refer to Figure 1 , Figure 11 is a schematic diagram of the structure of a slot etching device in an embodiment, wherein the slot etching device comprises a process slot 100, an acid liquid supply tank 102, and a connecting pipe 103, wherein the position of the process slot 100 is lower than the position of the acid liquid supply tank 102, the acid liquid supply tank 102 is connected to the process slot 100 through the connecting pipe 103, the connecting pipe 103 at least comprises a connected transverse pipe 1031 and a longitudinal pipe 1032, the inlet end of the transverse pipe 1031 is connected to the acid liquid supply tank 102, the outlet end of the longitudinal pipe 1032 is connected to the process slot 100, and the acid liquid supply tank 102 is used to store acid and The stored acid solution is supplied to the process tank 100 through the connecting pipe 103. The process tank 100 is used to dilute the acid solution supplied by the acid solution supply tank 102 or mix multiple acid solutions supplied to perform an etching process. It also includes a pure water supply pipe 106 for supplying pure water to the process tank 100. A control valve 104 is also provided between the transverse pipe 1031 and the acid solution supply tank 102 to control the on-off supply of the acid solution. When the control valve 104 is opened, the acid solution supply tank 102 supplies the acid solution to the process tank 100 through the connecting pipe 103. When the control valve is closed, the acid solution supply tank 102 stops supplying the acid solution to the process tank 100. In actual use, due to the influence of factors such as pipeline installation, the outlet end of the transverse pipe 1031 (the outlet end is the end connected to the longitudinal pipe 1032) will tilt upward. When the control valve 104 is closed, part of the acid in the connecting pipe 103 flows into the process tank 100 by gravity, and part of the acid will still remain in the transverse pipe 1031. However, since one end of the transverse pipe 1031 is tilted upward, the upward tilted transverse pipe 1031 will affect and hinder the acid in the transverse pipe 1031 from flowing into the process tank 100. After each acid change, the amount of acid liquid remaining in the transverse pipe 1031 will be different, that is, the position 105 where the residual acid liquid stays in the transverse pipe 1031 will be different. Therefore, when the equipment personnel manually change the acid, the amount of acid added to the process tank 100 is the sum of the amount of new acid and the amount of acid remaining in the transverse pipe 1031. The amount of new acid is fixed, while the amount of acid remaining in the transverse pipe 1031 is not fixed, so that the amount of acid added to the process tank 100 during each acid change is not fixed. Therefore, at least two manual acid changes are required to make the concentration of the acid liquid 110 in the process tank 100 reach the set concentration value.Specifically, when an alarm of low acid concentration occurs, the amount of acid remaining in the upwardly inclined horizontal pipe 1031 will be greater than the normal amount. When the first manual acid change is performed, the amount of acid added to the process tank 100 is the amount of new acid added and the amount of acid remaining in the horizontal pipe. Therefore, after the first acid change, the concentration of the acid in the process tank 100 will be high. At this time, the acid in the process tank 100 needs to be drained again and the second manual acid change is performed. When the second manual acid change is performed, the excess acid remaining in the horizontal pipe has been discharged during the first manual acid change. After the first manual acid change, there is very little acid remaining in the horizontal pipe. Therefore, after the second acid change, the concentration of the acid in the process tank 100 reaches the set concentration value.

[0033] To this end, the present invention provides a trough-type wet etching device comprising: a process tank, at least one acid liquid supply tank, a connecting pipe and a supporting component, wherein the position of the process tank is lower than the position of the acid liquid supply tank, the acid liquid supply tank is connected to the process tank through a connecting pipe, the connecting pipe at least comprises a connected transverse pipe and a longitudinal pipe, the inlet end of the transverse pipe is connected to the acid liquid supply tank, the outlet end of the longitudinal pipe is connected to the process tank, the acid liquid supply tank is used to store acid liquid and supply the stored acid liquid to the process tank through the connecting pipe, the process tank is used to dilute the acid liquid supplied by the acid liquid supply tank or mix multiple supplied acid liquids to perform an etching process; the supporting component is in contact with the transverse pipe to keep the transverse pipe horizontal. In the present invention, a supporting component is provided, and the supporting component is in contact with the transverse pipe. The transverse pipe is kept horizontal by the supporting component. Since the transverse pipe is kept horizontal, each time the acid change is completed and the acid supply tank stops supplying acid to the process tank, the transverse pipe will not affect and hinder the remaining acid in the connecting pipe from flowing into the process tank under the action of gravity, so that the amount of residual acid in the transverse pipe remains the same or has a small difference after each acid change, that is, the stopping position of the residual acid in the transverse pipe is fixed or changes slightly, thereby ensuring that the amount of acid added to the process tank is certain each time the acid is changed, so that the concentration of the acid in the process tank reaches the set concentration value, the concentration of the acid can be kept stable, which is conducive to the etching process, greatly reducing or avoiding the alarm of high or low acid concentration in the slot type wet etching device, ensuring the working stability of the slot type wet etching device, improving the output of the slot type wet etching device, and saving manpower and material resources.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. When describing the embodiments of the present invention in detail, for the sake of convenience, the schematic diagrams will not be partially enlarged according to the general proportion, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0035] In one embodiment of the present invention, a trench type wet etching device is provided. Figure 2 , including: a process tank 100, at least one acid supply tank 102, a connecting pipe 103 and a supporting component 108, wherein,

[0036] The position of the process tank 100 is lower than that of the acid liquid supply tank 102. The acid liquid supply tank 102 is connected to the process tank 100 through a connecting pipe 103. The connecting pipe 103 at least includes a connected transverse pipe 1031 and a longitudinal pipe 1032. The inlet end of the transverse pipe 1031 is connected to the acid liquid supply tank 102, and the outlet end of the longitudinal pipe 1032 is connected to the process tank 100. The acid liquid supply tank 102 is used to store acid liquid and supply the stored acid liquid to the process tank 100 through the connecting pipe 103. The process tank 100 is used to dilute the acid liquid supplied by the acid liquid supply tank 102 or mix a plurality of supplied acid liquids to perform an etching process.

[0037] The supporting member 108 is in contact with the transverse pipe 1031 to keep the transverse pipe 1031 horizontal.

[0038] Specifically, the process tank 100 is a tank used for etching process. The process tank 100 contains acid solution 110 for etching. When etching is required, the wafer is transported from the outside of the process tank 100 to the process tank 100 through a transport device, and the wafer is immersed in the acid solution in the process tank 100. After a specific time, the wafer is taken out of the process tank 100 for subsequent processes (such as cleaning process, etc.).

[0039] The acid solution 110 in the process tank 100 can be a single acid solution or a mixed acid solution. The single acid solution can be diluted hydrofluoric acid, phosphoric acid solution, nitric acid solution or other single acid solution. The mixed acid solution can be a mixed acid solution of hydrofluoric acid and nitric acid or other mixed acid solution.

[0040] The top of the process tank 100 may have a top substrate 101 , and the top substrate 101 is used to close the opening of the process tank 100 and to fix one end of some connecting pipes.

[0041] Each slot etching device has its own corresponding acid supply tank 102, and the acid supply tank 102 is used to store acid and supply the stored acid to the process tank 100 of the specific slot etching device through a connecting pipe 103. The acid supply tank 102 can be connected to the factory liquid supply end through a specific connecting pipe. The factory liquid supply end can continuously supply acid to the acid supply tank 102 corresponding to each slot etching device through the connecting pipe. A control valve is provided on the connecting pipe between each acid supply tank 102 and the factory liquid supply end to control the on and off of the acid supply.

[0042] The position of the acid liquid supply tank 102 is higher than the process tank 100, and the acid liquid supply tank 102 can be arranged in a liquid supply cabinet. In this embodiment, when the acid liquid supply tank 102 supplies acid liquid to the process tank 100, the acid liquid flows into the process tank 100 through the connecting pipe 103 by the action of gravity. In other embodiments, the acid liquid in the acid liquid supply tank 102 can be applied with appropriate pressure.

[0043] The acid liquid supply tank 102 has a specific capacity, which may be 0.5 L, 1 L, 1.5 L, 2 L or other suitable capacities.

[0044] In this embodiment, the number of the acid supply tank 102 is one, and the acid supply tank 102 is used to supply a certain type of acid, such as hydrofluoric acid or other types of acid. The tank-type wet etching device also includes a pure water supply end 106, which is used to supply pure water to the process tank 100 to dilute the acid in the process tank 100. A control valve 107 can also be provided on the pure water supply end 106 to control the on and off of the process of pure water to the process tank 100. In a specific embodiment, before etching, a certain volume of undiluted hydrofluoric acid (such as HF with a molar concentration of 49%) is supplied to the process tank 100 through the acid supply tank 102, and a certain volume of pure water (DIW) is supplied to the process tank 100 through the pure water supply end 106, and the two are mixed to form diluted hydrofluoric acid (for example, the volume ratio of water to HF in the diluted hydrofluoric acid is 200:1).

[0045] In other embodiments, the number of the acid liquid supply tanks 102 may be greater than or equal to two, and the acid liquid supply tanks 102 greater than or equal to two are communicated with the process tank 100 through different connecting pipes. In one embodiment, when the number of the acid liquid supply tanks 102 may be greater than or equal to two, the capacity of the acid liquid supply tanks 102 may be different, and the acid liquid supply tanks 102 of different capacities may store and supply the same or different types of acid liquids to the process tank 100. In another embodiment, when the number of the acid liquid supply tanks 102 may be greater than or equal to two, the capacity of the acid liquid supply tanks 102 may be the same, and different acid liquid supply tanks 102 may store and supply different types of acid liquids to the process tank 100, so as to form a mixed acid solution for etching in the process tank 100.

[0046] A control valve 104 is provided between the acid supply tank 102 and the transverse pipe 103, and the control valve 104 is used to control the on-off of the acid supply tank 102 supplying acid to the process tank 100. At the beginning of each acid change, the control valve is opened, and the acid supply tank 102 supplies acid to the process tank 100. At the end of the acid change, the control valve 104 is closed, and the acid supply tank 102 stops supplying acid to the process tank 100.

[0047] The connecting pipeline 103 at least includes a connected transverse pipeline 1031 and a longitudinal pipeline 1032, the transverse pipeline 1031 refers to the pipeline being arranged transversely, and the longitudinal pipeline 1032 refers to the pipeline being arranged longitudinally, the transverse pipeline 1031 includes an inlet end and an outlet end, and the longitudinal pipeline 1032 includes an inlet end and an outlet end, the inlet end of the transverse pipeline 1031 is connected to the acid supply tank 102 and fixed on the liquid supply cabinet or the acid supply tank 102, the outlet end of the transverse pipeline 1031 is connected to the inlet end of the longitudinal pipeline 1032, and the outlet end of the longitudinal pipeline 1032 is fixed on the top base 101 and passes through the top base 101 to penetrate into the process tank 100, and when there is no supporting component to support it, the transverse pipeline 1031 is inclined upward from the inlet end to the outlet end (such as Figure 1In the embodiment of the present invention, a support component 108 is provided, and the support component 108 contacts the transverse pipe 1031. The support component 108 reduces the upward inclination angle of the transverse pipe 1031 (specifically, the support component 108 raises the part of the transverse pipe 1031 close to the inlet end or pulls down the part of the transverse pipe 1031 close to the outlet end), so that the transverse pipe 1031 remains horizontal. Since the transverse pipe 1031 remains horizontal, each time the acid exchange is completed and the acid supply tank 102 stops supplying acid to the process tank 100 (or each time the control valve is closed after the acid exchange is completed), the transverse pipe 1031 will not affect and hinder the connection. The remaining acid in the connecting pipe 103 flows into the process tank 100 under the action of gravity, so that the amount of residual acid in the transverse pipe 1031 remains the same or has a small difference after each acid change, that is, the stopping position 105 of the residual acid in the transverse pipe is fixed or changes slightly, thereby ensuring that the amount of acid added to the process tank 100 is certain each time the acid is changed, so that the concentration of the acid in the process tank reaches the set concentration value, the concentration of the acid can be kept stable, which is conducive to the etching process, greatly reducing or avoiding the alarm of high or low acid concentration in the tank wet etching device, ensuring the working stability of the tank wet etching device, improving the output of the tank wet etching device, and saving manpower and material resources.

[0048] In this embodiment, reference Figure 2 The support member 108 is a support member, one end of the support member 105 is fixedly connected to the transverse pipe 1031, and the other end of the support member 105 is fixedly connected to the top base. In another embodiment, please refer to Figure 3 The supporting component 108 is a suspension component, one end of which is fixedly connected to the transverse pipe 1031, and the other end of which is fixedly connected to the outer wall of the acid supply tank 102 or the outer wall of the liquid supply cabinet.

[0049] The distance between the position where the support component is fixed to the transverse pipe and the acid supply tank is less than 1 / 2 of the total length of the transverse pipe. Specifically, the distance between the position where the support frame is fixed to the transverse pipe and the acid supply tank is 1 / 4-1 / 3 of the total length of the transverse pipe. This can more conveniently and better keep the transverse pipe 1031 in the connecting pipe horizontal and prevent the connecting pipe from deforming, so that the transverse pipe 1031 will not affect and hinder the remaining acid in the transverse pipe 1031 from flowing into the process tank 100 under the action of gravity, so that the amount of residual acid in the transverse pipe 1031 can be better maintained the same or with a smaller difference after each acid change.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A trench wet etching device, characterized in that: include: process tank, at least one acid supply tank, connecting pipes and support components, wherein: The position of the process tank is lower than that of the acid liquid supply tank, the acid liquid supply tank is connected to the process tank through a connecting pipe, the connecting pipe at least includes a connected transverse pipe and a longitudinal pipe, the inlet end of the transverse pipe is connected to the acid liquid supply tank, and the outlet end of the longitudinal pipe is connected to the process tank, the acid liquid supply tank is used to store acid liquid and supply the stored acid liquid to the process tank through the connecting pipe, and the process tank is used to dilute the acid liquid supplied by the acid liquid supply tank or mix multiple acid liquids supplied to perform an etching process; The supporting component is in contact with the transverse pipe and is used to keep the transverse pipe horizontal, so that each time the acid change is completed and the acid supply tank stops supplying acid to the process tank, the transverse pipe will not affect and hinder the remaining acid in the connecting pipe from flowing into the process tank under the action of gravity, so that the amount of residual acid in the transverse pipe remains the same or has a small difference after each acid change.

2. The trench wet etching device according to claim 1, characterized in that: The transverse pipe includes an inlet end and an outlet end, and the longitudinal pipe includes an inlet end and an outlet end. The inlet end of the transverse pipe is connected to the acid supply tank, and the outlet end of the transverse pipe is connected to the inlet end of the longitudinal pipe. The transverse pipe is inclined upward from the inlet end to the outlet end. The supporting component is in contact with the transverse pipe, and the upward inclination angle of the transverse pipe is reduced by the supporting component, so that the transverse pipe remains horizontal.

3. The trench wet etching device according to claim 1, characterized in that: The top of the process tank is provided with a top base, and the longitudinal pipe passes through the top base to process acid liquid into the process tank.

4. The trench wet etching device according to claim 3, characterized in that: The supporting component is a supporting member, one end of which is fixedly connected to the transverse pipe, and the other end of which is fixedly connected to the top base.

5. The trench wet etching device according to claim 3, characterized in that: The supporting component is a hanging component, one end of which is fixedly connected to the transverse pipe, and the other end of which is fixedly connected to the outer wall of the acid liquid supply tank.

6. The trench wet etching device according to claim 4 or 5, characterized in that: The distance between the position where the supporting component is fixed to the transverse pipeline and the acid liquid supply tank is less than 1 / 2 of the total length of the transverse pipeline.

7. The trench wet etching device according to claim 6, characterized in that: The distance between the position where the supporting component is fixed to the transverse pipeline and the acid liquid supply tank is 1 / 4-1 / 3 of the total length of the transverse pipeline.

8. The trench wet etching device according to claim 1, characterized in that: A control valve is provided between the acid supply tank and the transverse pipeline, and the control valve is used to control the on-off supply of acid from the acid supply tank to the process tank. The control valve is opened at the beginning of each acid change, and is closed at the end of the acid change. After the control valve is closed at the end of each acid change, the amount of acid remaining in the transverse pipeline is the same.

9. The trench wet etching device according to claim 1, characterized in that: It also includes a pure water supply end, which is used to supply pure water to the process tank to dilute the acid solution in the process tank.

10. The trench wet etching device according to claim 9, characterized in that: The acid liquid supplied by the acid liquid supply tank is hydrofluoric acid, and the pure water dilutes the hydrofluoric acid supplied to the process tank.

11. The trench wet etching device according to claim 1 or 9, characterized in that: When the number of the acid liquid supply tanks is greater than or equal to two, the greater than or equal to two acid liquid supply tanks are connected to the process tank through different connecting pipes.

12. The trench wet etching device according to claim 11, characterized in that: The number of the acid liquid supply tanks greater than or equal to two is used to supply different types of acid liquids.

13. The trench wet etching device according to claim 11, characterized in that: The capacities of the two or more acid liquid supply tanks are the same or different.

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