Buffer for photoresist supply pipeline

Abstract

The invention belongs to the technical field of semiconductor equipment, and particularly relates to a buffer for a photoresist supply pipeline, which comprises a cylinder main body, an upper cover and a lower cover, the upper cover is provided with a waste discharge duct for communicating with an external waste discharge pipeline, the lower cover is provided with a liquid inlet and a liquid outlet, the liquid inlet is communicated with an external liquid inlet pipeline, and the liquid outlet is communicated with a liquid outlet pipeline. And the liquid outlet is communicated with an external liquid outlet pipeline. The lower cover is provided with an anti-backflow boss part, an inverted-cone-shaped liquid passing space, a liquid outflow hole and the like, and a blocking ball is arranged in the inverted-cone-shaped liquid passing space. When the photoresist is filled excessively, the photoresist can be effectively prevented from flowing back to the liquid inlet pipeline, one-way flow control over the photoresist is automatically achieved, and liquid level detection is prevented from being interfered; and high-pressure gas or redundant photoresist in the inner cavity of the barrel main body can be reliably discharged, and meanwhile, the air pressure in the inner cavity of the barrel main body is kept stable, so that the stable operation of the photoresist pump is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor equipment, in particular to a buffer for a photoresist supply pipeline. Background Art

[0002] At present, a buffer is usually required to be set on the photoresist supply pipeline of semiconductor equipment, which can cooperate with the photoresist bottle and the glue pump in the glue supply system of the equipment to supply the photoresist to each process position and play a buffering role when supplying the photoresist. The buffer 001 in the current prior art generally includes a buffer cylinder and a liquid level sensor installed on the buffer cylinder.

[0003] The buffer cylinder of the buffer 001 of the prior art, such as Figure 4 As shown, a waste outlet connected to a waste discharge pipeline is generally provided at the lower end, a liquid inlet connected to a liquid inlet pipeline is provided in the middle of the upper end, and a liquid outlet connected to a liquid outlet pipeline is provided on one side of the upper end. However, this structure is more likely to cause excessive filling of photoresist when supplying photoresist to the buffer cylinder (at this time, the liquid inlet pipeline is opened, the liquid outlet pipeline remains closed, and the waste discharge pipeline is opened to discharge the gas in the buffer cylinder), causing the photoresist to flow back to the liquid inlet pipeline, and even affecting subsequent normal use. Summary of the invention

[0004] In view of the above problems, the object of the present invention is to provide a buffer for a photoresist supply pipeline.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] A buffer for a photoresist supply pipeline comprises a barrel body, an upper cover and a lower cover, wherein both upper and lower ends of the barrel body are open, the upper cover is used to close the upper end opening of the barrel body, and the lower cover is used to close the lower end opening of the barrel body;

[0007] The upper cover is provided with a waste discharge channel for connecting to an external waste discharge pipeline;

[0008] The lower cover is respectively provided with a liquid inlet and a liquid outlet, the liquid inlet is connected to an external liquid inlet pipeline, the liquid outlet is connected to an external liquid outlet pipeline, an anti-backflow boss portion is convexly provided on the inner side surface of the lower cover located in the cylinder body, an inverted cone-shaped liquid passing space is provided inside the anti-backflow boss portion, the inner aperture size of the upper end opening of the inverted cone-shaped liquid passing space is larger than the inner aperture size of the lower end opening of the inverted cone-shaped liquid passing space, the lower end opening of the inverted cone-shaped liquid passing space is adjacent to the liquid inlet, and the inverted cone-shaped liquid passing space is adjacent to the liquid inlet. The inverted cone-shaped liquid passage space is directly connected to the inverted cone-shaped liquid passage space, and a plurality of liquid outflow holes are opened on the top surface of the anti-backflow boss portion. Each of the liquid outflow holes is located above the upper end opening of the inverted cone-shaped liquid passage space and is connected to the inverted cone-shaped liquid passage space. A baffle ball is provided in the inverted cone-shaped liquid passage space. The diameter of the baffle ball is larger than the inner aperture size of the lower end of the inverted cone-shaped liquid passage space and smaller than the aperture size of each of the liquid outflow holes. The height position of the liquid outlet is lower than the height position of each of the liquid outflow holes.

[0009] A flow guiding slope which gradually slopes downward from a direction away from the liquid outlet to a direction close to the liquid outlet is formed on the inner side surface of the lower cover located in the cylinder body and at the outer peripheral position of the liquid outlet.

[0010] The liquid inlet is connected to an external liquid inlet pipeline through a thread, and the liquid outlet is connected to an external liquid outlet pipeline through a thread.

[0011] The upper cover is provided with a spring piston mounting hole, the spring piston mounting hole having upper and lower openings, the upper opening of the spring piston mounting hole being located on the top surface of the upper cover located on the outside of the cylinder body, and the lower opening of the spring piston mounting hole being located on the inner side surface of the upper cover located in the cylinder body;

[0012] The upper cover is also provided with an atmosphere communication hole A and an atmosphere communication hole B, wherein the atmosphere communication hole A has two openings, one of which is located on the inner side of the upper cover located in the cylinder body, and the other opening of the atmosphere communication hole A is connected to the spring piston mounting hole, and the atmosphere communication hole B has two openings, one of which is directly connected to the atmosphere, and the other opening of the atmosphere communication hole B is connected to the spring piston mounting hole;

[0013] One of the openings of the waste discharge channel is used to communicate with an external waste discharge pipeline, and the other opening of the waste discharge channel is connected to the spring piston installation channel;

[0014] The spring piston mounting channel is installed with a spring piston assembly; in the initial state, the spring piston assembly enables the inner cavity of the cylinder body, the atmosphere connecting channel A and the atmosphere connecting channel B to be connected, and blocks the other opening of the waste discharge channel so that the waste discharge channel is not connected to the inner cavity of the cylinder body; when the pressure in the inner cavity of the cylinder body increases abnormally, the spring piston assembly enables the other opening of the waste discharge channel to be connected to the inner cavity of the cylinder body, and the atmosphere connecting channel A and the atmosphere connecting channel B are not connected.

[0015] The spring piston assembly comprises a mounting cover, a spring and a piston member, wherein the mounting cover is mounted at the upper end opening of the spring piston mounting hole, the piston member is filled and arranged in the spring piston mounting hole, and the bottom part of the mounting cover located in the spring piston mounting hole is connected to the top end of the piston member through the spring;

[0016] An annular connecting groove is provided on the outer peripheral surface of the piston member; in an initial state, the annular connecting groove is directly connected with the atmospheric connecting hole A and the atmospheric connecting hole B respectively; when the pressure in the inner cavity of the cylinder body increases abnormally, the annular connecting groove is staggered with the atmospheric connecting hole A and the atmospheric connecting hole B, and the other opening of the atmospheric connecting hole A and the other opening of the atmospheric connecting hole B are respectively blocked by the outer peripheral surface of the piston member.

[0017] The mounting cover is mounted on the upper opening of the spring piston mounting hole through threads.

[0018] One of the openings of the waste discharge channel is located on the top surface of the upper cover located outside the cylinder body, and is threadedly connected to a waste discharge pipe joint, and the waste discharge pipe joint is connected to an external waste discharge pipeline.

[0019] A liquid level detection tube communicating with the inner cavity of the cylinder body is arranged on the outer side of the cylinder body, and a liquid level detection sensor is installed on the liquid level detection tube.

[0020] The axial center line of the liquid level detection tube is parallel to the axial center line of the cylinder body.

[0021] The cylinder body and the cylinder body are integrally formed.

[0022] The advantages and positive effects of the present invention are:

[0023] 1. The present invention can effectively prevent the photoresist from flowing back into the liquid inlet pipeline when the photoresist is overfilled, automatically realize the one-way flow control of the photoresist, and avoid interference with the liquid level detection.

[0024] 2. The present invention can also reliably discharge the high-pressure gas or excess photoresist in the inner cavity of the cylinder body when the photoresist is overfilled, while maintaining the gas pressure in the inner cavity of the cylinder body stable, thereby ensuring the stable operation of the glue pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the external structure of the present invention;

[0026] Figure 2 It is a schematic diagram of the cross-sectional structure of the present invention in the initial state;

[0027] Figure 3 It is a schematic diagram of the cross-sectional structure of the present invention when the pressure in the inner cavity of the cylinder body increases abnormally;

[0028] Figure 4 The figure is a schematic diagram of the structure of the buffer in the prior art.

[0029] In the figure: 1 is the cylinder body, 101 is the liquid level detection tube;

[0030] 2 is the upper cover, 201 is the waste discharge channel, 202 is the spring piston installation channel, 203 is the atmosphere communication channel A, and 204 is the atmosphere communication channel B;

[0031] 3 is a lower cover, 301 is a liquid inlet, 302 is a liquid outlet, 303 is a backflow prevention boss, 304 is an inverted cone-shaped liquid passing space, and 305 is a liquid outflow hole;

[0032] 4 is a stopper ball, 5 is a stopper cover, 6 is a spring, 7 is a piston, 701 is an annular connecting groove, 8 is a waste pipe joint, and 9 is a liquid level detection sensor;

[0033] 001 is a buffer in the prior art, 002 is a liquid inlet pipeline, 003 is a liquid outlet pipeline, and 004 is a waste discharge pipeline. DETAILED DESCRIPTION

[0034] The following is combined with Figure 1-3 The present invention is further described in detail.

[0035] A buffer for a photoresist supply line, such as Figure 1-3 As shown, this embodiment includes a cylinder body 1, an upper cover 2, and a lower cover 3. The upper and lower ends of the cylinder body 1 are both open. The upper cover 2 is used to close the upper end opening of the cylinder body 1, and the lower cover 3 is used to close the lower end opening of the cylinder body 1. In this embodiment, the connection between the upper cover 2 and the lower cover 3 and the cylinder body 1 adopts the existing technology, such as threaded connection.

[0036] The upper cover 2 is provided with a waste discharge channel 201 for connecting to an external waste discharge pipeline 004 , so as to discharge excess photoresist when too much photoresist is filled into the inner cavity of the cylinder body 1 .

[0037] The lower cover 3 is provided with a liquid inlet 301 and a liquid outlet 302, respectively. The liquid inlet 301 is connected to the external liquid inlet pipeline 002, and the liquid outlet 302 is connected to the external liquid outlet pipeline 003. The inner side surface of the lower cover 3 located in the cylinder body 1 is provided with an anti-backflow boss portion 303, and the interior of the anti-backflow boss portion 303 is provided with an inverted cone-shaped liquid passing space 304. The inner aperture size of the upper end opening of the inverted cone-shaped liquid passing space 304 is larger than the inner aperture size of the lower end opening of the inverted cone-shaped liquid passing space 304. The lower end opening of the inverted cone-shaped liquid passing space 304 is connected to the inlet The liquid port 301 is directly connected, and a plurality of liquid outflow holes 305 are opened on the top surface of the anti-backflow boss portion 303. Each liquid outflow hole 305 is located above the upper end opening of the inverted cone liquid passage space 304 and is connected to the inverted cone liquid passage space 304. A baffle ball 4 is provided in the inverted cone liquid passage space 304. The diameter of the baffle ball 4 is larger than the inner aperture size of the lower end opening of the inverted cone liquid passage space 304 and smaller than the aperture size of each liquid outflow hole 305. The height position of the liquid outlet 302 is lower than the height position of each liquid outflow hole 305.

[0038] During normal use, a glue pump is used to extract photoresist through the liquid outlet pipeline 003. The photoresist in the photoresist glue bottle first enters the inner cavity of the barrel body 1 from the liquid inlet pipeline 002, and then flows out from the liquid outlet pipeline 003, thereby normally playing a buffering role when supplying the photoresist. Normally, the photoresist first enters the lower end opening of the inverted cone liquid passing space 304 through the lower end opening of the inverted cone liquid passing space 304 from the liquid inlet pipeline 002 and lifts the blocking ball 4. After that, the photoresist flows upward through the upper end opening of the inverted cone liquid passing space 304 and each liquid outflow hole 305 to the inner cavity of the barrel body 1. When the photoresist is overfilled, the gravity of the photoresist itself and the downward pressure generated by the obstruction of the upward flow of the photoresist will press the blocking ball 4 and block the lower end opening of the inverted cone liquid passing space 304, which can effectively prevent the photoresist from flowing back into the liquid inlet pipeline 002. The setting of the anti-backflow boss portion 303 can effectively prevent the photoresist located at the lower side of the top surface of the anti-backflow boss portion 303 from flowing back into the inverted tapered liquid passing space 304. Each liquid outflow hole 305 allows the photoresist to fully flow out of the inverted tapered liquid passing space 304 during normal use, and because the diameter of the blocking ball 4 is smaller than the aperture size of each liquid outflow hole 305, the blocking ball 4 will not be pushed out of the inverted tapered liquid passing space 304 by the photoresist during normal use.

[0039] Specifically, in this embodiment, a guide slope is formed on the inner side surface of the lower cover 3 located in the cylinder body 1 and at the outer peripheral position of the liquid outlet 302, which gradually slopes downward from the direction away from the liquid outlet 302 to the direction close to the liquid outlet 302, so as to facilitate the photoresist to fully flow out of the liquid outlet 302.

[0040] Specifically, in this embodiment, the liquid inlet 301 is connected to the external liquid inlet pipeline 002 through a thread, and the liquid outlet 302 is connected to the external liquid outlet pipeline 003 through a thread, which is convenient for disassembly and assembly.

[0041] Specifically, in this embodiment, a spring piston mounting hole 202 is opened on the upper cover 2, and the spring piston mounting hole 202 has upper and lower openings. The upper end opening of the spring piston mounting hole 202 is located on the top surface of the upper cover 2 located on the outside of the cylinder body 1, and the lower end opening of the spring piston mounting hole 202 is located on the inner side surface of the upper cover 2 located in the cylinder body 1.

[0042] The upper cover 2 is also provided with an atmospheric communication channel A 203 and an atmospheric communication channel B 204. The atmospheric communication channel A 203 has two openings. One of the openings of the atmospheric communication channel A 203 is located on the inner side surface of the upper cover 2 located in the cylinder body 1, and the other opening of the atmospheric communication channel A 203 is connected to the spring piston mounting channel 202. The atmospheric communication channel B 204 has two openings. One of the openings of the atmospheric communication channel B 204 is directly connected to the atmosphere, and the other opening of the atmospheric communication channel B 204 is connected to the spring piston mounting channel 202.

[0043] One of the openings of the waste discharge channel 201 is used to communicate with the external waste discharge pipeline 004 , and the other opening of the waste discharge channel 201 is connected to the spring piston installation channel 202 .

[0044] The spring piston installation channel 202 is installed with a spring piston assembly, which includes an installation cover 5, a spring 6 and a piston member 7. The installation cover 5 is installed at the upper end opening of the spring piston installation channel 202, and the piston member 7 is filled and arranged in the spring piston installation channel 202. The bottom part of the installation cover 5 located in the spring piston installation channel 202 is connected to the top of the piston member 7 through the spring 6. An annular connecting groove 701 is provided on the outer peripheral surface of the piston member 7. In this embodiment, the installation cover 5 is installed at the upper end opening of the spring piston installation channel 202 by threading, which is convenient for disassembly and assembly and has good air tightness.

[0045] The annular communication groove 701 is directly connected to the atmosphere communication hole A 203 and the atmosphere communication hole B 204 in the initial state, so that the gas in the inner cavity of the cylinder body 1 can be discharged from the atmosphere communication hole B 204 to ensure the reliable input of the photoresist; at this time, the spring 6 is not compressed. In normal use, the atmosphere communication hole A 203 and the atmosphere communication hole B 204 remain connected. When too much photoresist is filled into the inner cavity of the cylinder body 1, and the pressure in the inner cavity of the cylinder body 1 increases abnormally, the piston member 7 is lifted under the pressure of the gas or liquid in the inner cavity of the cylinder body 1, the spring 6 is compressed, the annular connecting groove 701 is staggered with the atmosphere connecting hole A 203 and the atmosphere connecting hole B 204, and the other opening of the atmosphere connecting hole A 203 and the other opening of the atmosphere connecting hole B 204 are blocked by the outer peripheral surface of the piston member 7, so that the other opening of the exhaust hole 201 is connected with the inner cavity of the cylinder body 1, so as to discharge the high-pressure gas or excess photoresist in the inner cavity of the cylinder body 1 through the exhaust pipe 004. At this time, the atmosphere connecting hole A 203 and the atmosphere connecting hole B 204 are not connected. After the high-pressure gas or excess photoresist in the inner cavity of the cylinder body 1 is discharged through the exhaust pipe 004, the piston member 7 falls back under the elastic force of the spring 6, so that the piston member 7 returns to the initial state position. Therefore, the spring piston assembly can automatically switch the gas path according to the changes in the positive and negative pressures inside the cylinder body 1, thereby simplifying the buffer control logic.

[0046] Specifically, one of the openings of the waste discharge channel 201 in this embodiment is located on the top surface of the upper cover 2 located outside the cylinder body 1, and is threadedly connected to a waste discharge pipe joint 8, which is connected to the external waste discharge pipeline 004, so as to facilitate connection with the waste discharge pipeline 004. In this embodiment, the waste discharge pipe joint 8 is a commercially available product.

[0047] Specifically, in this embodiment, the outer side of the cylinder body 1 is provided with a liquid level detection tube 101 connected to the inner cavity of the cylinder body 1, the axial center line of the liquid level detection tube 101 is parallel to the axial center line of the cylinder body 1, and the cylinder body 1 and the cylinder body 1 are integrally formed, which is easy to manufacture. A liquid level detection sensor 9 is installed on the liquid level detection tube 101, which is easy to install. In this embodiment, there are two liquid level detection sensors 9, both of which are commercially available products. The installation structure of the liquid level detection sensor 9 is also the prior art, and the liquid level detection sensor 9 is connected to the external controller. One of them is used to detect whether the liquid level in the liquid level detection tube 101, that is, the cylinder body 1, is too low, and the other is used to detect whether the liquid level in the liquid level detection tube 101, that is, the cylinder body 1, is too high.

[0048] Working principle:

[0049] By setting up the lower cover 3 and the blocking ball 4 with the anti-backflow boss 303, the inverted cone liquid passing space 304, the liquid outflow hole 305, it is possible to effectively prevent the photoresist from flowing back into the liquid inlet pipeline 002 when the photoresist is overfilled, automatically realize the unidirectional flow control of the photoresist, and avoid interference with the liquid level detection.

[0050] In the initial state, the spring piston assembly enables the inner cavity of the cylinder body 1, the atmosphere communication hole A 203 and the atmosphere communication hole B 204 to be connected, and blocks the other opening of the waste discharge hole 201 so that the waste discharge hole 201 is not connected to the inner cavity of the cylinder body 1; in normal use, the atmosphere communication hole A 203 and the atmosphere communication hole B 204 remain connected; when the pressure in the inner cavity of the cylinder body 1 increases abnormally, the spring piston assembly enables the other opening of the waste discharge hole 201 to be connected to the inner cavity of the cylinder body 1, and the atmosphere communication hole A 203 and the atmosphere communication hole B 204 are not connected. When the photoresist is overfilled, the high-pressure gas or excess photoresist in the inner cavity of the cylinder body 1 can be reliably discharged, while the air pressure in the inner cavity of the cylinder body 1 is kept stable, thereby ensuring the stable operation of the glue pump.

Claims

1. A buffer for a photoresist supply pipeline, characterized in that: It comprises a cylinder body (1), an upper cover (2) and a lower cover (3); the cylinder body (1) has openings at both ends, the upper cover (2) is used to close the upper opening of the cylinder body (1), and the lower cover (3) is used to close the lower opening of the cylinder body (1); The upper cover (2) is provided with a waste discharge channel (201) for connecting to an external waste discharge pipeline; The lower cover (3) is provided with a liquid inlet (301) and a liquid outlet (302), respectively; the liquid inlet (301) is communicated with an external liquid inlet pipeline, and the liquid outlet (302) is communicated with an external liquid outlet pipeline; an anti-backflow boss portion (303) is convexly provided on the inner side surface of the lower cover (3) located in the cylinder body (1); an inverted cone-shaped liquid passage space (304) is provided inside the anti-backflow boss portion (303); the inner aperture size of the upper end opening of the inverted cone-shaped liquid passage space (304) is larger than the inner aperture size of the lower end opening of the inverted cone-shaped liquid passage space (304); the lower end opening of the inverted cone-shaped liquid passage space (304) is adjacent to the liquid inlet (301) is directly connected, and a plurality of liquid outflow holes (305) are opened on the top surface of the anti-backflow boss portion (303), and each of the liquid outflow holes (305) is located above the upper end opening of the inverted cone liquid passage space (304) and is connected to the inverted cone liquid passage space (304). A baffle ball (4) is provided in the inverted cone liquid passage space (304), and the diameter of the baffle ball (4) is larger than the inner aperture size of the lower end of the inverted cone liquid passage space (304) and smaller than the aperture size of each of the liquid outflow holes (305). The height position of the liquid outlet (302) is lower than the height position of each of the liquid outflow holes (305).

2. A buffer for a photoresist supply pipeline according to claim 1, characterized in that: A flow guiding slope is formed on the inner side surface of the lower cover (3) located in the cylinder body (1) and at the outer peripheral position of the liquid outlet (302), and the slope gradually inclines downward from a direction away from the liquid outlet (302) to a direction close to the liquid outlet (302).

3. The buffer for a photoresist supply pipeline according to claim 1, characterized in that: The liquid inlet (301) is connected to an external liquid inlet pipeline via a thread, and the liquid outlet (302) is connected to an external liquid outlet pipeline via a thread.

4. A buffer for a photoresist supply pipeline according to claim 1, characterized in that: The upper cover (2) is provided with a spring piston mounting hole (202), the spring piston mounting hole (202) having upper and lower openings, the upper opening of the spring piston mounting hole (202) being located on the top surface of the upper cover (2) located on the outside of the cylinder body (1), and the lower opening of the spring piston mounting hole (202) being located on the inner side surface of the upper cover (2) located in the cylinder body (1); The upper cover (2) is also provided with an atmosphere communication hole A (203) and an atmosphere communication hole B (204), wherein the atmosphere communication hole A (203) has two openings, one of the openings of the atmosphere communication hole A (203) is located on the inner side surface of the upper cover (2) located in the cylinder body (1), and the other opening of the atmosphere communication hole A (203) is connected to the spring piston mounting hole (202), and the atmosphere communication hole B (204) has two openings, one of the openings of the atmosphere communication hole B (204) is directly connected to the atmosphere, and the other opening of the atmosphere communication hole B (204) is connected to the spring piston mounting hole (202); One of the openings of the waste discharge channel (201) is used to communicate with an external waste discharge pipeline, and the other opening of the waste discharge channel (201) is connected to the spring piston installation channel (202); The spring piston installation hole (202) is installed with a spring piston assembly; in an initial state, the spring piston assembly enables the inner cavity of the cylinder body (1), the atmosphere communication hole A (203) and the atmosphere communication hole B (204) to be connected, and blocks the other opening of the waste discharge hole (201) so that the waste discharge hole (201) is not connected to the inner cavity of the cylinder body (1); when the pressure in the inner cavity of the cylinder body (1) increases abnormally, the spring piston assembly enables the other opening of the waste discharge hole (201) to be connected to the inner cavity of the cylinder body (1), and the atmosphere communication hole A (203) and the atmosphere communication hole B (204) are not connected.

5. A buffer for a photoresist supply pipeline according to claim 4, characterized in that: The spring piston assembly comprises a mounting cover (5), a spring (6) and a piston member (7); the mounting cover (5) is mounted at the upper end opening of the spring piston mounting hole (202); the piston member (7) is filled and arranged in the spring piston mounting hole (202); the bottom portion of the mounting cover (5) located in the spring piston mounting hole (202) is connected to the top end of the piston member (7) via the spring (6); An annular communication groove (701) is provided on the outer circumferential surface of the piston member (7); in an initial state, the annular communication groove (701) is directly connected to the atmosphere communication hole A (203) and the atmosphere communication hole B (204) respectively; when the pressure in the inner cavity of the cylinder body (1) increases abnormally, the annular communication groove (701) is staggered with the atmosphere communication hole A (203) and the atmosphere communication hole B (204), and the other opening of the atmosphere communication hole A (203) and the other opening of the atmosphere communication hole B (204) are respectively blocked by the outer circumferential surface of the piston member (7).

6. A buffer for a photoresist supply pipeline according to claim 5, characterized in that: The mounting cover (5) is mounted on the upper opening of the spring piston mounting hole (202) via threads.

7. The buffer for photoresist supply pipeline according to claim 1, characterized in that: One of the openings of the waste discharge channel (201) is located on the top surface of the upper cover (2) located outside the cylinder body (1), and is threadedly connected to a waste discharge pipe joint (8), and the waste discharge pipe joint (8) is connected to an external waste discharge pipeline.

8. The buffer for photoresist supply pipeline according to claim 1, characterized in that: A liquid level detection tube (101) is provided on the outer side of the cylinder body (1) and is in communication with the inner cavity of the cylinder body (1). A liquid level detection sensor (9) is installed on the liquid level detection tube (101).

9. A buffer for a photoresist supply pipeline according to claim 8, characterized in that: The axial center line of the liquid level detection tube (101) and the axial center line of the cylinder body (1) are parallel to each other.

10. A buffer for a photoresist supply pipeline according to claim 8, characterized in that: The cylinder body (1) and the cylinder body (1) are integrally formed.

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