Photoresist pump

Abstract

The invention provides a photoresist pump. The photoresist pump comprises a pump body, a power assembly and an on-off valve assembly, the pump body is provided with a gluing cavity, a buffer cavity, a fluid channel and an exhaust channel, the gluing cavity and the buffer cavity are both communicated with the fluid channel, and the gluing cavity and the buffer cavity can exhaust air through the exhaust channel; the on-off valve assembly is arranged on the pump body, and the on-off valve assembly is communicated with the fluid channel and the exhaust channel and used for controlling a switch communicated with the fluid channel and the exhaust channel; and the power assembly is connected with the pump body and is used for backfilling and distributing photoresist. According to the invention, the fluid channel and the gas channel in the pump body are controlled through the on-off valve assembly, so that bubbles in photoresist in the filter, the buffer cavity and the gluing cavity can be discharged, and the gluing precision is improved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor preparation, and in particular to a photoresist pump. Background Art

[0002] The photolithography process is the most important part of the chip manufacturing process. In actual production, the photolithography machine is usually directly connected to the coating and developing equipment. As the core component of the coating and developing machine, the high-precision and high-cleanliness photoresist pump is used to provide photoresist to the wafer surface, and is used in conjunction with the controller and controller to accurately control important parameters such as the coating amount, coating speed, coating accuracy, and backfilling speed. In the coating process, the coating accuracy of the glue pump directly affects the film thickness of the photoresist on the wafer surface. At the same time, when distributing the photoresist, it is necessary to ensure the high cleanliness of the flow channel and the joint to avoid the surface of the wafer after coating from being contaminated by particles and bubbles.

[0003] In the prior art, the connection pipeline between the pump and the external buffer is relatively long, which increases the probability of bubbles being precipitated when the photoresist flows, affecting the coating accuracy. Summary of the invention

[0004] The purpose of the present invention is to provide a photoresist pump which can filter, exhaust and purify the photoresist, thereby improving the accuracy of glue coating.

[0005] To achieve the above-mentioned object, in a first aspect, the present invention provides a photoresist pump, comprising a pump body, a power assembly and an on-off valve assembly;

[0006] The pump body is provided with a glue-making chamber, a buffer chamber, a fluid channel and an exhaust channel. The glue-making chamber and the buffer chamber are both connected to the fluid channel, and the glue-making chamber and the buffer chamber can be exhausted through the exhaust channel;

[0007] The on-off valve assembly is disposed on the pump body, the on-off valve assembly is communicated with the fluid channel and the exhaust channel, and is used to control the switch of the communication between the fluid channel and the exhaust channel;

[0008] The power assembly is connected to the pump body and is used for backfilling and distributing the photoresist.

[0009] Optionally, a filter connected to the pump body is further included, wherein the filter is used to filter impurities in the photoresist and discharge bubbles in the photoresist.

[0010] Optionally, the filter has a filter liquid inlet, a filter liquid outlet and a filter exhaust port;

[0011] The filter liquid inlet is used to introduce the photoresist;

[0012] The filter liquid outlet is connected to the cache cavity through the fluid channel, and is used to introduce the filtered photoresist into the cache cavity;

[0013] The filter exhaust port is communicated with the exhaust channel and is used to exhaust bubbles in the photoresist.

[0014] Optionally, the pump body is also provided with a liquid receiving port, a distribution port and a pump body exhaust port;

[0015] The liquid receiving port is in communication with the fluid channel, and the liquid receiving port is used to introduce the external photoresist into the pump body;

[0016] The distribution port is connected to the photoresist chamber through the fluid channel, and the distribution port is used to discharge the photoresist;

[0017] The pump body exhaust port is communicated with the exhaust passage.

[0018] Optionally, a liquid level sensor is also provided in the pump body;

[0019] The liquid level sensor is disposed close to the buffer cavity and is used for monitoring the liquid level in the buffer cavity.

[0020] Optionally, a pressure sensor is further provided in the pump body, and the pressure sensor is used to monitor the pressure in the glue-making chamber.

[0021] Optionally, the power assembly includes a telescopic mechanism, a folding diaphragm and a plunger core;

[0022] The folded diaphragm is connected to the pump body, and part of the folded diaphragm can extend into the glue-making cavity;

[0023] One end of the plunger core is fixedly connected to the end surface of the folded membrane, and the other end of the plunger core is connected to the telescopic mechanism;

[0024] The telescopic mechanism provides power to the plunger core to enable the folded membrane to expand and contract, so as to discharge the photoresist in the glue-printing cavity.

[0025] Optionally, the power assembly further includes a positioning member;

[0026] The end surface of the folded membrane is provided with a first positioning hole, and the end of the plunger core close to the folded membrane is provided with a second positioning hole corresponding to the first positioning hole;

[0027] The positioning member is connected to the first positioning hole and the second positioning hole.

[0028] Optionally, the power assembly further includes a base;

[0029] The power assembly further includes a heat conducting member and a connecting plate, wherein the connecting plate is arranged on the base, the telescopic mechanism and the heat conducting member are arranged on a side wall of the connecting plate, and the heat conducting member is in contact with the telescopic mechanism.

[0030] Optionally, a pressing plate is also included;

[0031] A first installation groove is formed on the side wall of the pump body corresponding to the buffer cavity, and the liquid level sensor is arranged in the first installation groove;

[0032] The pressing plate is connected to the first mounting groove and is used to fix the liquid level sensor on the pump body.

[0033] Optionally, a clamping ring and a sealing ring are also included;

[0034] The side wall of the pump body is provided with a mounting hole, the mounting hole is connected to the glue-making chamber, and the inner side wall of the mounting hole is provided with an annular second mounting groove;

[0035] The sealing ring is arranged in the second annular mounting groove;

[0036] The pressure sensor is arranged at the mounting hole, and blocks the mounting hole to seal the glue cavity;

[0037] The clamping ring is arranged on the mounting hole to fix the pressure sensor to the mounting hole.

[0038] The beneficial effect of the present invention is that the air bubbles in the photoresist in the filter, the buffer cavity and the glue coating cavity can be discharged by controlling the fluid channel and the gas channel in the pump body through the on-off valve assembly, thereby improving the glue coating accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of the structure of a photoresist pump according to an embodiment of the present invention;

[0040] Figure 2 A perspective view of a photoresist pump according to an embodiment of the present invention;

[0041] Figure 3 An exploded view of a pump body according to an embodiment of the present invention;

[0042] Figure 4 An exploded view of a power assembly of an embodiment provided by the present invention;

[0043] Figure 5 A schematic diagram of the structure of the embodiment provided by the present invention when the plunger core drives the folded diaphragm to retract;

[0044] Figure 6 A schematic diagram of the structure of the embodiment provided by the present invention when the plunger core drives the folded membrane to extend;

[0045] Figure 7 A perspective view of a plunger core and a folded diaphragm according to an embodiment of the present invention;

[0046] Figure 8 A schematic diagram of a valve plate according to an embodiment of the present invention;

[0047] Fig. 9 A schematic diagram of the embodiment of the present invention when the valve plate and the pneumatic diaphragm cooperate to open the channel in the pump body;

[0048] Fig.10 Schematic diagram of the valve plate and pneumatic diaphragm of the embodiment of the present invention cooperating to close the channel in the pump body

[0049] Fig.11 A schematic diagram of the structure of the connection between each valve in the on-off valve assembly of the embodiment provided by the present invention and the filter, the buffer chamber and the glue-making chamber;

[0050] Fig.12 A timing diagram of each valve in the on-off valve assembly of the embodiment provided by the present invention when working;

[0051] Fig.13 This is a flow chart of a method for controlling a photoresist pump according to an embodiment of the present invention.

[0052] Reference numerals:

[0053] Pump body 100, glue chamber 101, fluid channel 102, buffer chamber 103, liquid level sensor 104, pressure sensor 105, clamping plate 106, first mounting groove 107, clamping ring 108, sealing ring 109, mounting hole 110, second mounting groove 111, joint 112, sealing cover clamping plate 113, exhaust channel 114, power assembly 200, telescopic mechanism 201, folded diaphragm 202, plunger core 203, first Positioning hole 204, second positioning hole 205, base 206, heat conductor 207, connecting plate 208, protective cover 209, left clamping block 210, right clamping block 211, fixing block 212, middle connecting piece 213, first through hole 214, valve plate 301, pneumatic diaphragm 302, groove 303, air connection channel 304, micro connector 305, filter 400, nozzle 500, valve island 600, throttling connector 700. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the usual meanings understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Unless otherwise specified, the "connection" described in this article can be a direct connection or an indirect connection, that is, connected through an intermediate.

[0055] In view of the problems existing in the prior art, an embodiment of the present invention provides a photoresist pump, referring to Figures 1 to 3 As shown, the photoresist comprises a pump body 100, a power assembly 200 and an on-off valve assembly (not shown in the figure). The pump body 100 is provided with a glue-making chamber 101, a buffer chamber 103, a fluid channel 102 and an exhaust channel 114. The on-off valve assembly is connected to the pump body 100, and the on-off valve assembly is used to control the switch of the fluid channel 102 and the exhaust channel 114 in the pump body 100, so as to control the flow of photoresist into the glue-making chamber 101 and discharge the bubbles in the photoresist. The power assembly 200 is connected to the pump body 100, and is used for the pump body 100 to backfill and distribute the photoresist.

[0056] refer to Figure 2 and Figure 3 As shown, a sealing cover pressing plate 113 is provided on the top of the pump body 100, and the sealing cover pressing plate 113 is embedded in the top of the pump body 100 to seal the cache chamber 103. It should be noted that a joint 112 is provided on the sealing cover pressing plate 113, and the three joints 112 include a photoresist inlet joint, a photoresist outlet joint and an exhaust joint. One end of the photoresist inlet joint, the photoresist outlet joint and the exhaust joint are respectively connected to the liquid receiving port (not shown in the figure), the distribution port (not shown in the figure) and the pump body exhaust port (not shown in the figure) on the pump body, and the other ends of the photoresist inlet joint, the photoresist outlet joint and the exhaust joint are connected to an external pipeline. The photoresist inlet joint is connected to the corresponding fluid channel 102 through the liquid receiving port for externally inputting the external photoresist into the pump body 100. The photoresist outlet joint is connected to the distribution port, and is used to discharge the photoresist in the glue chamber 101 and distribute it to the wafer surface. The exhaust joint is used to exhaust the bubbles in the glue chamber 101 , the filter 400 and the cache chamber 103 .

[0057] refer to Figure 1 and Figure 2 As shown, the pump body 100 is connected to the filter 400, and the filter is used to filter the impurities in the photoresist and discharge the bubbles in the photoresist. The filter 400 has a filter liquid inlet (not shown in the figure), a filter liquid outlet (not shown in the figure) and a filter exhaust port (not shown in the figure), the filter liquid inlet is used to introduce the photoresist, the filter liquid outlet is connected to the cache cavity 103 through the fluid channel, and is used to introduce the filtered photoresist into the cache cavity 103, the filter exhaust port is connected to the exhaust channel, and is used to discharge the bubbles in the photoresist, and the photoresist can pass through the filter 400 and the cache cavity 103 in sequence until it is introduced into the glue chamber 101.

[0058] refer to Figure 2 and Figure 4 As shown, in some embodiments, the power assembly 200 includes a telescopic mechanism 201, a folding diaphragm 202 and a plunger core 203. The folding diaphragm 202 is connected to the pump body 100, and part of the folding diaphragm 202 can extend into the glue-making chamber 101. One end of the plunger core 203 is fixedly connected to the inner end surface of the folding diaphragm 202, and the folding diaphragm 202 is extended into the glue-making chamber 101 by extending the plunger core 203, and the folding diaphragm 202 is folded inside and outside and retracted by retracting the plunger core 203. The other end of the plunger core 203 is connected to the telescopic mechanism 201 through an intermediate connecting member 213. The telescopic mechanism 201 provides power to the plunger core 203 to make the folding diaphragm 202 telescopic, which is used for the pump body 100 to backfill and distribute the photoresist.

[0059] Optional, reference Figures 5 to 7 As shown, the power assembly 200 also includes a positioning member (not shown in the figure), and in this embodiment, the positioning member is a pin. The inner end surface of the folded diaphragm 202 is provided with a first positioning hole 204, and one end of the plunger core 203 is provided with a second positioning hole 205 corresponding to the first positioning hole 204. The positioning member is connected to the first positioning hole 204 and the second positioning hole 205. Therefore, when the folded diaphragm 202 is extended and retracted, the folded diaphragm 202 will not rotate with the plunger core 203, thereby ensuring the stable output state of the power assembly 200.

[0060] For further reference, Figure 4As shown, the power assembly 200 further includes a heat conductor 207 and a connecting plate 208, wherein the connecting plate 208 is connected to the base 206, and a side wall of the connecting plate 208 is used to connect the telescopic mechanism 201 and the heat conductor 207, and the heat conductor 207 is attached to the telescopic mechanism 201 to absorb the heat generated by the telescopic mechanism 201. In some embodiments, the telescopic mechanism 201 can also be cooled by water cooling or air cooling.

[0061] In this embodiment, the heat conducting member 207 can be provided to dissipate heat from the telescopic mechanism 201, ensuring that the heat generated by the telescopic mechanism 201 will not be transferred to the photoresist, thereby avoiding affecting the properties of the photoresist itself. In addition, the telescopic mechanism 201 can be a stepping motor. A protective cover 209 can be provided to protect the stepping motor.

[0062] Continue to refer Figure 4 As shown, the power assembly 200 also includes a left clamping block 210, a right clamping block 211, a fixed block 212 and an intermediate connecting piece 213. The intermediate connecting piece 213 is located between the telescopic mechanism 201 and the plunger core 203, and the telescopic end of the telescopic mechanism 201 is connected to the plunger core 203 through the intermediate connecting piece 213. The left clamping block 210 and the right clamping block 211 are both connected to the side of the connecting plate 208, and the left clamping block 210 and the right clamping block 211 cooperate to form a telescopic channel, which is adapted to the plunger core 203, and the plunger core 203 can pass through the telescopic channel, thereby ensuring stability during telescopic operation. The other side of the left clamping block 210 and the right clamping block 211 is connected to the fixed block 212, and the fixed block 212 is provided with a first through hole 214 corresponding to the telescopic channel, and the fixed block 212 is connected to the pump body 100. Part of the folded diaphragm 202 is disposed in the first through hole 214, and the diameter of the fixed end of the folded diaphragm 202 is larger than the diameter of the first through hole 214, and the fixed end of the folded diaphragm 202 is disposed close to the telescopic passage. The pump body 100 is provided with a second through hole (not shown) corresponding to the first through hole 214, and the second through hole is connected to the glue cavity 101, so that part of the folded diaphragm 202 can extend into the glue cavity 101.

[0063] It should be noted that the prior art uses a two-stage pump to achieve distribution control of the photoresist, but when the two-stage pump is working, the two motors work at the same time and generate a lot of heat. The heat generated will not only be transferred to the photoresist through heat, affecting the characteristics of the photoresist itself, but also there is a risk of downtime when the motor works at high temperature for a long time, and the reliability is poor. However, the present implementation only requires one telescopic mechanism 201 to complete the task, and the heat generation is greatly reduced during operation. In addition, the use of a heat conductor 207 ensures that the heat generated by the telescopic mechanism 201 will not be transferred to the photoresist, thereby avoiding the problems existing in the prior art.

[0064] Optional, reference Figure 3 As shown, a liquid level sensor 104 is also provided in the pump body 100. The liquid level sensor 104 is provided outside the buffer cavity 103. When the photoresist enters the buffer cavity 103, the liquid level sensor 104 monitors in real time whether the photoresist in the buffer cavity 103 reaches the target liquid level.

[0065] For details, please refer to Figure 3 As shown, the photoresist pump further includes a clamping plate 106. A first mounting groove 107 is provided on the side wall of the pump body 100 corresponding to the buffer cavity 103. The liquid level sensor 104 is disposed in the first mounting groove 107 and connected to the buffer cavity 103. The clamping plate 106 and the first mounting groove 107 are connected by bolts to fix the liquid level sensor 104 to the pump body 100.

[0066] refer to Figure 3 As shown, a pressure sensor 105 is also provided in the pump body 100, and the pressure sensor 105 is used to monitor the pressure value in the glue-making chamber 101. The pressure sensor 105 is connected to a controller, and the pressure sensor 105 feeds back the monitored pressure value to the controller in real time, and then the power assembly 200 is controlled by the controller to enable the glue-making chamber 101 to discharge the photoresist at a uniform speed.

[0067] refer to Figure 3 As shown, the photoresist pump also includes a clamping ring 108 and a sealing ring 109. The side wall of the pump body 100 is provided with a mounting hole 110, and the mounting hole 110 is connected to the glue-making chamber 101. The inner side wall of the mounting hole 110 is provided with an annular second mounting groove 111. The sealing ring 109 is arranged in the annular second mounting groove 111 to ensure the sealing of the glue-making chamber 101. The pressure sensor 105 is arranged in the mounting hole 110, and the mounting hole 110 is blocked to seal the glue-making chamber 101; the clamping ring 108 is arranged in the mounting hole 110 to fix the pressure sensor 105 to the mounting hole 110. Specifically, the clamping ring 108 is threadedly connected to the mounting hole 110.

[0068] Optional, combined Figures 8 to 10 As shown, the on-off valve assembly includes a valve plate 301 and a pneumatic diaphragm 302. The valve plate 301 is arranged on the side of the pump body 100, and a plurality of grooves 303 and a plurality of air receiving channels 304 are arranged on the valve plate 301. One end of the air receiving channel 304 is connected to the groove 303, and the other end of the air receiving channel 304 is connected to a micro connector 305, and the micro connector 305 is connected to an air pipe. The fluid channel 102 and the exhaust channel 114 are arranged on both sides of the pump body 100 corresponding to the groove 303. The pneumatic diaphragm 302 is arranged between the valve plate 301 and the pump body 100. When a vacuum environment is provided from the micro connector 305, the pneumatic diaphragm 302 is located in the groove 303, so that the corresponding fluid channel 102 is opened. When compressed air or nitrogen is provided from the micro joint 305, the pneumatic diaphragm 302 is fitted with the fluid channel 102 and / or the exhaust channel 114 to close the fluid channel 102 and the exhaust channel 114. The pneumatic diaphragm 302 is made of modified material to ensure that the gas does not pass through the pneumatic diaphragm 302 under high pressure, thereby ensuring the cleanliness of the photoresist in the pump body 100.

[0069] It is understandable that when the pneumatic diaphragm 302 is in motion, it will cause a slight change in the volume of the pump body 100. When the pneumatic diaphragm 302 closes the fluid channel 102, the volume of the pump body 100 becomes smaller, causing the pressure in the pump body 100 to increase. If the outlet valve of the glue chamber 101 is opened at this time, under the action of pressure, a corresponding volume of photoresist will be discharged from the distribution port before the telescopic mechanism 201 works, causing the glue amount to be unstable, thereby affecting the glue coating process. On the contrary, when the fluid channel 102 is opened, the pneumatic diaphragm 302 is adsorbed into the groove 303 of the valve plate 301, which will cause the volume of the pump body 100 to increase and the pressure of the fluid channel 102 to decrease. Therefore, the fluctuation of the pressure in the fluid channel 102 caused by the volume change in the pump body 100 will also cause the amount of glue distributed by the photoresist pump to fluctuate each time, resulting in a loss of glue application accuracy.

[0070] In order to balance the pressure fluctuations in the glue chamber 101, the present invention proposes a corresponding pressure compensation action. Since the volume change caused by the action of the pneumatic diaphragm 302 is fixed, the pressure fluctuation in the glue chamber 101 is also certain. When the pressure in the pump body 100 increases or decreases, the telescopic mechanism 201 (stepping motor) drives the folded diaphragm 202 to shrink backward or extend forward to compensate for the pressure fluctuation, thereby ensuring the glue application accuracy. Specifically, when the pump body 100 distributes photoresist, when the pneumatic diaphragm 302 is located in the groove 303, the depth of the folded diaphragm 202 extending into the glue chamber is L, and when the pneumatic diaphragm 302 is in contact with the channel opening of the fluid channel 102, the depth of the folded diaphragm 202 extending into the glue chamber is M, and L>M.

[0071] For further reference, Figures 8 to 11 As shown, the valve plate 301 and the pneumatic module 302 may constitute an inlet valve (V1), a purge valve (V2), a filter exhaust valve (V3), a cache chamber exhaust valve (V4), a glue-making chamber exhaust valve (V5), a glue-making chamber inlet valve (V6) and a glue-making chamber outlet valve (V7). Among them, the filter exhaust valve (V3) is used to control the opening or closing of the filter exhaust port. The cache chamber exhaust valve (V4) is used to control the opening or closing of the cache chamber exhaust port. The glue-making chamber exhaust valve (V5) is used to control the opening or closing of the glue-making chamber exhaust port. The glue-making chamber inlet valve (V6) is used to open or close the fluid channel 102 for connecting the cache chamber 103 with the glue-making chamber 101. The inlet valve (V1) is used to control the opening or closing of the filter liquid inlet. The cache chamber 103 also has a purge port, and the purge valve (V2) is used to control the opening or closing of the purge port. The pump body is provided with a distribution port, and the distribution port is used to distribute the photoresist in the glue printing chamber 101. The glue printing chamber outlet valve (V7) is used to control the opening or closing of the distribution port.

[0072] Specifically, the inlet valve (V1) is connected to the filter 400 through the fluid channel 102. The filter 400 is connected to the cache chamber 103 through the fluid channel 102, and the filter 400 is connected to the filter exhaust valve (V3) through the exhaust channel 114. The purge valve (V2) is connected to the cache chamber 103 through the fluid channel 102. The cache chamber 103 is connected to the cache chamber exhaust valve (V4) and the glue chamber exhaust valve (V5) respectively through the exhaust channel 114, and the cache chamber 103 is connected to the glue chamber inlet valve (V6) through the fluid channel 102. The glue chamber inlet valve (V6) is used to close or open the fluid channel 102 between the glue chamber 101 and the cache chamber 103. The glue chamber 101 is connected to the glue chamber outlet valve (V7) through the fluid channel 102.

[0073] Optional, reference Figures 1 to 11 As shown, a valve island 600 and a throttle joint 700 are also provided on the base 206, and gas is delivered to the valve plate 301 through a hose (not shown) and a micro joint 305. The valve island 600 provides compressed air or nitrogen and vacuum for the photoresist pump, ensures the accurate opening and closing of the valve plate 301, is connected to the micro joint 305 on the valve plate 301 through a hose, and accurately controls the working timing of the electromagnetic valve through a control module, thereby ensuring the accurate opening and closing of each valve in the on-off valve assembly. If the valve is opened too early, there is not enough pressure to form a columnar fluid, and the photoresist will drip from the tip of the nozzle 500. If the valve is opened too late, the flow rate will be affected, there will be too much liquid flowing at the beginning, and too little liquid flowing at the end, which directly affects the uniformity of the photoresist coated on the wafer surface. In addition, the throttle joint 700 can ensure that the action switching of each valve in the on-off valve assembly is smooth during the opening and closing process. The most important thing is that the steady and slow opening and closing action can ensure that the pressure in the pump body 100 does not change suddenly, thereby ensuring the glue coating accuracy.

[0074] Combination Fig.12 As shown, it should be noted that the photoresist pump of the embodiment provided by the present invention mainly includes a preparation stage, a backfilling stage, a purification stage and a distribution stage when working. Before the photoresist pump works, a certain amount of photoresist needs to be filled in the internal buffer cavity 103 to ensure that the filtered photoresist completes the corresponding function under different valve combinations.

[0075] In another embodiment provided by the present invention, a control method for a photoresist pump is disclosed. The control method is used for the photoresist pump in the above embodiment. Fig.13 As shown, the control method includes:

[0076] S131: Introduce the photoresist from the filter and the buffer chamber into the photoresist chamber in sequence through the fluid channel.

[0077] Combination Fig.11 and Fig.12 As shown, in this step, before the photoresist is introduced into the glue-making chamber 101 from the filter 400 and the buffer chamber 103 in sequence through the fluid channel 102, the following steps are included: opening the inlet valve (V1) and the glue-making chamber exhaust valve (V5), closing the other valves, and the folded diaphragm is retracted from the glue-making chamber 101. Opening the glue-making chamber exhaust valve (V5) and the buffer chamber exhaust valve (V4), closing the other valves, and extending the folded diaphragm into the glue-making chamber 101. Repeat the above steps until the photoresist in the buffer chamber 103 reaches the target liquid level. This stage is the preparation stage. When the liquid level sensor 104 arranged outside the buffer chamber 103 detects that the photoresist in the buffer chamber 103 reaches the target liquid level, the preparation stage stops and enters the backfilling stage.

[0078] During the backfilling stage, the inlet valve (V1) and the glue-making chamber inlet valve (V6) are opened, and the other valves are closed. At this time, the telescopic mechanism drives the folding diaphragm to retract and fold inward, and the liquid (photoresist) enters the cache chamber 103 and the glue-making chamber 101 in turn from the external buffer container upstream of the photoresist pump through the filter 400.

[0079] S132: Open the exhaust channel to remove photoresist bubbles in the photoresist chamber.

[0080] This step is in the purification stage, during which the telescopic mechanism drives the folded diaphragm to extend forward a certain distance (i.e., the folded diaphragm extends into the glue chamber). At the same time, the glue chamber exhaust valve (V5), the purge valve (V2), the inlet valve (V1) and the filter exhaust valve (V3) are all opened, or only the glue chamber exhaust valve (V5) and the purge valve (V2) are opened. The purpose is to remove bubbles that may exist in the glue chamber 101 and the filter 400, to ensure that there are no bubbles in the photoresist sprayed on the wafer surface, thereby improving the spraying accuracy.

[0081] S133: Spray the photoresist in the coating chamber onto the surface of the wafer.

[0082] This step is in the distribution stage, at which time only the glue chamber outlet valve (V7) is opened, and the other valves are closed. Driven by the telescopic mechanism, the photoresist flows from the glue chamber 101 to the wafer surface, completing the glue coating process.

[0083] In addition, in order to further ensure the glue coating accuracy, when gluing, the pressure sensor 105 measures and feeds back the pressure value in the glue coating chamber 101 in real time, and transmits the signal of the pressure value to the controller. The controller adjusts the glue coating speed in real time. When the measured value of the pressure sensor 105 is less than the set pressure, the controller controls the motor speed of the stepper motor to increase. The purpose is to increase the glue coating pressure and ensure that a columnar fluid is formed at the outlet. Similarly, when the measured value of the pressure sensor 105 is greater than the set pressure, the controller controls the motor speed of the stepper motor to decrease. The purpose is to reduce the glue coating pressure and prevent the liquid flow rate at the distribution port from being too fast, causing liquid splashing during glue coating.

[0084] The above is only a specific implementation of the embodiment of the present application, but the protection scope of the embodiment of the present application is not limited thereto, and any changes or replacements within the technical scope disclosed in the embodiment of the present application should be included in the protection scope of the embodiment of the present application. Therefore, the protection scope of the embodiment of the present application should be based on the protection scope of the claims.

Claims

1. A photoresist pump, characterized in that: It includes a pump body, a power assembly and an on-off valve assembly; The pump body is provided with a glue-making chamber, a buffer chamber, a fluid channel and an exhaust channel. The glue-making chamber and the buffer chamber are both connected to the fluid channel, and the glue-making chamber and the buffer chamber can be exhausted through the exhaust channel; The on-off valve assembly is disposed on the pump body, the on-off valve assembly is communicated with the fluid channel and the exhaust channel, and is used to control the switch of the communication between the fluid channel and the exhaust channel; The power assembly is connected to the pump body and is used for backfilling and distributing the photoresist.

2. The photoresist pump according to claim 1, characterized in that: It also includes a filter connected to the pump body, and the filter is used to filter impurities in the photoresist and discharge bubbles in the photoresist.

3. The photoresist pump according to claim 2, characterized in that: The filter has a filter liquid inlet, a filter liquid outlet and a filter exhaust port; The filter liquid inlet is used to introduce the photoresist; The filter liquid outlet is connected to the cache cavity through the fluid channel, and is used to introduce the filtered photoresist into the cache cavity; The filter exhaust port is communicated with the exhaust channel and is used to exhaust bubbles in the photoresist.

4. The photoresist pump according to any one of claims 1 to 3, characterized in that: The pump body is also provided with a liquid receiving port, a distribution port and a pump body exhaust port; The liquid receiving port is in communication with the fluid channel, and the liquid receiving port is used to introduce the external photoresist into the pump body; The distribution port is connected to the photoresist chamber through the fluid channel, and the distribution port is used to discharge the photoresist; The pump body exhaust port is communicated with the exhaust passage.

5. The photoresist pump according to claim 1, characterized in that: A liquid level sensor is also provided in the pump body; The liquid level sensor is disposed close to the buffer cavity and is used for monitoring the liquid level in the buffer cavity.

6. The photoresist pump according to claim 1, characterized in that: The pump body is also provided with a pressure sensor, and the pressure sensor is used to monitor the pressure in the glue-making chamber.

7. The photoresist pump according to claim 1, characterized in that: The power assembly includes a telescopic mechanism, a folding diaphragm and a plunger core; The folded diaphragm is connected to the pump body, and part of the folded diaphragm can extend into the glue-making cavity; One end of the plunger core is fixedly connected to the end surface of the folded membrane, and the other end of the plunger core is connected to the telescopic mechanism; The telescopic mechanism provides power to the plunger core to extend and retract the folded membrane for backfilling and dispensing the photoresist.

8. The photoresist pump according to claim 7, characterized in that: The power assembly also includes a positioning member; The end surface of the folded membrane is provided with a first positioning hole, and the end of the plunger core close to the folded membrane is provided with a second positioning hole corresponding to the first positioning hole; The positioning member is connected to the first positioning hole and the second positioning hole.

9. The photoresist pump according to claim 7 or 8, characterized in that: Also includes a base; The power assembly further includes a heat conducting member and a connecting plate, wherein the connecting plate is arranged on the base, the telescopic mechanism and the heat conducting member are arranged on a side wall of the connecting plate, and the heat conducting member is in contact with the telescopic mechanism.

10. The photoresist pump according to claim 5, characterized in that: Also included is a hold-down plate; A first installation groove is formed on the side wall of the pump body corresponding to the buffer cavity, and the liquid level sensor is arranged in the first installation groove; The pressing plate is connected to the first mounting groove and is used to fix the liquid level sensor on the pump body.

11. The photoresist pump according to claim 6, characterized in that: It also includes a clamping ring and a sealing ring; The side wall of the pump body is also provided with a mounting hole, the mounting hole is connected to the glue-making cavity, and the inner side wall of the mounting hole is provided with an annular second mounting groove; The sealing ring is arranged in the second annular mounting groove; The pressure sensor is arranged at the mounting hole, and blocks the mounting hole to seal the glue cavity; The clamping ring is arranged on the mounting hole to fix the pressure sensor to the mounting hole.

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