Wafer cleaning and drying process, wafer drying machine and cleaning and drying structure assembly thereof

Abstract

The invention discloses a wafer cleaning and drying process, a wafer drying machine and a cleaning and drying structure assembly thereof, relates to the field of wafer cleaning equipment, and can solve the problem of poor regulation and control precision of an electromagnetic pump and a plurality of valves with different calibers through manual adjustment in the prior art. The wafer drying machine comprises a main body and a lifting mechanism connected to the main body. The cleaning and drying structure assembly comprises a drying groove body, a liquid inlet pipe, an IPA bubbling box, a first liquid discharging pipe and a controller. A groove cover is connected to a groove opening of the drying groove body; the first liquid discharge pipe is connected with an electromagnetic pump, a first valve and a flowmeter used for measuring the flow speed of liquid in the first liquid discharge pipe, and the electromagnetic pump and the flowmeter are both electrically connected to the controller so that the controller can control the flow of the electromagnetic pump according to signal feedback of the flow speed of the liquid in the first liquid discharge pipe by the flowmeter.

Description

Technical Field

[0001] The field involved in the present application specifically relates to a wafer cleaning and drying process, a wafer dryer and a cleaning and drying structure assembly thereof. Background Art

[0002] In the process of wafer cleaning and drying, Marangoni dryer is a commonly used equipment. It uses the Marangoni effect, which is a flow phenomenon based on the difference in liquid surface tension. When the surface tension is different on the surface of the liquid, it will cause the liquid to flow. Through this effect, the residual water or solvent on the surface of the wafer can be effectively removed, achieving a water mark-free and pollution-free drying effect.

[0003] In a typical wafer cleaning and drying process, the wafer is first immersed in the cleaning solution in the drying tank for preliminary cleaning. Subsequently, IPA (isopropyl alcohol) gas is introduced into the drying tank to form an IPA gas environment above the water surface. With the slow drainage operation, the wafer gradually separates from the water surface. Since the surface tension of IPA is much smaller than that of water, a surface tension gradient will be generated on the surface of the sloped water flow, resulting in the occurrence of Marangoni convection. At this time, the water is "sucked back" to the water surface, thereby effectively removing the water on the wafer surface, achieving a drying effect, ensuring that there is no water mark remaining on the wafer surface, and meeting the requirements of high cleanliness.

[0004] However, in the prior art, in order to control the drainage speed of the drying tank, an electromagnetic pump and multiple valves of different calibers are usually installed on the drainage pipe connected to the drying tank, and the drainage speed is precisely controlled by manually adjusting the opening and closing of these valves. Because the accuracy of manual adjustment is difficult to meet the ideal requirements, it is difficult to accurately control the drainage speed, which in turn affects the stability of the drying effect. In addition, this design also increases the complexity of operation and places higher requirements on the technical level of the operator. Summary of the invention

[0005] To this end, the present application provides a wafer cleaning and drying process, a wafer dryer and a cleaning and drying structure assembly thereof to solve the problem of poor control accuracy of electromagnetic pumps and multiple valves of different calibers in the prior art through manual adjustment.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] A cleaning and drying structure assembly of a wafer dryer, the wafer dryer comprising a main body and a lifting mechanism connected to the main body and used for lifting a wafer box, the cleaning and drying structure assembly comprising a drying tank body connected to the main body, a liquid inlet pipe connected to the drying tank body and used for injecting a cleaning liquid into the drying tank body, an IPA bubbling box connected to the drying tank body and used for injecting isopropyl alcohol vapor into the drying tank body, a first liquid drain pipe connected to the drying tank body and used for discharging the cleaning liquid in the drying tank body, and a controller connected to the main body;

[0008] The drying tank body is connected to its own notch with a tank cover for sealing its own notch;

[0009] The first liquid discharge pipe is connected to an electromagnetic pump, a first valve and a flow meter for measuring the flow rate of liquid in the first liquid discharge pipe. The electromagnetic pump and the flow meter are both electrically connected to the controller so that the controller controls the flow rate of the electromagnetic pump based on the signal feedback from the flow meter on the flow rate of liquid in the first liquid discharge pipe.

[0010] Optionally, the drying tank body comprises a first tank body connected to the main body and a second tank body connected to the top outer wall of the first tank body, the second tank body and the outer wall of the first tank body form an overflow tank, so that the cleaning liquid overflowing from the first tank body flows into the overflow tank, and the bottom of the overflow tank is connected to a second drain pipe;

[0011] The liquid inlet pipe is connected to the side wall of the first trough body, the first liquid discharge pipe is connected to the bottom wall of the first trough body, the IPA bubbling box is connected to the side wall of the second trough body, and the box opening of the IPA bubbling box is higher than the notch opening of the first trough body, and the trough cover is connected to the notch opening of the second trough body.

[0012] Optionally, a first nitrogen pipe for filling nitrogen into the IPA bubbling box is connected to the side wall of the IPA bubbling box, and the nitrogen is bubbled in the IPA bubbling box to evaporate the IPA solution into the drying tank body.

[0013] Optionally, the main body is connected to a liquid storage tank for storing IPA solution, the liquid storage tank is connected to a first pipeline for supplying IPA solution to the IPA bubbling box, the liquid storage tank is also connected to a second pipeline for discharging the IPA solution in the IPA bubbling box back into the liquid storage tank, the main body is connected to an IPA stock solution barrel on the outside, and a third pipeline is connected between the IPA stock solution barrel and the first pipeline to replenish the IPA solution to the liquid storage tank;

[0014] The first pipe and the second pipe cooperate to maintain the liquid level in the IPA bubbling box at a set height.

[0015] Optionally, the second pipeline is connected with a second valve, the first pipeline is sequentially connected with a third valve, a wind bag pump, a fourth valve and a fifth valve from the liquid storage tank to the IPA bubbling box, the third valve is located between the liquid storage tank and the third pipeline, the wind bag pump, the fourth valve and the fifth valve are located between the third pipeline and the IPA bubbling box, and the third pipeline is connected with a sixth valve;

[0016] A fourth pipeline is connected between the first pipeline and the liquid storage tank, the fourth pipeline is connected to a seventh valve, the first pipeline is connected to a filter, a fifth pipeline is connected between the filter and the liquid storage tank, and the fifth pipeline is connected to an eighth valve.

[0017] Optionally, the first drainage pipe includes a first section connected to the first trough body, a second section connected to an end of the first section away from the first trough body, and a third section connected to an end of the second section away from the first section and used to discharge the cleaning liquid in the first trough body to the outside of the main body, the electromagnetic pump, the first valve and the flowmeter are connected to the second section, the first drainage pipe is connected to a sixth pipe, one end of the sixth pipe is connected to the intersection of the first section and the second section, and the other end is connected to the intersection of the second section and the third section, and the sixth pipe is connected to a ninth valve.

[0018] Optionally, the highest point of the second section is higher than the notch of the first slot body.

[0019] Optionally, the inner diameter of the third section gradually increases from one end close to the second section to the tail end of the third section.

[0020] Optionally, the end of the first nitrogen pipe away from the IPA bubbling box is connected to a gas supply pipe for providing nitrogen, a second nitrogen pipe is connected between the gas supply pipe and the tank cover, the tank cover is connected to a plurality of nitrogen nozzles connected to the second nitrogen pipe, the second nitrogen pipe is connected to a tenth valve and a gas online heater, and the first nitrogen pipe is connected to an eleventh valve.

[0021] Optionally, the liquid inlet pipe is connected to a twelfth valve, the liquid inlet pipe is connected to a seventh pipeline, the seventh pipeline is connected to a thirteenth valve in parallel with the twelfth valve, and the diameter of the thirteenth valve is smaller than the diameter of the twelfth valve.

[0022] The present application discloses a wafer dryer, comprising the cleaning and drying structure assembly of the wafer dryer as described above.

[0023] The present application also discloses a wafer cleaning and drying process, comprising the following steps:

[0024] S1, standby state before wafer cleaning: the thirteenth valve is opened, the twelfth valve is closed, the liquid inlet pipe slowly injects cleaning liquid into the first tank body, the cleaning liquid in the first tank body is in a full and slow overflow state, the overflowing cleaning liquid enters the overflow tank, and is discharged through the second liquid discharge pipe and the third section, the lifting height of the lifting mechanism is at point A, the tank cover is in a closed state, the tenth valve on the second nitrogen pipe is opened, and multiple nitrogen nozzles on the tank cover blow nitrogen into the drying tank body;

[0025] S2, wafer cleaning: the tenth valve on the second nitrogen pipe is closed, the multiple nitrogen nozzles on the tank cover stop blowing nitrogen into the drying tank body, the tank cover is opened, the lifting mechanism is lifted to point B, the wafer box is placed on the lifting mechanism, the lifting mechanism is lowered to point C, the multiple wafers in the wafer box are immersed in the cleaning liquid in the first tank body, and are held up by the wafer holder in the drying tank body, and the tank cover is closed; the twelfth valve on the liquid inlet pipe is opened, the liquid inlet pipe quickly injects cleaning liquid into the first tank body, the cleaning liquid in the first tank body is full and about to overflow, and the fifth valve is opened The twelfth and thirteenth valves are closed, the liquid inlet pipe stops injecting cleaning liquid into the first tank body, the eleventh valve is opened, and the first nitrogen pipe fills nitrogen into the IPA bubbling box, so that the IPA solution in the IPA bubbling box forms nitrogen bubbles, and the IPA is evaporated into the drying tank body;

[0026] S3, slow drainage: After the first nitrogen pipe continuously fills the IPA bubbling box with nitrogen for a set time, the first valve and the electromagnetic pump are opened, the ninth valve is closed, and the first drain pipe starts to drain slowly. The cleaning liquid in the first tank is discharged through the first section, the second section and the third section in sequence. When the liquid level of the cleaning liquid drops to the set height of the exposed wafer, the wafer chuck rotates to abut against the top of the multiple wafers, and cooperates with the wafer holder to constrain the posture and position of the multiple wafers. The lifting mechanism slowly descends to point D, and the multiple wafers are separated from the wafer box, and the wafers are The box is supported at the bottom of the wafer support. When the liquid level of the cleaning solution continues to drop below the wafer box, the eleventh valve is closed, the first nitrogen pipe stops filling nitrogen into the IPA bubbling box, the first valve and the electromagnetic pump are closed, the slow drainage of the first drain pipe stops, the air bag pump, the third valve, the fourth valve and the second valve are closed, the IPA stock solution barrel and the liquid storage tank stop injecting IPA solution into the IPA bubbling box, the fifth valve and the seventh valve are opened, and the IPA solution in the IPA bubbling box flows back to the liquid storage tank through the second pipeline;

[0027] S4, fast drainage: the first valve is closed, the ninth valve is opened, and the cleaning liquid is quickly discharged through the first section, the sixth pipe and the third section. The lifting mechanism rises to point C, the wafer chuck rotates back to its original position, and after all the cleaning liquid in the first tank is discharged, the ninth valve is closed after the set time has passed;

[0028] S5, wafer drying: the tenth valve is opened, the gas supply pipe and the second nitrogen pipe supply nitrogen to the multiple nitrogen nozzles of the slot cover, and the gas online heater is turned on at the same time to heat the nitrogen, so that the hot nitrogen sprayed from the multiple nitrogen nozzles dries the wafers and the wafer box. After the set drying time, the slot cover is opened, the lifting mechanism rises to point A, the gas online heater is turned off, the gas supply pipe and the second nitrogen pipe continue to supply nitrogen to the multiple nitrogen nozzles of the slot cover at a small flow rate, and the IPA solution in the IPA bubbling box is all refluxed to the liquid storage tank;

[0029] S6, process end: the tenth valve is closed, the gas supply pipe and the second nitrogen pipe stop supplying nitrogen to the multiple nitrogen nozzles of the tank cover, the tank cover is closed, the lifting mechanism rises to point B, the thirteenth valve is opened, the liquid inlet pipe slowly injects cleaning liquid into the first tank body, the wafer box on the lifting mechanism is removed, and after the liquid level of the cleaning liquid in the first tank body reaches the specified position, the twelfth valve is opened, and the cleaning liquid begins to be quickly injected into the first tank body through the liquid inlet pipe. After the liquid level of the cleaning liquid in the first tank body reaches the specified position, the twelfth valve is closed, and the liquid inlet pipe slowly injects cleaning liquid into the first tank body, so that the cleaning liquid in the first tank body is in a full water and slowly overflowing state;

[0030] The lifting height points of the lifting mechanism are from high to low: point B, point A, point C, and point D.

[0031] Compared with the prior art, this application has at least the following beneficial effects:

[0032] During the cleaning process of the wafer, the lifting mechanism lifts the wafer box carrying multiple wafers into the drying tank body, or takes it out of the drying tank body. When the wafer box and the wafer are immersed in the cleaning solution in the drying tank body and start cleaning, the IPA bubbling box injects isopropyl alcohol vapor into the drying tank body. At the same time, the cleaning solution in the drying tank body begins to be discharged through the first drain pipe, and the first valve is opened. The flow meter monitors the flow rate of the cleaning solution in the first drain pipe in real time, and feeds the data back to the controller. The controller automatically adjusts the flow rate of the electromagnetic pump according to the feedback information to achieve accurate control of the cleaning solution discharge speed. Compared with the prior art that requires manual adjustment of multiple valves to control the drainage speed, the present application adopts an automated control method, which can improve the convenience of operation, ensure the accuracy and stability of the discharge speed, avoid the errors caused by manual adjustment, and thus improve the cleaning effect and the stability of the subsequent drying process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more intuitively illustrate the prior art and the present application, several exemplary drawings are given below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing the present application; for example, those skilled in the art are capable of easily making conventional adjustments or further optimizations to the addition / reduction / attribution division, specific shapes, positional relationships, connection methods, dimensional ratios, etc. of certain units (components) based on the technical concepts and exemplary drawings disclosed in the present application.

[0034] Figure 1 A schematic diagram of a pipeline of a cleaning and drying structure assembly of a wafer dryer provided in one embodiment of the present application;

[0035] Figure 2 for Figure 1 A magnified image of point A;

[0036] Figure 3 for Figure 1 A magnified view of point B;

[0037] Figure 4 for Figure 1 Enlarged view of point C;

[0038] Figure 5 for Figure 1 The enlarged view of point D;

[0039] Figure 6 A partial structural schematic diagram of a wafer drying machine provided in one embodiment of the present application;

[0040] Figure 7 A schematic diagram of the cooperation between a drying tank and a lifting mechanism provided in one embodiment of the present application;

[0041] Figure 8 for Figure 7 Schematic diagram of some structures;

[0042] Fig. 9 A schematic diagram of the structure of a drying tank provided in one embodiment of the present application;

[0043] Fig.10 for Figure 6 Schematic diagram of some structures;

[0044] Fig.11 for Fig.10 Schematic diagram of some structures;

[0045] Fig.12 for Fig.11 Partial structural cross-sectional view along the aa direction.

[0046] Description of reference numerals:

[0047] 1. Drying tank body; 11. First tank body; 12. Second tank body; 121. Overflow tank; 13. IPA bubbling box; 14. Tank cover; 141. Nitrogen nozzle; 15. Wafer chuck; 16. Wafer holder; 2. Lifting mechanism; 3. Wafer box; 31. Wafer; 4. First drain pipe; 41. First section; 42. Second section; 421. First valve; 422. Solenoid pump; 423. Flow meter; 43. Third section; 44. Sixth pipeline; 441. Ninth valve; 5. Second drain pipe; 6. Liquid inlet pipe; 61. Seventh pipeline; 62. Thirteenth valve; 63. 12th valve; 7, first pipeline; 71, third pipeline; 711, sixth valve; 72, third valve; 73, bellows pump; 74, fourth valve; 75, fifth valve; 76, fifth pipeline; 761, eighth valve; 77, fourth pipeline; 771, seventh valve; 78, filter; 8, second pipeline; 81, second valve; 9, gas supply pipe; 91, first nitrogen pipe; 911, eleventh valve; 92, second nitrogen pipe; 921, tenth valve; 922, gas online heater; 10, liquid storage tank; 101, main body; 102, IPA stock solution barrel. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] In the description of this application: unless otherwise specified, "plurality" means two or more. The terms "first", "second", "third", etc. in this application are intended to distinguish the objects referred to, and do not have special meanings in terms of technical connotations (for example, they should not be understood as emphasizing the importance or order, etc.). Expressions such as "including", "comprising", "having", etc. also mean "not limited to" (certain units, components, materials, steps, etc.).

[0050] refer to Figure 1-7 The present application discloses a cleaning and drying structure assembly of a wafer dryer, the wafer dryer comprises a main body 101 and a lifting mechanism 2 connected to the main body 101 and used for lifting a wafer box 3, the cleaning and drying structure assembly comprises a drying tank body 1 connected to the main body 101, a liquid inlet pipe 6 connected to the drying tank body 1 and used for injecting a cleaning liquid into the drying tank body 1, an IPA bubbling box 13 connected to the drying tank body 1 and used for injecting isopropyl alcohol vapor into the drying tank body 1, a first liquid discharge pipe 4 connected to the drying tank body 1 and used for discharging the cleaning liquid in the drying tank body 1, and a controller connected to the main body 101;

[0051] The drying tank body 1 is connected to its groove with a groove cover 14 for sealing its groove;

[0052] The first liquid discharge pipe 4 is connected to an electromagnetic pump 422, a first valve 421 and a flow meter 423 for measuring the flow rate of liquid in the first liquid discharge pipe 4. The electromagnetic pump 422 and the flow meter 423 are both electrically connected to a controller so that the controller controls the flow rate of the electromagnetic pump 422 according to the signal feedback of the flow meter 423 on the flow rate of liquid in the first liquid discharge pipe 4.

[0053] During the cleaning process of the wafer 31, the lifting mechanism 2 lifts the wafer box 3 carrying multiple wafers 31 into the drying tank body 1, or takes it out of the drying tank body 1. When the wafer box 3 and the wafer 31 are immersed in the cleaning solution in the drying tank body 1 and start cleaning, the IPA bubbling box 13 injects isopropyl alcohol vapor into the drying tank body 1. At the same time, the cleaning solution in the drying tank body 1 starts to be discharged through the first drain pipe 4, and the first valve 421 is opened. The flow meter 423 monitors the flow rate of the cleaning solution in the first drain pipe 4 in real time, and feeds the data back to the controller. The controller automatically adjusts the flow of the electromagnetic pump 422 according to the feedback information to achieve accurate control of the cleaning solution discharge speed. Compared with the prior art, which requires manual adjustment of multiple valves to control the drainage speed, the present application adopts an automated control method, which can improve the convenience of operation, ensure the accuracy and stability of the discharge speed, avoid the error caused by manual adjustment, and thus improve the cleaning effect and the stability of the subsequent drying process.

[0054] It should be noted that the wafer dryer, lifting mechanism 2, electromagnetic pump, flow meter and controller are prior art and are not described in detail in this application. It should be added that slow drainage refers to the process of slowly lowering the liquid level in the drying tank 1 by accurately controlling the drainage speed. This control method can maintain an appropriate contact time between the liquid level and the surface of the wafer 31, and avoid excessively fast water flow affecting the cleaning effect.

[0055] In some embodiments, the controller may be a frequency converter.

[0056] refer to Figure 7-12 The drying tank body 1 includes a first tank body 11 connected to the main body 101 and a second tank body 12 connected to the top outer wall of the first tank body 11. The second tank body 12 and the outer wall of the first tank body 11 form an overflow tank 121 so that the cleaning liquid overflowing from the first tank body 11 flows into the overflow tank 121. The bottom of the overflow tank 121 is connected to a second drain pipe 5;

[0057] The liquid inlet pipe 6 is connected to the side wall of the first trough body 11, the first liquid discharge pipe 4 is connected to the bottom wall of the first trough body 11, the IPA bubbling box 13 is connected to the side wall of the second trough body 12, and the box opening of the IPA bubbling box 13 is higher than the slot opening of the first trough body 11, and the slot cover 14 is connected to the slot opening of the second trough body 12.

[0058] During the cleaning and drying process, the cleaning liquid is injected into the first tank body 11 through the liquid inlet pipe 6, gradually filling the entire tank body. When the liquid level of the cleaning liquid reaches the slot of the first tank body 11, the excess cleaning liquid will overflow into the overflow tank 121, thereby realizing the overflow discharge of the cleaning liquid in the first tank body 11, and the cleaning liquid in the overflow tank 121 is discharged through the second liquid discharge pipe 5. Through this design, the cleaning liquid in the first tank body 11 can be kept in a state of continuous flow and replacement, so as to effectively remove the suspended particles and impurities in the tank body and maintain the cleanliness of the liquid in the tank. In particular, when the tank cover 14 is opened, external particles or impurities in the air may enter the drying tank body 1, and this overflow discharge method can effectively discharge these particles and impurities from the overflow tank 121, preventing them from being retained in the drying tank body 1 and affecting the cleanliness and drying effect of the wafer 31.

[0059] In some embodiments, there are two IPA bubbling boxes 13 , and the two IPA bubbling boxes 13 are located on opposite sides of the second trough body 12 .

[0060] The side wall of the IPA bubbling box 13 is connected to a first nitrogen pipe 91 for filling nitrogen into the IPA bubbling box 13. Nitrogen bubbles in the IPA bubbling box 13 to evaporate the IPA solution into the drying tank body 1. The first nitrogen pipe 91 continuously fills nitrogen into the IPA bubbling box 13, and nitrogen forms bubbles in the IPA solution in the IPA bubbling box 13. The bubbles in the IPA liquid will continuously disturb the surface of the IPA liquid, thereby increasing the contact area between the IPA liquid and the air. This bubble disturbance accelerates the evaporation rate of IPA, and can generate and transmit IPA vapor to the drying tank body 1 more quickly, forming the required IPA gas environment in the drying tank body 1.

[0061] The main body 101 is connected to a liquid storage tank 10 for storing an IPA solution, the liquid storage tank 10 is connected to a first pipeline 7 for supplying an IPA solution to an IPA bubbling box 13, and the liquid storage tank 10 is also connected to a second pipeline 8 for discharging the IPA solution in the IPA bubbling box 13 back into the liquid storage tank 10. The main body 101 is externally connected to an IPA stock solution barrel 102, and a third pipeline 71 is connected between the IPA stock solution barrel 102 and the first pipeline 7 to replenish the IPA solution to the liquid storage tank 10;

[0062] The first pipe 7 and the second pipe 8 cooperate to maintain the liquid level in the IPA bubbling box 13 at a set height.

[0063] In the process that the IPA solution in the IPA bubbling box 13 gradually evaporates and enters the drying tank 1, the liquid level of the IPA solution will gradually decrease. In order to maintain the stability of the liquid level in the IPA bubbling box 13, the IPA stock solution barrel 102 supplies the IPA solution to the liquid storage tank 10 through the third pipeline 71, and the liquid storage tank 10 then replenishes the IPA solution to the IPA bubbling box 13 through the first pipeline 7, and the first pipeline 7 and the second pipeline 8 cooperate to form a circulation flow of the IPA solution in the liquid storage tank 10 and the IPA bubbling box 13, and maintain the liquid level of the IPA solution in the IPA bubbling box 13 at a preset height, ensuring that the liquid level of the IPA solution in the IPA bubbling box 13 is at an optimal height to produce an ideal bubbling effect.

[0064] The second pipeline 8 is connected to a second valve 81, and the first pipeline 7 is sequentially connected to a third valve 72, a wind bag pump 73, a fourth valve 74 and a fifth valve 75 from the liquid storage tank 10 to the IPA bubbling box 13. The third valve 72 is located between the liquid storage tank 10 and the third pipeline 71, the wind bag pump 73, the fourth valve 74 and the fifth valve 75 are located between the third pipeline 71 and the IPA bubbling box 13, and the third pipeline 71 is connected to a sixth valve 711;

[0065] A fourth pipeline 77 is connected between the first pipeline 7 and the liquid storage tank 10 , and a seventh valve 771 is connected to the fourth pipeline 77 . A filter 78 is connected to the first pipeline 7 , and a fifth pipeline 76 is connected between the filter 78 and the liquid storage tank 10 , and an eighth valve 761 is connected to the fifth pipeline 76 .

[0066] The second, third, fourth, fifth, sixth, seventh and eighth valves are used to control the opening and closing of the corresponding pipelines to achieve accurate management of the flow path of the IPA solution. The bellows pump 73 is used to control the flow rate of the IPA solution supplied to the IPA bubbling box 13.

[0067] In addition, a filter 78 is installed in the first pipeline 7 to filter impurities in the IPA solution to ensure that the IPA solution entering the IPA bubbling box 13 is clean. In order to prevent the gas accumulation in the filter 78 from affecting the filtering efficiency, the eighth valve 761 is designed to automatically open for 1 second every 5 seconds to discharge the gas accumulated in the filter 78 into the liquid storage tank 10, effectively preventing the filter 78 from being "stuck" due to gas accumulation.

[0068] The first liquid discharge pipe 4 includes a first section 41 connected to the first tank body 11, a second section 42 connected to an end of the first section 41 away from the first tank body 11, and a third section 43 connected to an end of the second section 42 away from the first section 41 and used to discharge the cleaning liquid in the first tank body 11 to the outside of the main body 101, an electromagnetic pump 422, a first valve 421 and a flow meter 423 are connected to the second section 42, the first liquid discharge pipe 4 is connected to a sixth pipe 44, one end of the sixth pipe 44 is connected to the intersection of the first section 41 and the second section 42, and the other end is connected to the intersection of the second section 42 and the third section 43, and the sixth pipe 44 is connected to a ninth valve 441.

[0069] During the cleaning and drying process, when the liquid level of the cleaning liquid in the first tank body 11 gradually drops below the wafer 31 and the wafer box 3, the slow drainage process stops. At this time, the controller turns off the electromagnetic pump 422 and the first valve 421 to terminate the slow drainage process of the first drain pipe 4. Then, the ninth valve 441 on the sixth pipe 44 is opened to allow the cleaning liquid in the first tank body 11 to quickly flow to the third section 43 through the first section 41 and the sixth pipe 44, and finally be discharged from the outside of the main body 101, so that the cleaning liquid can be quickly discharged from the first tank body 11, thereby saving time and improving the efficiency of cleaning and drying.

[0070] In some embodiments, one end of the second drain pipe 5 away from the second tank body 12 is connected to the third section 43 , so that the cleaning liquid in the overflow tank 121 can be discharged through the second drain pipe 5 and the third section 43 .

[0071] The highest point of the second section 42 is higher than the notch of the first slot body 11 .

[0072] Since the first drain pipe 4 is connected to the bottom of the first tank body 11, the cleaning liquid flows into the first drain pipe 4 under the action of gravity, which leads to unstable drainage rate: when the water level in the tank body is high, the drainage rate is fast; as the water level drops, the drainage rate gradually slows down. In order to solve this problem, the design of the present application raises part of the second section 42 of the first drain pipe 4 so that its highest point is higher than the notch of the first tank body 11. Through this design, the cleaning liquid will encounter the high point of the second section 42 during the discharge process, and this height difference can offset the direct effect of gravity on the drainage rate to a certain extent.

[0073] The inner diameter of the third section 43 gradually increases from one end close to the second section 42 to the tail end of the third section 43 .

[0074] At the beginning of slow drainage, since the first drain pipe 4 may be filled with cleaning liquid, a siphon phenomenon is formed, and the cleaning liquid will be quickly sucked out under the siphon effect without being controlled by the electromagnetic pump. This phenomenon will cause large fluctuations in the drainage speed, which will in turn affect the uniformity and effect of the drying process, and may cause poor drying problems on the surface of the wafer 31; to solve this problem, the inner diameter of the third section 43 in the design of the present application gradually increases from one end close to the second section 42 to the tail end. Through the design of gradually increasing the inner diameter, the liquid in the pipeline will not fill the entire pipeline cross-section during the drainage process, avoiding the formation of a siphon phenomenon.

[0075] One end of the first nitrogen pipe 91 away from the IPA bubbling box 13 is connected to a gas supply pipe 9 for providing nitrogen, a second nitrogen pipe 92 is connected between the gas supply pipe 9 and the tank cover 14, the tank cover 14 is connected to a plurality of nitrogen nozzles 141 connected to the second nitrogen pipe 92, the second nitrogen pipe 92 is connected to a tenth valve 921 and a gas online heater 922, and the first nitrogen pipe 91 is connected to an eleventh valve 911.

[0076] In the cleaning and drying structure of the present application, the second nitrogen pipe 92 delivers nitrogen to the multiple nitrogen nozzles 141 of the tank cover 14, and the nitrogen is heated by the gas online heater 922. After cleaning, the heated nitrogen is sprayed through the nozzle to the multiple wafers 31 and the surface of the wafer box 3 in the drying tank body 1, thereby heating and drying the wafers 31. The heated nitrogen can quickly take away the trace moisture remaining on the surface of the wafer 31, and can also effectively reduce the retention of moisture in the first tank body 11, ensuring that the drying process is thorough and without water marks.

[0077] In some embodiments, the gas supply pipe 9 can be connected to a valve, a flow controller, a filter 78, a flow meter 423, etc.

[0078] The liquid inlet pipe 6 is connected to a twelfth valve 63 , the liquid inlet pipe 6 is connected to a seventh pipeline 61 , the seventh pipeline 61 is connected to a thirteenth valve 62 in parallel with the twelfth valve 63 , and the diameter of the thirteenth valve 62 is smaller than that of the twelfth valve 63 .

[0079] The thirteenth valve 62 has a smaller diameter and is used to control slow water injection, so that it is used when the cleaning liquid needs to be slowly and steadily injected into the first tank body 11. This ensures that the cleaning liquid enters the tank body smoothly and avoids liquid level fluctuations caused by too fast water injection. Especially in sensitive cleaning or drying stages, the rate of liquid level rise can be effectively controlled. The twelfth valve 63 has a larger diameter and is used for fast water injection, so that the tank body can be quickly filled at the beginning of the cleaning cycle, shortening the preparation time and improving the cleaning efficiency. Through the combination of these two valves with different diameters, the present application realizes flexible control of the water injection rate, which can achieve fine control by slow water injection in specific cleaning steps, and can also improve efficiency by fast water injection in the system preparation stage.

[0080] The present application discloses a wafer dryer, comprising the cleaning and drying structure assembly of the wafer dryer as described above.

[0081] refer to Figure 1-12 The present application also discloses a wafer cleaning and drying process, comprising the following steps:

[0082] S1, standby state before the wafer 31 is cleaned: the thirteenth valve 62 is opened, the twelfth valve 63 is closed, the liquid inlet pipe 6 slowly injects cleaning liquid into the first tank body 11, the cleaning liquid in the first tank body 11 is in a full and slow overflow state, the overflowing cleaning liquid enters the overflow tank 121, and is discharged through the second liquid discharge pipe 5 and the third section 43, so that the cleaning liquid in the first tank body 11 is in a flowing state, and the residual particles in the first tank body 11 are removed, the lifting height of the lifting mechanism 2 is at point A, the tank cover 14 is in a closed state, the tenth valve 921 on the second nitrogen pipe 92 is opened, and the multiple nitrogen nozzles 141 on the tank cover 14 blow nitrogen into the drying tank body 1;

[0083] Before the wafer is cleaned, the liquid level of the IPA solution in the liquid storage tank 10 is detected. When the liquid level of the IPA solution is lower than the M liquid level (working liquid level), the air bag pump 73, the sixth valve 711, the fourth valve 74, and the seventh valve 771 need to be opened, and the IPA stock liquid barrel 102 replenishes the IPA solution in the liquid storage tank 10 until the liquid level reaches the M liquid level (working liquid level); at the same time, the liquid level of the cleaning liquid in the first tank body 11 is also detected to ensure that the liquid level of the cleaning liquid in the first tank body 11 is in a full tank state; and in order to ensure the subsequent nitrogen drying effect, the temperature at the nitrogen nozzle is detected. When the set temperature is not reached, the tenth valve 921 and the gas online heater 922 need to be opened to preheat the second nitrogen pipe 92.

[0084] S2, cleaning of wafers 31: the tenth valve 921 on the second nitrogen pipe 92 is closed, the multiple nitrogen nozzles 141 on the tank cover 14 stop blowing nitrogen into the drying tank body 1, the tank cover 14 is opened, the lifting mechanism 2 is lifted to point B, the wafer box 3 is placed on the lifting mechanism 2, and then the lifting mechanism 2 is lowered to point C, the multiple wafers 31 in the wafer box 3 are immersed in the cleaning liquid in the first tank body 11, and are held up by the wafer holder 16 in the drying tank body 1, and the tank cover 14 is closed; wherein the wafer holder 16 is a prior art, and during the process of the wafer box 3 descending, the wafer holder 16 can hold up the multiple wafers 31; the twelfth valve 63 on the liquid inlet pipe 6 is opened, the liquid inlet pipe 6 quickly injects cleaning liquid into the first tank body 11, the cleaning liquid in the first tank body 11 is in a full water and overflowing state, the fifth valve 75 and the second valve 81 are opened, and the storage The liquid tank 10 supplies the IPA solution to the IPA bubbling box 13 through the first pipe 7. When the liquid level of the IPA solution in the IPA bubbling box 13 is higher than the pipe mouth of the second pipe 8, the IPA solution in the IPA bubbling box 13 flows back to the liquid storage tank 10 through the second pipe 8. After that, the twelfth valve 63 and the thirteenth valve 62 are closed, the liquid inlet pipe 6 stops injecting the cleaning liquid into the first tank body 11, the eleventh valve 911 is opened, and the first nitrogen pipe 91 fills the IPA bubbling box 13 with nitrogen, so that the IPA solution in the IPA bubbling box 13 forms nitrogen bubbles, and the IPA is evaporated into the drying tank body 1; one end of the second pipe 8 connected to the IPA bubbling box 13 is flush with the liquid surface of the IPA solution in the IPA bubbling box 13 under the circulating flow state, so that the IPA solution can naturally overflow from the second pipe 8 into the liquid storage tank 10;

[0085] S3, slow drainage: after the first nitrogen pipe 91 continuously fills nitrogen into the IPA bubbling box 13 for a set time, the first valve 421 and the electromagnetic pump 422 are opened, the ninth valve 441 is closed, and the first drain pipe 4 starts to drain slowly, and the cleaning liquid in the first trough 11 is discharged through the first section 41, the second section 42 and the third section 43 in sequence. When the liquid level of the cleaning liquid drops to a set height (about 2 cm) of the exposed wafer 31, the wafer chuck 15 rotates to abut against the top of the plurality of wafers 31, and cooperates with the wafer holder 16 to constrain the posture and position of the plurality of wafers 31 to prevent the wafers 31 from shaking, and the lifting mechanism 2 slowly descends to point D, and the plurality of wafers 31 are separated from the wafer box 3, and the wafer box 3 is supported at the bottom of the wafer holder 16. When the liquid level of the cleaning liquid continues to drop to below the wafer box 3, the eleventh valve 911 is closed, and the first The nitrogen pipe 91 stops filling nitrogen into the IPA bubbling box 13, the first valve 421 and the electromagnetic pump 422 are closed, the slow drainage of the first drain pipe 4 stops, the air bag pump 73, the third valve 72, the fourth valve 74 and the second valve 81 are closed, the IPA stock solution barrel 102 and the liquid storage tank 10 stop injecting IPA solution into the IPA bubbling box 13, the fifth valve 75 and the seventh valve 771 are opened, and the IPA solution in the IPA bubbling box 13 flows back to the liquid storage tank 10 through the second pipe 8; wherein, the wafer chuck 15 is also a prior art; in some embodiments, the wafer 31 may also be fixed by the wafer holder 16 itself instead of being constrained by the wafer chuck 15; in some embodiments, the round box 3 may be tilted and supported at the bottom of the wafer holder 16, so that the round box 3 is not easy to accumulate cleaning liquid;

[0086] S4, fast drainage: the first valve 421 is closed, the ninth valve 441 is opened, so that the cleaning liquid is quickly discharged through the first section 41, the sixth pipe 44 and the third section 43, the lifting mechanism 2 rises to the C point, the wafer chuck 15 rotates back to its original position, and after all the cleaning liquid in the first tank 11 is discharged, after a set time has passed, the ninth valve 441 is closed;

[0087] S5, drying of wafer 31: the tenth valve 921 is opened, the gas supply pipe 9 and the second nitrogen pipe 92 supply nitrogen to the multiple nitrogen nozzles 141 of the slot cover 14, and the gas online heater 922 is turned on at the same time to heat the nitrogen, so that the hot nitrogen sprayed from the multiple nitrogen nozzles 141 dries the wafer 31 and the wafer box 3. After the set drying time, the slot cover 14 is opened, the lifting mechanism 2 rises to point A, the gas online heater 922 is turned off, the gas supply pipe 9 and the second nitrogen pipe 92 continue to supply nitrogen to the multiple nitrogen nozzles 141 of the slot cover 14 at a small flow rate, and the IPA solution in the IPA bubbling box 13 is all refluxed to the liquid storage tank 10;

[0088] S6, process ends: the tenth valve 921 is closed, the gas supply pipe 9 and the second nitrogen pipe 92 stop supplying nitrogen to the multiple nitrogen nozzles 141 of the tank cover 14, the tank cover 14 is closed, the lifting mechanism 2 rises to point B, the thirteenth valve 62 is opened, the liquid inlet pipe 6 slowly injects the cleaning liquid into the first tank body 11, the wafer box 3 on the lifting mechanism 2 is removed, and after the liquid level of the cleaning liquid in the first tank body 11 reaches the specified position, the twelfth valve 63 is opened, and the cleaning liquid begins to be quickly injected into the first tank body 11 through the liquid inlet pipe 6. After the liquid level of the cleaning liquid in the first tank body 11 reaches the specified position, the twelfth valve 63 is closed, and the liquid inlet pipe 6 slowly injects the cleaning liquid into the first tank body 11, so that the cleaning liquid in the first tank body 11 is in a full water and slowly overflowing state;

[0089] The lifting height points of the lifting mechanism 2 are, from high to low, point B, point A, point C, and point D.

[0090] The technical features of the above embodiments may be arbitrarily combined (as long as there is no contradiction in the combination of these technical features). To make the description concise, not all possible combinations of the technical features in the above embodiments are described; these embodiments that are not explicitly written should also be considered to be within the scope of this specification.

[0091] The above is a relatively specific and detailed description of the present application through general description and specific embodiments. It should be understood that, based on the technical concept of the present application, several conventional adjustments or further innovations can be made to these specific embodiments; however, as long as they do not deviate from the technical concept of the present application, the technical solutions obtained by these conventional adjustments or further innovations also fall within the scope of protection of the claims of the present application.

Claims

1. A cleaning and drying structure assembly of a wafer dryer, the wafer dryer comprising a main body and a lifting mechanism connected to the main body and used to lift a wafer box, characterized in that: The cleaning and drying structure assembly includes a drying tank body connected to the main body, a liquid inlet pipe connected to the drying tank body and used to inject cleaning liquid into the drying tank body, an IPA bubbling box connected to the drying tank body and used to inject isopropyl alcohol vapor into the drying tank body, a first liquid drain pipe connected to the drying tank body and used to discharge the cleaning liquid in the drying tank body, and a controller connected to the main body; The drying tank body is connected to its own notch with a tank cover for sealing its own notch; The first liquid discharge pipe is connected to an electromagnetic pump, a first valve and a flow meter for measuring the flow rate of liquid in the first liquid discharge pipe. The electromagnetic pump and the flow meter are both electrically connected to the controller so that the controller controls the flow rate of the electromagnetic pump based on the signal feedback from the flow meter on the flow rate of liquid in the first liquid discharge pipe.

2. The cleaning and drying structure assembly according to claim 1, characterized in that: The drying tank body comprises a first tank body connected to the main body and a second tank body connected to the top outer wall of the first tank body, the second tank body and the outer wall of the first tank body form an overflow tank, so that the cleaning liquid overflowing from the first tank body flows into the overflow tank, and the bottom of the overflow tank is connected to a second drain pipe; The liquid inlet pipe is connected to the side wall of the first trough body, the first liquid discharge pipe is connected to the bottom wall of the first trough body, the IPA bubbling box is connected to the side wall of the second trough body, and the box opening of the IPA bubbling box is higher than the notch opening of the first trough body, and the trough cover is connected to the notch opening of the second trough body.

3. The cleaning and drying structure assembly according to claim 2, characterized in that: A first nitrogen pipe for filling nitrogen into the IPA bubbling box is connected to the side wall of the IPA bubbling box, and the nitrogen is bubbled in the IPA bubbling box to evaporate the IPA solution into the drying tank body.

4. The cleaning and drying structure assembly according to claim 3, characterized in that: The main body is connected to a liquid storage tank for storing IPA solution, the liquid storage tank is connected to a first pipeline for supplying IPA solution to the IPA bubbling box, the liquid storage tank is also connected to a second pipeline for discharging the IPA solution in the IPA bubbling box back into the liquid storage tank, the main body is connected to an IPA stock solution barrel on the outside, and a third pipeline is connected between the IPA stock solution barrel and the first pipeline to replenish the IPA solution to the liquid storage tank; The first pipe and the second pipe cooperate to maintain the liquid level in the IPA bubbling box at a set height.

5. The cleaning and drying structure assembly according to claim 4, characterized in that: The second pipeline is connected to a second valve, the first pipeline is sequentially connected to a third valve, a wind bag pump, a fourth valve and a fifth valve from the liquid storage tank to the IPA bubbling box, the third valve is located between the liquid storage tank and the third pipeline, the wind bag pump, the fourth valve and the fifth valve are located between the third pipeline and the IPA bubbling box, and the third pipeline is connected to a sixth valve; A fourth pipeline is connected between the first pipeline and the liquid storage tank, the fourth pipeline is connected to a seventh valve, the first pipeline is connected to a filter, a fifth pipeline is connected between the filter and the liquid storage tank, and the fifth pipeline is connected to an eighth valve.

6. The cleaning and drying structure assembly according to claim 2, characterized in that: The first liquid discharge pipe includes a first section connected to the first trough body, a second section connected to an end of the first section away from the first trough body, and a third section connected to an end of the second section away from the first section and used to discharge the cleaning liquid in the first trough body to the outside of the main body, the electromagnetic pump, the first valve and the flow meter are connected to the second section, the first liquid discharge pipe is connected to a sixth pipeline, one end of the sixth pipeline is connected to the intersection of the first section and the second section, and the other end is connected to the intersection of the second section and the third section, and the sixth pipeline is connected to a ninth valve.

7. The cleaning and drying structure assembly according to claim 6, characterized in that: The highest point of the second section is higher than the notch of the first slot body.

8. The cleaning and drying structure assembly according to claim 6, characterized in that: The inner diameter of the third section gradually increases from one end close to the second section to the tail end of the third section.

9. The cleaning and drying structure assembly according to claim 3, characterized in that: An end of the first nitrogen pipe away from the IPA bubbling box is connected to a gas supply pipe for providing nitrogen, a second nitrogen pipe is connected between the gas supply pipe and the tank cover, the tank cover is connected to a plurality of nitrogen nozzles connected to the second nitrogen pipe, the second nitrogen pipe is connected to a tenth valve and a gas online heater, and the first nitrogen pipe is connected to an eleventh valve.

10. The cleaning and drying structure assembly according to claim 2, characterized in that: The liquid inlet pipe is connected to a twelfth valve, the liquid inlet pipe is connected to a seventh pipeline, the seventh pipeline is connected to a thirteenth valve in parallel with the twelfth valve, and the diameter of the thirteenth valve is smaller than the diameter of the twelfth valve.

11. A wafer drying machine, characterized in that: A cleaning and drying structure assembly comprising a wafer dryer according to any one of claims 1-10.

12. A wafer cleaning and drying process, characterized in that: The following steps are involved: S1, standby state before wafer cleaning: the thirteenth valve is opened, the twelfth valve is closed, the liquid inlet pipe slowly injects cleaning liquid into the first tank body, the cleaning liquid in the first tank body is in a full and slow overflow state, the overflowing cleaning liquid enters the overflow tank, and is discharged through the second liquid discharge pipe and the third section, the lifting height of the lifting mechanism is at point A, the tank cover is in a closed state, the tenth valve on the second nitrogen pipe is opened, and multiple nitrogen nozzles on the tank cover blow nitrogen into the drying tank body; S2, wafer cleaning: the tenth valve on the second nitrogen pipe is closed, the multiple nitrogen nozzles on the tank cover stop blowing nitrogen into the drying tank body, the tank cover is opened, the lifting mechanism is lifted to point B, the wafer box is placed on the lifting mechanism, the lifting mechanism is lowered to point C, the multiple wafers in the wafer box are immersed in the cleaning liquid in the first tank body, and are held up by the wafer holder in the drying tank body, and the tank cover is closed; the twelfth valve on the liquid inlet pipe is opened, the liquid inlet pipe quickly injects cleaning liquid into the first tank body, the cleaning liquid in the first tank body is full and about to overflow, and the fifth valve is opened The twelfth and thirteenth valves are closed, the liquid inlet pipe stops injecting cleaning liquid into the first tank body, the eleventh valve is opened, and the first nitrogen pipe fills nitrogen into the IPA bubbling box, so that the IPA solution in the IPA bubbling box forms nitrogen bubbles, and the IPA is evaporated into the drying tank body; S3, slow drainage: After the first nitrogen pipe continuously fills the IPA bubbling box with nitrogen for a set time, the first valve and the electromagnetic pump are opened, the ninth valve is closed, and the first drain pipe starts to drain slowly. The cleaning liquid in the first tank is discharged through the first section, the second section and the third section in sequence. When the liquid level of the cleaning liquid drops to the set height of the exposed wafer, the wafer chuck rotates to abut against the top of the multiple wafers, and cooperates with the wafer holder to constrain the posture and position of the multiple wafers. The lifting mechanism slowly descends to point D, and the multiple wafers are separated from the wafer box, and the wafers are The box is supported at the bottom of the wafer support. When the liquid level of the cleaning solution continues to drop below the wafer box, the eleventh valve is closed, the first nitrogen pipe stops filling nitrogen into the IPA bubbling box, the first valve and the electromagnetic pump are closed, the slow drainage of the first drain pipe stops, the air bag pump, the third valve, the fourth valve and the second valve are closed, the IPA stock solution barrel and the liquid storage tank stop injecting IPA solution into the IPA bubbling box, the fifth valve and the seventh valve are opened, and the IPA solution in the IPA bubbling box flows back to the liquid storage tank through the second pipeline; S4, fast drainage: the first valve is closed, the ninth valve is opened, and the cleaning liquid is quickly discharged through the first section, the sixth pipe and the third section. The lifting mechanism rises to point C, the wafer chuck rotates back to its original position, and after all the cleaning liquid in the first tank is discharged, the ninth valve is closed after the set time has passed; S5, wafer drying: the tenth valve is opened, the gas supply pipe and the second nitrogen pipe supply nitrogen to the multiple nitrogen nozzles of the slot cover, and the gas online heater is turned on at the same time to heat the nitrogen, so that the hot nitrogen sprayed from the multiple nitrogen nozzles dries the wafers and the wafer box. After the set drying time, the slot cover is opened, the lifting mechanism rises to point A, the gas online heater is turned off, the gas supply pipe and the second nitrogen pipe continue to supply nitrogen to the multiple nitrogen nozzles of the slot cover at a small flow rate, and the IPA solution in the IPA bubbling box is all refluxed to the liquid storage tank; S6, process end: the tenth valve is closed, the gas supply pipe and the second nitrogen pipe stop supplying nitrogen to the multiple nitrogen nozzles of the tank cover, the tank cover is closed, the lifting mechanism rises to point B, the thirteenth valve is opened, the liquid inlet pipe slowly injects cleaning liquid into the first tank body, the wafer box on the lifting mechanism is removed, and after the liquid level of the cleaning liquid in the first tank body reaches the specified position, the twelfth valve is opened, and the cleaning liquid begins to be quickly injected into the first tank body through the liquid inlet pipe. After the liquid level of the cleaning liquid in the first tank body reaches the specified position, the twelfth valve is closed, and the liquid inlet pipe slowly injects cleaning liquid into the first tank body, so that the cleaning liquid in the first tank body is in a full water and slowly overflowing state; The lifting height points of the lifting mechanism are from high to low: point B, point A, point C, and point D.

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