Semiconductor wet cleaning equipment and self-cleaning method thereof

Abstract

The invention discloses semiconductor wet cleaning equipment and a self-cleaning method thereof, and relates to the field of semiconductors. Semiconductor wet cleaning equipment comprises a cavity, a bearing device, a protective cover and a self-cleaning device. The bearing device and the protective cover are both arranged in the cavity, the protective cover is arranged on the outer side of the bearing device in a surrounding mode, the protective cover comprises multiple layers of recycling cavities which are arranged in the axial direction of the cavity and used for recycling process liquid, and a gap is formed between every two adjacent recycling cavities; the self-cleaning device comprises a liquid inlet assembly and a spraying assembly, the spraying assembly is arranged in the gap, and the liquid inlet assembly is connected with the spraying assembly and used for conveying a cleaning medium to the spraying assembly and spraying the cleaning medium to the gap through the spraying assembly. The problems that the technological process is affected and wafers are damaged due to accumulation of the liquid medicine in the gaps of the recovery layers can be solved at least.

Description

Technical Field

[0001] The present application belongs to the field of semiconductors, and specifically relates to a semiconductor wet cleaning device and a self-cleaning method thereof. Background Art

[0002] In the process of integrated circuit manufacturing, wet cleaning is a very important surface treatment method, accounting for about 30% of the process. With the advancement of semiconductor chip manufacturing technology, the current mainstream cleaning equipment is single-wafer cleaning equipment. Compared with the tank type, the process chamber of a single chip is narrower and the internal structure is more complex. With the promotion of the single-wafer cleaning machine in the entire process, it will be exposed to different types, different functions, and different temperatures of liquid medicine. Under this background, the market has more and higher requirements for the interior of the single-wafer cleaning machine chamber.

[0003] For liquid chemicals that are easy to evaporate, have high process temperatures, and are easy to splash, a protective cover can be installed in the process chamber to collect the liquid chemicals. However, during the process, the liquid chemicals are easily accumulated in the protective cover, affecting the normal process and causing damage to the wafer. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a semiconductor wet cleaning device and a self-cleaning method thereof, which can at least solve the problems of liquid accumulation in the protective cover affecting the process and causing damage to the wafer.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] The embodiment of the present application provides a semiconductor wet cleaning device, comprising: a chamber, a carrying device, a protective cover and a self-cleaning device;

[0007] The carrying device and the protective cover are both arranged in the cavity, the protective cover is arranged around the outside of the carrying device, and the protective cover includes a multi-layer recovery chamber arranged along the axial direction of the cavity and used to recover the process liquid, and there is a gap between two adjacent recovery chambers;

[0008] The self-cleaning device comprises a liquid inlet assembly and a spray assembly. The spray assembly is arranged in the gap. The liquid inlet assembly is connected to the spray assembly and is used to transport a cleaning medium to the spray assembly and spray the cleaning medium to the gap through the spray assembly.

[0009] The embodiment of the present application also provides a self-cleaning method for a semiconductor wet cleaning device, which is applied to the above-mentioned semiconductor wet cleaning device, and the self-cleaning method includes:

[0010] The spray assembly disposed in the gap is used to spray a cleaning medium to the gap, so that pollutants accumulated in the gap are cleaned by the cleaning medium.

[0011] In an embodiment of the present application, a cleaning medium is transported to a spray assembly through a liquid inlet assembly, and the cleaning medium is sprayed into the gap between the recovery chambers of the protective cover through the spray assembly, so that pollutants accumulated in the gap are cleaned away by the cleaning medium, thereby effectively alleviating the problem of pollutants accumulating in the gap and causing the gap to be blocked, reducing or even eliminating the impact of the gap blockage on the flow field on the wafer surface, alleviating the problem of particle contamination, and also alleviating the problem of structural hardware being corroded by pollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of a protective cover and a process chuck in the related art;

[0013] Figure 2 A schematic diagram of the structure of the protective cover, the carrying device and the self-cleaning device disclosed in the embodiment of the present application;

[0014] Figure 3 A schematic diagram of the structure of a part of the protective cover and the spray chamber disclosed in the embodiment of the present application;

[0015] Figure 4 A top view of the spray chamber disclosed in the embodiment of the present application;

[0016] Figure 5 It is a cross-sectional schematic diagram of the spray chamber disclosed in the embodiment of the present application;

[0017] Figure 6 It is a schematic diagram of the structure of the spray chamber disclosed in the embodiment of the present application;

[0018] Figure 7 This is a flow chart of a first implementation of the self-cleaning method disclosed in an embodiment of the present application;

[0019] Figure 8 This is a flow chart of a second embodiment of the self-cleaning method disclosed in an embodiment of the present application;

[0020] Fig. 9 This is a flow chart of a third embodiment of the self-cleaning method disclosed in the examples of the present application;

[0021] Fig.10 This is a specific flow chart of the self-cleaning method disclosed in the embodiments of the present application.

[0022] Description of reference numerals:

[0023] 01-process chuck; 02-process chuck protection cover; 021-liquid recovery layer; 022-gap;

[0024] 100-self-cleaning device;

[0025] 110-liquid inlet assembly; 111-liquid inlet branch pipe; 112-air inlet branch pipe; 113-liquid inlet main pipe; 114-water mist generator; 115-nozzle; 116-first control valve; 117-second control valve; 118-first flow detection element; 119-second flow detection element;

[0026] 120-spray assembly; 121-spray chamber; 1211-inclined top wall; 1212-inclined bottom wall; 1213-inner annular wall; 1214-outer annular wall; 122-inlet; 123-grid hole;

[0027] 130-liquid discharge assembly; 131-liquid discharge box; 132-liquid discharge main pipe; 133-gas-liquid separator; 134-waste gas branch pipe; 135-waste liquid branch pipe;

[0028] 200-protective cover; 210-recovery chamber; 220-gap;

[0029] 300-Carrying device. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0032] The embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0033] For liquid chemicals that are easy to evaporate, have high process temperatures, and are prone to splashing, it is necessary to clean the process chamber. Figure 1, process chuck 01, robot arm, nozzle, process chuck protection cover 02, etc. In the current equipment, the vapor of the chemical liquid will gather and crystallize in the gap 022 between the chemical liquid recovery layer 021 during the process, such as BOE (HF, NH4F, H2O), ACT NE-111 (finished acid, AlIC Clean), NH4F, etc. These crystals may fall on the surface of the process chuck 01 as the chamber moves, blocking the opening of the clamping needle, making the opening and closing functions of the process chuck 01 abnormal, and causing wafer damage in severe cases. In addition, if crystals fall off during the process, a large number of particles will be generated, causing serious process problems; the liquid will remain in the gap 022 after splashing. Similarly, such as TMAH (tetramethylammonium hydroxide, mostly used for chemical mechanical polishing), REZi-38 (finished acid, Al / CU stripping liquid), SPM (H2SO4, H2O2, H2O mixture), etc., when this liquid splashes into the gap 022, it will corrode the hardware and reduce the service life of the hardware over time. When it is blocked to a certain extent, it may affect the flow field on the wafer surface, causing micro-environment damage and particle pollution.

[0034] To solve the above problems, an embodiment of the present application discloses a semiconductor wet cleaning device, which is used to perform process processing on wafers, wherein the semiconductor wet cleaning device can perform a wet cleaning process on the wafer, that is, a wet etching process, etc.

[0035] refer to Figures 2 to 10 The disclosed semiconductor wet cleaning equipment includes a chamber, a carrier device 300 , a protective cover 200 and a self-cleaning device 100 .

[0036] The cavity is a basic component, which can provide a storage space for the carrier 300, the protective cover 200, the self-cleaning device 100, etc., and can also provide a sealed environment for process treatment (such as wet cleaning process, etc.). The carrier 300 is used to carry the wafer, and the protective cover 200 is used to play a protective role.

[0037] For process treatment, the semiconductor wet cleaning equipment may also include a chemical liquid spraying device and an ultrapure water spraying device (not shown in the figure) to spray chemical liquid or ultrapure water onto the carrier device 300 and the wafer respectively during the process to meet the process requirements during the wet etching process.

[0038] In the actual process (such as wet cleaning or wet etching, etc.), the wafer is placed on the carrier 300, and the carrier 300 carries the wafer for rotation, and the process liquid is sprayed on the wafer surface by the liquid spray device, and the ultrapure water is sprayed on the wafer surface by the ultrapure water spray device, so as to remove impurities on the wafer surface or etch the thin film layer (such as silicon nitride layer, etc.) on the wafer surface, thereby improving the quality of the prepared product. In addition, the rotation of the wafer carried by the carrier 300 can make the process liquid and ultrapure water sprayed more evenly on the wafer surface, further improve the uniformity of the process treatment, and improve the product yield. In addition, during the process, the process liquid can be collected by the protective cover 200 to prevent the process liquid from splashing at will.

[0039] In some embodiments, the carrier 300 and the protective cover 200 are both disposed in the cavity, and the protective cover 200 is disposed around the carrier 300, so that the process liquid can be collected around the carrier 300 through the protective cover 200. The protective cover 200 may include a multi-layer recovery chamber 210 arranged along the axial direction of the cavity, the multi-layer recovery chamber 210 is used to recover the process liquid, and a gap 220 is provided between two adjacent recovery chambers 210.

[0040] Based on the above arrangement, multiple layers of recovery chambers 210 can be formed in the cavity, respectively surrounding the outside of the carrier device 300, so that the process liquid thrown out during the rotation of the carrier device 300 can be recovered to prevent the process liquid from randomly splashing and causing pollution or damage to the cavity. Considering that the protective cover 200 includes multiple layers of recovery chambers 210, the multiple layers of recovery chambers 210 are stacked and arranged so that a gap 220 is formed between two adjacent layers of recovery chambers 210. Due to the existence of the gap 220, the gas generated by the evaporation of the process liquid during the process will enter the gap 220 and deposit. If the cleaning is not timely or in place, the process liquid will crystallize in the gap 220, especially the crystals often gather near the edge of the gap 220. In the long run, it will affect the normal use of the cavity or corrode the hardware; in addition, if the crystals fall accidentally, it will also cause the cavity to be contaminated, affecting the product yield.

[0041] Based on the above situation, the semiconductor wet cleaning equipment in the embodiment of the present application includes a self-cleaning device 100, which includes a liquid inlet component 110 and a spray component 120, wherein the spray component 120 is arranged in the gap 220, and the liquid inlet component 110 is connected to the spray component 120, which is used to transport the cleaning medium to the spray component 120, and spray the cleaning medium to the gap 220 through the spray component 120, so as to clean away the contaminants in the gap 220 through the cleaning medium.

[0042] Based on the above-mentioned configuration, in the embodiment of the present application, the cleaning medium is transported to the spray assembly 120 through the liquid inlet assembly 110, and the cleaning medium is sprayed into the gap 220 between the recovery chamber 210 of the protective cover 200 through the spray assembly 120, so that the pollutants accumulated in the gap 220 are cleaned away by the cleaning medium, thereby effectively alleviating the problem of the gap 220 being blocked due to the accumulation of pollutants in the gap 220, reducing or even eliminating the influence of the blockage of the gap 220 on the flow field on the wafer surface, alleviating the problem of particle contamination, and also alleviating the problem of structural hardware being corroded by pollutants.

[0043] In some embodiments, the spray assembly 120 may include a spray cavity 121, the spray cavity 121 is provided with an inlet 122, the liquid inlet assembly 110 is connected to the inlet 122, and the spray cavity 121 may be provided with a grid hole 123, and the inner cavity of the spray cavity 121 is connected to the gap 220 through the grid hole 123. The grid hole 123 can block the cleaning medium in the spray cavity 121 to a certain extent, so as to prevent the cleaning medium from directly diffusing downward after entering from the inlet 122, thereby effectively alleviating the problem of uneven cleaning effect caused by the direct downward diffusion of the cleaning medium; in addition, the grid hole 123 can also play a role in uniformly diffusing the cleaning medium, so as to improve the uniformity of the cleaning medium spraying.

[0044] Based on the above configuration, the liquid inlet component 110 can transport the cleaning medium to the spray chamber 121 via the inlet 122, and the cleaning medium in the spray chamber 121 can be sprayed into the gap 220 via the grid hole 123. By setting the grid hole 123, the spraying area of ​​the cleaning medium can be increased, and the cleaning medium can be diffused, so that the gap 220 can be cleaned in all directions, and the uniformity of the cleaning effect can be improved, thereby improving the cleaning effect of the gap 220, and effectively preventing the process liquid from accumulating and crystallizing in the gap 220.

[0045] It should be noted that the mesh density of the mesh holes 123 should not be too low, because too low a mesh density will result in the spray chamber 121 not being able to store the cleaning medium; of course, the mesh density should not be too high, because too high a mesh density will result in excessive pressure in the spray chamber 121. Therefore, when designing the mesh density, it is necessary to refer to the delivery pressure of the cleaning medium and the spray pressure.

[0046] Considering that the protective cover 200 is arranged around the outside of the supporting device 300, the multiple layers of recovery chambers 210 are all annular chambers, and an annular gap is formed between two adjacent layers of recovery chambers 210, and the annular gap gradually extends downward from the center line of the protective cover 200 to the edge direction.

[0047] In order to adapt to the gap 220, the spray cavity 121 can be an annular cavity, and in the axial direction of the cavity, the cross-sectional area of ​​the first end opening of the spray cavity 121 is smaller than the cross-sectional area of ​​the second end opening. Based on this configuration, the spray cavity 121 of this shape can adapt to the shape of the gap 220, so as to perform all-round spray cleaning on the gap 220 and ensure uniform cleaning effect at all locations of the gap 220.

[0048] In some embodiments, the spray chamber 121 may include an inclined top wall 1211, an inner annular wall 1213, an inclined bottom wall 1212, and an outer annular wall 1214 connected in sequence, wherein the inclined top wall 1211 is connected to the top of the gap 220, the inclined bottom wall 1212 is spaced apart from the bottom of the gap 220, and the grid holes 123 are distributed on the inclined bottom wall 1212, and the inlet 122 is opened on the inclined top wall 1211. Based on this arrangement, the cleaning medium can enter through the top of the spray chamber 121, and spray to the bottom of the gap 220 through the grid holes 123 at the inclined bottom wall 1212 under the action of gravity, and finally flow out obliquely downward along the gap 220, and take the pollutants out of the gap 220, so as to clean the gap 220 and ensure the cleanliness of the gap 220.

[0049] In addition, the cleaning medium is sprayed from top to bottom into the gap 220 through the spray cavity 121, so that the structure is relatively simple, the stability is strong, and the flow rate and angle requirements of the cleaning medium are relatively low.

[0050] Exemplarily, the spray cavity 121 is in a trapezoidal ring shape as a whole, and the cross section can be a parallelogram. The spray cavity 121 of this shape can adapt to the shape of the gap 220, and is convenient for fitting to the top surface of the gap 220, and the inclination angle is consistent with the top surface.

[0051] Furthermore, the inlet 122 can be located in the area of ​​the inclined top wall 1211 close to the inner annular wall 1213, and the inlet 122 and the inner annular wall 1213 are arranged opposite to each other. Based on this design, the cleaning medium entering the spray cavity 121 through the inlet 122 first collides with the inner annular wall 1213, and then turns back and flows obliquely downward along the spray cavity 121, so that the cleaning medium can flow obliquely from top to bottom through the inclined bottom wall 1212, and then can be more evenly sprayed from the grid holes 123 into the gap 220, which can improve the spraying uniformity of the cleaning medium to a certain extent, so as to improve the uniformity of the cleaning effect on the gap 220.

[0052] Exemplarily, the axis of the inlet 122 extends in the horizontal direction. This design allows the cleaning medium to enter the spray cavity 121 in the horizontal direction and be blocked by the inner annular wall 1213 and diffuse in the spray cavity 121, thereby improving the diffusion effect of the cleaning medium in the spray cavity 121.

[0053] In some embodiments, the liquid inlet assembly 110 may include a liquid inlet branch pipe 111, an air inlet branch pipe 112, a liquid inlet main pipe 113, a water mist generator 114 and a nozzle 115, wherein the liquid inlet branch pipe 111 and the air inlet branch pipe 112 are respectively connected to the input end of the water mist generator 114, the liquid inlet main pipe 113 is connected to the output end of the water mist generator 114, and the nozzle 115 is connected to one end of the liquid inlet main pipe 113 away from the water mist generator 114, and is connected to the spray assembly 120. Based on this configuration, liquid cleaning medium and gas can be respectively transported to the water mist generator 114 through the liquid inlet branch pipe 111 and the air inlet branch pipe 112, and a water mist cleaning medium is generated after being processed by the water mist generator 114. The water mist cleaning medium is transported to the nozzle 115 through the liquid inlet main pipe 113, and is sprayed toward the spray assembly 120 by the nozzle 115, and finally sprayed toward the gap 220 by the spray assembly 120, and the gap 220 is cleaned by the water mist cleaning medium.

[0054] Specifically, the nozzle 115 can be connected to the inlet 122 of the spray cavity 121, so that the water mist cleaning medium enters the spray cavity 121 through the inlet 122 and fills the spray cavity 121, and is finally sprayed to the gap 220 through the grid holes 123 to achieve a cleaning effect on the gap 220.

[0055] Exemplarily, the nozzle 115 may be a water mist nozzle, and the water mist sprayed by the water mist nozzle is closer to the gas, so that the water mist cleaning medium can fill the entire spray cavity 121; in addition, the gas introduced into the air intake branch pipe 112 may be an inert gas, such as nitrogen.

[0056] Based on the above settings, the pollutants in the gap 220 are cleaned by a water mist cleaning medium, which can increase the contact area between the cleaning medium and the gap 220 and extend the contact time between the cleaning medium and the pollutants, thereby improving the cleaning efficiency and cleaning effect to a certain extent; and, the uniformity of the distribution of the cleaning medium in the gap 220 can be improved, so that the cleaning medium fills the space within the entire gap 220, thereby improving the uniformity of the cleaning effect to a certain extent.

[0057] In addition, the liquid inlet assembly 110 may also include a first control valve 116, a second control valve 117, a first flow detection element 118, and a second flow detection element 119, wherein the first control valve 116 and the first flow detection element 118 are both arranged in the liquid inlet branch pipe 111, and the first control valve 116 is electrically connected to the first flow detection element 118; the second control valve 117 and the second flow detection element 119 are both arranged in the air inlet branch pipe 112, and the second control valve 117 is electrically connected to the second flow detection element 119. Based on this arrangement, the flow of the liquid cleaning medium in the liquid inlet branch pipe 111 can be detected in real time by the first flow detection element 118, and the flow can be controlled in real time by the first control valve 116 according to actual needs, and the flow of the gas in the air inlet branch pipe 112 can be detected in real time by the second flow detection element 119, and the flow can be controlled by the second control valve 117 according to actual needs.

[0058] For example, to achieve a predetermined atomization effect, the flow rate of the liquid cleaning medium may be set to no less than 200 ml / min, and the gas flow rate may be set to no less than 60 L / min. Of course, other ranges are possible and are not specifically limited here.

[0059] It should be noted here that in order to form a water mist cleaning medium, it is necessary to control the flow rates of the liquid cleaning medium and the gas introduced into the water mist generator 114. For example, the flow rate of the liquid cleaning medium is 200ml / min to 300ml / min, and the flow rate of nitrogen is 60L / min. Assuming that the flow rate of nitrogen remains unchanged, when the first flow detection element 118 detects that the flow rate of the liquid cleaning medium in the liquid inlet branch 111 is lower than 200ml / min, the liquid content in the water mist cleaning medium is too low, resulting in incomplete cleaning within the preset time, and the cleaning time needs to be extended, affecting the efficiency of the cleaning process; when the first flow detection element 118 detects that the flow rate of the liquid cleaning medium in the liquid inlet branch 111 is higher than 300ml / min, the liquid content in the water mist cleaning medium is too high, resulting in the cleaning medium only being able to clean part of the area, thereby resulting in incomplete cleaning of pollutants. Therefore, a signal is sent to the first control valve 116 through the first flow detection element 118, so that the flow of the liquid cleaning medium in the liquid inlet branch pipe 111 can be increased or decreased by adjusting the first control valve 116, thereby ensuring that the flow of the liquid cleaning medium is appropriate.

[0060] Of course, when the flow rate of the liquid cleaning medium remains unchanged, the second control valve 117 can also be controlled to adjust according to the second flow detection element 119 detecting that the flow rate of the gas in the intake branch pipe 112 is too large or too small, so as to reduce or increase the gas flow in the intake branch pipe 112 through the adjustment of the second control valve 117, thereby ensuring the appropriate gas flow rate.

[0061] Exemplarily, the first flow detection element 118 and the second flow detection element 119 can both be flow meters, and of course they can also be other components, which are not specifically limited here. In addition, the first control valve 116 and the second control valve 117 can both be pneumatic valves, and of course they can also be other types of valve bodies, which are not specifically limited here.

[0062] To further improve the uniformity of cleaning, the spray assembly 120 may include an annular spray cavity 121 (i.e., the annular cavity mentioned above), the spray cavity 121 is provided with a plurality of inlets 122, and the plurality of inlets 122 are evenly arranged along the circumference of the spray cavity 121. Accordingly, the liquid inlet assembly 110 may include a plurality of nozzles 115, and the plurality of nozzles 115 are connected to the plurality of inlets 122 in a one-to-one correspondence. Based on this arrangement, the water mist cleaning medium may be sprayed into the plurality of inlets 122 through the plurality of nozzles 115, thereby improving the uniformity of diffusion of the water mist cleaning medium in the spray cavity 121, thereby facilitating the water mist cleaning medium to be sprayed into the gap 220 through the mesh holes 123, thereby improving the cleaning effect.

[0063] For example, the liquid inlet assembly 110 may include three nozzles 115, and accordingly, the spray chamber 121 may be provided with three inlets 122, and the three nozzles 115 and the three inlets 122 are evenly arranged, respectively, so as to further improve the uniformity of diffusion of the water mist cleaning medium in the spray chamber 121. Of course, other numbers are also possible, which are not specifically limited here.

[0064] In order to prevent the cleaning medium carrying contaminants from flowing into the cavity and causing contamination in the cavity, the self-cleaning device 100 can also include a drainage component 130, which can collect the cleaning medium flowing out of the gap 220 and discharge it outside the cavity to prevent the cleaning medium carrying contaminants from accumulating in the cavity and causing contamination.

[0065] The drain assembly 130 may include a drain box 131, a drain main pipe 132, a gas-liquid separator 133, a waste gas branch pipe 134 and a waste liquid branch pipe 135, wherein the drain box 131 is located below the protective cover 200, and is used to receive the cleaning medium flowing out through the gap 220, the drain main pipe 132 is connected between the drain box 131 and the input end of the gas-liquid separator 133, and the waste gas branch pipe 134 and the waste liquid branch pipe 135 are respectively connected to the output end of the gas-liquid separator 133. Based on this configuration, after cleaning the gap 220, the cleaning medium carries the pollutants out of the gap 220 and falls into the drain box 131, and is then transported to the gas-liquid separator 133 via the drain main pipe 132 for gas-liquid separation. The waste gas formed after the gas-liquid separation can be transported to a designated location (such as a waste gas treatment plant) via the waste gas branch pipe 134, and the waste liquid can be transported to another designated location (such as a waste liquid treatment plant) via the waste liquid branch pipe 135. Therefore, it is possible to avoid the cleaning medium carrying pollutants from polluting the cavity, and it is also possible to avoid the waste gas and waste liquid from polluting the external environment.

[0066] Based on the above configuration, an embodiment of the present application further discloses a self-cleaning method for semiconductor wet cleaning equipment, which is applied to the above semiconductor wet cleaning equipment.

[0067] refer to Figures 2 to 10 , the disclosed self-cleaning method comprises:

[0068] 701. Use the spray assembly 120 disposed in the gap 220 to spray a cleaning medium into the gap 220, so as to clean the pollutants accumulated in the gap 220 with the cleaning medium.

[0069] Based on the above steps, the gap 220 of the protective cover 200 can be cleaned by a cleaning medium to clean out pollutants in the gap 220 and ensure the cleanliness of the gap 220 .

[0070] Optionally, the liquid inlet assembly 110 may include a water mist generator 114;

[0071] Self-cleaning methods include:

[0072] 801 . The pollutants accumulated in the gap 220 are cleaned by using a water mist cleaning medium generated by the water mist generator 114 and sprayed into the gap 220 via the spray assembly 120 .

[0073] Compared with liquid cleaning, the water mist cleaning method adopted in the embodiment of the present application can be beneficial to the diffusion of the cleaning medium and improve the uniformity of spraying the cleaning medium into the gap 220, thereby improving the uniformity of the cleaning effect.

[0074] Further, the water mist generator 114 generates a water mist cleaning medium, including:

[0075] 8011. Cleaning medium and gas are introduced into the water mist generator 114 according to a preset flow ratio, so as to generate water mist cleaning medium through the water mist generator 114.

[0076] Specifically, the flow rates of the cleaning medium and the gas are detected respectively;

[0077] The flow rate of at least one of the cleaning medium and the gas is adjusted so that the cleaning medium and the gas are respectively delivered to the water mist generator 114 according to a preset flow rate ratio.

[0078] refer to Fig.10 , the process of the self-cleaning method in the embodiment of the present application is:

[0079] Step 1001, start;

[0080] Step 1002, detecting whether there is a wafer in the chamber for processing, if yes, executing step 1003, if not, executing step 1004;

[0081] 1003. Wait for the process to end;

[0082] 1004. The carrying device 300 is lowered to a low position and rotated;

[0083] 1005. The front protection nitrogen of the carrier device 300 is turned on;

[0084] 1006. Spraying a water mist cleaning medium into the gap 220 to clean the gap 220;

[0085] 1007. Close the first control valve 116 and the second control valve 117;

[0086] 1008. Spray nitrogen onto the surface of the carrier 300, and return the carrier 300 to its original position;

[0087] 1009. End.

[0088] The specific process is that before starting the self-cleaning process, first check whether there are wafers in the chamber for processing. If yes, wait until all wafer processes are completed before starting the cleaning process. If no, prepare to start the cleaning process.

[0089] Lower the carrier 300 to a low position so that the carrier 300 is within the range surrounded by the protective cover 200, start the carrier 300 to rotate, and then spray a protective gas, such as nitrogen, onto the surface of the carrier 300 to prevent residual process liquid, ultrapure water, etc. from entering the carrier 300;

[0090] After the above preparations are completed, the cleaning process is started, and a water mist cleaning medium is sprayed into the gap 220 through the spray assembly 120 to clean the pollutants accumulated in the gap 220 through the water mist cleaning medium.

[0091] Specifically, liquid cleaning medium and gas will enter the water mist generator 114 according to a preset flow ratio, and water mist cleaning medium will be generated by the water mist generator 114. The water mist cleaning medium will be sprayed into the spray cavity 121 through the nozzle 115, and will be blocked by the inner ring wall 1213 of the spray cavity 121 and diffuse in the spray cavity 121; after the water mist cleaning medium fills the spray cavity 121, it will diffuse downward through the grid holes 123 to clean the gap 220. While cleaning the gap 220, the water mist cleaning medium will gather downward along the wall of the gap 220, and finally all flow into the drain box 131, and pass through the gas-liquid separator 133. The generated waste gas will enter the factory through the waste gas branch pipe 134, and the generated waste liquid will enter the factory through the waste liquid branch pipe 135.

[0092] After the cleaning process lasts for a period of time (e.g., 1 minute), the first control valve 116 and the second control valve 117 are closed, the input of liquid cleaning medium and gas is stopped, and the cleaning medium is left to stand for a period of time (e.g., 1 minute) to ensure that all the water mist cleaning medium enters the drain box 131;

[0093] Nitrogen is sprayed onto the surface of the carrier 300 to dry the surface of the carrier 300. After the carrier 300 is dried, it can be returned to its original position to prepare for the next process.

[0094] In summary, the embodiment of the present application designs a spray cavity 121 for the gap 220 of the protective cover 200, and designs a grid hole 123, so that top-down spraying can be achieved, making the structure more concise, more stable, and having lower requirements on the flow rate of the cleaning medium and the spraying angle; and, using a water mist cleaning medium to clean the gap 220 can improve the uniformity of the cleaning effect to a certain extent.

[0095] Based on the above steps, by adjusting the flow ratio between the cleaning medium and the gas, the liquid content in the cleaning medium will not be too high or too low, ensuring that the cleaning medium and the gas have appropriate contents, thereby generating a water mist cleaning medium with a better cleaning effect to improve the cleaning effect. Therefore, the problems of not being able to clean the pollutants in the gap 220, uneven spray cleaning effect, and relatively poor stability can be alleviated.

[0096] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A semiconductor wet cleaning device, characterized in that: include: A cavity, a carrying device (300), a protective cover (200) and a self-cleaning device (100); The carrying device (300) and the protective cover (200) are both arranged in the cavity, the protective cover (200) is arranged around the outside of the carrying device (300), and the protective cover (200) comprises a multi-layer recovery chamber (210) arranged along the axial direction of the cavity and used for recovering process liquid, and a gap (220) is provided between two adjacent recovery chambers (210); The self-cleaning device (100) comprises a liquid inlet component (110) and a spray component (120); the spray component (120) is arranged in the gap (220); the liquid inlet component (110) is connected to the spray component (120) and is used to transport a cleaning medium to the spray component (120), and spray the cleaning medium to the gap (220) through the spray component (120).

2. The semiconductor wet cleaning equipment according to claim 1, characterized in that: The spray assembly (120) comprises a spray cavity (121), the spray cavity (121) is provided with an inlet (122), and the liquid inlet assembly (110) is in communication with the inlet (122); The spray cavity (121) is provided with a mesh hole (123), and the inner cavity of the spray cavity (121) and the gap (220) are connected through the mesh hole (123).

3. The semiconductor wet cleaning equipment according to claim 2, characterized in that: The spray cavity (121) is an annular cavity, and in the axial direction of the cavity, the cross-sectional area of ​​the first end opening of the spray cavity (121) is smaller than the cross-sectional area of ​​the second end opening.

4. The semiconductor wet cleaning equipment according to claim 3, characterized in that: The spray cavity (121) comprises an inclined top wall (1211), an inner annular wall (1213), an inclined bottom wall (1212) and an outer annular wall (1214) which are connected in sequence; The inclined top wall (1211) is connected to the top of the gap (220), the inclined bottom wall (1212) is spaced apart from the bottom of the gap (220), the grid holes (123) are distributed on the inclined bottom wall (1212), the inlet (122) is opened in a region of the inclined top wall (1211) close to the inner annular wall (1213), and the inlet (122) is arranged opposite to the inner annular wall (1213).

5. The semiconductor wet cleaning equipment according to claim 1, characterized in that: The liquid inlet assembly (110) comprises a liquid inlet branch pipe (111), an air inlet branch pipe (112), a liquid inlet main pipe (113), a water mist generator (114) and a nozzle (115); The liquid inlet branch pipe (111) and the air inlet branch pipe (112) are respectively connected to the input end of the water mist generator (114); the liquid inlet main pipe (113) is connected to the output end of the water mist generator (114); the nozzle (115) is connected to one end of the liquid inlet main pipe (113) away from the water mist generator (114), and is connected to the spray assembly (120).

6. The semiconductor wet cleaning equipment according to claim 5, characterized in that: The liquid inlet assembly (110) further comprises a first control valve (116), a second control valve (117), a first flow detection element (118) and a second flow detection element (119); The first control valve (116) and the first flow detection element (118) are both arranged on the liquid inlet branch pipe (111), and the first control valve (116) is electrically connected to the first flow detection element (118); The second control valve (117) and the second flow detection element (119) are both arranged on the intake branch pipe (112), and the second control valve (117) is electrically connected to the second flow detection element (119).

7. The semiconductor wet cleaning equipment according to claim 5, characterized in that: The spray assembly (120) comprises an annular spray cavity (121), the spray cavity (121) being provided with a plurality of inlets (122), the plurality of inlets (122) being evenly arranged along the circumference of the spray cavity (121); The liquid inlet assembly (110) comprises a plurality of nozzles (115), and the plurality of nozzles (115) are connected to the plurality of inlets (122) in a one-to-one correspondence.

8. The semiconductor wet cleaning equipment according to claim 1, characterized in that: The self-cleaning device (100) further comprises a liquid drainage assembly (130), wherein the liquid drainage assembly (130) comprises a liquid drainage box (131), a liquid drainage main pipe (132), a gas-liquid separator (133), a waste gas branch pipe (134) and a waste liquid branch pipe (135); The drain box (131) is located below the protective cover (200) and is used to receive the cleaning medium flowing out through the gap (220). The drain main pipe (132) is connected between the drain box (131) and the input end of the gas-liquid separator (133). The waste gas branch pipe (134) and the waste liquid branch pipe (135) are respectively connected to the output end of the gas-liquid separator (133).

9. A self-cleaning method for semiconductor wet cleaning equipment, applied to the semiconductor wet cleaning equipment according to any one of claims 1 to 8, characterized in that: The self-cleaning method comprises: The spray assembly (120) disposed in the gap (220) is used to spray a cleaning medium toward the gap (220), so that pollutants accumulated in the gap (220) are cleaned by the cleaning medium.

10. The self-cleaning method according to claim 9, characterized in that: The liquid inlet assembly (110) comprises a water mist generator (114); The self-cleaning method comprises: The pollutants accumulated in the gap (220) are cleaned by using a water mist cleaning medium generated by the water mist generator (114) and sprayed into the gap (220) via the spray assembly (120).

11. The self-cleaning method according to claim 10, characterized in that: The water mist generator (114) generates the water mist cleaning medium, comprising: Cleaning medium and gas are introduced into the water mist generator (114) respectively according to a preset flow ratio, so as to generate the water mist cleaning medium through the water mist generator (114).

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