Wafer cleaning equipment and wafer cleaning method

Abstract

The present application discloses a wafer cleaning device and a wafer cleaning method, wherein the wafer cleaning device comprises a carrier, the carrier is used to carry a wafer and carry the wafer to rotate; a spraying assembly, the spraying assembly is connected to a cleaning medium source, and the spraying assembly is located above the carrier, the spraying assembly is used to rotate synchronously with the carrier and spray the cleaning medium onto the wafer carried on the carrier; a temperature control assembly, the temperature control assembly is installed on the carrying surface of the carrier, and the temperature control assembly is located between the carrier and the wafer carried on the carrier, and is used to adjust the temperature of the wafer. The above technical solution can solve the problem that the back of the wafer is contaminated due to the need to spray hot deionized water on the back of the wafer to dry the wafer.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor processing technology, and specifically relates to a wafer cleaning device and a wafer cleaning method. Background Art

[0002] During wafer processing, it is usually necessary to clean the wafer to remove impurities on the front of the wafer. Deionized water is usually used during wafer cleaning. In order to ensure that the wafer is in a relatively dry state after cleaning and the temperature does not drop significantly, it is usually necessary to spray hot deionized water on the back of the wafer to heat the wafer on the back to increase the dryness of the front of the wafer. However, when using this drying method, the deionized water on the back of the wafer cannot be removed completely and contaminates the wafer. Summary of the invention

[0003] The present application discloses a wafer cleaning device and a wafer cleaning method, which can solve the problem that the back side of the wafer is contaminated due to the need to spray hot deionized water on the back side of the wafer to dry the wafer.

[0004] In order to solve the above problems, the embodiments of the present application are implemented as follows:

[0005] In a first aspect, an embodiment of the present application provides a wafer cleaning device, comprising:

[0006] A carrier, the carrier is used to carry the wafer and carry the wafer to rotate;

[0007] A spray assembly, the spray assembly is connected to a cleaning medium source and is located above the carrier, the spray assembly is used to rotate synchronously with the carrier and spray the cleaning medium onto the wafer carried on the carrier;

[0008] A temperature control component is installed on the carrying surface of the carrier, and the temperature control component is located between the carrier and the wafer carried on the carrier, and is used to adjust the temperature of the wafer.

[0009] In a second aspect, an embodiment of the present application provides a wafer cleaning method, which is applied to a wafer cleaning device. The wafer cleaning method includes:

[0010] Transferring the wafer to the carrier, and controlling the carrier to rotate while carrying the wafer;

[0011] Controlling the spraying assembly to rotate synchronously with the carrier and spraying a cleaning liquid onto the wafer;

[0012] Controlling the spraying component to stop spraying the cleaning liquid onto the wafer, and then spraying the replacement liquid onto the wafer, and controlling the temperature control component to adjust the temperature of the wafer to remain within a first preset temperature range;

[0013] The spraying component is controlled to stop spraying the replacement liquid onto the wafer, and then a dry gas is sprayed onto the wafer, and the temperature control component is controlled to adjust the temperature of the wafer to remain within a second preset temperature range.

[0014] An embodiment of the present application discloses a wafer cleaning device, which includes a carrier, a spraying component and a temperature control component, wherein the spraying component is capable of spraying a cleaning medium onto a wafer carried on the carrier to clean or purge one side of the wafer; and the temperature control component is located between the carrier and the wafer carried on the carrier to adjust the temperature of the wafer, so that the liquid cleaning medium sprayed on one side of the wafer can evaporate (or volatilize) under the action of the temperature control component, so as to prevent the back side of the wafer from being contaminated while allowing the front side of the wafer to have a better drying effect, thereby obtaining a clean and dry wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 It is a structural schematic diagram of a wafer cleaning device disclosed in an embodiment of the present application;

[0017] Figure 2 It is a structural schematic diagram of a spray head in a wafer cleaning device disclosed in an embodiment of the present application;

[0018] Figure 3 It is a structural schematic diagram of the main body of the wafer cleaning device disclosed in the embodiment of the present application;

[0019] Figure 4 is a flow chart of a wafer cleaning method disclosed in an embodiment of the present application;

[0020] Figure 5 A schematic diagram showing the correspondence between the temperature in the temperature zone and the heater power in the wafer cleaning method disclosed in the embodiment of the present application;

[0021] Figure 6 A schematic diagram of a specific process of the wafer cleaning method disclosed in an embodiment of the present application.

[0022] Description of reference numerals:

[0023] 110-base, 120-thimble,

[0024] 201-nozzle, 202-branch pipe, 203-heating part, 204-temperature detector, 205-return pipeline, 206-storage part, 207-filter part, 208-flow detector, 209-main pipe, 210-spraying head, 211-central area, 212-annular area, 220-rotation drive, 230-lifting drive,

[0025] 300-temperature control component, 310-heating zone,

[0026] 400-Cleaning medium source,

[0027] 500-wafer. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only 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 making creative work are within the scope of protection of the present application.

[0029] The technical solutions disclosed in various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0030] like Figure 1-Figure 3 As shown, the embodiment of the present application discloses a wafer cleaning device, which includes a carrier, a spray assembly and a temperature control assembly 300. Of course, the wafer cleaning device can also include other structures such as a process chamber, and the carrier, the spray assembly and the temperature control assembly 300 are all arranged in the process chamber.

[0031] The carrier is a device for carrying the wafer 500. During the processing of the wafer 500, the wafer 500 can be carried on the carrier. In addition, the carrier can also carry the wafer 500 to rotate, so as to ensure that the cleaning uniformity and comprehensiveness of the wafer 500 are relatively high during the cleaning process of the wafer 500. Optionally, the carrier is a chuck, which can carry the wafer 500 through the ejector pin 120. In this embodiment, as shown in FIG. Figure 1 As shown, the carrier includes a base 110 and a pin 120. The base 110 can be installed at the bottom of the process chamber. A rotational connection relationship can be formed between the base 110 and the process chamber, so that the carrier can provide a bearing function for the wafer 500 and drive the carried wafer 500 to rotate. The number of the pins 120 is at least three to ensure that the pins 120 can provide a stable bearing function for the wafer 500. In the process of carrying the wafer 500, the pins 120 can pass through the upper surface of the base 110, and the wafer 500 introduced into the process chamber can be carried on multiple pins 120.

[0032] The spray assembly is a device for spraying the cleaning medium in the wafer cleaning equipment. The spray assembly may be provided with a spray hole, or the spray assembly may include a nozzle, etc., which can ensure that the spray assembly has the ability to spray the cleaning medium, so as to provide a cleaning effect for the wafer 500 with the help of the cleaning medium, so as to achieve the purpose of cleaning the impurities on the front side of the wafer 500. During the operation of the wafer cleaning equipment, the spray assembly is connected to the cleaning medium source 400, and the cleaning medium source 400 is a device for storing the cleaning medium, or the cleaning medium source 400 can also be a pipeline for conveying the cleaning medium, etc. The cleaning medium includes at least one of a chemical liquid, deionized water, isopropyl alcohol and nitrogen.

[0033] At the same time, the spray assembly is located above the carrier, and the spray assembly can rotate synchronously with the carrier, and spray the cleaning medium onto the wafer 500 carried on the carrier. Specifically, the spray assembly can be rotatably mounted above the carrier, so that when the wafer 500 is carried on the carrier and the wafer 500 needs to be sprayed, the spray assembly can spray the cleaning medium onto the wafer 500 carried on the carrier; and by configuring a rotation drive mechanism for the spray assembly, it can be ensured that the spray assembly can rotate synchronously with the carrier to avoid convection between the spray assembly and the wafer 500, which affects the process results.

[0034] The temperature control component 300 is installed on the bearing surface of the carrier, which is the side of the carrier used to bear the wafer 500. Specifically, the temperature control component 300 can be installed on the carrier by bonding or connecting with a connector, and it can be located on the side surface of the carrier facing the wafer 500, or a gap can be provided between the temperature control component 300 and the carrier, which is not limited in this article. In the case of adopting the above-mentioned technical solution, when the carrier carries the wafer 500, the temperature control component 300 is located between the carrier and the wafer 500 carried on the carrier, and is used to adjust the temperature of the wafer 500.

[0035] Optionally, the temperature control component 300 includes an electric heating device, which can generate heat when powered on, so as to provide heat to the wafer 500, thereby ensuring that the cleaning medium on the front of the wafer 500 can evaporate (or volatilize), and does not cause a significant drop in the temperature of the wafer 500. When the temperature control component 300 is located between the carrier and the wafer 500 carried on the carrier, it is ensured that the temperature control component 300 can provide heat to the wafer 500 through the back of the wafer 500, and does not hinder the working process of the spray component.

[0036] An embodiment of the present application discloses a wafer cleaning device, which includes a carrier, a spraying component and a temperature control component 300, wherein the spraying component is capable of spraying a cleaning medium onto a wafer 500 carried on the carrier to clean or purge one side of the wafer 500; and the temperature control component 300 is located between the carrier and the wafer 500 carried on the carrier to adjust the temperature of the wafer 500, so that the liquid cleaning medium sprayed on one side of the wafer 500 can evaporate (or volatilize) under the action of the temperature control component 300, so as to prevent the back side of the wafer 500 from being contaminated while making the front side of the wafer 500 have a better drying effect, thereby obtaining a clean and dry wafer 500.

[0037] During the cleaning process of the wafer 500, different areas on the wafer 500 may need different amounts of cleaning medium to be sprayed. Based on the above reasons, the spray assembly further includes a medium pipe, a spray head 210, a rotary driver 220, a nozzle 201, and a first control device. The spray head 210 is the main structure of the spray assembly, and the shape of the spray head 210 can be determined according to actual needs. Considering that the shape of the wafer 500 is usually circular, the spray head 210 can also be a circular structural member to make the spray head 210 correspond better to the wafer 500.

[0038] The spray head 210 is arranged above the carrier so that the cleaning medium sprayed by the spray head 210 can be sprayed on the wafer 500 carried on the carrier. The rotary driver 220 is arranged on the side of the spray head 210 away from the carrier so that the spray head 210 can be driven to rotate by the rotary driver 220 so that the spray head 210 can rotate synchronously with the carrier. The rotary driver 220 can be specifically a rotary motor. By installing the spray head 210 on the driving shaft of the rotary motor, the spray head 210 can be driven to rotate by the rotary motor. One end of the medium pipe is installed on the side of the spray head 210 away from the carrier and is connected to the spray head 210. The other end of the medium pipe is connected to the cleaning medium source, so that the cleaning medium in the cleaning medium source is transported to the spray head 210 by the medium pipe.

[0039] In addition, the spray head 210 is provided with a plurality of spraying areas on one side facing the carrier, and the projections of the plurality of spraying areas in the carrying direction of the carrier cover the wafer 500 carried on the carrier, that is, the plurality of spraying areas correspond to the wafer 500 carried on the carrier, and the cleaning medium sprayed from the plurality of spraying areas can cover the wafer 500 carried on the carrier. The specific shape of the carrying area can be determined according to actual conditions, and the shape and area of ​​each carrying area can be the same or different, which is not limited here.

[0040] Each spraying area is provided with a nozzle 201 to ensure that each spraying area has the ability to spray the cleaning medium to the corresponding area on the wafer 500. The nozzle 201 can be installed in the center of the spraying area, or the nozzles 201 in each spraying area are arranged in correspondence with each other to ensure that the cleaning medium sprayed by multiple nozzles 201 can cover the surface of the wafer 500 carried on the carrier.

[0041] In addition, each spraying area is equipped with an independent first control device, and each first control device is connected to the nozzle 201 in the corresponding spraying area to control the opening and closing of the nozzle 201. In detail, each spraying area is equipped with a first control device, and multiple spraying areas are equipped with multiple first control devices, and the multiple first control devices are independent of each other, ensuring that any one of the multiple first control devices can be controlled individually, so as to control the operation of the nozzle 201 in the corresponding spraying area. The first control device corresponding to each spraying area is connected to all the nozzles 201 in the corresponding spraying area, ensuring that the nozzles 201 in the spraying area can all work under the action of the first control device.

[0042] The first control device may be a valve, and optionally, the first control device may also be a solenoid valve, so as to remotely control the nozzle 201 in the spraying area. Of course, multiple first control devices may also be connected to a control center, so that the control center can uniformly control multiple first control devices, thereby controlling multiple spraying areas in the spraying assembly to work according to set rules, and the set rules include parameters such as spraying sequence and spraying amount.

[0043] In this embodiment, the specific working conditions of multiple spraying areas can be controlled with the help of multiple first control devices, so that different areas on the wafer 500 can be selectively cleaned according to the specific conditions of the wafer 500 carried on the carrier, so as to reduce the workload while obtaining better cleaning effects, and also reduce the waste of cleaning media and energy.

[0044] Based on the above embodiment, optionally, at least one spraying area is provided with a plurality of nozzles 201, and the plurality of nozzles 201 are evenly and spacedly arranged in the spraying area. Under the joint action of the plurality of evenly arranged nozzles 201, the spraying uniformity of the cleaning medium in the spraying area can be further improved, ensuring that the area corresponding to the spraying area on the wafer 500 can be evenly and comprehensively covered with the cleaning medium. Specifically, the arrangement of the nozzles 201 can be determined according to the specific shape of the spraying area, which is not limited here.

[0045] Optionally, the spray assembly disclosed in the embodiment of the present application further includes a lifting driver 230, which is arranged on the side of the spray head 210 away from the carrier, and is used to drive the spray head 210 to rise and fall. That is, in this embodiment, by providing the lifting driver 230 for the spray head 210, the spacing between the spray head 210 and the wafer 500 carried on the carrier can be controlled, and then the spacing between the spray head 210 and the wafer 500 carried on the carrier can be selectively controlled according to the specific situation of the wafer 500 carried on the carrier. Specifically, the lifting driver 230 can be a lifting cylinder or a linear motor, etc., and the spray head 210 can be installed at the driving end of the lifting driver 230, so that the spray head 210 can be driven by the lifting driver 230 to produce a lifting action. Of course, in the case where the wafer cleaning equipment includes a rotary driver, the rotary driver can be installed on the lifting driver 230, and the spray head can be installed on the rotary driver.

[0046] In the case where a plurality of spraying areas are provided on the spray head 210 of the spray assembly, optionally, as Figure 2 As shown, the multiple spraying areas include a central area 211 and at least one annular area 212, and the annular areas 212 are arranged in sequence, and the central area 211 is arranged at the center of each annular area 212. Among them, the shape of the annular area 212 can be a square ring or a polygonal ring, etc. In order to better adapt to the shape of the wafer 500, the central area 211 can be a circular structure, and the annular areas 212 are all circular ring structures. When the above technical solution is adopted, the difficulty of controlling the spraying sequence of multiple spraying areas can be reduced, and the mutual interference between the spraying areas can be minimized. Specifically, in the process of cleaning the wafer 500, the multiple spraying areas can be controlled to spray in an order from the inside to the outside or from the outside to the inside.

[0047] In addition, when the plurality of spraying areas include a central area 211 and at least one annular area 212, a plurality of nozzles 201 may be disposed in each annular area 212, and the plurality of nozzles 201 are disposed evenly and at intervals. Specifically, the plurality of nozzles 201 in each annular area 212 are evenly distributed along the circumferential direction.

[0048] As described above, the spray head 210 of the spray assembly can be provided with a plurality of spray areas, and the plurality of spray areas can be independently controlled so that any spray area can spray the cleaning medium under controlled conditions. In this case, since some areas on the wafer 500 are sprayed with the cleaning medium, but other areas on the wafer 500 are not sprayed with the cleaning medium, the evaporation (or volatilization) of the cleaning medium will absorb heat, and the heat of the area not sprayed with the cleaning medium will hardly decrease.

[0049] Based on this, in order to prevent the situation that particles appear due to different drying conditions between different areas of the wafer 500 due to the fact that some areas of the wafer 500 are also in a heated state when not sprayed with the cleaning medium, thereby affecting the quality of the wafer 500 and even causing the wafer 500 to be scrapped, optionally, in this embodiment, the temperature control component 300 includes a second control device and an electric heating device, wherein, as Figure 3 As shown, the carrying surface is provided with a plurality of heating zones 310 , and the projections of the plurality of heating zones 310 in the carrying direction of the carrying member cover the wafer 500 carried on the carrying member, thereby ensuring that the plurality of heating zones 310 can provide heating for any area on the entire wafer 500 .

[0050] At the same time, multiple heating zones 310 are arranged in one-to-one correspondence with multiple spraying zones, and the projection of any heating zone 310 and the corresponding spraying zone in the carrying direction of the carrier coincides, that is, the one-to-one corresponding heating zones 310 and spraying zones have the same shape and size, and their positions on both sides of the wafer 500 are the same.

[0051] Furthermore, each heating zone 310 is provided with the above-mentioned electric heating device, and each heating zone is equipped with an independent second control device to ensure that each heating zone 310 can provide independent heating and provide heat for the corresponding area on the wafer 500. In order to ensure that each heating zone 310 can work independently, each second control device is connected to the electric heating device in the corresponding heating zone 310, so that the working conditions of the multiple heating zones 310, including working status and heating parameters, are controlled respectively through the multiple second control devices.

[0052] Specifically, the electric heating device can be a resistance wire or an infrared heating element, etc., and the second control device can be a switch or an electromagnetic switch, etc. By controlling the on-off state of the second control device, the working state of the electric heating device in the heating area 310 connected to the second control device can be controlled. Of course, the second control device can also include a variable resistor, etc., so as to control the heating current of the electric heating device connected to the second control device through the second control device, so as to achieve the purpose of controlling the heating temperature of the heating area 310.

[0053] In the above embodiment, when the wafer 500 carried on the carrier needs to be cleaned, the spray heads 210 in the multiple spraying areas can be controlled by multiple first control devices according to preset rules to spray the cleaning medium in sequence; at the same time, when the spray heads 210 in the multiple spraying areas are started and closed, the opening and closing of the electric heating devices in the corresponding heating areas 310 can be controlled by multiple second control devices accordingly.

[0054] Specifically, taking the example that both the spraying area and the heating area 310 include four, the four spraying areas are the first spraying area, the second spraying area, the third spraying area and the fourth spraying area, respectively, and correspondingly, the four heating areas 310 are the first heating area, the second heating area, the third heating area and the fourth heating area, respectively, corresponding to the four spraying areas one by one. In the specific cleaning process, the first spraying area and the first heating area are turned on and off at the same time, the second spraying area and the second heating area are turned on and off at the same time, and so on, so that the spraying area and the heating area 310 corresponding to the same area on the wafer 500 work together, ensuring that the area on the wafer 500 sprayed with the cleaning medium can be in a heated state, providing heat for the evaporation (or volatilization) of the cleaning medium, and ensuring that the temperature at each position on the wafer 500 is relatively stable, and the cleaning medium will not absorb the heat of the wafer 500, resulting in different temperatures at different positions on the wafer 500, which will have an adverse effect on the quality of the wafer 500.

[0055] In addition, the temperature control component 300 may also include a temperature limiting device. The electric heating devices in each heating zone 310 are all equipped with a temperature limiting device. The temperature limiting device can limit the operation of the electric heating device when the temperature of the area of ​​the wafer 500 corresponding to the heating zone 310 exceeds the preset temperature range. That is, the temperature limiting device provides a temperature fuse in the temperature control component 300. When the heating work of the heating zone 310 is uncontrolled due to some unexpected factors, the temperature limiting device can prevent the heating zone 310 from heating the area on the wafer 500 corresponding to the heating zone 310 to a temperature exceeding the preset range, thereby preventing the wafer 500 from being damaged due to excessive temperature.

[0056] Optionally, the temperature control component 300 can control the parameters such as the heating power of the heating zone 310 by means of feedback regulation. Specifically, by detecting the temperature of the area corresponding to the heating zone 310 on the wafer 500, the real-time temperature of the area can be obtained. By comparing the real-time temperature with the target temperature, based on the preset algorithm, the parameters such as the heating power of the electric heating device of the heating zone 310 can be obtained; and, during the heating process, the heating power of the electric heating device of the heating zone 310 can be adjusted accordingly by means of real-time detection and corresponding regulation, so as to provide the cleaning medium with heat that meets the requirements while ensuring that the temperature of the wafer 500 does not change significantly before and after cleaning. At the same time, in the case where the types of cleaning media sprayed by the spray component are different, the heating power of the corresponding heating zone 310 can be flexibly determined according to the specific type of the cleaning medium and the specific spraying amount.

[0057] Optionally, in this embodiment, the spray assembly includes a main pipe 209 and a plurality of branch pipes 202, one end of the main pipe 209 is connected to the spray head 210, and the other end is connected to a plurality of different cleaning medium sources through a plurality of branch pipes 202, and at least one branch pipe is provided with at least one of a heating unit 203, a filtering unit 207, a storage unit 206, a temperature detector 204, and a flow detector 208. The heating unit 203 can heat the cleaning medium, the filtering unit 207 can filter impurities in the cleaning medium, the storage unit 206 can store the cleaning medium, the temperature detector 204 can detect the temperature of the cleaning medium, and the flow detector 208 can detect the flow of the cleaning medium. In the wafer cleaning device disclosed in this embodiment, the cleaning effect of the cleaning medium can be improved by adjusting the temperature and cleanliness of the cleaning medium. In addition, the flow rate of the cleaning medium can be obtained with the help of the flow detector 208, so as to achieve the purpose of quantitatively controlling the flow rate of the cleaning medium. Specifically, the heating part 203 can be a device that can provide heating capability, such as a resistance wire. By installing the heating part 203 outside the branch pipe 202, the heating part 203 can provide heating for the cleaning medium while preventing contamination of the cleaning medium.

[0058] Optionally, the cleaning medium source includes a cleaning liquid source, a replacement liquid source, and a dry gas source. More specifically, the cleaning liquid source may include a chemical liquid, the replacement liquid source may include deionized water and isopropanol, and the dry gas source may include nitrogen.

[0059] As described above, at least one branch pipe is provided with a heating unit 203 and a temperature detector 204. In this case, in order to ensure that the temperature of the cleaning medium delivered to the nozzle 201 can be heated to a temperature that meets the requirements and the cleaning medium will not be heated to a boiling state, the temperature detector 204 is optionally provided downstream of the heating unit 203, so that the temperature of the cleaning medium in the branch pipe 202 that has been heated by the heating unit 203 can be detected by the temperature detector 204. Of course, the spray assembly may also include or be equipped with a control mechanism to control the heating power and heating time of the heating unit 203 through the control mechanism.

[0060] A return pipe 205 is also provided on the branch pipe, one end of the return pipe 205 is connected to the portion of the branch pipe 202 located between the temperature detector 204 and the main pipe 209, and the other end of the return pipe 205 is connected to the portion of the branch pipe 202 located between the heating part 203 and the cleaning medium source 400, that is, when the return pipe 205 is in an open state, the cleaning medium in the branch pipe 202 heated by the heating part 203 can flow back to the upstream of the heating part 203 in the branch pipe 202 through the return pipe 205. During the operation of the spray assembly, the preset temperature can be determined according to the type of cleaning medium and other conditions. The temperature of the cleaning medium heated by the heating part 203 can be detected by the temperature detector 204. When the detection result of the temperature detector 204 does not meet the preset temperature range, the return line 205 is opened to allow the cleaning medium whose temperature does not meet the preset temperature range to flow back to the upstream of the heating part 203. According to its specific temperature conditions, the cleaning medium with a lower temperature is reheated or added to ensure that the temperature of the cleaning medium transported from the branch pipe 202 to the spray head meets the preset temperature range, thereby improving the cleaning and drying effects of the wafer 500.

[0061] As described above, in the case where the cleaning medium source 400 is a source pipeline, the spray assembly may further include a storage unit 206, which is capable of accommodating the cleaning medium. In the case where the storage unit 206 is provided, one end of the return pipeline 205 may be directly connected to the storage unit 206 to re-transport the cleaning medium whose temperature does not meet the preset temperature range back to the upstream of the heating unit 203. As described above, the spray assembly may further include a filter unit 207, which is connected to the branch pipe 202, and the filter unit 207 may be located downstream of the temperature detector 204 and the return pipeline 205, so as to filter the cleaning medium to be transported to the spray head 210, improve the cleanliness of the cleaning medium, and thereby improve the cleaning and drying effects on the wafer 500.

[0062] Based on the wafer cleaning device disclosed in any of the above embodiments, the present application also discloses a wafer cleaning method, which is applied to any of the above wafer cleaning devices. Figure 4 As shown, the wafer cleaning method includes:

[0063] S1. Transfer the wafer to the carrier, and control the carrier to carry the wafer to rotate. Specifically, the wafer to be cleaned can be transferred into the process chamber by a robot or other device, and the wafer can be supported on the carrier, and the carrier drives the wafer to rotate through its own structure. Of course, the wafer can also be moved with the help of other devices, which will not be listed here one by one.

[0064] S2, control the spray assembly to rotate synchronously with the carrier, and spray the cleaning liquid onto the wafer. Specifically, when the wafer is carried on the carrier, control the spray assembly to rotate synchronously with the carrier, so that the spray assembly can spray the cleaning liquid onto any position on the wafer to provide a cleaning effect for the wafer.

[0065] S3, controlling the spraying assembly to stop spraying the cleaning liquid onto the wafer, and then spraying the replacement liquid onto the wafer, and controlling the temperature control assembly to adjust the temperature of the wafer to remain within a first preset temperature range. Specifically, by switching the cleaning medium delivered to the spraying assembly, the spraying assembly stops spraying the cleaning liquid onto the wafer, and by introducing the replacement liquid into the spraying assembly, the spraying assembly is able to spray the replacement liquid onto the wafer.

[0066] In order to ensure a better cleaning effect, during the spraying of the replacement fluid, the temperature of the wafer is also adjusted to remain within the first preset range by controlling the temperature control component. Specifically, by making the temperature control component work, the wafer can be heated from the other side of the wafer to provide heat for the evaporation (or volatilization) of the replacement fluid, thereby preventing the temperature of the wafer from changing significantly before and after spraying the cleaning medium. Among them, the cleaning fluid can specifically include a chemical solution, and the replacement fluid can include deionized water and isopropyl alcohol. In addition, the first preset temperature can be flexibly determined according to actual needs such as the specific type of replacement fluid, and is not limited here.

[0067] S4, controlling the spraying component to stop spraying the replacement liquid onto the wafer, and then spraying the drying gas onto the wafer, and controlling the temperature control component to adjust the temperature of the wafer to remain within a second preset temperature range.

[0068] After the wafer is cleaned with the replacement fluid for a period of time, the replacement fluid can be stopped from being sprayed on the wafer, and the drying gas can be sprayed on the wafer by switching the cleaning medium source of the spray head. In addition, while spraying the drying gas, the temperature control component is also controlled to adjust the temperature of the wafer, and the temperature of the wafer is kept within the second preset temperature range to improve the drying effect of the wafer. The drying gas can specifically be nitrogen to prevent the drying gas from reacting with the wafer. In addition, the second preset temperature can be flexibly determined according to actual conditions such as the spraying speed of the nitrogen, and is not limited here.

[0069] In the process of cleaning the wafer using the above wafer cleaning method, the front side of the wafer can be dried better while preventing the back side of the wafer from being contaminated, thereby obtaining a clean and dry wafer.

[0070] As described above, the spray assembly may include a spray head, the spray head is provided with multiple spray areas, each spray area is provided with a nozzle, the temperature control assembly includes multiple heating areas corresponding to the multiple spray areas, each heating area is provided with a corresponding control device. Considering that the above embodiment has already described the wafer cleaning equipment of the aforementioned structure in detail, it will not be repeated here to make the text concise.

[0071] Based on the above wafer cleaning equipment, in the above step S2 of the wafer cleaning method, controlling the spraying component to stop spraying the cleaning liquid to the wafer, and then spraying the replacement liquid to the wafer, includes:

[0072] The spray assembly is controlled to stop spraying cleaning liquid onto the wafer, and then multiple spray areas are controlled to open their nozzles in sequence to spray replacement liquid onto the wafer. In addition, multiple heating areas are controlled to turn on their electric heating devices in sequence according to the opening order of the multiple spray areas to adjust the temperature of the corresponding areas of the wafer.

[0073] As described above, in the wafer cleaning equipment, when the spraying component includes multiple spraying areas, and the temperature control component includes heating areas corresponding to the multiple spraying areas one by one, any spraying area and the heating area corresponding to the spraying area can be opened separately to clean part of the wafer. This makes the wafer cleaning process more flexible and can perform adaptive cleaning work according to the cleanliness level of different positions on the wafer.

[0074] More specifically, after completing the spraying of the cleaning liquid, the nozzles of multiple spraying areas can be controlled to open in sequence, and the replacement liquid can be sprayed onto the wafer. While the replacement liquid is sprayed in the corresponding spraying area, the multiple heating areas can be controlled in sequence according to the opening sequence of the multiple spraying areas by turning on their electric heating devices to adjust the temperature of the corresponding area of ​​the wafer, so that the cleaning effect of the area on the wafer corresponding to the opened spraying area is better.

[0075] Based on the wafer cleaning method disclosed in the above embodiment, a specific workflow of the wafer cleaning method is provided herein.

[0076] In the process of cleaning the wafer, when the wafer is introduced into the cleaning chamber and the wafer is carried on the carrier, after the impurities on the surface of the wafer are cleaned by using a chemical solution, Figure 6 As shown, the surface of the wafer can be cleaned with an aqueous cleaning solution such as UPW or CO2-UPW. At the same time, nitrogen gas can be sprayed on the back of the wafer to prevent the cleaning solution on the front of the wafer from flowing from the edge of the wafer to the back of the wafer and causing contamination of the back of the wafer.

[0077] After the surface of the wafer is cleaned with an aqueous cleaning solution, an organic solvent with a lower surface tension can be further used to clean the front of the wafer. The aforementioned organic solvent can be specifically liquid isopropyl alcohol (i.e., IPA). By maintaining the temperature of the isopropyl alcohol above 60°C and below its boiling point, the cleaning effect of the aqueous cleaning solution on the surface of the wafer by isopropyl alcohol is ensured to be better. While the front of the wafer is cleaned with an organic solvent, a closed-loop temperature control heating system such as the temperature control component described above can be used to heat the back of the wafer. When heating the back of the wafer, the power of the heating system on the back of the wafer can be adjusted according to the target process temperature and process changes of the front of the wafer, as well as the changes in the temperature of the front of the wafer, to ensure that the temperature of each area on the front of the wafer remains basically the same. When the back of the wafer is heated with the above-mentioned closed-loop temperature control heating system, on the one hand, the stability of the temperature of the front of the wafer during the isopropyl alcohol drying process can be well maintained, and on the other hand, the back contamination problem caused by incomplete drying of the back of the wafer can be effectively prevented.

[0078] When spraying isopropyl alcohol on the front of the wafer, an instantaneous full coverage nozzle design is used. The full coverage nozzle design divides the surface of the shower head facing the wafer into several independently opened or closed spraying areas according to process requirements, so that during the spraying of isopropyl alcohol, multiple spraying areas are independently controlled to ensure that isopropyl alcohol can basically fully cover any position on the wafer surface, preventing different areas of the wafer surface from having different concentrations of isopropyl alcohol at different positions on the wafer surface due to differences in the amount of isopropyl alcohol sprayed, causing particle problems, and can shorten the drying time.

[0079] In addition, according to the multiple spraying areas set by the spray head facing the front side of the wafer, the closed-loop temperature control heating system set on the back side of the wafer can be divided into several heating zones accordingly. Each heating zone adjusts the power of the closed-loop temperature control heating system on the back side of the wafer according to factors such as the target process temperature of the front side of the wafer, whether isopropyl alcohol is sprayed, and the temperature of the area on the wafer surface sprayed with isopropyl alcohol, so as to ensure that the temperature at different positions on the front side of the wafer remains basically consistent and ensure that the wafer has a better drying effect.

[0080] Specifically, Figure 5 As shown, when the first spraying area corresponding to the surface of the front side of the wafer in the spray head (referred to as the front side area 1, as shown in FIG. Figure 5 When the medium temperature zone A) starts to spray isopropyl alcohol, the heating area 1 on the back of the wafer corresponding to the front area 1 can start to be heated, and the heating power of the heating area 1 can be automatically adjusted to A according to the temperature feedback of the heating area 1; when the front area 1 stops spraying isopropyl alcohol, the corresponding heating area 1 can automatically adjust the heating power to A1 according to the process requirements at this time.

[0081] Similarly, the spraying of isopropyl alcohol is finished in the front area 1, and the second spraying area (referred to as the front area 2, such as Figure 5 When the middle temperature zone B) starts to spray isopropyl alcohol, the heating system on the back of the wafer and the heating zone 2 corresponding to the front zone 2 can automatically adjust the heating power of the heating zone 2 to B according to the temperature feedback of the heating zone 2; and when the front zone 2 stops spraying isopropyl alcohol, the heating zone 2 can automatically adjust the power of the heating zone 2 in the heating system to B1 according to the process requirements at that time. And so on, until the nth (n is a non-zero natural number) spraying zone on the front of the wafer completes the isopropyl alcohol spraying cleaning process, the corresponding heating zone n can also use the above method to complete the power adjustment work of the heating zone n accordingly.

[0082] After the front of the wafer is cleaned with isopropyl alcohol, the supply of isopropyl alcohol is stopped and nitrogen is introduced, or the nitrogen is heated before introduction to improve the drying effect of nitrogen on the wafer surface. At the same time, the closed-loop temperature control heating system on the back of the wafer can automatically adjust the heating power to a certain value according to the changes in the cleaning process of the front of the wafer, and evaporate all or almost all of the isopropyl alcohol remaining on the front of the wafer, so as to obtain a wafer with a clean and dry surface (including the front and back) for use in the next process.

[0083] In the process of spraying nitrogen onto the front side of the wafer, nitrogen can be sprayed onto the front side of the wafer in an instantaneous full coverage manner. That is, when spraying nitrogen, nitrogen is no longer sprayed in multiple spraying areas. By instantaneously covering the entire surface of the front side of the wafer with nitrogen, the problem of uneven drying of the front side of the wafer due to uneven nitrogen coverage can be effectively prevented, and at the same time, the drying time of the wafer can be greatly shortened.

[0084] The above embodiments of the present application focus on describing the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0085] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A wafer cleaning device, characterized in that: include: A carrier, the carrier is used to carry the wafer and carry the wafer to rotate; A spray assembly, the spray assembly comprising a medium pipe and a spray head, the spray head being located above the carrier, one end of the medium pipe being connected to the spray head on a side of the spray head away from the carrier, and the other end being connected to a cleaning medium source, the spray assembly being used to rotate synchronously with the carrier and spray a cleaning medium onto the wafer carried on the carrier, the medium pipe comprising a main pipe and a plurality of branch pipes, one end of the main pipe being connected to the spray head, and the other end being connected to a plurality of different cleaning medium sources through the plurality of branch pipes, at least one of the branch pipes being provided with a heating portion and a temperature detector, the temperature detector being located downstream of the heating portion, the branch pipe being further provided with a return line, one end of the return line being connected to a portion of the branch pipe located between the temperature detector and the main pipe, the other end of the return line being connected to a portion of the branch pipe located between the heating portion and the cleaning medium source, the return line being used to be conducted when a detection result of the temperature detector does not meet a preset temperature range; A temperature control component is installed on the bearing surface of the carrier, and the temperature control component is located between the carrier and the wafer carried on the carrier, and the temperature control component includes an electric heating device for adjusting the temperature of the wafer.

2. The wafer cleaning equipment according to claim 1, characterized in that: The spray assembly includes a rotary driver, a nozzle and a first control device. The rotary driver is arranged on a side of the spray head away from the carrier, and is used to drive the spray head to rotate. The spray head is provided with a plurality of spray areas on a side facing the carrier, and the projections of the plurality of spray areas in the carrying direction of the carrier cover the wafer carried on the carrier. The nozzle is provided in each spray area, and each spray area is equipped with an independent first control device. Each first control device is connected to the nozzle in the corresponding spray area, and is used to control the opening and closing of the nozzle.

3. The wafer cleaning equipment according to claim 2, characterized in that: The spray assembly further comprises a lifting drive, which is arranged on a side of the spray head away from the bearing member and is used for driving the spray head to rise and fall.

4. The wafer cleaning equipment according to claim 2, characterized in that: The plurality of spraying areas include a central area and at least one annular area, the annular areas are arranged in sequence around each other, and the central area is arranged at the center of each annular area.

5. The wafer cleaning equipment according to claim 2, characterized in that: The temperature control component includes a second control device, and the carrying surface is provided with a plurality of heating zones, and the projections of the plurality of heating zones in the carrying direction of the carrying member cover the wafer carried on the carrying member, and the plurality of heating zones are arranged in a one-to-one correspondence with the plurality of spraying zones, and any heating zone coincides with the projection of the corresponding spraying zone in the carrying direction of the carrying member, and each of the heating zones is provided with the electric heating device, and each of the heating zones is equipped with an independent second control device, and each of the second control devices is connected to the electric heating device in the corresponding heating zone for controlling the on and off of the electric heating device.

6. The wafer cleaning equipment according to claim 2, characterized in that: At least one of a heating unit, a filtering unit, a storage unit, a temperature detector and a flow detector is provided on at least one of the branch pipes. The heating unit is used to heat the cleaning medium. The filtering unit is used to filter impurities in the cleaning medium. The storage unit is used to store the cleaning medium. The temperature detector is used to detect the temperature of the cleaning medium. The flow detector is used to detect the flow rate of the cleaning medium.

7. The wafer cleaning equipment according to claim 6, characterized in that: The cleaning medium source includes: a cleaning liquid source, a replacement liquid source, and a drying gas source.

8. A wafer cleaning method, applied to the wafer cleaning device according to claim 5, characterized in that: include: Transferring the wafer to the carrier, and controlling the carrier to rotate while carrying the wafer; Controlling the spraying assembly to rotate synchronously with the carrier and spraying a cleaning liquid onto the wafer; Controlling the spraying component to stop spraying the cleaning liquid onto the wafer, and then spraying the replacement liquid onto the wafer, and controlling the temperature control component to adjust the temperature of the wafer to remain within a first preset temperature range; The spraying component is controlled to stop spraying the replacement liquid onto the wafer, and then a dry gas is sprayed onto the wafer, and the temperature control component is controlled to adjust the temperature of the wafer to remain within a second preset temperature range.

9. The wafer cleaning method according to claim 8, characterized in that: The controlling the spraying assembly to stop spraying the cleaning liquid onto the wafer and then spraying the replacement liquid onto the wafer comprises: The spray assembly is controlled to stop spraying the cleaning liquid onto the wafer, and then the plurality of spray areas are controlled to open their nozzles in sequence to spray the replacement liquid onto the wafer, and according to the opening sequence of the plurality of spray areas, the plurality of heating areas are controlled to turn on their electric heating devices in sequence to adjust the temperature of the corresponding area of ​​the wafer.

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