Cleaning machine table, chemical mechanical polishing system and control method of cleaning machine table

Abstract

A cleaning machine table, a chemical mechanical polishing system and a control method of the cleaning machine table, the cleaning machine table is suitable for cleaning a wafer after chemical mechanical polishing, the cleaning machine table comprises a cleaning chamber, the cleaning chamber is internally provided with a cleaning pool, and the cleaning pool is suitable for containing liquid to clean the wafer; the spraying head is arranged in the cleaning chamber, and the spraying head sprays liquid towards the cleaning pool so as to wash the surface of the cleaning pool. The spraying head sprays liquid to the cleaning pool so as to wash the surface of the cleaning pool, chemical liquid drops dripping on the surface of the cleaning pool on the surface of the wafer after chemical mechanical grinding can be removed, and the possibility that crystals are formed on the surface of the cleaning pool is reduced; the spraying range of the spraying head is large, the surface of the cleaning pool can be washed in a large range, the cleaning pool can be washed more comprehensively, crystals of chemical liquid drops formed on the surface of the cleaning pool are effectively reduced, and defects caused by the fact that crystal particles adhere to the surface of a wafer can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and particularly to a cleaning machine, a chemical mechanical polishing system, and a control method for the cleaning machine. Background Art

[0002] Chemical Mechanical Polishing (CMP) process is a step in semiconductor manufacturing. Chemical Mechanical Polishing combines chemical corrosion and mechanical removal. The chemical components in the polishing liquid first slightly react with the material to be removed on the wafer surface to soften it, and then the polishing head applies pressure and moves relative to the polishing pad to physically remove the reactants to achieve the leveling purpose.

[0003] In the process of semiconductor integrated circuit manufacturing, after the wafer is polished in a chemical mechanical polishing machine, the wafer needs to be transferred to a clean room for a series of cleaning steps. After cleaning the wafer, it is also necessary to dry the wafer to complete the chemical mechanical polishing process completely.

[0004] However, there are still many problems with the current cleaning machine. Summary of the Invention

[0005] The problem to be solved by the present invention is how to improve the cleaning machine to reduce the possibility of defects on the wafer surface and improve the product yield.

[0006] To solve the above problems, the technical solution of the present invention provides a cleaning machine, which is suitable for cleaning the wafer after chemical mechanical polishing. The cleaning machine includes: a cleaning chamber having a cleaning pool therein, and the cleaning pool is suitable for containing liquid to clean the wafer; a spray head disposed in the cleaning chamber, and the spray head sprays liquid towards the cleaning pool to wash the surface of the cleaning pool.

[0007] Optionally, the spray head includes a fan-shaped spray head.

[0008] Optionally, it further includes: a water delivery pipe suitable for connecting with the spray head to supply the liquid to the spray head.

[0009] Optionally, it further includes: a pneumatic valve suitable for pressurizing the liquid.

[0010] Optionally, the pneumatic valve includes a first end, a second end, and a third end. The first end is suitable for connecting with the water delivery pipe, the second end is suitable for connecting with the spray head, and the third end is suitable for connecting with a gas source.

[0011] Optionally, it further includes: a drain trough adapted to receive the liquid for flushing the cleaning tank.

[0012] Optionally, the spray head is disposed on one side of the cleaning tank; the drain trough is disposed on the other side of the cleaning tank.

[0013] Optionally, the surface of the cleaning tank on the side close to the spray head is higher than the surface of the cleaning tank on the side close to the drain trough.

[0014] Optionally, along the direction from the side close to the spray head to the side close to the drain trough, the surface of the cleaning tank gradually decreases.

[0015] Optionally, along the extending direction of the drain trough, the drain trough has an opposite end and another end, and the bottom surface of one end of the drain trough is higher than the bottom surface of the other end of the drain trough.

[0016] Optionally, along the extending direction of the drain trough, the bottom surface of the drain trough gradually decreases.

[0017] Optionally, the number of the spray heads is at least two, and the at least two spray heads are disposed on the same side of the cleaning tank.

[0018] Optionally, it further includes: a control module adapted to control the spray head to flush the cleaning tank.

[0019] Optionally, it further includes: an air extraction module adapted to extract the air in the cleaning chamber.

[0020] Optionally, the cleaning tank is an ultrasonic cleaning tank.

[0021] Correspondingly, the technical solution of the present invention further provides a chemical mechanical polishing system, including: a polishing machine platform adapted to perform chemical mechanical polishing on a wafer; a cleaning machine platform as described in any one of the above, the cleaning machine platform adapted to clean the wafer after chemical mechanical polishing; a transfer mechanism adapted to transfer the wafer from the polishing machine platform to the cleaning machine platform.

[0022] Correspondingly, the technical solution of the present invention further provides a control method for a cleaning machine platform, the cleaning machine platform being as described in any one of the above, the control method including: after the cleaning machine platform cleans a batch of wafers and before the cleaning machine platform cleans the next batch of wafers, causing the spray head to spray out liquid to flush the surface of the cleaning tank.

[0023] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0024] In the cleaning machine platform of the technical solution of the present invention, the spray head is arranged in the cleaning chamber, and the spray head sprays liquid towards the cleaning pool to wash the surface of the cleaning pool. There is a spray head arranged in the cleaning chamber of the cleaning machine platform. The spraying direction of the spray head faces the cleaning pool. The spray head can spray liquid towards the cleaning pool to wash the surface of the cleaning pool, which can remove the chemical droplets dropped on the surface of the cleaning pool from the surface of the wafer after chemical mechanical polishing, so as to reduce the possibility of crystallization on the surface of the cleaning pool; moreover, the spraying range of the spray head is large, and a large range of the surface of the cleaning pool can be washed, and the cleaning pool can be washed more comprehensively, so as to effectively reduce the crystallization of chemical droplets formed on the surface of the cleaning pool, and can effectively reduce the defects caused by the adhesion of crystal particles to the surface of the wafer.

[0025] In an alternative embodiment of the present invention, the spray head includes a fan-shaped spray head. The fan-shaped spray head is used to wash the surface of the cleaning pool. The spraying range of the fan-shaped spray head is large, and a large range of the cleaning pool can be washed, reducing the possibility of crystallization on the surface of the cleaning pool. Therefore, the possibility of crystal particles adhering to the surface of the wafer when the wafer is transported in the cleaning machine platform is reduced, the possibility of the wafer generating defects is reduced, and the product yield is improved.

[0026] In an alternative embodiment of the present invention, it further includes: a control module, and the control module is suitable for controlling the spray head to wash the cleaning pool. The spray head washes the cleaning pool under the control of the control module, without manual control, reducing the workload of personnel. Description of the Drawings

[0027] Figure 1 is a top view of a cleaning machine platform;

[0028] Figure 2 is a side view of a cleaning machine platform;

[0029] Figure 3 is a top view of the cleaning machine platform according to the embodiment of the present invention;

[0030] Figure 4 is a side view of the cleaning machine platform according to the embodiment of the present invention;

[0031] Figure 5 is a schematic diagram of the connection relationship between the pneumatic valve and the spray head according to the embodiment of the present invention. Detailed Embodiments

[0032] As can be seen from the background art, there are still problems with the current cleaning machine platform. Now analyze the reasons for its problems:

[0033] Please refer to Figure 1 and Figure 2, a cleaning machine, which is suitable for cleaning wafers after chemical mechanical polishing. The cleaning machine includes:

[0034] A cleaning chamber, in which there is a cleaning pool 100, and the cleaning pool 100 is suitable for containing liquid to clean the wafer;

[0035] A water gun 101, which is arranged above the cleaning pool 100, and the water gun 101 is suitable for flushing the surface of the cleaning pool 100.

[0036] Exemplarily, as Figure 1 shown, the cleaning chamber includes 5 cleaning pools 100 arranged in sequence along the first direction X, and the cleaning pools 100 extend along the second direction Y, and the second direction Y is perpendicular to the first direction X.

[0037] The cleaning pool 100 includes an ultrasonic cleaning pool and a drying pool.

[0038] Specifically, the way of flushing the cleaning chamber with the water gun 101 is: holding the water gun 101 to manually spray the surface of each cleaning pool 100.

[0039] The water gun 101 has a water delivery pipe connected thereto, and the water delivery pipe is suitable for providing water source for the water gun 101.

[0040] Specifically, the number of the water guns 101 is 1.

[0041] The cleaning machine further includes: a drainage trough 102. Along the second direction Y, the water gun 101 is arranged on one side of the cleaning pool 100, and the drainage trough 102 is arranged on the other side of the cleaning pool 100.

[0042] The cleaning machine further includes: an air extraction module, and the air extraction module is suitable for extracting the air in the cleaning chamber.

[0043] During the process of transferring the wafer after chemical mechanical polishing to the cleaning machine, the chemical droplets dripping on the surface of the wafer will adhere to the surface of the cleaning pool 100, and the dripping chemical droplets are likely to form crystals on the surface of the cleaning pool 100. When the wafer is transferred in the cleaning machine, for example, when the wafer is transferred from the ultrasonic cleaning pool to the drying pool, the crystal particles shattered by ultrasonic waves are easily adhered to the surface of the wafer, resulting in the generation of wafer defects and affecting the product yield.

[0044] If the cleaning chamber is cleaned with the water gun 101 of manual spraying, frequent manual flushing operations are required, increasing the tediousness of personnel work. Moreover, when using the water gun 101 for flushing, the spraying range of the water gun 101 is small, and it is impossible to flush the cleaning pool 100 over a large area. There is still a possibility of crystallization in the positions that are not flushed, making it difficult to effectively avoid the adhesion of crystal particles to the surface of the wafer and increasing the possibility of wafer defects.

[0045] To solve the above technical problems, the present invention provides a cleaning machine. The cleaning machine is suitable for cleaning the wafer after chemical mechanical polishing. The cleaning machine includes: a cleaning chamber with a cleaning pool therein. The cleaning pool is suitable for containing liquid to clean the wafer; a spray head arranged in the cleaning chamber, and the spray head sprays liquid towards the cleaning pool to flush the surface of the cleaning pool.

[0046] In the cleaning machine of the technical solution of the present invention, a spray head is arranged in the cleaning chamber of the cleaning machine. The spraying direction of the spray head faces the cleaning pool. The spray head can spray liquid towards the cleaning pool to flush the surface of the cleaning pool, and can remove the chemical droplets dropped on the surface of the cleaning pool from the surface of the wafer after chemical mechanical polishing, so as to reduce the possibility of crystallization on the surface of the cleaning pool. Moreover, the spraying range of the spray head is large, and the surface of the cleaning pool can be flushed over a large area, and the cleaning pool can be flushed more comprehensively, thereby effectively reducing the crystallization of chemical droplets formed on the surface of the cleaning pool, and effectively reducing the defects caused by the adhesion of crystal particles to the surface of the wafer.

[0047] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings.

[0048] Specifically, in some embodiments of the present invention, the wafer is transferred to the cleaning machine by a transfer mechanism for cleaning after chemical mechanical polishing.

[0049] Please refer to Figure 3 and Figure 4 , Figure 3 is the top view of the cleaning machine, Figure 4 is the side view of the cleaning machine. The cleaning machine includes: a cleaning chamber with a cleaning pool 200 therein. The cleaning pool 200 is suitable for containing liquid to clean the wafer.

[0050] Exemplarily, in some embodiments of the present invention, as Figure 3 shown, there are 5 cleaning pools 200 in the cleaning chamber. The 5 cleaning pools 200 are arranged in sequence along the first direction X, and each cleaning pool 200 extends along the second direction Y, and the second direction Y is perpendicular to the first direction X.

[0051] The cleaning tank 200 includes an ultrasonic cleaning tank and a drying tank. Specifically, in some embodiments of the present invention, the cleaning tank 200 is an ultrasonic cleaning tank. In some embodiments, after being cleaned in the ultrasonic cleaning tank, the wafer is transferred to the drying tank for drying.

[0052] Please refer to Figure 3 and Figure 4 , the cleaning machine includes: a spray head 201, the spray head 201 is arranged in the cleaning chamber, and the spray head 201 sprays liquid towards the cleaning tank 200 to wash the surface of the cleaning tank 200.

[0053] During the process of transferring the wafer to the cleaning machine through the transfer mechanism after chemical mechanical polishing, the chemical droplets on the surface of the wafer will drop on the surface of the cleaning tank 200. The liquid sprayed by the spray head 201 can wash the surface of the cleaning tank 200, effectively removing the chemical droplets dropped on the surface of the cleaning tank 200 from the surface of the wafer after chemical mechanical polishing. Moreover, the spraying range of the spray head 201 is large, and it can wash the cleaning tank 200 more comprehensively, thereby effectively reducing the possibility of crystallization on the surface of the cleaning tank 200. Thus, when the wafer is transferred in the cleaning machine, the possibility that the crystallization particles adhere to the surface of the wafer, causing scratches on the surface of the wafer and further resulting in defects of the wafer is reduced.

[0054] Specifically, in some embodiments of the present invention, the spray head 201 is arranged above the cleaning tank 200.

[0055] Specifically, in some embodiments of the present invention, the spray head 201 includes a fan-shaped spray head 201.

[0056] Using the fan-shaped spray head 201 to wash the surface of the cleaning tank 200, the spraying range of the fan-shaped spray head 201 is large, and it can wash the cleaning tank 200 in a large range, reducing the possibility of crystallization on the surface of the cleaning tank 200. Thus, the possibility that the crystallization particles adhere to the surface of the wafer when the wafer is transferred in the cleaning machine is reduced, and the possibility of wafer defects is reduced, improving the product yield.

[0057] Specifically, in some embodiments of the present invention, the number of the spray heads 201 is at least two, and the at least two spray heads 201 are arranged on the same side of the cleaning tank 200. That is, along the second direction Y, the at least two spray heads 201 are arranged on the same side of the cleaning tank 200.

[0058] Specifically, in some embodiments of the present invention, among the at least two spray heads 201, the distance between adjacent spray heads 201 is equal.

[0059] Please refer to Figure 5 , the cleaning machine further includes: a water delivery pipe adapted to be connected to the spray head 201 to supply the liquid to the spray head 201.

[0060] The water delivery pipe includes a branch water pipe 202 and a main water pipe 203. The branch water pipe 202 has an opposite end 202a and an opposite end 202b. One end 202a of the branch water pipe 202 is connected to the spray head 201, and the other end 202b of the branch water pipe 202 is connected to the main water pipe 203. The main water pipe 203 is connected to at least one branch water pipe 202 to supply the liquid to each branch water pipe 202.

[0061] One end 202a of the branch water pipe 202 is connected to the spray head 201. The number of the branch water pipes 202 is adapted to the number of the spray heads 201. Specifically, in some embodiments of the present invention, the number of the spray heads 201 is 2, and the number of the branch water pipes 202 is 2.

[0062] The cleaning machine further includes: a pneumatic valve 204 adapted to pressurize the liquid.

[0063] The pneumatic valve 204 is a device that uses compressed air as a power source to drive the valve to act. Pressurizing with the pneumatic valve 204 has a convenient power source, and the control accuracy of the flow rate and pressure of the fluid is high when pressurizing with the pneumatic valve 204.

[0064] Specifically, in some embodiments of the present invention, please refer to Figure 5 , the pneumatic valve 204 includes a first end A, a second end B, and a third end C. The first end A is adapted to be connected to the water delivery pipe, the second end B is adapted to be connected to the spray head 201, and the third end C is adapted to be connected to the air source.

[0065] Specifically, the first end A is connected to the branch water pipe 202.

[0066] Please continue to refer to Figure 3 and Figure 4 , the cleaning machine further includes: a drain trough 206 adapted to receive the liquid for flushing the cleaning tank 200.

[0067] Specifically, in some embodiments of the present invention, the spray head 201 is arranged on one side of the cleaning tank 200 along the second direction Y, and the drain trough 206 is arranged on the other side of the cleaning tank 200 along the second direction Y.

[0068] The drain trough 206 and the spray head 201 are disposed on opposite sides of the cleaning pool 200, such that the liquid can fully rinse the surface of the cleaning pool 200, which is beneficial to reducing the crystallization of chemical droplets on the surface of the cleaning pool 200 and improving the rinsing effect.

[0069] Specifically, please continue to refer to Figure 3 and Figure 4 , the surface of the cleaning pool 200 on the side close to the spray head 201 is higher than the surface of the cleaning pool 200 on the side close to the drain trough 206, that is, the surface of one side 200a of the cleaning pool 200 is higher than the surface of the other side 200b of the cleaning pool 200, such that the liquid for rinsing the cleaning pool 200 can flow along the side of the spray head 201 to the drain trough 206, so as to fully rinse the cleaning pool 200.

[0070] Specifically, in some embodiments of the present invention, along the direction Y pointing from the side close to the spray head 201 to the side close to the drain trough 206, the surface of the cleaning pool 200 gradually decreases. Exemplarily, please refer to Figure 4 , along the direction Y from one side 200a of the cleaning pool 200 to the other side 200b of the cleaning pool 200, the surface of the cleaning pool 200 gradually decreases.

[0071] Specifically, please continue to refer to Figure 3 , along the extending direction X of the drain trough 206, the drain trough 206 has an opposite end and another end, the bottom surface of one end of the drain trough 206 is higher than the bottom surface of the other end of the drain trough 206, such that the liquid for rinsing the cleaning pool 200 can be discharged from the other end with a lower bottom surface of the drain trough 206.

[0072] Specifically, in some embodiments of the present invention, along the extending direction X of the drain trough 206, the bottom surface of the drain trough 206 gradually decreases.

[0073] The cleaning machine platform further includes: a control module, and the control module is adapted to control the spray head 201 to rinse the cleaning pool 200.

[0074] The spray head 201 rinses the cleaning pool 200 under the control of the control module, without manual control, reducing the workload of personnel.

[0075] The cleaning machine platform further includes: an air extraction module, and the air extraction module is suitable for extracting the air in the cleaning room.

[0076] The air extraction device can extract the air inside the cleaning machine platform, reduce the air pressure, reduce the number of suspended particles in the air, create a relatively clean working environment, and avoid introducing new pollutants during the cleaning process.

[0077] Correspondingly, the present invention further provides a chemical mechanical polishing system, including: a polishing machine platform adapted to perform chemical mechanical polishing on a wafer; a cleaning machine platform as described in any one of the above, the cleaning machine platform being adapted to clean the wafer after chemical mechanical polishing; and a transfer mechanism adapted to transfer the wafer from the polishing machine platform to the cleaning machine platform.

[0078] Correspondingly, the present invention further provides a control method for a cleaning machine platform, the cleaning machine platform being as described in any one of the above; the control method includes: after the cleaning machine platform cleans a batch of wafers, and before the cleaning machine platform cleans the next batch of wafers, causing the spray head 201 to spray out the liquid to wash the surface of the cleaning pool 200.

[0079] That is, during the time interval when the cleaning machine platform has cleaned a batch of wafers and has not yet cleaned the next batch of wafers, when the cleaning machine platform is in an idle state, the spray head 201 washes the surface of the cleaning pool 200 under the control of the control module.

[0080] Specifically, the number of wafers in a batch of wafers and the next batch of wafers referred to here are determined according to the actual requirements of the process.

[0081] Specifically, in some embodiments of the present invention, the duration for the cleaning machine platform to clean a batch of wafers is a first duration, and the control module is adapted to control the spray head 201 to wash the surface of the cleaning pool 200 once every first duration. The control method reduces the possibility of crystallization on the surface of the cleaning pool 200, thereby reducing the possibility that crystal particles adhere to the surface of the wafer during the transfer of the wafer between the cleaning pools, causing defects in the wafer; and, the control method causes the spray head 201 to clean the cleaning pool 200 once every first duration, eliminating the need for frequent manual flushing operations and reducing the workload of personnel.

[0082] In summary, the spray head 201 is disposed in the cleaning chamber, and the spray head 201 sprays liquid towards the cleaning pool 200 to wash the surface of the cleaning pool 200. The spray head 201 can spray liquid towards the cleaning pool 200 to wash the surface of the cleaning pool, which can remove the chemical droplets dropped on the surface of the cleaning pool 200 from the surface of the wafer after chemical mechanical polishing, reducing the possibility of crystallization on the surface of the cleaning pool 200; moreover, the spraying range of the spray head 201 is large, and the surface of the cleaning pool 200 can be washed in a large range, and the cleaning pool 200 can be washed more comprehensively, thereby effectively reducing the crystallization of chemical droplets formed on the surface of the cleaning pool 200, and effectively reducing the defects caused by the adhesion of crystal particles to the surface of the wafer; in addition, the spray head 201 cleans the cleaning pool 200 under the control of the control module, without the need for manual flushing operation, reducing the workload of personnel.

[0083] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A cleaning machine, which is suitable for cleaning wafers after chemical mechanical polishing, characterized in that: The cleaning machine comprises: A cleaning chamber, wherein the cleaning chamber has a cleaning pool, and the cleaning pool is suitable for containing liquid to clean the wafer; A spray head is arranged in the cleaning room, and the spray head sprays liquid toward the cleaning pool to rinse the surface of the cleaning pool.

2. The cleaning machine according to claim 1, characterized in that: The spray head comprises a fan-shaped spray head.

3. The cleaning machine according to claim 1, characterized in that: Also includes: A water delivery pipe is suitable for being connected to the sprinkler head to provide the liquid to the sprinkler head.

4. The cleaning machine according to claim 1, characterized in that: Also includes: A pneumatic valve is provided, wherein the pneumatic valve is adapted to pressurize the liquid.

5. The cleaning machine according to claim 4, characterized in that: The pneumatic valve comprises a first end, a second end and a third end, wherein the first end is suitable for being connected to a water pipe, the second end is suitable for being connected to the sprinkler head, and the third end is suitable for being connected to an air source.

6. The cleaning machine according to claim 1, characterized in that: Also includes: A drainage trough is suitable for receiving liquid for flushing the cleaning pool.

7. The cleaning machine according to claim 6, characterized in that: The spray head is arranged on one side of the cleaning pool; the drainage trough is arranged on the other side of the cleaning pool.

8. The cleaning machine according to claim 7, characterized in that: The surface of the cleaning pool on the side close to the shower head is higher than the surface of the cleaning pool on the side close to the drainage groove.

9. The cleaning machine according to claim 8, characterized in that: The surface of the cleaning pool gradually decreases along a direction from a side close to the spray head to a side close to the drainage groove.

10. The cleaning machine according to claim 7, characterized in that: The drainage groove has one end and the other end opposite to each other along an extending direction of the drainage groove, and a bottom surface of the one end of the drainage groove is higher than a bottom surface of the other end of the drainage groove.

11. The cleaning machine according to claim 10, characterized in that: Along the extending direction of the drainage groove, the bottom surface of the drainage groove gradually decreases.

12. The cleaning machine according to claim 1, characterized in that: The number of the spray heads is at least 2, and the at least 2 spray heads are arranged on the same side of the cleaning pool.

13. The cleaning machine according to claim 1, characterized in that: Also includes: A control module is provided, wherein the control module is suitable for controlling the spray head to flush the cleaning pool.

14. The cleaning machine according to claim 1, characterized in that: Also includes: An air extraction module is adapted to extract air from the clean room.

15. The cleaning machine according to claim 1, characterized in that: The cleaning pool is an ultrasonic cleaning pool.

16. A chemical mechanical polishing system, characterized in that: include: A grinding machine, wherein the grinding machine is suitable for chemical mechanical grinding of wafers; The cleaning machine according to any one of claims 1 to 15, wherein the cleaning machine is suitable for cleaning wafers after chemical mechanical polishing; The conveying mechanism is suitable for conveying the wafer from the grinding machine to the cleaning machine.

17. A method for controlling a cleaning machine, characterized in that: The cleaning machine is as described in any one of claims 1 to 15; The control method comprises: After the cleaning machine cleans a batch of wafers, and before the cleaning machine cleans the next batch of wafers, the shower head sprays liquid to rinse the surface of the cleaning pool.

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