TWI721080B - Device for cleaning substrate and high temperature chemical solution supply system - Google Patents

Abstract

The invention discloses a high-temperature chemical solution supply system for cleaning a substrate. The system includes a solution tank, a buffer tank, a first pump and a second pump. The solution tank contains high-temperature chemical solutions. The buffer tank has a tank body, an exhaust pipe and a needle valve. The tank contains a high-temperature chemical solution. One end of the exhaust pipe is connected to the tank body, and the other end of the exhaust pipe is connected to the solution tank. The needle valve is installed on the exhaust pipe, and the air bubbles in the high-temperature chemical solution are discharged from the buffer tank through the exhaust pipe by adjusting the needle valve to achieve a flow rate. The inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected to the buffer tank. The inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate. The invention also provides a substrate cleaning device including a high-temperature chemical solution supply system and an ultrasonic/megasonic device. The invention also provides a method for cleaning the substrate.

Description

Device for cleaning substrate and high temperature chemical solution supply system

The present invention relates to substrate cleaning methods and devices, and in particular to reducing bubbles in high-temperature chemical solutions such as SC1, and reducing bubbles generated or accumulated during substrate cleaning in a single-chip cleaning machine with ultrasonic devices when high-temperature chemical solutions are supplied.

In the semiconductor device manufacturing process, particles on the surface of the substrate need to be removed or cleaned before proceeding to the next step. For example, after CMP (Chemical Mechanical Planarization), the polishing liquid and residues on the surface of the substrate are very difficult to remove. Usually high temperature sulfuric acid (SPM) is used to remove these particles. However, sulfuric acid is not only difficult to operate safely, but also the waste liquid treatment of sulfuric acid is very expensive. Hot SC1 (including hydrogen peroxide, ammonia and water) is a very good choice to replace hot sulfuric acid, but in order to effectively remove particles, the temperature of SC1 needs to be heated to above 80°C.

When SC1 reaches such a high temperature, SC1 chemicals are easily decomposed into oxygen and ammonia through low-pressure suction, mechanical agitation and heating of the hydrogen peroxide and ammonia in SC1. These SC1 mixed with bubbles can easily cause the loss of functions of pumps, heaters, flow meters and ultrasonic equipment during the cleaning process.

Therefore, in the process of mixing, heating, conveying and final cleaning, At the same time, when ultrasonic energy is applied to the substrate, a better method is needed to control the bubbles in the high-temperature chemical solution.

The present invention provides a high-temperature chemical solution supply system for cleaning substrates. The system includes a solution tank, a buffer tank, a first pump and a second pump. The solution tank contains high-temperature chemical solutions. The buffer tank has a tank body, an exhaust pipe and a needle valve. The tank body contains high-temperature chemical solutions. One end of the exhaust pipe is connected to the tank body, and the other end of the exhaust pipe is connected to the solution tank. The needle valve is installed on the exhaust pipe. By adjusting the needle valve to achieve a flow rate, the bubbles in the high-temperature chemical solution are discharged from the buffer tank through the exhaust pipe. The inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected to the buffer tank. The inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate.

The invention also provides a device for cleaning the substrate. The device includes a solution tank, a buffer tank, a first pump, a second pump, a substrate chuck, a rotary drive device, a nozzle, an ultrasonic/megasonic wave device, and a vertical drive. The solution tank contains high-temperature chemical solutions. The buffer tank has a tank body, an exhaust pipe and a needle valve. The tank body contains high-temperature chemical solutions. One end of the exhaust pipe is connected to the tank body, and the other end of the exhaust pipe is connected to the solution tank. The needle valve is installed on the exhaust pipe. By adjusting the needle valve to achieve a flow rate, the bubbles in the high-temperature chemical solution are discharged from the buffer tank through the exhaust pipe. The inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected to the buffer tank. The inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate. The substrate chuck carries the substrate. The rotation driving device is connected to the substrate chuck and drives the substrate chuck to rotate. The nozzle sprays on the substrate surface High temperature chemical solution or deionized water. The ultrasonic/megasonic device is arranged close to the substrate, and there is a gap between the ultrasonic/megasonic device and the substrate. The vertical driver drives the ultrasonic/megasonic device up or down to change the gap between the substrate and the ultrasonic/megasonic device.

The present invention provides a method for cleaning a substrate, which includes: rotating the substrate; spraying deionized water on the surface of the substrate to pre-wet the surface of the substrate; spraying a high-temperature chemical solution on the surface of the substrate to clean the surface of the substrate; Reduce the speed to a low speed, and move the ultrasonic/megasonic device close to the surface of the substrate. There is a gap d between the ultrasonic/megasonic device and the substrate surface, and the high-temperature chemical solution completely fills the gap d; turn on the ultrasonic/megasonic device, and Provide a constant or pulse working power during a cleaning cycle; turn off the ultrasonic/megasonic device, spray high-temperature chemical solution or deionized water on the surface of the substrate to release the bubbles generated by the ultrasonic/megasonic device to prevent bubbles from gathering on the surface of the substrate; turn on the ultrasonic / Megasonic device, and provide constant or pulse working power in the second cleaning cycle; turn off the ultrasonic / megasonic device, spray chemical liquid or deionized water on the surface of the substrate; dry the substrate.

The present invention also provides a method for cleaning a substrate, including: rotating the substrate; spraying deionized water on the surface of the substrate to pre-wet the surface of the substrate; spraying a high-temperature chemical solution on the surface of the substrate to clean the surface of the substrate; Reduce the speed to a low speed, and move the ultrasonic/megasonic device close to the surface of the substrate. There is a gap d between the ultrasonic/megasonic device and the substrate surface, and the high-temperature chemical solution completely fills the gap d; turn on the ultrasonic/megasonic device, and The first cleaning cycle provides constant or pulse working power; turn off the ultrasonic/megasonic device, raise the ultrasonic/megasonic device, and make the ultrasonic/megasonic device leave the high Warm the surface of the chemical solution to release the bubbles that have gathered under or around the ultrasonic/megasonic device; move the ultrasonic/megasonic device down with a gap d between the ultrasonic/megasonic device and the surface of the substrate, and then turn on the ultrasonic/megasonic device , And provide constant or pulse working power in the second cleaning cycle; turn off the ultrasonic/megasonic device, spray chemical liquid or deionized water on the surface of the substrate; dry the substrate.

The present invention also provides a method for cleaning a substrate, including: rotating the substrate; spraying deionized water on the surface of the substrate to pre-wet the surface of the substrate; spraying a high-temperature chemical solution or deionized water on the surface of the substrate to clean the surface of the substrate ; Spray a medium-temperature chemical solution or deionized water to the surface of the substrate to clean the surface of the substrate; reduce the speed of the substrate to a low speed, and move the ultrasonic/megasonic device close to the surface of the substrate to cooperate with the medium-temperature chemical solution , The cleaning chemical solution completely fills the gap d between the ultrasonic/megasonic device and the surface of the substrate; turn on the ultrasonic/megasonic device, and provide a constant or pulse working power during the first cleaning cycle; spray a medium-temperature chemical solution on the surface of the substrate Or deionized water to release the bubbles generated by the medium-temperature chemical solution to prevent bubbles from accumulating on the surface of the substrate; turn on the ultrasonic/megasonic device and provide a constant or pulsed power supply during the second cleaning cycle; turn off the ultrasonic/megasonic device to Spray chemical liquid or deionized water on the surface of the substrate; dry the substrate.

1003: Bellows pump

1033: Left Bellows Chamber

1035: right bellows room

1037: Bubble

2019: the first pump

2021: buffer slot

2022: tank

2023: second pump

2028: Inlet pipe

2029: Needle Valve

2030: Exhaust pipe

2032: Outlet pipe

2034: Bubble divider

2036: Particulate filter

2037: bubbles

3035: second buffer slot

3053: Fourth pump

4001: Solution tank

4003: The third pump

4005: Thermometer

4007: Drain pipe

4008: Controller

4009: Third Import

4013: heater

4015: second import

4017: first import

4019: The first pump

4021: Buffer slot

4023: second pump

4029: Needle valve

4030: Exhaust pipe

5003: Ultrasonic/Megasonic device

5004: Piezoelectric sensor

5005: Lead screw

5006: vertical drive

5007: Support beam

5008: Acoustic Resonator

5010: Substrate

5012: nozzle

5014: Substrate chuck

5016: Drive

5032: Chemical solution (deionized water)

5088: control unit

Figures 1A-1B describe the working process of the bellows pump of an exemplary embodiment; Figures 2A-2D describe an embodiment of a system with one buffer tank and two pumps; Figure 3 describes an embodiment of a system with two buffer tanks and three pumps; Figure 4 describes the mixing, heating, and heating of high-temperature chemicals. An embodiment of a conveying system; Figures 5A-5B depict an embodiment of a substrate cleaning device with an ultrasonic/megasonic device.

The invention provides a high-temperature chemical solution supply system for cleaning substrates. The system includes a solution tank, a buffer tank, a first pump and a second pump. The solution tank contains high-temperature chemical solutions. The buffer tank has a tank body, an exhaust pipe and a needle valve. The tank body contains high-temperature chemical solutions. One end of the exhaust pipe is connected to the tank body, and the other end of the exhaust pipe is connected to the solution tank. The needle valve is installed on the exhaust pipe and can be adjusted through The needle valve reaches a flow rate so that the bubbles in the high-temperature chemical solution are discharged out of the buffer tank through the exhaust pipe. The inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected to the buffer tank. The inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate.

The invention also provides a device for cleaning the substrate. The device includes a solution tank, a buffer tank, a first pump, a second pump, a substrate chuck, a rotary drive device, a nozzle, an ultrasonic/megasonic wave device, and a vertical drive. The solution tank contains high-temperature chemical solutions. The buffer tank has a tank body, an exhaust pipe and a needle valve. The tank body contains high-temperature chemical solutions. One end of the exhaust pipe is connected to the tank body, and the other end of the exhaust pipe is connected to the solution tank. The needle valve is installed on the exhaust pipe and can be adjusted through Needle valve At a flow rate, the bubbles in the high-temperature chemical solution are discharged out of the buffer tank through the exhaust pipe. The inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected to the buffer tank. The inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate. The substrate chuck carries the substrate. The rotation driving device is connected to the substrate chuck and drives the substrate chuck to rotate. The nozzle sprays a high-temperature chemical solution or deionized water on the surface of the substrate. The ultrasonic/megasonic device is arranged close to the substrate, and there is a gap between the ultrasonic/megasonic device and the substrate. The vertical driver drives the ultrasonic/megasonic device up or down to change the gap between the substrate and the ultrasonic/megasonic device.

Figures 1A-1B illustrate the working principle of a common bellows pump. The bellows pump 1003 includes a left bellows chamber 1033 and a right bellows chamber 1035. As shown in Figure 1A, when air is discharged, the left bellows chamber 1033 sucks in liquid. When the liquid is a high-temperature chemical, such as SC1 with a temperature higher than 70°C, bubbles 1037 (mainly It is the oxygen and ammonia that are decomposed by hydrogen peroxide and ammonia). In the next pumping cycle, when air is supplied, the bubbles 1037 mixed with the chemical solution in the left bellows chamber 1033 will be pushed out of the left bellows chamber 1033, as shown in FIG. 1B. The bubble 1037 will be compressed to a smaller volume. Therefore, the pressure of the liquid at the outlet of the pump 1003 will be significantly reduced. In addition, the chemical solution mixed with bubbles 1037 will cause the function of the pump, heater, flow meter, and ultrasonic equipment to be lost during the cleaning process.

Figures 2A-2D show a specific embodiment of the pump system according to the present invention. As shown in FIG. 2A, the system includes a first pump 2019, a buffer tank 2021, a second pump 2023, a needle valve 2029, and an exhaust pipe 2030. The chemical solution pumped from the first pump 2019 includes the above-mentioned bubbles. These and chemistry The air bubbles mixed with the solution will be pumped into the buffer tank 2021. In the buffer tank 2021, air bubbles rise to the top of the buffer tank 2021, and then are discharged through the needle valve 2029 and the exhaust pipe 2030. The needle valve 2029 needs to be adjusted to be sufficient to expel most of the bubbles, while not being able to release too much pressure in the buffer tank 2021. By adjusting the output pressure of the first pump 2019, the pressure range in the buffer tank 2021 is between 5 psi and 20 psi, preferably 10 psi. Then, the chemical solution with a few bubbles in the buffer tank 2021 is pressed into the inlet of the second pump 2023. Since the chemical solution pressed into the inlet of the second pump 2023 has a certain pressure (approximately set to 10 psi), fewer or fewer bubbles will be generated during the suction process of the second pump 2023. Therefore, the pressure at the outlet of the second pump 2023 can be maintained at a high value, and the pressure at the outlet of the second pump 2023 can be set as high as 20-50 psi. Generally, the first pump 2019 can be a centrifugal pump or a bellows pump. The second pump 2023 preferably uses a bellows pump to obtain a higher pressure output.

Fig. 2B shows a specific embodiment of the buffer tank according to the present invention. The buffer tank has a tank body 2022, a liquid inlet pipe 2028, a needle valve 2029, an exhaust pipe 2030, and a liquid outlet pipe 2032. The liquid inlet pipe 2028 and the liquid outlet pipe 2032 are inserted near the bottom of the tank body 2022, and the exhaust pipe 2030 is installed at the top of the buffer tank 2021, and bubbles 2037 in the chemical solution rise and exit the buffer tank 2021 through the exhaust pipe 2030.

Fig. 2C shows another specific embodiment of the buffer tank according to the present invention. The buffer tank is similar to that in FIG. 2B, except that the buffer tank 2021 also includes a bubble separator 2034. The function of the bubble separator 2034 is to prevent bubbles 2037 output from the inlet pipe 2028 from entering the outlet pipe. 2032. The height of the bubble separator 2034 is 50%-80% of the height of the buffer tank, preferably 70%.

Fig. 2D shows another specific embodiment of the buffer tank according to the present invention. The buffer tank is similar to that in FIG. 2B except that the buffer tank 2021 further includes a particle filter 2036. The liquid outlet pipe 2032 is installed at the top of the buffer tank 2021 and is located at the outlet of the particle filter 2036. The liquid inlet pipe 2028 is inserted into a position close to the bottom of the tank body 2022 and located at the inlet of the particle filter 2036. The exhaust pipe 2030 is installed at the top of the buffer tank 2021 and is located at the inlet of the particulate filter 2036. The function of the particle filter 2036 is to prevent the bubbles 2037 from directly entering the outlet pipe 2032 through the filter membrane, and the bubbles 2037 blocked by the filter membrane are discharged through the exhaust pipe 2030 and the needle valve 2029.

Fig. 3 shows another specific embodiment of the pump system according to the present invention. The system is similar to that shown in FIG. 2A, except that the system also includes a second buffer tank 3035 and a fourth pump 3053. Compared with the two-pump system, the three-pump system can make the chemicals have a greater pressure and a greater flow rate at a higher temperature. Obviously, more pumps and buffer tanks can be combined to achieve greater pressure and greater flow.

Fig. 4 shows a specific embodiment of the hot chemical solution supply system according to the present invention. The liquid supply system includes a solution tank 4001, a first pump 4019, a buffer tank 4021, a second pump 4023, a third pump 4003, a heater 4013, a thermometer 4005 and a controller 4008. The solution tank 4001 is provided with a first inlet 4017 for inlet of water, a second inlet 4015 for inlet of a first chemical liquid such as hydrogen peroxide, and a third inlet 4009 for inlet of a second chemical liquid such as ammonia. The solution tank 4001 further includes a chemical solution for discharging the solution The drain pipe 4007 of the liquid tank 4001. The outer surface of the solution tank 4001 is wrapped with thermal insulation material such as rubber or foam plastic for heat preservation, and all are connected to the solution tank 4001, the first pump 4019, the buffer tank 4021, the second pump 4023, the third pump 4003 and the heater 4013. The liquid pipes in the middle are all wrapped with the same insulation material.

The working steps of the high-temperature chemical solution supply system are as follows: Step 1: Inject the required amount of water (deionized water) into the solution tank 4001. In order to shorten the heating time, if the temperature of the final mixed chemical solution needs to reach 60°C or higher, You can inject hot water with a temperature of 60°C; Step 2: Inject the first chemical solution of the required concentration, such as hydrogen peroxide; Step 3: Inject the second chemical solution of the required concentration, such as ammonia; Step 4: Turn on the first chemical solution Three pumps 4003, the air pressure is set at 20-60psi, preferably 40psi; Step 5: Turn on the heater 4013, set the temperature to T0, the temperature can be set between 35℃-95℃; Step 6: When the thermometer 4005 shows the solution When the temperature of the chemical solution in the tank 4001 reaches the set temperature T0, turn on the first pump 4019 and set the output pressure P1 between 5-30 psi, preferably 15 psi; Step 7: Adjust the needle valve 4029 to reach a flow just enough to discharge Bubbles, in order to save the chemical solution, the discharged bubbles mixed with the mixed chemical solution such as SC1 will return to the solution tank 4001 through the exhaust pipe 4030; Step 8: Turn on the second pump 4023, and set the output pressure P2 at 10-80 psi And P2 is greater than P1; Step 9: Since the second pump 4023 is opened, the pressure P1 may change It will affect the flow rate of the exhaust pipe 4030. Therefore, readjust the needle valve 4029 to achieve a flow rate just enough to discharge air bubbles.

Figures 5A-5B show a specific embodiment of a substrate cleaning device with an ultrasonic/megasonic device. The substrate cleaning device includes a substrate 5010, a substrate chuck 5014 that is rotated by a rotating drive device 5016, a nozzle 5012 for spraying a chemical solution or deionized water 5032, and an ultrasonic/megasonic (ultrasonic running at a frequency of MHZ) device 5003. The ultrasonic/megasonic device 5003 also includes a piezoelectric sensor 5004 and an acoustic resonator 5008 paired therewith. After the sensor 5004 is energized, it acts like vibration, and the resonator 5008 transfers high-frequency sound energy to the chemical solution or deionized water 5032. The vibration generated by megasonic energy loosens the particles on the substrate 5010, and then removes them from the surface of the substrate 5010 through the flowing chemical solution or deionized water 5032 provided by the nozzle 5012.

The substrate cleaning device also includes a supporting beam 5007, a lead screw 5005 and a vertical driver 5006. The gap d between the ultrasonic/megasonic device 5003 and the substrate 5010 increases or decreases as the substrate chuck 5014 rotates during the cleaning process. The control unit 5088 controls the speed of the vertical driver 5006 based on the speed of the rotation driving device 5016.

In a specific embodiment, the gap d is controlled to release the bubbles accumulated under or around the ultrasonic/megasonic device 5003. The gap d between the ultrasonic/megasonic device 5003 and the surface of the substrate 5010 is sufficiently high, so that the working surface of the ultrasonic/megasonic device 5003 is not immersed in the cleaning chemical solution 5032.

With ultrasonic/megasonic input to the substrate 5010 and ultrasonic In the gap between the megasonic device 5003, high temperature chemical solutions such as SC1 with a temperature exceeding 70°C will generate bubbles, which will increase the reflected power of the ultrasonic/ megasonic device, which will cause the ultrasonic/ megasonic power to shut down. At the same time, the gap A small amount of ultrasonic/mega-sonic power in the medium will reduce the cleaning effect of the substrate 5010. In addition, the bubbles on the surface of the substrate 5010 may prevent the chemical solution and ultrasonic/megasonic waves from contacting the substrate 5010, thereby causing uncleaned areas and defects on the substrate 5010.

In order to reduce the bubbles generated in the ultrasonic/megasonic assisted cleaning process, the cleaning process is divided into several stages to reduce bubbles.

The specific method provided by the present invention includes the following steps:

Step 1: The substrate chuck 5014 drives the substrate 5010 to rotate, and the rotation speed is set to 300-1200 rpm, preferably 500 rpm;

Step 2: Use a nozzle 5012 to spray deionized water on the surface of the substrate 5010 to pre-wet the surface of the substrate 5010;

Step 3: Use the nozzle 5012 to spray a high-temperature (greater than 70°C) chemical solution such as SC1 on the surface of the substrate 5010 to clean the surface of the substrate 5010;

Step 4: Reduce the speed of the substrate to a low speed (10-200 rpm), and move the ultrasonic/megasonic device to a position close to the surface of the substrate 5010 with a gap d between the surface of the substrate 5010. The chemical solution completely fills the gap d between the surface of the substrate 5010 and the ultrasonic/megasonic device 5003, so that the working surface of the ultrasonic/megasonic device 5003 is immersed in the chemical solution;

Step 5: Turn on the ultrasonic/megasonic device 5003 and provide a constant or pulse working power during the first cleaning cycle. In this step, the gap d is driven vertically Actuator 5006 control; the waveform of the ultrasonic/megasonic power supply is programmable and preset according to the formula, and the track of the gap d change is also programmable and preset according to the formula.

Step 6: Turn off the ultrasonic/megasonic device. Spray a high-temperature chemical solution or deionized water on the surface of the substrate 5010 to release bubbles generated by the ultrasonic/megasonic device in step 5 to prevent bubbles from accumulating on the surface of the substrate; in this bubble release step, the type of chemical solution sprayed can be It is the same as or different from the cleaning chemical solution.

The sprayed chemical solution completely fills the gap d between the surface of the substrate and the ultrasonic/megasonic device, so that the working surface of the ultrasonic/megasonic device is immersed in the chemical solution.

The rotation speed of the substrate can be set higher to better release the bubbles.

The gap d can be set larger to better release the bubbles.

The power supply of the ultrasonic/megasonic device can be set lower or completely closed to better release the air bubbles.

For production considerations, the time of the bubble release step can be set to a few seconds.

Step 7: Turn on the ultrasonic/megasonic device 5003 and provide a constant or pulse power supply in the second cleaning cycle. In this step, the gap d is controlled by the vertical driver 5006; the waveform of the ultrasonic/megasonic power supply is programmable and pre-designed according to the formula. It is assumed that the trajectory of the gap d change is also programmable and preset according to the formula.

Steps 6 and 7 can be repeated continuously to enhance the cleaning effect.

The first cleaning cycle and the second cleaning cycle are repeated many times, in every two A bubble release step is set between the cleaning cycles. The first cleaning cycle and the second cleaning cycle can be the same or different.

Step 8: Turn off the ultrasonic/megasonic device 5003, and use the nozzle 5012 to spray chemical liquid or deionized water on the substrate 5010;

Step 9: Dry the substrate 5010.

Another method provided by the present invention for preventing bubbles from being generated in the ultrasonic/megasonic wave assisted cleaning process includes the following steps:

Step 1: The substrate chuck 5014 drives the substrate 5010 to rotate, and the rotation speed is set to 300-1200 rpm, preferably 500 rpm.

Step 2: Use a nozzle 5012 to spray deionized water on the surface of the substrate 5010 to pre-wet the surface of the substrate 5010;

Step 3: Use the nozzle 5012 to spray a high temperature (greater than 70°C) chemical solution such as SC1 on the surface of the substrate 5010 to clean the surface of the substrate 5010;

Step 4: Reduce the speed of the substrate to a low speed (10-200rpm), move the ultrasonic/megasonic device 5003 to a position close to the surface of the substrate 5010 and have a gap d between the surface of the substrate 5010, and the chemical solution is completely filled The gap between the surface of the substrate 5010 and the ultrasonic/megasonic device 5003, so that the working surface of the ultrasonic/megasonic device 5003 is immersed in the chemical solution;

Step 5: Turn on the ultrasonic/megasonic device 5003 and provide a constant or pulse working power supply in the first cleaning cycle. In this step, the gap d is controlled by the vertical drive 5006; The waveform of the ultrasonic/megasonic power supply is programmable and preset according to the formula, and the track of the gap d change is also programmable and preset according to the formula.

Step 6: Turn off the ultrasonic/megasonic device, and then raise the ultrasonic/megasonic device to make the ultrasonic/megasonic device leave the surface of the high-temperature chemical solution to release the bubbles that have gathered under or around the ultrasonic/megasonic device.

In this bubble release step, the sprayed chemical solution may be the same as or different from the cleaning chemical solution.

The ultrasonic/megasonic device is raised, and the gap d between the ultrasonic/megasonic device and the substrate surface is sufficiently high, so the working surface of the ultrasonic/megasonic device is not immersed in the cleaning chemical solution.

The rotation speed of the substrate can be set higher to better release the bubbles.

The power supply of the ultrasonic/megasonic device can be set lower or completely closed to better release the air bubbles.

For production considerations, the time of the bubble release step can be set to a few seconds.

Step 7: Move the ultrasonic/megasonic device 5003 downwards so that there is a gap d between the ultrasonic/megasonic device and the substrate 5010, and then turn on the ultrasonic/megasonic device 5003 and provide a constant or pulse operating power during the second cleaning cycle. In this step, the gap d is controlled by the vertical driver 5006.

The waveform of the ultrasonic/megasonic power supply is programmable and preset according to the formula, and the track of the gap d change is also programmable and preset according to the formula.

Steps 6 and 7 can be repeated continuously to enhance the cleaning effect.

The first cleaning cycle and the second cleaning cycle are repeated multiple times, and a bubble release step is set between every two cleaning cycles. The first cleaning cycle and the second cleaning cycle can be the same or different.

Step 8: Turn off the ultrasonic/megasonic device 5003, and apply to the substrate 5010 Spray chemical liquid or deionized water.

Step 9: Dry the substrate 5010.

Another method provided by the present invention for preventing bubbles from being generated in the ultrasonic/megasonic assisted cleaning process includes the following steps:

Step 1: The substrate chuck 5014 drives the substrate 5010 to rotate, and the rotation speed is set to 300-1200 rpm, preferably 500 rpm.

Step 2: Use the nozzle 5012 to spray deionized water on the surface of the substrate 5010 to pre-wet the surface of the substrate 5010.

Step 3: Use a scanning nozzle to spray a high-temperature chemical solution or deionized water on the surface of the substrate 5010. The scanning path is programmable and set according to the formula.

Step 4: Spray a medium temperature chemical solution (25° C.-70° C.) or deionized water on the surface of the substrate 5010 to clean the surface of the substrate 5010.

The type of the medium temperature chemical solution and the type of the high temperature chemical solution may be the same or different.

Step 5: Decrease the speed of the substrate to a low speed (10-500rpm), move the ultrasonic/megasonic device 5003 to a position close to the surface of the substrate 5010, and cooperate with the medium temperature chemical solution to completely fill the ultrasonic/ The gap d between the megasonic device and the surface of the substrate, so that the working surface of the ultrasonic/megasonic device is immersed in the chemical solution.

Step 6: Turn on the ultrasonic/megasonic device and provide a constant or pulse operating power during the first cleaning cycle. In this step, the gap d is controlled by the vertical drive.

The waveform of the ultrasonic/megasonic power supply is programmable and according to the formula By default, the trajectory of the gap d change is also programmable and preset according to the formula.

Step 7: Spray a medium-temperature chemical solution or deionized water on the surface of the substrate to release bubbles generated by the medium-temperature chemical solution, thereby preventing bubbles from accumulating on the surface of the substrate.

In this bubble release step, the type of chemical solution sprayed may be the same as or different from the type of cleaning chemical solution.

The rotation speed of the substrate can be set higher to better release the bubbles.

The gap d can be set larger to better release the bubbles.

The power supply of the ultrasonic/megasonic device can be set lower or completely closed to better release the air bubbles.

For production considerations, the time of the bubble release step can be set to a few seconds.

Step 8: Turn on the ultrasonic/megasonic device and provide a constant or pulse operating power during the second cleaning cycle. In this step, the gap d is controlled by the vertical drive.

The waveform of the ultrasonic/megasonic power supply is programmable and preset according to the formula, and the track of the gap d change is also programmable and preset according to the formula.

Steps 7 and 8 can be repeated continuously to enhance the cleaning effect.

The first cleaning cycle and the second cleaning cycle are repeated multiple times, and a bubble release step is set between every two cleaning cycles. The first cleaning cycle and the second cleaning cycle may be the same or different.

Step 9: Turn off the ultrasonic/megasonic device, and spray chemical liquid or deionized water on the substrate.

Step 10: Dry the substrate.

4001: Solution tank

4003: The third pump

4005: Thermometer

4007: Drain pipe

4008: Controller

4009: Third Import

4013: heater

4015: second import

4017: first import

4019: The first pump

4021: Buffer slot

4023: second pump

4029: Needle valve

4030: Exhaust pipe

Claims (11)

A high-temperature chemical solution supply system for cleaning substrates, including: a solution tank containing high-temperature chemical solutions; a buffer tank, including a tank, an exhaust pipe and a needle valve, the tank containing the high-temperature chemical solution, and one end of the exhaust pipe Connect the tank body, the other end of the exhaust pipe is connected to the solution tank, the needle valve is installed on the exhaust pipe, and the needle valve is adjusted to achieve a flow rate so that the bubbles in the high temperature chemical solution are discharged from the buffer tank through the exhaust pipe; the first pump, The inlet of the first pump is connected to the solution tank, the outlet of the first pump is connected to the buffer tank; and the second pump, the inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate; The output pressure is adjusted so that the pressure range of the buffer tank is between 5psi-20psi. The liquid supply system according to claim 1, further comprising a third pump and a heater, the third pump is connected to the solution tank and the heater, and the heater is connected to the solution tank. The liquid supply system according to claim 1, further comprising a thermometer and a controller. The liquid supply system according to claim 1, wherein the solution tank has a first inlet for entering deionized water, a second inlet for entering the first chemical liquid, and a third inlet for entering the second chemical liquid . The liquid supply system according to claim 4, wherein the first chemical liquid is hydrogen peroxide and the second chemical liquid is ammonia. The liquid supply system according to claim 1, wherein the buffer tank further includes a liquid inlet pipe and a liquid outlet pipe, the liquid inlet pipe and the liquid outlet pipe are inserted near the bottom of the tank body, and the exhaust pipe is installed at the top of the buffer tank. The bubbles in the chemical solution rise and exit the buffer tank through the exhaust pipe. The liquid supply system according to claim 6, wherein the buffer tank further includes a bubble separator to prevent bubbles output from the liquid inlet pipe from entering the liquid outlet pipe. The liquid supply system according to claim 1, wherein the buffer tank further includes a liquid inlet pipe and a liquid outlet pipe, the liquid inlet pipe is inserted near the bottom of the tank body, the liquid outlet pipe is installed on the top of the buffer tank, and the exhaust pipe is installed on the top of the buffer tank. The top of the buffer tank. The liquid supply system according to claim 1, further comprising at least one second buffer tank and at least one fourth pump arranged between the outlet of the second pump and the cleaning cavity. The liquid supply system according to claim 1, wherein the outer surface of the solution tank is wrapped with a heat insulating material. A substrate cleaning device includes: a solution tank containing a high-temperature chemical solution; a buffer tank including a tank body, an exhaust pipe and a needle valve, the tank body contains the high-temperature chemical solution, one end of the exhaust pipe is connected to the tank body, and the exhaust pipe Connect the solution tank and needle at the other end The valve is installed on the exhaust pipe, and the air bubbles in the high temperature chemical solution are discharged from the buffer tank through the exhaust pipe by adjusting the needle valve to achieve a flow; the first pump, the inlet of the first pump is connected to the solution tank, and the outlet of the first pump is connected Buffer tank, where the output pressure of the first pump is adjusted so that the pressure range of the buffer tank is between 5psi-20psi; the second pump, the inlet of the second pump is connected to the buffer tank, and the outlet of the second pump is connected to the cleaning chamber for cleaning the substrate ；Substrate chuck, which carries the substrate; Rotation drive device, connects the substrate chuck and drives the substrate chuck to rotate; Nozzle, sprays high temperature chemical solution or deionized water on the surface of the substrate; Ultrasonic/Megasonic device, set in Near the substrate, there is a gap between the substrate and the ultrasonic/megasonic device; the vertical driver drives the ultrasonic/megasonic device up or down to change the gap between the substrate and the ultrasonic/megasonic device.

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