Quick drain rinsing tank of slot type cleaning apparatus and wafer cleaning method

Abstract

The application provides a quick-discharge rinsing tank of a tank cleaning device, which comprises a tank body, a first gas supply pipeline, a second gas supply pipeline, a bubbling device and a lower water supply pipeline, the bubbling device is connected with the first gas supply pipeline and the second gas supply pipeline, is used for processing small-molecule nitrogen gas introduced by the first gas supply pipeline into small-molecule nitrogen gas bubbles, and is used for processing conventional nitrogen gas introduced by the second gas supply pipeline into conventional nitrogen gas bubbles, and the small-molecule nitrogen gas bubbles will be broken under the impact of the conventional nitrogen gas bubbles; and the lower water supply pipeline is used for introducing deionized water into the tank body. The small-molecule nitrogen gas is broken, the cleaning effect of a wafer is improved, and the cleaning time is reduced.

Description

Technical Field

[0001] This invention relates to the field of wafer cleaning technology, and more particularly to a quick-drain rinsing tank for a tank-type cleaning device and a wafer cleaning method. Background Technology

[0002] With the development of the semiconductor industry, the key dimensions of device process technology are constantly shrinking, placing higher demands on the cleanliness of wafers in each processing step. Current wafer wet cleaning methods can be divided into three types: tank cleaning, rotary rinsing, and single-wafer cleaning. Among these, tank cleaning is widely used due to its high efficiency. After cleaning, chemical residues on the wafer must be removed, and each step of the wet cleaning chemical process is followed by deionized water rinsing. The QDR (Quick Dump Rinse) tank is a commonly used method in deionized water rinsing and is an indispensable part of tank cleaning equipment. It is mainly used to remove particulate impurities and residual chemicals from the wafer surface, making the wafer surface clean. However, to improve the cleaning effect, multiple cycles of nitrogen purging, evacuation, and water injection are often required, which is time-consuming and uses a large amount of water. Therefore, it is necessary to propose a quick-dump rinsing tank with excellent cleaning effect. Summary of the Invention

[0003] This invention provides a quick-drain rinsing tank for a trough-type cleaning device, which has a very good wafer cleaning effect.

[0004] In a first aspect, the present invention provides a quick-drain rinsing tank for a trough-type cleaning device, comprising:

[0005] Tank body;

[0006] The first gas supply line is used to introduce small molecule nitrogen into the tank.

[0007] The second gas supply line is used to introduce conventional nitrogen into the tank.

[0008] A bubbling device is located at the bottom of the tank and is connected to the first gas supply line and the second gas supply line. The bubbling device is used to process the introduced small molecule nitrogen gas into small molecule nitrogen bubbles and to process the introduced conventional nitrogen gas into conventional nitrogen bubbles.

[0009] A lower water supply pipe is installed at the bottom of the tank, and the lower water supply pipe is used to supply deionized water into the tank.

[0010] Optionally, the small molecule nitrogen gas has a molecular size of less than 80 nm.

[0011] Optionally, the outlet of the lower water supply pipeline is located on both sides of the bubbling device.

[0012] Optionally, the top of the tank is provided with an upper water supply pipe for spraying the wafers to be cleaned.

[0013] Optionally, the outlets of the upper water supply pipeline are located on both sides of the top to form a cross-spraying system.

[0014] Secondly, the present invention provides a wafer cleaning method based on a fast-drain rinsing tank of a tank-type cleaning equipment, comprising:

[0015] Step 1: Transfer the wafer to be cleaned into the quick-drain rinsing tank of the tank cleaning equipment;

[0016] Step 2: Pour deionized water into the tank from the bottom and continue for the first set time to perform overflow cleaning;

[0017] Step 3: Keep deionized water flowing in, and at the same time, introduce small molecule nitrogen gas into the bubbling device at the bottom of the tank for the second set time, so that the small molecule nitrogen gas bubbles formed after being processed by the bubbling device fill the tank.

[0018] Step 4: Keep deionized water and small molecule nitrogen flowing through, while simultaneously introducing conventional nitrogen into the bubbling device at the bottom of the tank for a third set time. This allows the conventional nitrogen bubbles formed after being processed by the bubbling device to impact the small molecule nitrogen bubbles, causing the small molecule nitrogen bubbles to rupture under the impact.

[0019] Step 5: Stop introducing deionized water, small molecule nitrogen and regular nitrogen from the bottom, spray deionized water from the top of the tank to be cleaned for the fourth set time, and drain the water quickly.

[0020] Step 6: Repeat steps 2-5 until the set number of times is met;

[0021] Step 7: Continue to introduce deionized water into the tank from the bottom for the fifth set time.

[0022] Optionally, the supply flow rate of the small molecule nitrogen is greater than 30 liters / minute, and the supply time is greater than 1 minute.

[0023] Optionally, the small molecule nitrogen gas has a molecular size of less than 80 nm.

[0024] The quick-drain rinsing tank and wafer cleaning method of the tank-type cleaning equipment provided by the present invention utilize conventional nitrogen gas to impact small molecule nitrogen gas, causing the small molecule nitrogen gas to break under the impact, thereby enhancing the cleaning effect of the wafer. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the quick-drain rinsing tank of a trough-type cleaning device provided in an embodiment of the present invention;

[0026] Figures 2-6 This is a schematic diagram of the corresponding steps of a wafer cleaning method provided in another embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of this disclosure.

[0028] This embodiment provides a quick-drain rinsing tank for a trough-type cleaning device. Figure 1 This is a schematic diagram of the quick-drain rinsing tank, used to illustrate the inventive points of this application. Figure 1 Some commonly used components have been omitted. For example... Figure 1 As shown, the rapid rinsing tank includes a tank body 11, with a bubbling device 12 located near the bottom of the tank body 11. The bubbling device 12 generally includes a flow equalization plate for forming uniform bubbles. The bubbling device 12 is connected to a first air supply line 13 and a second air supply line 14. The first air supply line 13 supplies small-molecule nitrogen gas into the tank, which can be generated using a small-molecule nitrogen generator. The second air supply line 14 supplies conventional nitrogen gas into the tank, which can be generated using a nitrogen source. The bubbling device 12 processes the introduced small-molecule nitrogen gas into small-molecule nitrogen bubbles and the introduced conventional nitrogen gas into conventional nitrogen bubbles.

[0029] In practical applications, small molecule nitrogen bubbles first fill the tank, and then conventional nitrogen bubbles enter the tank and impact the small molecule nitrogen bubbles inside. Under the impact of the conventional nitrogen bubbles, the small molecule nitrogen bubbles will break, producing a tiny scrubbing action on the wafer surface, which can maximize the wafer cleaning effect.

[0030] In addition, the quick-drain rinsing tank is generally equipped with two water supply lines. The inlet of the water supply line is connected to the deionized water supply source. One water supply line is located at the bottom of the tank, which can be called the lower water supply line 15. It has two outlets, located on both sides of the bubbling device 12. The lower water supply line 15 is used to introduce deionized water (DIW) into the tank from the bottom. After the deionized water fills the tank, it overflows from the top and all around the tank. The other water supply line is located at the top of the tank, which can be called the upper water supply line 16. It is used to spray the wafers to be cleaned. Generally, the upper water supply line 16 has outlets on the left and right sides of the top to form a cross spray.

[0031] Using the fast-drain rinsing tank provided in the above embodiments, another embodiment of the present invention provides a wafer cleaning method, which is performed according to the following steps:

[0032] Step 1: Reference Figure 2 The wafers to be cleaned are transferred into the quick-drain rinsing tank of the tank-type cleaning equipment. This step is usually performed by a robotic arm.

[0033] Step 2: Reference Figure 3 Under control, the water supply pipeline is opened, and deionized water is introduced into the tank from the bottom of the tank for a first set time, such as 30 seconds, to perform overflow cleaning. After the deionized water fills the tank, it overflows from the top and all sides of the tank.

[0034] Step 3: Reference Figure 4 Keep deionized water flowing in, and simultaneously control the first gas supply line to be open, so that small molecule nitrogen gas is introduced into the bubbling device at the bottom of the tank. The molecules of small molecule nitrogen gas are less than 80nm. Continue for a second set time, such as 40 seconds. After being processed by the bubbling device, the small molecule nitrogen gas forms small molecule nitrogen gas bubbles, which fill the tank.

[0035] Step 4: Reference Figure 5 Maintain the flow of deionized water and small molecule nitrogen, while controlling the second gas supply line to flow into the bubbling device at the bottom of the tank, and continue for a third set time, such as 60 seconds. After being processed by the bubbling device, the conventional nitrogen forms conventional nitrogen bubbles. The conventional nitrogen bubbles impact the small molecule nitrogen bubbles, causing them to rupture.

[0036] Step 5: Reference Figure 6 Close the lower water supply line, the first air supply line, and the second air supply line. Stop the flow of deionized water, small molecule nitrogen, and conventional nitrogen from the bottom. Control the upper water supply line to be open and spray deionized water from the top of the tank onto the wafer to be cleaned for a fourth set time, such as 20 seconds, and then drain the water quickly.

[0037] Step 6: Repeat steps 2-5 above until the set number of times is met, for example, repeat 1-2 times.

[0038] Step 7: Control the water supply line to open again, and introduce deionized water into the tank from the bottom of the tank for the fifth set time, such as 30 seconds, until the cleaning process ends.

[0039] After cleaning, the cleaned wafers are removed from the quick-drain rinsing tank, and then the next batch of wafers is cleaned.

[0040] During the cleaning process described above, the supply flow rates of small molecule nitrogen, conventional nitrogen, and deionized water can be adjusted as needed. For example, the supply flow rate of small molecule nitrogen can be designed to be greater than 30 liters per minute.

[0041] The wafer cleaning method provided in this embodiment first fills the tank with small molecule nitrogen bubbles, and then conventional nitrogen bubbles enter the tank. The conventional nitrogen bubbles impact the small molecule nitrogen bubbles, causing them to break and producing extremely small wiping motions on the wafer surface, which can enhance the wafer cleaning effect.

[0042] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A rapid rinsing tank for a trough-type cleaning device, characterized in that, The rapid flushing tank includes: The tank is used to hold the wafers to be cleaned; The first gas supply line is used to introduce small molecule nitrogen into the tank. The second gas supply line is used to introduce conventional nitrogen into the tank after the small molecule nitrogen bubbles formed by the small molecule nitrogen fill the tank. The conventional nitrogen bubbles formed by the conventional nitrogen impact the small molecule nitrogen bubbles, causing the small molecule nitrogen bubbles to break and generating a scrubbing action on the surface of the wafer to be cleaned. A bubbling device is located at the bottom of the tank and is connected to the first gas supply line and the second gas supply line. The bubbling device is used to process the introduced small molecule nitrogen gas into small molecule nitrogen bubbles and to process the introduced conventional nitrogen gas into conventional nitrogen bubbles. A lower water supply pipe is installed at the bottom of the tank, and the lower water supply pipe is used to supply deionized water into the tank.

2. The rapid flushing tank according to claim 1, characterized in that, The small molecule nitrogen gas has a molecular size of less than 80 nm.

3. The rapid flushing tank according to claim 1, characterized in that, The outlet of the lower water supply pipeline is located on both sides of the bubbling device.

4. The rapid flushing tank according to claim 1, characterized in that, The top of the tank is equipped with an upper water supply pipe for spraying the wafers to be cleaned.

5. The rapid flushing tank according to claim 4, characterized in that, The outlets of the upper water supply pipeline are located on both sides of the top to form a cross-spray system.

6. A wafer cleaning method based on a rapid rinsing tank of a tank-type cleaning equipment, characterized in that, The method includes: Step 1: Transfer the wafer to be cleaned into the quick-drain rinsing tank of the tank cleaning equipment; Step 2: Pour deionized water into the tank from the bottom and continue for the first set time to perform overflow cleaning; Step 3: Keep deionized water flowing in, and at the same time, introduce small molecule nitrogen gas into the bubbling device at the bottom of the tank for the second set time, so that the small molecule nitrogen gas bubbles formed after being processed by the bubbling device fill the tank. Step 4: Keep deionized water and small molecule nitrogen flowing through, while simultaneously introducing conventional nitrogen into the bubbling device at the bottom of the tank for a third set time. This allows the conventional nitrogen bubbles formed after being processed by the bubbling device to impact the small molecule nitrogen bubbles. The small molecule nitrogen bubbles break under the impact, resulting in a scrubbing action on the surface of the wafer to be cleaned. Step 5: Stop introducing deionized water, small molecule nitrogen and regular nitrogen from the bottom, spray deionized water from the top of the tank to be cleaned for the fourth set time, and drain the water quickly. Step 6: Repeat steps 2-5 until the set number of times is met; Step 7: Continue to introduce deionized water into the tank from the bottom for the fifth set time.

7. The method according to claim 6, characterized in that, The supply flow rate of the small molecule nitrogen gas is greater than 30 liters / minute, and the supply time is greater than 1 minute.

8. The method according to claim 6, characterized in that, The small molecule nitrogen gas has a molecular size of less than 80 nm.

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