RCA alkaline cleaning tank for removing RCA basket marks

Abstract

This utility model relates to the field of alkaline washing tank technology, and in particular to an RCA alkaline washing tank for removing RCA basket marks. It includes an outer tank body, an inner tank body, a nitrogen bubbling pipe, a flow equalization component, and a circulating heating component. The inner tank body is arranged inside the outer tank body, forming an inner cavity. The flow equalization component is arranged above the nitrogen bubbling pipe. The flow equalization component includes a main flow equalization plate and an auxiliary flow equalization plate. The main flow equalization plate is fixedly connected to the inner tank body. The main flow equalization plate has several flow equalization holes. The auxiliary flow equalization plate is located within the flow equalization holes and is fixedly connected to the main flow equalization plate. The auxiliary flow equalization plate has a first turbulence hole at its center and two second turbulence holes. The first turbulence hole is located between the second turbulence holes. Through the multi-stage flow equalization and turbulence structure of the main flow equalization plate, auxiliary flow equalization plate, and specially designed flow channels, the nitrogen bubbles and hot fluid from the bottom are dispersed and redistributed, forming a uniform and stable upward flow field in the basket placement area.

Description

Technical Field

[0001] This utility model relates to the field of alkaline washing tank technology, and in particular to an RCA alkaline washing tank for removing RCA basket prints. Background Technology

[0002] In the manufacturing process of semiconductor and photovoltaic silicon wafers, the RCA standard cleaning process is a crucial step, used to remove organic contaminants, metal ions, and particulate matter from the surface of the silicon wafers. In this process, silicon wafers are typically placed in a specially designed basket and then immersed in a chemical cleaning tank for treatment. However, traditional RCA alkaline cleaning tanks have some technical drawbacks in practical applications. First, the flow of the chemical solution within the tank is often uneven, easily forming laminar flow or dead zones on the basket and silicon wafer surface, resulting in uneven local concentration and temperature. This unevenness leads to poor cleaning at the contact points between the basket and the silicon wafer, leaving a mark known as a "basket mark" on the silicon wafer, severely affecting product yield. Second, while traditional bubbling methods (such as air bubbling) can provide some stirring, the bubbles are of varying sizes and unevenly distributed, resulting in limited disturbance and potentially introducing new contaminants or causing oxidation of the chemical solution. Utility Model Content

[0003] The technical problem to be solved by this utility model is: in order to overcome the problem that although the traditional bubbling method (such as air bubbling) in the prior art can play a certain stirring role, the bubbles are of different sizes and unevenly distributed, the disturbance effect is limited, and new pollutants may be introduced or chemical solutions may be oxidized, an RCA alkaline washing tank for removing RCA basket marks is provided.

[0004] The technical solution adopted by this utility model to solve its technical problem is: an RCA alkaline washing tank for removing RCA basket prints, comprising an outer tank body, an inner tank body, a nitrogen bubbling pipe, a flow equalization component, and a circulating heating component. The inner tank body is arranged inside the outer tank body, forming an inner cavity within the inner tank body. An outer cavity is formed between the outer tank body and the inner tank body. The upper part of the outer cavity body is connected to the upper part of the inner cavity body. The nitrogen bubbling pipe is arranged at the bottom of the inner cavity body of the inner tank body and is used to provide nitrogen for cleaning the basket prints. The input end of the circulating heating component is connected to the outer cavity, and the output end of the circulating heating component is connected to the inner cavity. The circulating heating component is used to provide heat fluid to the inner cavity. The flow equalization assembly is arranged above the nitrogen bubbling tube. The flow equalization assembly includes a main flow equalization plate and an auxiliary flow equalization plate. The main flow equalization plate is fixedly connected to the inner tank. The main flow equalization plate has several flow equalization holes. The auxiliary flow equalization plate is located inside the flow equalization holes and is fixedly connected to the main flow equalization plate. The auxiliary flow equalization plate has a first turbulence hole in its center and two second turbulence holes. The first turbulence hole is located between the second turbulence holes. Through the multi-stage flow equalization and turbulence structure of the main flow equalization plate, auxiliary flow equalization plate, and specially designed flow channel, the nitrogen bubbles and hot fluid from the bottom are dispersed and redistributed to form a uniform and stable upward flow field in the basket placement area, avoiding dead zones or insufficient turbulence.

[0005] To address the issue that a simple flow equalization orifice structure may not effectively break up bubbles, mix fluids, or even generate new unstable flow patterns when fluid passes through, the flow equalization orifice is further improved by including a confluence section, a transition section, and a diffusion section arranged sequentially from bottom to top. The confluence section has an inward contraction structure from bottom to top, the transition section has a columnar structure, and the diffusion section has an outward expansion structure from bottom to top.

[0006] To address the issue of improper installation of the flow equalization auxiliary plate affecting the overall flow equalization effect, the design further includes placing the flow equalization auxiliary plate within the transition section.

[0007] To address the issue that the fluid may re-converge or generate large eddies due to the reduced flow velocity in the diffuser section, leading to a non-uniform flow field above, a further feature is included: a turbulence block is arranged in the middle of the diffuser section, located above the first turbulence hole.

[0008] To address the issue that if the spoiler is too small, the spoiling effect will be insufficient, while if it is too large, it will cause excessive resistance and generate severe turbulence, the width of the spoiler is further specified to be between one-third and one-half the width of the transition section.

[0009] To address the issue of flower baskets being placed arbitrarily, potentially deviating from the optimal cleaning area and affecting the maximization of flow equalization, a further feature is included: a bracket for placing flower baskets is installed on the top surface of the flow equalization mainboard; the bracket and the flow equalization hole correspond one-to-one, and the bracket and the flow equalization hole are arranged coaxially.

[0010] To address the limited effectiveness of chemical cleaning and physical bubbling in removing certain stubborn, particularly submicron-sized particulate contaminants, the system further includes an ultrasonic generator mounted on the outer wall of the outer tank. This ultrasonic generator is used to vibrate the fluid within both the outer and inner cavities.

[0011] To address the issue of how to efficiently and stably heat and circulate the liquid medicine in the tank, thereby avoiding local temperature differences and ensuring the chemical reaction rate, a circulating heating component is further included, comprising a heater and a circulating pump. The input end of the heater is connected to the outer cavity, the output end of the heater is connected to the input end of the circulating pump, and the output end of the circulating pump is connected to the inner cavity.

[0012] The beneficial effects of this utility model are: The RCA alkaline washing tank for removing RCA basket marks provided by this utility model, through the multi-stage flow equalization and turbulence structure of the flow equalization main plate, the flow equalization auxiliary plate, and the special flow channel design, disperses and redistributes the nitrogen bubbles and hot fluid from the bottom, forming a uniform and stable upward flow field in the basket placement area, avoiding the flow dead zone or insufficient turbulence. Attached Figure Description

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a utility model Figure 1 Enlarged structural diagram at point A in the middle.

[0015] In the diagram: 1. Outer tank, 11. Outer cavity, 2. Inner tank, 21. Inner cavity, 3. Nitrogen bubbling tube, 4. Flow equalization assembly, 41. Flow equalization main board, 411. Flow equalization hole, 4111. Merging section, 4112. Transition section, 4113. Diffusion section, 42. Flow equalization auxiliary plate, 421. First turbulence hole, 422. Second turbulence hole, 43. Turbulence block, 5. Circulation heating assembly, 51. Heater, 52. Circulation pump, 6. Support, 7. Ultrasonic generator. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0017] like Figure 1 This is a schematic diagram of the structure of this utility model. An RCA alkaline washing tank for removing RCA basket prints includes an outer tank 1, an inner tank 2, a nitrogen bubbling pipe 3, a flow equalization component 4, and a circulating heating component 5. The inner tank 2 is arranged inside the outer tank 1, forming an inner cavity 21. An outer cavity 11 is formed between the outer tank 1 and the inner tank 2. The upper part of the outer cavity 11 is connected to the upper part of the inner cavity 21. The nitrogen bubbling pipe 3 is arranged at the bottom of the inner cavity 21 of the inner tank 2 and is used to provide nitrogen for cleaning the basket prints. The input end of the circulating heating component 5 is connected to the outer cavity 11, and the output end of the circulating heating component 5 is connected to the inner cavity 21. The circulating heating component 5 is used to provide heat fluid to the inner cavity 21. The flow equalization assembly 4 is arranged above the nitrogen bubble tube 3. The flow equalization assembly 4 includes a flow equalization main plate 41 and a flow equalization auxiliary plate 42. The flow equalization main plate 41 is fixedly connected to the inner tank 2. The flow equalization main plate 41 has several flow equalization holes 411. The flow equalization auxiliary plate 42 is located inside the flow equalization holes 411 and is fixedly connected to the flow equalization main plate 41. The flow equalization auxiliary plate 42 has a first turbulence hole 421 in the center and two second turbulence holes 422. The first turbulence hole 421 is located between the second turbulence holes 422. Through the multi-stage flow equalization and turbulence structure of the flow equalization main plate 41, the flow equalization auxiliary plate 42, and the specially designed flow channel, the nitrogen bubbles and hot fluid from the bottom are dispersed and redistributed to form a uniform and stable upward flow field in the basket placement area, avoiding dead zones or insufficient turbulence.

[0018] like Figure 1 , 2 As shown, the flow equalization orifice 411 includes a converging section 4111, a transition section 4112, and a diffusion section 4113 arranged sequentially from bottom to top. The converging section 4111 has a converging structure from bottom to top, the transition section 4112 has a columnar structure, and the diffusion section 4113 has an expanding structure from bottom to top. The three-section orifice design can first gather and accelerate the fluid, then conduct preliminary turbulence in the stable section, and finally reduce the flow velocity and further mix it through diffusion, thus achieving a more stable and uniform fluid output.

[0019] like Figure 1 , 2 As shown, the flow equalization auxiliary plate 42 is located in the transition section 4112. Fixing the flow equalization auxiliary plate 42 in the transition section with stable flow velocity and constant cross-sectional area makes the turbulence effect controllable and consistent, ensuring the uniformity of the outflow from each flow channel.

[0020] like Figure 1 , 2 As shown, a turbulence block 43 is arranged in the middle of the diffuser section 4113. The turbulence block 43 is located above the first turbulence hole 421. The turbulence block 43 is set in the middle of the diffuser section 4113 to regulate the fluid that is about to flow out, break up any bubbles or fluid clusters that may aggregate, and ensure that the fluid flowing out of the flow equalization hole achieves the best uniformity.

[0021] like Figure 1 , 2 As shown, the width of the turbulence block 43 is between one-third and one-half the width of the transition section 4112. Limiting the width of the turbulence block 43 to 1 / 3 to 1 / 2 of the width of the transition section 4112 can achieve the best balance between effective turbulence and maintaining a stable flow field, ensuring the flow uniformity effect while avoiding excessive energy loss and potential impact on the silicon wafer.

[0022] like Figure 1 , 2As shown, a bracket 6 for placing flower baskets is installed on the top surface of the current equalization main board 41. The bracket 6 and the current equalization hole 411 correspond one-to-one, and the bracket 6 and the current equalization hole 411 are arranged coaxially. By arranging the bracket 6 and the current equalization hole 411 coaxially, each flower basket can be accurately positioned at the center of the most uniform fluid formed by the corresponding current equalization hole, thereby ensuring that all silicon wafers obtain a consistent and optimal cleaning effect.

[0023] like Figure 1 As shown, an ultrasonic generator 7 is installed on the outer wall of the outer tank 1. The ultrasonic generator 7 is used to vibrate the fluid in the outer cavity 11 and the inner cavity 21 to introduce ultrasonic cleaning. Through high-frequency mechanical vibration, a cavitation effect is generated in the liquid, which can powerfully shake off the tiny particles attached to the silicon wafer surface. It complements chemical cleaning and bubbling flow equalization, significantly improving the overall decontamination capability of the equipment.

[0024] like Figure 1 As shown, the circulating heating assembly 5 includes a heater 51 and a circulating pump 52. The input end of the heater 51 is connected to the outer cavity 11, the output end of the heater 51 is connected to the input end of the circulating pump 52, and the output end of the circulating pump 52 is connected to the inner cavity 21. This realizes continuous mixing and temperature control of the liquid in the tank, effectively eliminates temperature stratification, and ensures the stability of the chemical environment throughout the cleaning process.

[0025] Working process: A predetermined amount of RCA alkaline cleaning solution is injected into the inner cavity 21 and the outer cavity 11. The circulating heating component 5 and the nitrogen bubbling tube 3 are turned on. The circulating pump 52 draws out the relatively cool liquid from the outer cavity 11 and sends it to the heater 51 for heating. The heated liquid is pumped into the bottom of the inner cavity 21. Nitrogen is released from the nitrogen bubbling tube 3 at the bottom, forming bubbles that move upward. At the same time, the hot fluid injected from the circulating heating component 5 also flows upward. This gas-liquid mixture first impacts the flow equalization board 41 and is distributed to each flow equalization orifice 411. In the flow equalization orifice 411, the fluid passes through the converging confluence section 4. The flow accelerates to the transition section 4112, where the flow equalization plate 42 and its first and second turbulence holes 421 and 422 perform initial cutting and turbulence on the fluid. Subsequently, the fluid enters the diffusion section 4113, where the flow rate decreases, but encounters the upper turbulence block 43, generating a second turbulence that further breaks up and mixes the bubbles. After multiple stages of flow equalization and turbulence, the fine and evenly distributed bubbles and hot fluid flow smoothly upwards through the basket placed on the support 6, providing a uniform, gentle, and efficient cleaning of the silicon wafers within the basket. The cleaning solution overflows from the upper part of the inner cavity 21 to the outer cavity 11, completing one cycle. The entire process continues until the cleaning procedure ends. During this period, the ultrasonic generator 7 can be selectively activated to enhance the ability to remove particulate contaminants.

[0026] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. An RCA alkaline cleaning tank for removing RCA basket marks, characterized by, The system includes an outer tank (1), an inner tank (2), a nitrogen bubbling pipe (3), a flow equalization component (4), and a circulating heating component (5). The inner tank (2) is arranged inside the outer tank (1), forming an inner cavity (21). An outer cavity (11) is formed between the outer tank (1) and the inner tank (2). The upper part of the outer cavity (11) is connected to the upper part of the inner cavity (21). The nitrogen bubbling pipe (3) is arranged at the bottom of the inner cavity (21) of the inner tank (2). The nitrogen bubbling pipe (3) is used to provide nitrogen for cleaning the flower basket. The input end of the circulating heating component (5) is connected to the outer cavity (11), and the output end of the circulating heating component (5) is connected to the inner cavity (21). The circulating heating component (5) is used to provide heat fluid to the inner cavity (21). The flow equalization assembly (4) is arranged above the nitrogen bubbling tube (3). The flow equalization assembly (4) includes a flow equalization main plate (41) and a flow equalization auxiliary plate (42). The flow equalization main plate (41) is fixedly connected to the inner tank (2). The flow equalization main plate (41) has a plurality of flow equalization holes (411). The flow equalization auxiliary plate (42) is located inside the flow equalization holes (411) and is fixedly connected to the flow equalization main plate (41). The flow equalization auxiliary plate (42) has a first turbulence hole (421) in the center and two second turbulence holes (422) in the flow equalization auxiliary plate (42). The first turbulence hole (421) is located between the second turbulence holes (422).

2. The RCA base wash tank to remove RCA basket marks as claimed in claim 1, wherein: The flow equalization orifice (411) includes a converging section (4111), a transition section (4112), and a diffusion section (4113) arranged sequentially from bottom to top. The converging section (4111) has a structure that contracts inward from bottom to top, the transition section (4112) has a columnar structure, and the diffusion section (4113) has a structure that expands outward from bottom to top.

3. The RCA base wash tank to remove RCA basket marks as claimed in claim 2, wherein: The flow equalization auxiliary plate (42) is located within the transition section (4112).

4. The RCA base wash tank to remove RCA basket marks as claimed in claim 2, wherein: A turbulence block (43) is arranged in the middle of the diffuser section (4113), and the turbulence block (43) is located above the first turbulence hole (421).

5. The RCA alkaline washing tank for removing RCA basket prints as described in claim 4, characterized in that: The width of the turbulence block (43) is between one-third and one-half the width of the transition section (4112).

6. The RCA base wash tank to remove RCA basket marks as claimed in claim 1, wherein: The top surface of the flow equalization main board (41) is equipped with a bracket (6) for placing the flower basket. The bracket (6) and the flow equalization hole (411) correspond one-to-one, and the bracket (6) and the flow equalization hole (411) are arranged coaxially.

7. The RCA base wash tank to remove RCA basket marks as claimed in claim 1, wherein: An ultrasonic generator (7) is installed on the outer wall of the outer tank (1), and the ultrasonic generator (7) is used to vibrate the fluid in the outer cavity (11) and the inner cavity (21).

8. The RCA base wash tank to remove RCA basket marks as claimed in claim 1, wherein: The circulating heating assembly (5) includes a heater (51) and a circulating pump (52). The input end of the heater (51) is connected to the outer cavity (11), the output end of the heater (51) is connected to the input end of the circulating pump (52), and the output end of the circulating pump (52) is connected to the inner cavity (21).

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