A wafer silicon chip DHF cleaning machine based on RCA cleaning method and a cleaning method thereof

Abstract

The application relates to the technical field of wafer silicon chip cleaning, in particular to a wafer silicon chip DHF cleaning machine based on an RCA cleaning method and a cleaning method thereof, wherein the wafer silicon chip DHF cleaning machine based on the RCA cleaning method comprises a cleaning tank installed in a cleaning cavity in a cleaning cabinet, a mounting plate is further arranged in the cleaning cavity, the mounting plate is connected with a lifting piece arranged in the cleaning cavity, the lifting piece can drive the mounting plate to lift relative to the cleaning cabinet; a brush roller is arranged on the mounting plate, the brush roller is connected with a longitudinal moving assembly arranged on the mounting plate, the longitudinal moving assembly can drive the brush roller to slide along the width direction of the mounting plate; a transverse moving assembly is further arranged in the mounting plate, the transverse moving assembly can drive the brush roller to slide along the length direction of the mounting plate; the inside wall of the cleaning tank can be brushed and washed by gradually cooperating with the components and rotating the brush roller, residual liquid adhered to the inside wall can be removed, and the residual liquid and new liquid are prevented from being combined after liquid replacement, so that the concentration of the cleaning agent is prevented from changing.

Description

Technical Field

[0001] This invention relates to the field of wafer cleaning technology, specifically a wafer DHF cleaning machine and its cleaning method based on the RCA cleaning method. Background Technology

[0002] RCA cleaning is a standard wet cleaning process for silicon wafers in the semiconductor industry. Its core function is to remove contaminants such as organic matter, particles, and metal ions from the wafer surface, ensuring the yield and device performance of subsequent chip manufacturing processes.

[0003] The DHF cleaning process is mainly used to remove the natural oxide layer on the surface of the wafer. Currently, existing cleaning machines are usually equipped with a cleaning tank for holding the cleaning solution. The bottom of the cleaning tank is equipped with a drain hole. After cleaning a batch of wafers, the solution needs to be drained and replaced with new cleaning solution for the next batch.

[0004] During solution replacement, gravity is typically used to allow the old solution to drain from the drain hole at the bottom of the cleaning tank. At this time, the inner wall of the cleaning tank often retains waste solution from the previous batch. In existing technologies, fixed-position nozzles are typically used to spray and rinse the tank walls to clean them. However, the spray angle and range of these fixed-position nozzles are limited. The four right-angle corners of the inner wall, as well as the edges of the tank opening and bottom, are often outside the jet or in blind spots, easily creating cleaning dead zones and making it difficult to completely remove residual solution. If the tank walls are not thoroughly cleaned, the residual old solution will mix with the subsequently injected new solution, causing the concentration of critical solutions such as DHF to drift. This affects the removal rate and uniformity of the oxide layer on the wafer surface, ultimately reducing product yield. Summary of the Invention

[0005] The purpose of this invention is to provide a wafer silicon wafer DHF cleaning machine and cleaning method based on RCA cleaning method, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A wafer silicon wafer DHF cleaning machine based on RCA cleaning method includes a main frame unit, an FFU purification unit, a chemical solution unit, an acid pickling tank unit, and a wafer transfer system; the main frame unit includes a cleaning cabinet, and the FFU purification unit is disposed inside the cleaning cabinet at the top.

[0008] The pickling tank unit includes a cleaning tank installed inside a cleaning chamber within a cleaning cabinet. The cleaning chamber is also provided with an installation plate, which is connected to a lifting component installed in the cleaning chamber. The lifting component can drive the installation plate to move up and down relative to the cleaning cabinet.

[0009] A brush roller is provided on the mounting plate, and the brush roller is connected to a longitudinal moving component provided on the mounting plate. The longitudinal moving component can drive the brush roller to slide along the width direction of the mounting plate.

[0010] The mounting plate is also provided with a lateral moving component, which can drive the brush roller to slide along the length direction of the mounting plate.

[0011] The wafer silicon wafer DHF cleaning machine based on the RCA cleaning method as described above: the lifting component includes a vertical linear guide shaft installed on the inner wall of the cleaning chamber, and the vertical linear guide shaft is connected to the mounting plate.

[0012] As described above, the wafer silicon wafer DHF cleaning machine based on RCA cleaning method: the longitudinal moving component includes a longitudinal driving component and a limiting component. The limiting component includes plug-in cylinders symmetrically arranged along the length direction of the mounting plate. Each plug-in cylinder is slidably provided with a sliding plate. A moving rail is provided between the two sets of sliding plates. The brush roller is rotatably installed in the moving rail.

[0013] The wafer silicon wafer DHF cleaning machine based on the RCA cleaning method described above: the longitudinal drive component includes a longitudinal cylinder arranged along the width direction of the mounting plate, and the telescopic end of the longitudinal cylinder is connected to the moving rail.

[0014] As described above, the wafer silicon wafer DHF cleaning machine based on RCA cleaning method includes a lateral movement component and a mounting box. The lateral movement component includes a lateral cylinder arranged along the length direction of the mounting plate. The telescopic end of the lateral cylinder is slidably arranged in a slide rail, which is mounted on the mounting box. The brush roller is rotatably mounted in the mounting box and connected to a rotating structure arranged in the mounting box.

[0015] The wafer silicon wafer DHF cleaning machine based on the RCA cleaning method as described above: the rotating structure includes a motor mounted on the mounting box, the output shaft of the motor extending into the mounting box and connected to the brush roller via a chain.

[0016] As described above, the wafer silicon wafer DHF cleaning machine based on the RCA cleaning method has the following features: a limiting ring is provided inside the mounting plate, the outline of the limiting ring is the same as the outline of the inner wall of the cleaning tank, and the brush shaft of the brush roller contacts the limiting ring.

[0017] A cleaning method for a silicon wafer DHF cleaning machine is also proposed, characterized by employing a silicon wafer DHF cleaning machine based on the RCA cleaning method as described above, comprising the following steps:

[0018] Step 1: After the silicon wafer cleaning is completed, waste liquid will remain on the side walls of the cleaning tank when the solution is changed. After the silicon wafer is removed from the cleaning tank, the vertical linear guide shaft is driven to lower the mounting plate so that the brush roller is inserted into the cleaning tank and contacts the inner wall of the cleaning tank.

[0019] Step 2: Start the motor, and the brush rollers will continue to rotate in the same direction. Then, the longitudinal cylinder will retract and pull the moving rail to slide along the width of the cleaning tank until it reaches the end of its stroke. Then the longitudinal cylinder will stop and the transverse cylinder will move.

[0020] Step 3: The horizontal cylinder retracts and pulls the slide rail along the length of the cleaning tank until it reaches the end of its stroke. Then the horizontal cylinder stops, and the vertical cylinder resets, pushing the moving rail back along the width of the cleaning tank.

[0021] Step 4: After the longitudinal cylinder resets, the transverse cylinder resets, pushing the slide rail to slide along the length of the cleaning tank until the transverse cylinder stops moving. Then the brush roller returns to its initial position and moves around the inner wall of the cleaning tank once. During this process, the continuously rotating brush roller scrubs the inner wall of the cleaning tank, cleaning the residual liquid remaining on the inner wall of the cleaning tank.

[0022] Step 5: After cleaning is completed, the vertical linear guide shaft pulls the mounting plate up to reset.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] By setting up longitudinal and transverse moving components, and utilizing their cooperation, the brush roller can be driven to move along the width, length, width, and length of the limiting ring, thereby sequentially brushing the inner wall of the cleaning tank; compared with the traditional fixed-position spraying method, the cleaning effect is higher, and corners can be cleaned better.

[0025] Furthermore, the hollow brush roller is connected to the water injection pipe, and pure water is introduced into it while it rotates and brushes. The flowing pure water can carry away the chemical residues brushed off in time while the brush roller is brushing, preventing the residues from re-adhering to the tank wall and avoiding cross-contamination between the old liquid and the new liquid when cleaning the tank wall during the liquid change stage. This ensures the accuracy of the concentration of key chemicals such as DHF, thereby improving the stability of the oxide layer removal rate on the wafer surface.

[0026] By using the interlocking sleeve and the sliding plate, the displacement of the brush roller along the length direction is restricted. At the same time, a limiting ring that matches the contour of the cleaning tank is set to constrain the brush shaft of the brush roller. Under the combined action of the two, the radial runout and lateral sway of the brush roller during high-speed rotation and reciprocating movement can be reduced, so that the bristles are tightly attached to the tank wall and the cleaning force is uniform. Attached Figure Description

[0027] Figure 1This is a schematic diagram of the structure of a DHF cleaning machine for silicon wafers based on the RCA cleaning method;

[0028] Figure 2 This is a schematic diagram of the internal structure of the cleaning chamber in a DHF cleaning machine for silicon wafers based on the RCA cleaning method;

[0029] Figure 3 This is a schematic diagram of the structure of the brush roller in the DHF cleaning machine for silicon wafers based on the RCA cleaning method, in conjunction with the lifting component, the lateral moving component, and the longitudinal moving component.

[0030] Figure 4 This is a schematic diagram of the limiting ring structure in a DHF cleaning machine for silicon wafers based on the RCA cleaning method;

[0031] Figure 5 This is a schematic diagram of the structure of the brush roller, the transverse moving parts, and the longitudinal moving parts in the DHF cleaning machine for silicon wafers based on the RCA cleaning method.

[0032] Figure 6 This is a schematic diagram of the rotating structure inside the mounting box in a DHF cleaning machine for silicon wafers based on the RCA cleaning method;

[0033] Figure 7 This is a schematic diagram of the limiting component in a DHF cleaning machine for silicon wafers based on the RCA cleaning method;

[0034] Figure 8 This is a schematic diagram of the lateral movement component in a DHF cleaning machine for silicon wafers based on the RCA cleaning method.

[0035] In the diagram: 1. Cleaning cabinet; 101. Cleaning chamber; 2. Cleaning tank; 3. Vertical linear guide shaft; 4. Mounting plate; 5. Limiting ring; 6. Brush roller; 7. Horizontal cylinder; 8. Longitudinal cylinder; 9. Connecting cylinder; 10. Slide rail; 11. Mounting box; 12. Chain; 13. Moving rail; 1301. Slide plate. Detailed Implementation

[0036] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0037] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0038] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, and elements well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0039] Please see Figures 1-8 In this embodiment of the invention, a wafer silicon wafer DHF cleaning machine based on RCA cleaning method includes a main frame unit, an FFU purification unit, a chemical solution unit, and an acid pickling tank unit; the main frame unit includes a cleaning cabinet 1, and the FFU purification unit is disposed inside the cleaning cabinet 1 at the top.

[0040] The main frame unit adopts a steel frame welded corrosion-resistant coating structure to ensure a clean internal environment and adapt to highly corrosive working conditions such as hydrofluoric acid; the chemical solution unit includes a DHF solution storage, proportioning, and delivery subsystem, equipped with online concentration and temperature sensors, which can accurately control the parameters for diluting hydrofluoric acid and support closed-loop filtration and regeneration of chemical solutions.

[0041] The wafer silicon wafer DHF cleaning machine based on the RCA cleaning method also includes a wafer transport system equipped with a dedicated robotic arm with both electrical and mechanical limits for precise positioning and handling of wafers, supporting batch or single-wafer independent processing.

[0042] In addition, the FFU purification unit is one of the core units for constructing the clean environment of the wafer silicon wafer DHF cleaning machine. It includes a fan, a filter, and an electrical control module. The filter is located at the front end of the fan, and the electrical control module communicates with the fan through a frequency converter to realize zoned airflow adjustment. The fan draws in air from the top of the unit, which passes through a pre-filter and a high-efficiency filter, and finally delivers the clean air vertically downwards at a uniform wind speed of 0.45m / s±20%, forming a stable laminar airflow and avoiding airflow dead zones and secondary pollution in the clean area.

[0043] The pickling tank unit includes: a cleaning tank 2 installed in a cleaning chamber 101 inside the cleaning cabinet 1; a mounting plate 4 is also provided in the cleaning chamber 101; the mounting plate 4 is connected to a lifting component provided in the cleaning chamber 101; the lifting component can drive the mounting plate 4 to move up and down relative to the cleaning cabinet 1.

[0044] Preferably, the cleaning cabinet 1 is a fully enclosed corrosion-resistant cabinet, which is welded and formed by PP, PVDF and other materials resistant to hydrofluoric acid corrosion. It is equipped with a tempered glass window with acid mist extraction function, which can completely isolate HF acid mist leakage and ensure the safety of workshop operation. The cleaning cabinet 1 is also equipped with an automatic chemical solution control system.

[0045] The automatic cleaning solution control system is connected to the cleaning tank 2 via an inlet pipe, enabling precise dispensing of DHF cleaning solution of any concentration ratio. This solution then enters the cleaning tank 2 through the inlet pipe to clean the silicon wafers.

[0046] The lifting component includes a vertical linear guide shaft 3 installed on the inner wall of the cleaning chamber 101, and the vertical linear guide shaft 3 is connected to the mounting plate 4;

[0047] Specifically, such as Figure 2 , Figure 3 As shown, the vertical linear guide shaft 3 can drive the mounting plate 4 to move up and down in the vertical direction, so that the mounting plate 4 can switch between two states: away from or near the cleaning tank 2. When the mounting plate 4 is away from the cleaning tank 2, it is convenient for the operator to put in or take out the silicon wafer. When the mounting plate 4 is near the cleaning tank 2, the brush roller 6 set on the mounting plate 4 can clean the cleaning tank 2.

[0048] Further, please refer to Figures 4-8 The mounting plate 4 is provided with a brush roller 6, which is connected to a longitudinal moving component provided on the mounting plate 4. The longitudinal moving component can drive the brush roller 6 to slide along the width direction of the mounting plate 4.

[0049] The longitudinal moving component includes a longitudinal driving component and a limiting component. The limiting component includes plug-in cylinders 9 symmetrically arranged along the length direction of the mounting plate 4. Each plug-in cylinder 9 is slidably provided with a sliding plate 1301. A moving rail 13 is provided between the two sets of sliding plates 1301. The brush roller 6 is rotatably installed in the moving rail 13.

[0050] The longitudinal drive component includes a longitudinal cylinder 8 arranged along the width direction of the mounting plate 4, and the telescopic end of the longitudinal cylinder 8 is connected to the moving rail 13.

[0051] In detail, the cooperation between the plug-in cylinder 9 and the slide plate 1301 can restrict the brush roller 6 along the length direction of the cleaning tank 2, reduce the left and right shaking phenomenon that occurs when the longitudinal cylinder 8 drives the brush roller 6 to move along the width direction of the cleaning tank 2, thereby improving the movement stability of the brush roller 6.

[0052] Furthermore, the mounting plate 4 is also provided with a lateral moving component, which can drive the brush roller 6 to slide along the length direction of the mounting plate 4.

[0053] The lateral movement assembly includes a lateral drive component and a mounting box 11. The lateral drive component includes a lateral cylinder 7 arranged along the length of the mounting plate 4. The telescopic end of the lateral cylinder 7 is slidably arranged in a slide rail 10. The slide rail 10 is mounted on the mounting box 11. The brush roller 6 is rotatably mounted in the mounting box 11 and connected to a rotating structure arranged in the mounting box 11.

[0054] The rotating structure includes a motor mounted on the mounting box 11, the output shaft of the motor extending into the mounting box 11 and connected to the brush roller 6 via a chain 12;

[0055] A limiting ring 5 is provided inside the mounting plate 4. The outline of the limiting ring 5 is the same as the outline of the inner wall of the cleaning tank 2. The brush shaft of the brush roller 6 contacts the limiting ring 5. Under the restriction of the limiting ring 5 and the moving rail 13, the probability of the brush roller 6 jumping in the radial direction is reduced.

[0056] In combination with the above, in the initial state, the brush roller 6 is located at the end of the stroke of the moving rail 13. At this time, the brush roller is placed at the intersection of one set of long and wide sides of the limiting ring 5, and the mounting plate 4 is away from the cleaning tank 2.

[0057] After the silicon wafer cleaning is completed, the vertical linear guide shaft 3 drives the mounting plate 4 to descend until the mounting plate 4 reaches the preset position. Then, the vertical linear guide shaft 3 stops moving, the motor enters the working state, and drives the brush roller 6 to rotate continuously in the same direction. Then, the longitudinal cylinder 8 enters the working state and pulls the moving rail 13 to move along the width direction of the limiting ring 5. The brushes of the rotating brush roller 6 are used to brush one of the wide inner walls of the cleaning tank 2. During this process, the transverse cylinder 7 slides in the slide rail 10 until the longitudinal cylinder 8 moves to the end of its stroke. The brush roller 6 comes to the limiting ring 5 (i.e., the corner of the cleaning tank 2), and the longitudinal cylinder 8 stops moving.

[0058] Subsequently, the transverse cylinder 7 enters the working state, pulling the slide rail 10 and the mounting box 11 to slide along the moving rail 13 until the transverse cylinder 7 moves to the end of the stroke. The brush roller 6 moves along the moving rail 13 to the end of the stroke and is placed at another inflection point of the cleaning tank 2. During this process, the brush roller 6 brushes one of the long side inner walls of the cleaning tank 2.

[0059] Immediately afterwards, the transverse cylinder 7 stops moving, and the longitudinal cylinder 8 enters the reset working state, pushing the moving rail 13 to reset, so that the brush roller 6 can brush the inner wall of the other wide side of the cleaning tank 2.

[0060] After the moving rail 13 returns to its initial position, the longitudinal cylinder 8 stops moving. Then, the transverse cylinder 7 enters the reset state and pushes the slide rail 10 to reset, so that the brush roller 6 can brush the inner wall of the other long side of the cleaning tank 2 until the slide rail 10 returns to its initial position and the transverse cylinder 7 stops moving.

[0061] Specifically, the brush roller 6 is hollow inside and has multiple sets of through holes. The upper end of the brush roller 6 is connected to a water injection pipe (not shown in the figure) located in the cleaning chamber 101. When the brush roller 6 rotates, the water injection pipe will pass pure water into the brush roller 6 so that the brush roller 6 is in a wet state to scrub the inner wall of the cleaning tank 2.

[0062] Repeating this process multiple times will clean the inner wall of the cleaning tank 2, preventing residual liquid from adhering to the side wall of the cleaning tank 2. This will prevent the new liquid from mixing with the old liquid during subsequent liquid changes, which could lead to changes in the concentration of the cleaning agent and result in poor cleaning effect.

[0063] A cleaning method for a silicon wafer DHF cleaning machine is also proposed, characterized by employing a silicon wafer DHF cleaning machine based on the RCA cleaning method as described above, comprising the following steps:

[0064] Step 1: After the silicon wafer cleaning is completed, when changing the solution, waste liquid will remain on the side walls of the cleaning tank 2. After the silicon wafer is removed from the cleaning tank 2, the vertical linear guide shaft 3 drives the mounting plate 4 to descend so that the brush roller 6 can be inserted into the cleaning tank 2 and contact the inner wall of the cleaning tank 2.

[0065] Step 2: Start the motor, and the brush roller 6 will continue to rotate in the same direction. Then, the longitudinal cylinder 8 will retract and pull the moving rail 13 to slide along the width of the cleaning tank 2 until it reaches the end of its stroke. Then the longitudinal cylinder 8 will stop and the transverse cylinder 7 will move.

[0066] Step 3: The horizontal cylinder 7 retracts and pulls the slide rail 10 to slide along the length of the cleaning tank 2 until it reaches the end of its stroke. Then the horizontal cylinder 7 stops and the vertical cylinder 8 performs a reset action, pushing the moving rail 13 to reset along the width of the cleaning tank 2.

[0067] Step 4: After the longitudinal cylinder 8 is reset, the transverse cylinder 7 is reset, pushing the slide rail 10 to slide along the length of the cleaning tank 2 until the transverse cylinder 7 stops moving. Then the brush roller 6 returns to its initial position and moves around the inner wall of the cleaning tank 2 for one revolution. During this process, the continuously rotating brush roller 6 brushes the inner wall of the cleaning tank 2 to clean the residual liquid on the inner wall of the cleaning tank 2.

[0068] Step 5: After cleaning is completed, the vertical linear guide shaft 3 pulls the mounting plate 4 to rise and reset.

[0069] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0070] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method, comprising a main frame unit, an FFU purification unit, a chemical solution unit, an acid pickling tank unit, and a wafer transfer system; the main frame unit includes a cleaning cabinet (1), and the FFU purification unit is disposed above the interior of the cleaning cabinet (1). The pickling tank unit includes a cleaning tank (2) installed inside the cleaning chamber (101) of the cleaning cabinet (1), characterized in that: The cleaning chamber (101) is also provided with an installation plate (4), which is connected to a lifting component provided in the cleaning chamber (101). The lifting component can drive the installation plate (4) to rise and fall relative to the cleaning cabinet (1). A brush roller (6) is provided on the mounting plate (4). The brush roller (6) is connected to a longitudinal moving component provided on the mounting plate (4). The longitudinal moving component can drive the brush roller (6) to slide along the width direction of the mounting plate (4). The mounting plate (4) is also provided with a transverse moving component, which can drive the brush roller (6) to slide along the length direction of the mounting plate (4).

2. The wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 1, characterized in that, The lifting component includes a vertical linear guide shaft (3) installed on the inner wall of the cleaning chamber (101), and the vertical linear guide shaft (3) is connected to the mounting plate (4).

3. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 2, characterized in that, The longitudinal moving component includes a longitudinal driving component and a limiting component. The limiting component includes plug tubes (9) symmetrically arranged along the length direction of the mounting plate (4). Each plug tube (9) is slidably provided with a slide plate (1301). A moving rail (13) is provided between the two sets of slide plates (1301). The brush roller (6) is rotatably installed in the moving rail (13).

4. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 3, characterized in that, The longitudinal drive component includes a longitudinal cylinder (8) arranged along the width direction of the mounting plate (4), and the telescopic end of the longitudinal cylinder (8) is connected to the moving rail (13).

5. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 2, characterized in that, The lateral movement assembly includes a lateral drive and a mounting box (11). The lateral drive includes a lateral cylinder (7) arranged along the length of the mounting plate (4). The telescopic end of the lateral cylinder (7) is slidably arranged in a slide rail (10). The slide rail (10) is mounted on the mounting box (11). The brush roller (6) is rotatably mounted in the mounting box (11) and connected to a rotating structure arranged in the mounting box (11).

6. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 5, characterized in that, The rotating structure includes a motor mounted on the mounting box (11), the output shaft of which extends into the mounting box (11) and is connected to the brush roller (6) via a chain (12).

7. A wafer silicon wafer DHF cleaning machine based on RCA cleaning method according to claim 2, characterized in that, A limiting ring (5) is provided inside the mounting plate (4). The outline of the limiting ring (5) is the same as the outline of the inner wall of the cleaning tank (2). The brush shaft of the brush roller (6) is in contact with the limiting ring (5).

8. A cleaning method for a silicon wafer DHF cleaning machine, characterized in that, The wafer silicon wafer DHF cleaning machine based on the RCA cleaning method described in claim 1 includes the following steps: Step 1: After the silicon wafer is cleaned, when the liquid is changed, waste liquid will remain on the side walls of the cleaning tank (2). After the silicon wafer is removed from the cleaning tank (2), the vertical linear guide shaft (3) is driven to drive the mounting plate (4) to descend so that the brush roller (6) is inserted into the cleaning tank (2) and contacts the inner wall of the cleaning tank (2). Step 2: Start the motor, the brush roller (6) rotates continuously in the same direction, then the longitudinal cylinder (8) retracts and pulls the moving rail (13) to slide along the width direction of the cleaning tank (2) until it moves to the end of the stroke, then the longitudinal cylinder (8) stops and the transverse cylinder (7) moves. Step 3: The horizontal cylinder (7) retracts and pulls the slide rail (10) to slide along the length of the cleaning tank (2) until it reaches the end of its stroke. Then the horizontal cylinder (7) stops, and the vertical cylinder (8) performs a reset action, pushing the moving rail (13) to reset along the width of the cleaning tank (2). Step 4: After the longitudinal cylinder (8) is reset, the transverse cylinder (7) is reset and pushes the slide rail (10) to slide along the length of the cleaning tank (2) until the transverse cylinder (7) stops moving. Then the brush roller (6) returns to its initial position and moves around the inner wall of the cleaning tank (2) for one revolution. During this process, the continuously rotating brush roller (6) brushes the inner wall of the cleaning tank (2) to clean the residual liquid on the inner wall of the cleaning tank (2). Step 5: After cleaning is completed, the vertical linear guide shaft (3) pulls the mounting plate (4) to rise and reset.

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