Device and method for preventing back-splashing liquid from contaminating substrate

Abstract

The present invention belongs to the field of wet processing of substrates in the semiconductor industry, specifically, a device and method for preventing back-splashing liquid from contaminating a substrate, a splash shield is installed on the nozzle, the upper end of the splash shield is connected to the nozzle, and the lower end is an open structure, at least one liquid inlet pipe is provided on the splash shield, the liquid inlet pipe is connected to a liquid inlet pipeline A, and liquid A is transported to the inside of the splash shield through the liquid inlet pipeline A, and liquid A forms a liquid film on the inner surface of the splash shield; the nozzle sprays liquid B onto the surface of the substrate, and the back-splashing liquid B formed on the surface of the substrate splashes back to the liquid film, and flows to the surface of the substrate with the liquid film, and detaches from the substrate with the rotation of the substrate. The present invention can prevent the liquid B sprayed by the nozzle from splashing to the outside of the lifting CUP, avoid affecting the humidity of the process unit, and prevent the back-splashing liquid from corroding the process unit; at the same time, the present invention can prevent the back-splashing liquid B from remaining on the inner surface of the nozzle or the splash shield, and avoid secondary contamination of the substrate in subsequent processes.

Description

Technical Field

[0001] The invention belongs to the field of wet processing of substrates in the semiconductor industry, and in particular relates to a device and a method for preventing back-splashing liquid from contaminating a substrate. Background Art

[0002] At present, there are various types of nozzles used in the field of wet processing of semiconductor substrates. Depending on the requirements of different processes, they may be columnar nozzles, fan nozzles, needle nozzles, two-fluid nozzles or other forms of nozzles. The liquid pressure used to process the substrate can be high or low, up to tens of MPa. Under the conditions of the same nozzle size and nozzle height, the higher the pressure, the more serious the backsplash formed after the liquid reaches the substrate. The backsplashed liquid may splash outside the CUP (collection cup), affecting the humidity of the process unit and causing corrosion to the process unit. In previous devices for dealing with liquid backsplash, the device was arranged above the nozzle, but no liquid film was formed on the inner wall of the device, and the backsplashed liquid remained on the inner wall of the device, with the risk of secondary contamination of the substrate in subsequent processes. Therefore, it is very important to design a device that can prevent the backsplashed liquid from splashing outside the CUP and will not cause contamination to subsequent substrates. Summary of the invention

[0003] In order to meet the cleanliness requirement of the substrate and complete the wet processing process of the substrate, the object of the present invention is to provide a device and method for preventing back-splashing liquid from contaminating the substrate.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The device of the present invention comprises a motor, a carrier platform, a lifting CUP, a nozzle and a swing arm, wherein the output end of the motor is connected to the carrier platform to drive the carrier platform to rotate, a substrate rotating with the carrier platform is placed on the carrier platform, and a lifting CUP that can be lifted and lowered is arranged on the periphery of the motor; the nozzle moves between the inner side and the outer side of the lifting CUP driven by the swing arm, the nozzle is connected to a liquid inlet pipeline B, and liquid B for process treatment of the substrate is transported to the nozzle through the liquid inlet pipeline B; a splash shield is installed on the nozzle, the upper end of the splash shield is connected to the nozzle, and the lower end is an open structure, at least one liquid inlet pipe is opened on the splash shield, the liquid inlet pipe is connected to a liquid inlet pipeline A, and liquid A is transported to the inside of the splash shield through the liquid inlet pipeline A, and liquid A forms a liquid film on the inner surface of the splash shield; the nozzle sprays liquid B onto the surface of the substrate, and liquid B formed on the surface of the substrate splashes back to the liquid film, flows to the surface of the substrate along with the liquid film, and separates from the substrate as the substrate rotates;

[0006] Wherein: the axial direction of the liquid inlet pipe is the same as the tangential direction of the splash shield, the incoming liquid A flows in along the tangential direction of the splash shield, and forms a continuous and uninterrupted liquid film on the inner surface of the splash shield under the action of centrifugal force;

[0007] The liquid inlet pipe is opened at the upper end of the splash shield, and the liquid film completely covers the inner surface of the splash shield;

[0008] The axial cross section of the splash shield is rectangular or trapezoidal, and the radial cross section of the splash shield is circular or elliptical;

[0009] The liquid inlet pipeline A is installed with a speed regulating valve for regulating the flow rate of the liquid A, or the liquid inlet pipe is installed with a speed regulating valve, and the liquid inlet pipeline A is connected with the liquid inlet pipe through the speed regulating valve;

[0010] The lower end of the splash shield is higher than the substrate, and the lower end of the splash shield is located below the lower end of the nozzle;

[0011] The method of preventing back-splashing liquid from contaminating a substrate of the present invention is as follows:

[0012] The substrate is placed on the carrier, and as the carrier rotates driven by the motor, the nozzle moves to the top of the substrate driven by the swing arm; liquid A enters the splash shield through the liquid inlet pipe, and forms a liquid film on the inner surface of the splash shield under the action of centrifugal force, and the liquid film flows downward to the surface of the substrate, and separates from the substrate as the substrate rotates;

[0013] Liquid B is sprayed onto the surface of the substrate through the nozzle to perform a process on the substrate, and is separated from the substrate as the substrate rotates; during the spraying process of liquid B, liquid B splashed back from the surface of the substrate is splashed back onto a liquid film on the inner surface of the splash shield, flows to the surface of the substrate along with the liquid film, and is separated from the substrate as the substrate rotates.

[0014] The advantages and positive effects of the present invention are:

[0015] 1. The present invention can prevent the back-splashing liquid from splashing to the outside of the lifting CUP, avoid affecting the humidity of the process unit, and prevent the back-splashing liquid from corroding the process unit.

[0016] 2. The present invention forms a liquid film on the inner surface of the splash shield, and the splashed liquid flows back to the substrate surface along with the liquid film and detaches from the substrate as the substrate rotates, which can effectively prevent the splashed liquid from remaining on the inner surface of the splash shield and prevent secondary contamination of subsequent substrates.

[0017] 3. The liquid inlet direction and liquid flow rate of the liquid inlet pipe of the present invention can be designed differently according to different nozzle shapes and process liquid pressures to meet the needs of various working conditions, and the structure is simple and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the device of the present invention;

[0019] Figure 2 for Figure 1 A local enlarged view of point A in FIG.

[0020] Figure 3 It is a structural schematic diagram of the liquid A flowing from the liquid inlet into the splash shield in the device of the present invention;

[0021] Among them: 1 is a motor, 2 is a carrier platform, 3 is a lifting CUP (collection cup), 4 is a nozzle, 5 is a swing arm, 6 is a splash cover, 7 is a liquid inlet pipe, 8 is a speed regulating valve, 9 is a liquid pipeline A, 10 is liquid B, 11 is a liquid film, and 12 is a substrate. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings.

[0023] like Figures 1 to 3 As shown, the device of the present invention includes a motor 1, a carrier 2, a lifting CUP 3, a nozzle 4, a swing arm 5, a splash shield 6, a liquid inlet pipe 7 and a speed regulating valve 8, wherein the output end of the motor 1 is connected to the carrier 2 to drive the carrier 2 to rotate, and a substrate 12 that rotates with the carrier 2 is placed on the carrier 2, and a lifting CUP 3 that can be lifted is arranged on the periphery of the motor 1. The nozzle 4 moves between the inner side and the outer side of the lifting CUP 3 driven by the swing arm 5, and the nozzle 4 is connected to a liquid inlet pipeline B, through which liquid B10 for processing the substrate is transported to the nozzle 4.

[0024] A splash shield 6 is installed on the nozzle 4. The upper end of the splash shield 6 is connected to the nozzle 4, and the lower end is an open structure. At least one liquid inlet pipe 7 is provided on the splash shield 6. The liquid inlet pipe 7 is connected to a liquid inlet pipeline A. Liquid A is transported to the inside of the splash shield 6 through the liquid inlet pipeline A. Liquid A forms a liquid film 11 on the inner surface of the splash shield 6. In this embodiment, the axial section of the splash shield 6 is rectangular or trapezoidal, and the radial section of the splash shield 6 is circular or elliptical; two liquid inlet pipes 7 are provided on the splash shield 6, and the axial direction of each liquid inlet pipe 7 is the same as the tangential direction of the splash shield 6. Liquid A can flow into the splash shield 6 from the two liquid inlet pipes 7, and the entering liquid A flows in along the tangential direction of the splash shield 6, and forms a continuous and uninterrupted liquid film 11 on the inner surface of the splash shield 6 under the action of centrifugal force. The angle between the liquid inlet pipe 7 and the inner surface of the splash shield 6 can also be set according to process requirements. The liquid inlet pipe 7 of this embodiment is opened at the upper end of the splash shield 6, and the liquid film 11 completely covers the inner surface of the splash shield 6. When the nozzle 4 is located above the substrate 12 for process treatment, the lower end of the splash shield 6 is higher than the substrate 12, and the lower end of the splash shield 6 is located below the lower end of the nozzle 4, and the distance between the splash shield 6 and the substrate 12 can be set according to the process requirements. A speed regulating valve 8 for adjusting the flow rate of liquid A is installed on the liquid inlet pipeline A9, or a speed regulating valve 8 is installed at the liquid inlet pipe 7, and the liquid inlet pipeline A9 is connected to the liquid inlet pipe 7 through the speed regulating valve 8. In this embodiment, a speed regulating valve 8 is arranged on the liquid inlet pipeline A9 connected to the liquid inlet pipe 7, and the flow rate of liquid A can be adjusted according to the process requirements through the speed regulating valve 8.

[0025] The thickness and shape of the liquid film of the present invention can be adjusted by changing the shape, height, direction of the liquid inlet and the flow rate of the liquid A of the splash shield.

[0026] The liquid A of the present invention may be pure water.

[0027] The working process of the present invention is:

[0028] The substrate 12 is located on the supporting platform 2. As the supporting platform 12 rotates driven by the motor 1, the nozzle 4 moves to the top of the substrate 12 driven by the swing arm 5. The liquid A enters the splash shield 6 through the liquid inlet pipe 7, and forms a liquid film 11 on the inner surface of the splash shield 6 under the action of centrifugal force. The liquid film 11 flows downward to the surface of the substrate 12 and separates from the substrate 12 as the substrate 12 rotates.

[0029] The liquid B10 used for processing the substrate is sprayed onto the surface of the substrate 12 through the nozzle 4. Most of the liquid B10 processes the substrate 12 and separates from the substrate 12 as the substrate 12 rotates. During the spraying process of the liquid B10, a small portion of the liquid B10 forms a backsplash from the surface of the substrate 12. The backsplashed liquid B10 backsplashes onto the liquid film 11 on the inner surface of the splash shield 6, flows back to the surface of the substrate 12 along with the liquid film 11, and then separates from the substrate 12 as the substrate 12 rotates. The backsplashed liquid B10 will not remain on the inner surface of the splash shield 6, and the inner surface of the splash shield 6 is kept clean under the protection of the liquid film 11, thereby avoiding secondary contamination of the substrate 12 in subsequent processes.

Claims

1. A device for preventing back-splashing liquid from contaminating a substrate, comprising a motor, a carrier, a lifting cup, a nozzle and a swing arm, wherein the output end of the motor is connected to the carrier to drive the carrier to rotate, a substrate rotating with the carrier is placed on the carrier, and a lifting cup that can be lifted is arranged on the periphery of the motor; the nozzle moves between the inner side and the outer side of the lifting cup driven by the swing arm, the nozzle is connected to a liquid inlet pipeline B, and liquid B for processing the substrate is transported to the nozzle through the liquid inlet pipeline B; the characteristics are: The nozzle (4) is provided with a splash shield (6), the upper end of which is connected to the nozzle (4) and the lower end of which is an open structure. The splash shield (6) is provided with at least one liquid inlet pipe (7), the liquid inlet pipe (7) being connected to a liquid inlet pipeline A, through which liquid A is transported to the inside of the splash shield (6), and the liquid A forms a liquid film (11) on the inner surface of the splash shield (6); the nozzle (4) sprays liquid B onto the surface of the substrate (12), and the liquid B that forms a backsplash on the surface of the substrate (12) is backsplashed onto the liquid film (11), flows to the surface of the substrate (12) along with the liquid film (11), and separates from the substrate (12) as the substrate (12) rotates.

2. The device for preventing back-splashing liquid from contaminating a substrate according to claim 1, characterized in that: The axial direction of the liquid inlet pipe (7) is the same as the tangential direction of the splash shield (6), and the incoming liquid A flows in along the tangential direction of the splash shield (6) and forms a continuous and uninterrupted liquid film (11) on the inner surface of the splash shield (6) under the action of centrifugal force.

3. The device for preventing back-splashing liquid from contaminating a substrate according to claim 2, characterized in that: The liquid inlet pipe (7) is opened at the upper end of the splash shield (6), and the liquid film (11) completely covers the inner surface of the splash shield (6).

4. The device for preventing back-splashing liquid from contaminating a substrate according to claim 2, characterized in that: The axial cross-section of the splash shield (6) is rectangular or trapezoidal, and the radial cross-section of the splash shield (6) is circular or elliptical.

5. The device for preventing back-splashing liquid from contaminating a substrate according to claim 1, characterized in that: The liquid inlet pipeline A (9) is provided with a speed regulating valve (8) for regulating the flow rate of the liquid A, or the liquid inlet pipe (7) is provided with a speed regulating valve (8), and the liquid inlet pipeline A (9) is connected to the liquid inlet pipe (7) via the speed regulating valve (8).

6. The device for preventing back-splashing liquid from contaminating a substrate according to claim 1, characterized in that: The lower end of the splash shield (6) is higher than the base plate (12), and the lower end of the splash shield (6) is located below the lower end of the nozzle (4).

7. A method for preparing a substrate using the device according to any one of claims 1 to 6, characterized in that: The substrate (12) is located on the support platform (2), and as the support platform (2) rotates under the drive of the motor (1), the nozzle (4) moves to the top of the substrate (12) under the drive of the swing arm (5); liquid A enters the splash shield (6) through the liquid inlet pipe (7), and forms a liquid film (11) on the inner surface of the splash shield (6) under the action of centrifugal force, and the liquid film (11) flows downward to the surface of the substrate (12), and separates from the substrate (12) as the substrate (12) rotates; The liquid B (10) is sprayed onto the surface of the substrate (12) through the nozzle (4), the substrate (12) is subjected to a process treatment, and the liquid B (10) is separated from the substrate (12) as the substrate (12) rotates. During the spraying process of the liquid B (10), the liquid B (10) formed by backsplashing on the surface of the substrate (12) is backsplashed onto the liquid film (11) on the inner surface of the splash shield (6), and flows along the liquid film (11) to the surface of the substrate (12), and then separates from the substrate (12) as the substrate (12) rotates.

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