A cleaning device for waxed carriers of a polishing machine

Abstract

This utility model discloses a cleaning device for a wax-coated carrier of a polishing machine, comprising an immersion tank, a washing tank, and a basket. The basket is used to hold the wax-coated carrier to be cleaned. There are several immersion tanks and washing tanks. The immersion tank holds an alkaline solution and holds the basket containing the wax-coated carrier, allowing the carrier to be immersed in the alkaline solution to remove impurities. The washing tank has an inlet and an overflow hole. The washing tank holds the basket after immersion and impurity removal. The inlet is used to add cleaning water, and the overflow hole is used to drain excess cleaning water. The combination of the inlet and overflow hole creates a flowing stream of cleaning water to rinse the basket. The cleaning device provided by this application has a simple structure, low price, and easy operation. It can reduce the residue of particles on the carrier surface, thereby reducing the incidence of shallow pits, effectively improving product yield, and reducing the company's production costs.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor manufacturing technology, and specifically relates to a cleaning device for a wax coating carrier used in a polishing machine. Background Technology

[0002] In the process of surface planarization of silicon substrates, CMP (chemical mechanical polishing) is an indispensable step, and single-wafer polishing machines are a process to achieve atomic-level flatness of silicon substrates.

[0003] In the operation of a single-wafer polishing machine, the general process is as follows: 1. Apply wax in the wax application area, that is, apply special wax to the back of the wafer onto a circular block carrier; 2. Achieve the target removal amount and a better flatness parameter through three processes: coarse polishing, medium polishing, and fine polishing.

[0004] In the manufacturing process of single-wafer polishing machines, foreign objects on the substrate and the back side of the wafer can cause uneven contact pressure between the wafer and the polishing pad during polishing. If particles are present on the back side, the pressure will be greater at that point, resulting in over-polishing. This appears as a shallow pit, called a "Dimple," in the flatness map (used to visualize the flatness deviation of different areas on the wafer surface) after polishing. The presence of shallow pits will worsen the roughness of this area in back-end semiconductor processes, such as epitaxy, and prevent proper focusing in photolithography, thus causing defects. Since each defective silicon wafer represents a huge loss in back-end processes, which is unacceptable to customers, it is necessary to reduce the occurrence rate of shallow pits on the substrate side, i.e., to improve the cleanliness of the substrate surface.

[0005] The particles on the carrier surface are mostly caused by the SiO2 abrasive in the polishing slurry agglomerating on the carrier and forming crystals as the polishing time increases. In the existing technology, blades are often used to scrape off the crystals on the carrier surface, which not only does not clean thoroughly, but also easily causes irreversible damage to the carrier surface. Utility Model Content

[0006] The purpose of this invention is to provide a cleaning device for a waxing carrier of a polishing machine to address the shortcomings of existing technologies, thereby improving the cleanliness of the CMP carrier (Block) surface.

[0007] The objective of this utility model is achieved through the following technical solution: A cleaning device for a waxing carrier of a polishing machine includes an immersion tank, a washing tank, and a basket. The basket is used to load the vehicle to be cleaned and waxed. There are several soaking tanks and several washing tanks; The soaking tank is used to hold alkaline solution and place the basket containing the waxing carrier to be cleaned in the alkaline solution to remove impurities. The washing tank is equipped with a water inlet and an overflow hole. The washing tank is used to place the basket after soaking and removing impurities. The water inlet is used to add cleaning water, and the overflow hole is used to discharge excess cleaning water. The combination of the water inlet and the overflow hole allows the continuously added cleaning water to form flowing water to rinse the basket.

[0008] Preferably, there are multiple soaking tanks and multiple washing tanks.

[0009] Preferably, the soaking tanks are interconnected; The water washing tanks are interconnected.

[0010] Preferably, the soaking tank and the washing tank are arranged in a linear array, and two adjacent soaking tanks and two adjacent washing tanks share a side plate, with a connecting hole at the bottom of the side plate.

[0011] Preferably, the number of washing tanks is the same as the number of soaking tanks, and the washing tanks and soaking tanks are arranged side by side.

[0012] Preferably, the number of water inlets is one.

[0013] Preferably, the soaking tank is provided with a cover plate.

[0014] Preferably, the basket includes two outer side plates and several intermediate side plates located between the two outer side plates. The outer side plates and the intermediate side plates are connected in series by three connecting columns. There is a certain space between two adjacent side plates for accommodating the cleaning and waxing carrier. The three connecting columns are triangular in shape for supporting the cleaning and waxing carrier.

[0015] Preferably, the basket also includes a handle.

[0016] Preferably, the volume of a single soaking tank and a washing tank is adapted to the volume of the basket.

[0017] The cleaning device provided in this application has a simple structure, low price, and easy operation. It can reduce the residual particles on the surface of the carrier, thereby reducing the occurrence of shallow pits, effectively improving the product yield, and reducing the company's production costs. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the cleaning device provided in this application; Figure 2 yes Figure 1Another structural diagram from a different perspective; Figure 3 This is a three-dimensional structural diagram of the basket provided in this application; Figure 4 This is a schematic diagram of the front view structure of the basket provided in this application; Explanation of reference numerals in the attached figures: 1-Soaking tank; 11-Cover plate; 12-Water inlet; 2-Washing tank; 21-Water inlet; 22-Overflow hole; 23-Connecting hole; 3-Basket; 31-Outer side plate; 32-Middle side plate; 33-Connecting column; 34-Handle; 4-Carrier to be cleaned and waxed. Detailed Implementation

[0019] This application provides a cleaning device for a wax-coated carrier of a polishing machine, such as... Figures 1-4 As shown, it includes a soaking tank 1, a washing tank 2, and a basket 3.

[0020] The basket 3 is used to load the waxing carrier 4 to be cleaned, that is, the carrier of this application is placed in the basket for cleaning, which facilitates the loading and unloading of the carrier during the cleaning process.

[0021] There are several soaking tanks 1 and several washing tanks 2. Preferably, there are multiple soaking tanks 1 and multiple washing tanks 2. The volume of each soaking tank 1 and washing tank 2 is adapted to the volume of the basket 3. Each soaking tank and each washing tank is used to place one basket to prevent collisions and mutual interference caused by placing multiple baskets in one tank.

[0022] The soaking tank 1 is used to hold alkaline solution and place basket 3 containing the wax-coated carrier 4 to be cleaned. The wax-coated carrier 4 is first soaked in the alkaline solution for a period of time to dissolve and remove the SiO2 crystals on the carrier.

[0023] The washing tank 2 is equipped with a water inlet 21 and an overflow hole 22. The washing tank 2 is used to place the basket after soaking and cleaning. The water inlet 21 is used to add cleaning water, and the overflow hole 22 is used to discharge excess cleaning water. The combination of the water inlet 21 and the overflow hole 22 makes the continuously added cleaning water form flowing water to rinse the basket.

[0024] Since the vehicle inevitably retains some alkaline solution after being soaked in the alkaline solution, it is placed in the washing tank 2 after soaking. By continuously adding cleaning water, the alkaline on the vehicle gradually dissolves in the cleaning water, gradually increasing the alkaline concentration in the cleaning water. When the cleaning water level reaches the overflow hole 22, the excess cleaning water is discharged from the overflow hole, gradually reducing the alkaline concentration in the cleaning water. This allows the alkaline on the vehicle to be completely dissolved and discharged from the washing tank 2, thus completing the cleaning of the vehicle.

[0025] Therefore, the cleaning device provided in this application can reduce the residual particles on the surface of the carrier, thereby reducing the occurrence rate of shallow pits and achieving the goal of improving product yield and economic benefits.

[0026] Preferably, the soaking tanks 1 are interconnected; the washing tanks 2 are also interconnected, which can reduce the installation of pipelines such as water inlets, water inlet pipes, and drain outlets, and also simplify the cleaning operation.

[0027] More preferably, the soaking tank 1 and the washing tank 2 are arranged in a linear array, and two adjacent soaking tanks 1 and two adjacent washing tanks 2 share a side plate. The bottom of the side plate is provided with a connecting hole 23, which allows alkaline solution and washing water to pass through, forming a connection between each soaking tank and each washing tank.

[0028] Preferably, the number of washing tanks 2 is the same as the number of soaking tanks 1, and they are arranged side by side with the soaking tanks 1.

[0029] Preferably, there is one water inlet 21. Since the washing tanks 2 in this application are interconnected, one water inlet 21 is sufficient to add water to all the washing tanks. More preferably, the water inlet 21 and the overflow hole 22 are located on different sides of the soaking tank.

[0030] In practical use, KOH is generally prepared by mixing a high-concentration stock solution with a certain proportion of water to create a soaking solution of a specific concentration for soaking. Therefore, preferably, the soaking tank 1 is equipped with a water inlet 12 for adding a certain amount of water. More preferably, there is only one water inlet 12, so that water can be added to all the soaking tanks 1.

[0031] Preferably, the soaking tank 1 is provided with a cover plate 11, which can cover the opening of the soaking tank 1 when the basket is placed in or when it is not in use, to prevent KOH from splashing and causing safety problems.

[0032] Preferably, the water discharged from the overflow hole 22 is collected through a pipeline before being discharged.

[0033] Preferably, the basket 3 includes two outer side plates 31 and several middle side plates 32 located between the two outer side plates 31. The outer side plates 31 and the middle side plates 32 are connected in series by three connecting columns 33. There is a certain space between two adjacent side plates for placing a waxing carrier to be cleaned. One carrier is placed between every two side plates to reduce the contact between the carriers and improve the cleaning efficiency.

[0034] The three connecting posts 33 form a triangle to support the carrier to be cleaned and waxed. Using three connecting posts 33 to form a triangular support reduces the contact area with the outer edge of the carrier, allowing for a larger exposed area and better immersion in KOH.

[0035] More preferably, the connecting post 33 is circular.

[0036] Preferably, the basket 3 also includes a handle 34 for easy loading and unloading.

[0037] The cleaning device provided in this application has a simple structure, low price, and easy operation. It can reduce the residual particles on the surface of the carrier, thereby reducing the occurrence of shallow pits, effectively improving the product yield, and reducing the company's production costs.

[0038] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from its spirit and scope. Thus, if such modifications and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and modifications.

Claims

1. A cleaning device for a waxing carrier of a polishing machine, characterized in that, Includes soaking tank, washing tank, and basket; The basket is used to load the cleaning and waxing carrier; the basket includes two outer side plates and several middle side plates located between the two outer side plates. The outer side plates and the middle side plates are connected in series by three connecting columns. There is a certain space between two adjacent side plates for accommodating and placing the cleaning and waxing carrier. The three connecting columns are triangular in shape for supporting the cleaning and waxing carrier. There are several soaking tanks and several washing tanks; The soaking tank is used to hold alkaline solution and place the basket containing the waxing carrier to be cleaned in the alkaline solution to remove impurities. The washing tank is equipped with a water inlet and an overflow hole. The washing tank is used to place the basket after soaking and removing impurities. The water inlet is used to add cleaning water, and the overflow hole is used to discharge excess cleaning water. The combination of the water inlet and the overflow hole allows the continuously added cleaning water to form flowing water to rinse the basket.

2. The cleaning device for a waxing carrier of a polishing machine as described in claim 1, characterized in that, There are multiple soaking tanks and multiple washing tanks.

3. The cleaning device for a waxing carrier of a polishing machine as described in claim 2, characterized in that, The soaking tanks are interconnected. The washing tanks described are interconnected.

4. The cleaning device for a waxing carrier of a polishing machine as described in claim 3, characterized in that, The soaking tank and the washing tank are arranged in a linear array. Two adjacent soaking tanks and two adjacent washing tanks share a side plate, and the bottom of the side plate is provided with a connecting hole.

5. The cleaning device for a waxing carrier of a polishing machine as described in claim 4, characterized in that, The number of washing tanks is the same as the number of soaking tanks, and the washing tanks and soaking tanks are arranged side by side.

6. The cleaning apparatus for a waxing carrier of a polishing machine as described in claim 3, characterized in that, The number of water inlets is 1.

7. The cleaning apparatus for a waxing carrier of a polishing machine as described in claim 1, characterized in that, The soaking tank is equipped with a cover plate.

8. The cleaning apparatus for a waxing carrier of a polishing machine as described in claim 1, characterized in that, The basket also includes a handle.

9. The cleaning device for a waxing carrier of a polishing machine as described in claim 1, characterized in that, The volume of each of the soaking tanks and the washing tanks is adapted to the volume of the basket.

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