Wafer cleaning device

Abstract

The invention discloses a wafer cleaning device, comprising a box body and a cleaning component therein, wherein the box body has a top cover, side walls and a bottom plate, the top cover comprises a top cover base and a maintenance door, the top cover base is provided with an opening matching the maintenance door, the maintenance door is detachably installed at the opening for the convenience of maintaining the cleaning component, the lower surface of the maintenance door is inclined from the middle to both sides, and the lower surface of the top cover base is also inclined from the middle to both sides, so as to guide the liquid formed on the lower surface of the top cover to flow down obliquely, thereby preventing the liquid from directly dripping on the wafer surface to cause pollution.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing equipment, and in particular to a wafer cleaning device. Background Art

[0002] Wafer manufacturing is a key link that restricts the development of the ultra-large-scale integrated circuit (IC) industry. As the feature size of integrated circuits continues to shrink, the requirements for wafer surface quality are getting higher and higher, so the control of defect size and quantity in the wafer manufacturing process is becoming more and more stringent. In the logic chip process, when the feature size develops from 14nm to 7nm, the control range of contaminants above 19nm is also reduced from 100 to 50, gradually approaching the limits of cleaning technology and measurement technology. Contaminants are an important factor that causes the quality of the wafer surface to deteriorate and even cause defects. Therefore, cleaning technology is needed to remove contaminants on the wafer surface to obtain an ultra-clean surface, especially in the post-cleaning and drying of chemical mechanical polishing (CMP, Chemical Mechanical Polishing), it is easy to encounter liquid mark defects (also known as water marks), which will cause local changes in oxide thickness and seriously affect chip manufacturing yield.

[0003] The inside of the box for cleaning wafers is an environment with high humidity. Liquid droplets are easily condensed on the top of the box, and some liquid will be thrown onto the top cover of the box during the cleaning process. As a result, when the wafer cleaning is completed and the robot takes the wafer, the dirty water on the top cover of the box will drip down, contaminating the cleaned wafer surface, causing secondary contamination of the wafer surface, and seriously affecting the cleaning effect. Summary of the invention

[0004] An embodiment of the present invention provides a wafer cleaning device, aiming to solve at least one of the technical problems existing in the prior art.

[0005] An embodiment of the present invention provides a wafer cleaning device, including a box body and a cleaning component inside the box body, wherein the box body has a top cover, side walls and a bottom plate, the top cover includes a top cover base and a maintenance door, the top cover base is provided with an opening matching the maintenance door, the maintenance door is detachably installed at the opening to facilitate the maintenance of the cleaning component, the lower surface of the maintenance door is inclined from the middle to both sides, and the lower surface of the top cover base is also inclined from the middle to both sides to guide the liquid formed on the lower surface of the top cover to flow down obliquely, thereby preventing the liquid from dripping directly on the wafer surface and causing contamination.

[0006] In one embodiment, the top cover base includes a frame, a cover plate and inclined plates on both sides. The cover plate is provided with the opening, the frame is fixed above the cover plate around the opening, and two inclined plates are fixed below the cover plate and are respectively located on both sides of the opening.

[0007] In one embodiment, the maintenance door is inserted into the frame for installation.

[0008] In one embodiment, the cover plate is provided with a water collecting trough on the peripheral side of the opening, the water collecting trough is located inside the frame body, and is used to collect liquid flowing obliquely along the lower surface of the maintenance door after the maintenance door is inserted into the frame body.

[0009] In one embodiment, a water guide channel leading from the water collecting tank to the inclined plate is provided on the cover plate.

[0010] In one embodiment, a gap is provided between the inclined plate and the side wall, so that the liquid flowing from the sump onto the inclined plate can flow down through the gap.

[0011] In one embodiment, the maintenance door includes a main body, an edge portion extending outward from the upper surface of the main body, and an extension portion extending downward from the bottom end of the main body; when the main body is inserted into the frame, the edge portion rests on the frame and the extension portion extends into the water collection tank.

[0012] In one embodiment, the top cover is made of plastic.

[0013] In one embodiment, the inclination angle of the lower surface of the maintenance door is not less than 5°.

[0014] In one embodiment, the inclination angle of the lower surface of the top cover base is not less than 5°.

[0015] The beneficial effects of the embodiments of the present invention include: being able to guide the liquid formed on the lower surface of the top cover to flow downward obliquely, thereby preventing the liquid from directly dripping onto the surface of the wafer and causing contamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The advantages of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings, but these drawings are only schematic and do not limit the scope of protection of the present invention, wherein:

[0017] Figure 1 A three-dimensional perspective view of a wafer cleaning device provided by an embodiment of the present invention;

[0018] Figure 2 Shows Figure 1 Maintenance door in the

[0019] Figure 3 Shows Figure 1 The top cover base in the middle;

[0020] Figure 4 for Figure 1 A cross-sectional view of a wafer cleaning device;

[0021] Figure 5 Shows Figure 4 Part of the structure and water conduction principle. DETAILED DESCRIPTION

[0022] The technical scheme of the present invention is described in detail below in conjunction with specific embodiments and their accompanying drawings. The embodiments recorded herein are specific embodiments of the present invention, which are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be understood as limitations on the embodiments of the present invention and the scope of protection of the present invention. It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. In addition to the embodiments recorded herein, those skilled in the art can also adopt other obvious technical solutions based on the contents disclosed in the claims of this application and its specification, which include technical solutions that adopt any obvious replacements and modifications to the embodiments recorded herein. It should be understood that, unless otherwise specified, for ease of understanding, the following description of the specific embodiments of the present invention is based on the description of the relevant equipment, devices, components, etc. in the original static natural state without external control signals and driving forces.

[0023] In addition, it should be noted that the terms used in this application to indicate orientation, such as front, back, up, down, left, right, top, bottom, front, back, horizontal, vertical, etc., are merely for convenience of description to help understand relative positions or directions, and are not intended to limit the orientation of any device or structure.

[0024] In order to illustrate the technical solution of the present invention, the following description will be given with reference to the accompanying drawings and in combination with embodiments.

[0025] In this application, chemical mechanical polishing is also referred to as chemical mechanical planarization, and a wafer is also referred to as a chip, a silicon wafer, a base wafer or a substrate, which have the same meaning and practical function.

[0026] Figures 1 to 4 The wafer cleaning device 1 disclosed in the present application is shown, which includes a cleaning component and a box for accommodating the cleaning component, wherein the box has a top cover 100 , a side wall 110 and a bottom plate 120 .

[0027] Exemplarily, the cleaning component includes a cleaning part, a liquid supply part, and a wafer supporting part.

[0028] like Figure 1 and Figure 4As shown, in one embodiment, the cleaning part includes a cylindrical cleaning brush 31, which is arranged on both sides of the wafer W and rolls around its axis. The upper and lower cleaning brushes 31 are against the upper and lower surfaces of the wafer W, and scrub the contaminants on the surface of the wafer W. During the scrubbing process, the upper and lower cleaning brushes 31 are filled with deionized water and keep rolling at a certain speed. The cleaning brush 31 can be made of a porous material, such as polyvinyl alcohol, and the cleaning brush 31 can absorb a large amount of cleaning liquid used to clean the surface of the wafer W. The rolling cleaning brush 31 contacts the rotating wafer W and scrubs to remove the contaminants on the surface of the wafer W.

[0029] Liquid supply parts (not shown) may be disposed on the upper and lower sides of the wafer W to supply cleaning liquid for cleaning the wafer W, thereby completing the cleaning of the front and back sides of the wafer W simultaneously.

[0030] The wafer support portion (not shown) is used to horizontally support the wafer W and drive the wafer W to rotate.

[0031] It can be understood that the cleaning component can be implemented in many ways, such as brush cleaning, brushless cleaning, megasonic cleaning, etc., and can be both vertical cleaning and horizontal cleaning. The drawings of the present application only exemplarily show an embodiment of horizontal brush cleaning. It should be understood that other cleaning components that can realize the wafer W cleaning function should fall within the scope of protection of the present application.

[0032] like Figure 1 and Figure 4 As shown, the box body is a fully enclosed box body and can be surrounded by six sides.

[0033] In one embodiment, the side wall 110 includes a front plate, a rear plate, a left plate and a right plate, the front plate is arranged opposite to the rear plate, and the left plate is arranged opposite to the right plate. A film taking port is provided on the front plate, and the robot 40 performs film taking and placing operations through the film taking port. The film taking port is an openable and closable window. Before cleaning, the film taking port is opened, and the robot 40 carries the wafer W through the film taking port into the box, and then places the wafer W in the cleaning position; during the cleaning process, the film taking port is closed to maintain a closed environment in the box; after cleaning, the film taking port is opened, and the robot 40 extends into the box through the film taking port to take out the wafer W.

[0034] It should be noted that the lower surface of the top cover 100 is located inside the box. During the cleaning process, on the one hand, due to the high humidity inside the box, water vapor will condense on the lower surface of the top cover 100 to form droplets. On the other hand, whether horizontal cleaning or vertical cleaning, a rotation method is generally used, which will throw the liquid onto the top cover 100 of the box, causing the sewage on the top cover 100 of the box to drip down and contaminate the surface of the wafer W that has been cleaned, causing secondary contamination of the surface of the wafer W, seriously affecting the cleaning effect.

[0035] In order to solve the above problems, Figures 1 to 4 As shown, the top cover 100 includes a top cover base 10 and a maintenance door 20. The top cover base 10 is provided with an opening 13 matching the maintenance door 20. The maintenance door 20 is installed at the opening 13. The lower surface of the maintenance door 20 is inclined from the middle to both sides. The lower surface of the top cover base 10 is also inclined from the middle to both sides to guide the liquid formed on the lower surface of the top cover 100 to flow down obliquely, thereby avoiding the liquid from dripping directly on the surface of the wafer W to cause contamination.

[0036] In the embodiment of the present invention, the top cover 100 of the box body of the wafer cleaning device 1 is a double-layer structure, and the shape of its lower surface is generally inclined from the middle to both sides. The liquid formed on the lower surface of the top cover 100 will flow down to the bottom of the box body along the inclined surfaces on both sides under the action of gravity, which can effectively prevent the sewage from dripping from the top cover 100 and causing secondary pollution to the wafer W.

[0037] In one embodiment, the top cover 100 is made of corrosion-resistant plastic, such as PP, PVDF, PTFE, PEEK, etc. The lower surface of the top cover 100 is polished, and the smooth lower surface is conducive to guiding water flow. Optionally, the lower surface of the top cover 100 is covered with a hydrophilic material layer to further improve the water guiding effect of the top cover 100.

[0038] In one embodiment, the inclination angle of the lower surface of the maintenance door 20 is not less than 5°. Further, the inclination angle of the lower surface of the maintenance door 20 is not less than 20°, which can drain water smoothly. Considering the actual product structure limitations, the inclination angle of the lower surface of the maintenance door 20 is preferably between 20° and 30°, which can achieve a good diversion effect and will not take up too much space.

[0039] Similarly, the inclination angle of the lower surface of the top cover base 10 is not less than 5°, and may be not less than 20°, and is preferably between 20° and 30°.

[0040] like Figure 1 As shown, in one embodiment, the maintenance door 20 is detachably mounted at the opening 13 to facilitate maintenance of the cleaning assembly. Figure 1 As shown, mounting holes are provided at corresponding positions of the maintenance door 20 and the top cover base 10, and the two are fixed together by a fixing knob.

[0041] This embodiment realizes that when the interior of the box is maintained, only the maintenance door 20 needs to be removed to replace the cleaning brush 31 and other structures, avoiding the need to remove the entire box top cover 100, thereby improving production efficiency.

[0042] like Figure 3As shown, the top cover base 10 includes a frame 11, a cover plate 12 and inclined plates 16 on both sides. The cover plate 12 is provided with an opening 13. The frame 11 is fixed above the cover plate 12 around the opening 13. The maintenance door 20 is inserted into the frame 11 for installation. The two inclined plates 16 are fixed under the cover plate 12 and are respectively located on both sides of the opening 13.

[0043] In one embodiment, the frame 11 is a rectangular frame, and its long side is parallel to the cleaning brush 31 in the cleaning assembly, so that the cleaning brush 31 can be taken out or put in through the frame 11 for maintenance.

[0044] In one embodiment, the cover plate 12 is mounted on the side wall 110 , thereby fixing the top cover 100 .

[0045] In one embodiment, the top cover 100 and the side wall 110 are connected by screws, and a sealing structure is provided at the connection end of the top cover 100 and the side wall 110 to ensure good sealing of the box. Specifically, the sealing structure can be realized by a sealing strip made of fluororubber.

[0046] In one embodiment, the inclined plates 16 on both sides are located in the box body and are inclined downward from the opening 13 toward the side walls 110 on both sides. Correspondingly, the lower surface of the maintenance door 20 is inclined downward from the middle to both sides.

[0047] like Figure 3 As shown, the cover plate 12 is provided with a water collecting trough 14 around the opening 13. The water collecting trough 14 is located inside the frame 11 and arranged along the inner surface of the frame 11. It is used to collect liquid that flows obliquely along the lower surface of the maintenance door 20 after the maintenance door 20 is inserted into the frame 11.

[0048] like Figure 4 As shown, a water guide channel 15 is provided on the cover plate 12, which leads from the water collecting tank 14 to the inclined plate 16.

[0049] In one embodiment, the water channel 15 passes through the cover plate 12 and communicates with the water collecting tank 14 and opens downwardly through the opening 13 to the inclined plate 16. The opening of the water channel 15 at the cover plate 12 is blocked at ordinary times, and the opening can be opened during maintenance, and liquid can be poured into the water channel 15 through the opening to rinse the various components of the top cover 100 to avoid blockage caused by crystallization after long-term use.

[0050] It should be understood that Figure 4 Only one implementation of the water channel 15 is shown. The water channel 15 can also be implemented in many other ways, and is not limited to Figure 4 For example, any structure that can conduct the water collection tank 14 and the inclined plate 16 should fall within the protection scope of this application.

[0051] like Figure 4As shown, there is a gap between the inclined plate 16 and the side wall 110, so that the liquid flowing from the sump 14 to the inclined plate 16 can flow down to the bottom of the box through the gap.

[0052] like Figure 2 and Figure 4 As shown, in one embodiment, the maintenance door 20 includes a main body 21 , an edge 22 extending outward from an upper surface of the main body 21 , and a protruding portion 23 extending downward from a bottom end of the main body 21 .

[0053] like Figure 4 As shown, after the main body 21 is inserted into the frame 11 , the edge portion 22 is placed on the frame 11 for fixation, and the extension portion 23 extends into the water collecting tank 14 .

[0054] like Figure 4 As shown, the main body 21 has a lower surface that slopes downward from the middle to both sides, which is used to guide the liquid to flow into the water collecting tank 14.

[0055] like Figure 5 As shown by the dotted arrow, the liquid flows from the lower surface of the maintenance door 20 to the sump 14, flows through the water guide channel 15 to the upper surface of the inclined plate 16, and then flows down through the gap; it flows obliquely along the inclined plate 16 to the bottom of the box.

[0056] In one embodiment, Figure 1 As shown, a discharge port 130 for discharging waste gas and / or waste liquid is provided on the bottom plate 120, and the discharge port 130 is connected to the gas-liquid recovery pipeline. Furthermore, the upper surface of the bottom plate 120 is an inclined surface, and the discharge port 130 is the lowest point. When the liquid flows to the bottom of the box, it will converge along the bottom plate 120 to the discharge port 130 for discharge.

[0057] In summary, the present application designs the top cover 100 of the box body as a double-layer structure with two sides tilted. The cleaning brush 31 throws the liquid on the top cover base 10 and the maintenance door 20. Due to the effect of gravity, the liquid will flow down to the bottom of the box body along the inclined surface, and then be discharged from the box body along the discharge port 130, which can effectively prevent the top cover 100 from dripping sewage and causing secondary pollution to the wafer W. In addition, the upper maintenance door 20 is detachable, which is convenient for equipment maintenance and improves production efficiency. The top cover base 10 and the maintenance door 20 are both corrosion-resistant plastics, which can reduce the maintenance cost of the top cover 100, thereby reducing costs.

[0058] The drawings of this specification are schematic diagrams, which assist in explaining the concept of the present invention and schematically show the shapes of various parts and their mutual relationships. It should be understood that in order to clearly show the structures of various components of the embodiments of the present invention, the drawings are not drawn according to the same scale, and the same reference numerals are used to represent the same parts in the drawings.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0060] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A wafer cleaning device, characterized in that: The invention comprises a box body and a cleaning component therein, wherein the box body comprises a top cover, a side wall and a bottom plate, the top cover comprises a top cover base and a maintenance door, the top cover base is provided with an opening matching with the maintenance door, the maintenance door is detachably mounted at the opening for facilitating maintenance of the cleaning component, the lower surface of the maintenance door is inclined from the middle to both sides, and the lower surface of the top cover base is also inclined from the middle to both sides, so as to guide the liquid formed on the lower surface of the top cover to flow down obliquely, thereby preventing the liquid from directly dripping on the surface of the wafer to cause contamination; The top cover base comprises a frame, a cover plate and inclined plates on both sides, the cover plate is provided with the opening, the frame is fixed above the cover plate around the opening, and two inclined plates are fixed below the cover plate and are respectively located on both sides of the opening; The maintenance door is inserted into the frame for installation; The cover plate is provided with a water collecting trough on the peripheral side of the opening, and the water collecting trough is located inside the frame body. The maintenance door has a protruding portion, and after the maintenance door is inserted into the frame body, the protruding portion extends into the water collecting trough, and the water collecting trough collects liquid that flows obliquely along the lower surface of the maintenance door.

2. The wafer cleaning device according to claim 1, characterized in that: The cover plate is provided with a water guide channel leading from the water collecting tank to the inclined plate.

3. The wafer cleaning device according to claim 1, characterized in that: There is a gap between the inclined plate and the side wall, which is used for the liquid flowing from the water collecting tank to the inclined plate to flow down through the gap.

4. The wafer cleaning device according to claim 1, characterized in that: The maintenance door comprises a main body, an edge extending outward from the upper surface of the main body, and a protruding portion extending downward from the bottom end of the main body; when the main body is inserted into the frame, the edge rests on the frame and the protruding portion extends into the water collection tank.

5. The wafer cleaning device according to claim 1, characterized in that: The material of the top cover is plastic.

6. The wafer cleaning device according to claim 1, characterized in that: The inclination angle of the lower surface of the maintenance door is not less than 5°.

7. The wafer cleaning device according to any one of claims 1 to 6, characterized in that: The inclination angle of the lower surface of the top cover base is not less than 5°.

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