Apparatus and method for cleaning edges of silicon wafers

Abstract

The present disclosure relates to an apparatus and a method for cleaning the edge of a silicon wafer, the apparatus comprising a droplet supply member having an opening downward liquid outlet for providing a cleaning liquid, a receiving member being arrangeable below the liquid outlet during a cleaning operation and having a receiving surface for receiving the cleaning liquid from the liquid outlet, and a vacuum device connected to the droplet supply member for creating a weak vacuum inside the droplet supply member, such that droplets of the cleaning liquid from the liquid outlet can be held between the liquid outlet and the receiving surface under the action of the weak vacuum and a surface tension generated at the receiving surface, in order to clean the edge of a silicon wafer inserted between the liquid outlet and the receiving surface thoroughly and effectively.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor manufacturing technology, and more specifically, to apparatus and methods for cleaning the edges of silicon wafers. Background Technology

[0002] In semiconductor integrated circuits, contaminants on the surface of silicon wafers can have a serious impact on the performance, yield, and reliability of devices. Therefore, multiple cleaning processes are incorporated into silicon wafer manufacturing to remove contaminants.

[0003] Currently, the main cleaning equipment includes single-wafer cleaning machines, which remove contaminants based on the oxidation of O3 and the etching mechanism of HF on silicon dioxide. In single-wafer cleaning, the silicon wafer is fixed by an edge clamping mechanism, and cleaning fluid is sprayed onto the high-speed rotating wafer surface through an upper pipeline. Under centrifugal force, the cleaning fluid spreads across the entire wafer surface, achieving the cleaning effect. Finally, the wafer is dried by N2 purging while rotating at high speed.

[0004] However, the centrifugal force generated by the high-speed rotation of the silicon wafer makes it difficult for the cleaning solution on the surface of the silicon wafer to reach the edge of the wafer, resulting in inadequate cleaning of the edge of the silicon wafer and reducing the overall quality of the silicon wafer. Summary of the Invention

[0005] This section provides a general overview of this disclosure, rather than a full disclosure of the entire scope or all features of this disclosure.

[0006] The purpose of this disclosure is to provide an apparatus for cleaning silicon wafer edges that can thoroughly and effectively clean the edges of silicon wafers.

[0007] To achieve the above objectives, according to one aspect of this disclosure, an apparatus for cleaning the edges of a silicon wafer is provided, comprising:

[0008] A droplet supply component having a downward-facing outlet for supplying cleaning fluid;

[0009] A receiving component, which is positioned below the outlet during cleaning operations and has a receiving surface for receiving cleaning fluid from the outlet; and

[0010] A vacuum device connected to a droplet supply component is used to create a weak vacuum inside the droplet supply component, so that droplets of cleaning fluid from the outlet can be held between the outlet and the receiving surface under the action of the weak vacuum and the surface tension generated at the receiving surface, so as to clean the edge of the silicon wafer inserted between the outlet and the receiving surface.

[0011] The aforementioned apparatus for cleaning the edge of a silicon wafer may further include a liquid supply device, which includes a liquid supply line communicating internally with the droplet supply component for supplying cleaning liquid to the droplet supply component, so that as the edge of the silicon wafer is cleaned, droplets of cleaning liquid can be continuously replenished from the liquid outlet to the space between the liquid outlet and the receiving surface.

[0012] The apparatus described above for cleaning the edge of a silicon wafer may further include a first moving component, which allows the droplet supply component to move between a working position for cleaning the edge of the silicon wafer and a first cleaning position for cleaning the droplet supply component.

[0013] In the aforementioned apparatus for cleaning the edge of a silicon wafer, the vacuum device can be configured to adjust the vacuum level inside the droplet supply component to prevent droplets from falling before the droplet supply component reaches the first cleaning position and to allow the cleaning fluid to rinse the droplet supply component when the droplet supply component is in the first cleaning position.

[0014] In the aforementioned apparatus for cleaning the edge of a silicon wafer, the first moving component may include a guide rail and a slider. The slider is fixedly connected to the droplet supply component and slidably connected to the guide rail to move the droplet supply component between a working position and a first cleaning position.

[0015] The apparatus described above for cleaning the edge of a silicon wafer may further include a second moving component, which allows the receiving component to move between a working position for cleaning the edge of the silicon wafer and a second cleaning position for cleaning the receiving component.

[0016] The aforementioned apparatus for cleaning the edge of a silicon wafer may further include a receiving component cleaning device, which includes a cleaning fluid pipeline having an outlet located at a second cleaning position for rinsing the receiving component that has moved to the second cleaning position.

[0017] In the aforementioned apparatus for cleaning the edge of a silicon wafer, the second moving component may include a connecting rod, one end of which is fixedly connected to a receiving component, and the connecting rod is rotatable about its other end in a horizontal plane to move the receiving component between a working position and a second cleaning position.

[0018] In the aforementioned apparatus for cleaning the edges of silicon wafers, the connecting rod can be configured to be telescopic so that the receiving component can avoid interference with the edge clamping mechanism of the silicon wafer.

[0019] According to another aspect of this disclosure, a method for cleaning the edge of a silicon wafer is provided, the method being performed using an apparatus for cleaning the edge of a silicon wafer as described in any of the preceding paragraphs.

[0020] According to this disclosure, a certain amount of droplets is maintained by the combined effect of a weak vacuum and the surface tension of the droplets, and the edge of a rotating silicon wafer is inserted into the droplets to achieve cleaning of the wafer edge. Since the droplets are stationary when in contact with the edge of the silicon wafer, they can wet the entire area of ​​the wafer edge, thereby enabling a more thorough and effective cleaning of the wafer edge.

[0021] The above-described features and advantages, as well as other features and advantages, of this disclosure will become clearer from the following detailed description of exemplary embodiments of the disclosure in conjunction with the accompanying drawings. Attached Figure Description

[0022] Figure 1 A side view schematically illustrates an apparatus for cleaning the edge of a silicon wafer according to an embodiment of the present disclosure, wherein the apparatus is in an operating state for cleaning the edge of the silicon wafer.

[0023] Figure 2 A schematic top view is shown. Figure 1 The apparatus shown is used for cleaning the edges of silicon wafers;

[0024] Figure 3 The edge of a silicon wafer wetted by droplets of cleaning solution is shown schematically in a magnified view;

[0025] Figure 4 A side view schematically illustrates an apparatus for cleaning the edge of a silicon wafer according to an embodiment of the present disclosure, wherein the apparatus is in a cleaning state for cleaning a droplet supply component and a receiving component; and

[0026] Figure 5 A schematic top view is shown. Figure 4 The apparatus shown is used for cleaning the edges of silicon wafers. Detailed Implementation

[0027] The present disclosure will now be described in detail with reference to the accompanying drawings and exemplary embodiments. It should be noted that the following detailed description of the present disclosure is for illustrative purposes only and is not intended to limit the scope of the disclosure.

[0028] According to the embodiments of this disclosure, refer to Figure 1 and Figure 2 An apparatus 1 for cleaning the edges of a silicon wafer is provided, comprising:

[0029] The droplet supply component 10 has a downward-facing outlet 11 for supplying cleaning fluid;

[0030] The receiving component 20 is positioned below the outlet 11 during the cleaning operation and has a receiving surface 21 for receiving the cleaning fluid from the outlet 11; and

[0031] A vacuum device (not shown) is connected to the droplet supply component 10 to create a weak vacuum inside the droplet supply component 10, so that the droplets 12 of cleaning fluid from the outlet 11 can be held between the outlet 11 and the receiving surface 21 under the action of the weak vacuum and the surface tension generated at the receiving surface 21, so as to clean the edge of the silicon wafer 100 inserted between the outlet 11 and the receiving surface 21.

[0032] Specifically, in this disclosure, by setting up a vacuum device and a receiving component 20, the droplets 12 of cleaning fluid from the outlet 11 will be subjected to an upward force due to the internal and external pressure difference of the droplet supply component 10 under the action of a weak vacuum, and will be subjected to a downward force due to the surface tension caused by the contact between the droplets 12 and the receiving surface 21, thereby being relatively statically maintained and filled between the outlet 11 and the receiving surface 21.

[0033] When cleaning, such as Figure 3 As shown, a droplet 12 (schematically shown in a dashed box) is inserted from the side of the silicon wafer 100 between the liquid outlet 11 and the receiving surface 21. The droplet 12, which is held relatively still, wets the edge 101 of the silicon wafer 100. Under the action of surface tension caused by the contact between the droplet 12 and the edge 101 of the silicon wafer 100, the droplet 12 will at least partially wet the upper portion 101a and the lower portion 101b of the edge 101 and completely wet the side portion 101c of the edge 101 (these three portions are within...). Figure 3 (The area is schematically divided by two dashed lines). In this case, the silicon wafer 100 is rotated slowly (e.g., ...). Figure 2 and Figure 5 (As shown by the middle arrow), the edges of the silicon wafer 100 can be cleaned.

[0034] Because the droplets 12, which are maintained relatively still, are stationary when in contact with the edge of the silicon wafer 100, they can wet the entire area of ​​the edge 101 of the silicon wafer 100, unlike direct rinsing of the edge 101 where the cleaning fluid has a certain movement speed, making it prone to splashing and difficult to completely wet the entire edge. Therefore, the apparatus for cleaning silicon wafer edges disclosed herein can clean the silicon wafer edges more thoroughly and effectively.

[0035] Understandably, as the silicon wafer 100 rotates, the droplets 12 will be carried away from the area between the outlet 11 and the receiving surface 21 due to contact with the edge of the silicon wafer 100. The next clean droplet 12 from the cleaning fluid will be automatically replenished from the outlet 11 and maintained between the outlet 11 and the receiving surface 21. Thus, the area between the outlet 11 and the receiving surface 21 will be continuously filled with droplets 12, thereby achieving cleaning of the entire circumferential edge of the silicon wafer.

[0036] According to an embodiment of the present disclosure, the apparatus 1 may further include a liquid supply device, which includes a liquid supply line 30 communicating internally with the droplet supply member 10 for supplying cleaning liquid to the droplet supply member 10, such that as the edge of the silicon wafer 100 is cleaned, droplets 12 of cleaning liquid can be continuously replenished from the outlet 11 to the space between the outlet 11 and the receiving surface 21.

[0037] The liquid supply device can continuously supply cleaning fluid to the inside of the droplet supply component 10, so that the space between the liquid outlet 11 and the receiving surface 21 is always filled with droplets 12, thereby enabling the edge of the silicon wafer 100 to be continuously and smoothly cleaned effectively.

[0038] It is conceivable that the cleaning fluid can be supplied to the droplet supply component 10 in other ways. For example, a storage tank connected to the droplet supply component 10 can be provided with the cleaning fluid, or a certain amount of cleaning fluid can be pre-stored in the droplet supply component 10.

[0039] For example, in embodiments of this disclosure, the receiving component 20 may take the form of a receiving platform, and the receiving surface may be a receiving plane. Furthermore, the outlet 11 of the droplet supply component 10 may be circular, and the receiving surface may be correspondingly circular.

[0040] In embodiments of this disclosure, the vacuum device may include a vacuum line 40 communicating internally with the droplet supply component 10 to create a weak vacuum inside the droplet supply component 10. It is conceivable that the vacuum device may also take other forms that allow direct connection to the droplet supply component 10.

[0041] During the cleaning process of silicon wafer edges, contaminants on the wafer edges may adhere to the droplet supply component 10, particularly its outlet 11, and may also adhere to the bearing surface 21 of the carrier component 20, potentially contaminating the next silicon wafer to be cleaned. To avoid this cross-contamination, it is necessary to clean the droplet supply component 10 and the carrier component 20, particularly the outlet 11 and the bearing surface 21, depending on the actual contamination level, for example, after cleaning one or more silicon wafers.

[0042] Therefore, in embodiments of this disclosure, the device 1 may further include a first moving member 50, through which the droplet supply member 10 can be positioned (e.g., at a working position for cleaning the edge of the silicon wafer 100) via the first moving member 50. Figure 1 and Figure 2 (as shown) and the first cleaning position for cleaning the droplet supply component 10 (e.g.) Figure 4 and Figure 5 Move between (as shown) Figure 4 As indicated by the middle arrow.

[0043] By moving the droplet supply component 10 from the working position to the first cleaning position, the droplet supply component 10 is no longer aligned with the edge of the silicon wafer 100 in the vertical direction, thus allowing the droplet supply component 10, especially the outlet 11, to be cleaned without contaminating the edge and other parts of the silicon wafer 100.

[0044] It is conceivable that the droplet supply component 10, particularly the outlet 11, is cleaned by a cleaning fluid from the droplet supply component 10. In this case, the vacuum device can be configured to adjust the vacuum level inside the droplet supply component 10 to prevent the droplet 12 from dripping before the droplet supply component 10 reaches the first cleaning position and to allow the cleaning fluid to rinse the droplet supply component 10 when it is in the first cleaning position.

[0045] Specifically, during the process of the droplet supply component 10 moving from the working position to the first cleaning position, the vacuum device can slightly increase the vacuum level so that the droplet 12 does not drip. When the first cleaning position is reached, the vacuum device can decrease the vacuum level, for example, reduce it to zero, that is, release the vacuum, so as to allow the cleaning fluid to rinse the droplet supply component 10, especially the outlet 11.

[0046] It is conceivable that the liquid supply device can be configured to adjust the flow rate of the cleaning fluid it provides. Thus, when rinsing the droplet supply component 10, the flow rate of the cleaning fluid can be increased by the liquid supply device to improve the rinsing effect.

[0047] In embodiments of this disclosure, such as Figure 1 and Figure 2 as well as Figure 4 and Figure 5 As shown, the first moving component 50 may include a guide rail 501 and a slider 502. The slider 502 is fixedly connected to the droplet supply component 10 and slidably connected to the guide rail 501 to drive the droplet supply component 10 to move between the working position and the first cleaning position.

[0048] It is conceivable that the first cleaning position could be located as far away from the silicon wafer 100 as possible to avoid contaminants that might have been re-adhered to the silicon wafer 100 during the cleaning of the droplet supply component 10. For example, the working position could correspond to one end of the guide rail 501, while the first cleaning position could correspond to the other end of the guide rail 501.

[0049] like Figure 1 As shown, the droplet supply component 10 can be fixedly connected to the slider 502 via the fastener 13. In addition, the first moving component 50 may also include a vertical rod 503 fixedly connected to the machine base, and the guide rail 501 may be fixedly connected to the vertical rod 503.

[0050] It is conceivable that the first moving part 50 could also take any other known form.

[0051] In embodiments of this disclosure, the apparatus 1 may further include a second moving member 60, which enables the receiving member 20 to be positioned at a working position for cleaning the edge of the silicon wafer 100 (e.g., ...). Figure 1 and Figure 2 (as shown) and a second cleaning location for cleaning the receiving component 20 (as shown) Figure 4 and Figure 5 Move between (as shown in the image).

[0052] By moving the receiving component 20 from the working position to the second cleaning position, the receiving component 20 is no longer aligned with the edge of the silicon wafer 100 in the vertical direction, thus allowing the receiving component 20, especially the receiving surface 21, to be cleaned without contaminating the edges and other parts of the silicon wafer 100.

[0053] The receiving component 20 and the droplet supply component 10 can be moved simultaneously from the working position by the second moving component 60 and the first moving component 50, and then separated horizontally after they have moved to a certain distance from the edge of the silicon wafer 100 so that they can be rinsed separately.

[0054] In embodiments of this disclosure, device 1 may further include a component cleaning device, which includes a cleaning fluid line 70, such as... Figure 1 and Figure 2 as well as Figure 4 and Figure 5 As shown, the cleaning fluid line 70 has an outlet located at the second cleaning position for rinsing the receiving component 20, particularly the receiving surface 21, which has been moved to the second cleaning position.

[0055] It is conceivable that the receiving component cleaning device can be configured to adjust the flow rate of the cleaning fluid it provides. Thus, when rinsing the receiving component 20, the flow rate of the cleaning fluid can be increased by the receiving component cleaning device to improve the rinsing effect.

[0056] In embodiments of this disclosure, the second moving component 60 may include a connecting rod 61, one end of which is fixedly connected to the receiving component 20, and the connecting rod 61 is rotatable about its other end in a horizontal plane to drive the receiving component 20 to move between a working position and a second cleaning position.

[0057] like Figure 1 and Figure 2 as well as Figure 4 and Figure 5As shown, the other end of the connecting rod 61 can be rotatably connected to the vertical rod 503 to allow the connecting rod 61 to rotate about its other end in the horizontal plane.

[0058] It is conceivable that the second cleaning position could be located as far away from the silicon wafer 100 as possible to avoid contaminants that might have been transferred to the silicon wafer 100 during the cleaning of the receiving component 20. For example, the second cleaning position could correspond to the position reached by rotating the connecting rod 61 90° from its working position in the horizontal plane.

[0059] Furthermore, the connecting rod 61 can be configured to be telescopic so that the receiving component 20 can avoid interference with the edge clamping mechanism 200 of the silicon wafer 100.

[0060] Reference Figure 1 and Figure 2 During silicon wafer edge cleaning, the edge clamping mechanism 200, used to fix the silicon wafer 100 by clamping its edge, rotates as the silicon wafer 100 rotates. This can lead to interference between the edge clamping mechanism 200 and the receiving component 20 at the silicon wafer edge. By making the connecting rod 61 retractable, the receiving component 20 can avoid interference with the edge clamping mechanism 200 by retracting the connecting rod 61.

[0061] For example, a spring 62 may be provided inside the connecting rod 61 to achieve the telescopic function of the connecting rod 61. It is conceivable that this telescopic function may also be implemented in any other known form.

[0062] In the embodiments of this disclosure, a waste liquid collection box 80 can be provided at the first cleaning position and the second cleaning position, below the droplet supply component 10 and the receiving component 20, respectively, to collect the waste liquid generated when cleaning the droplet supply component 10 and the receiving component 20.

[0063] Furthermore, it is conceivable that the waste liquid collection box 80 can be connected to the equipment waste liquid discharge system for discharging the collected waste liquid.

[0064] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. An apparatus for cleaning the edges of silicon wafers, characterized in that, include: A droplet supply component having a downward-facing outlet for supplying cleaning fluid; A receiving component that can be arranged below the outlet during the cleaning operation and has a receiving surface for receiving the cleaning liquid from the outlet; as well as A vacuum device, connected to the droplet supply component, is used to create a weak vacuum inside the droplet supply component, such that droplets of the cleaning fluid from the outlet are held between the outlet and the receiving surface by the weak vacuum and the surface tension generated at the receiving surface. During the cleaning operation, the edge of the silicon wafer can be inserted from the side into the droplet held between the liquid outlet and the receiving surface, and the silicon wafer can rotate relative to the droplet supply component and the receiving component, so that the droplet cleans the entire circumferential edge of the silicon wafer.

2. The apparatus for cleaning the edges of silicon wafers according to claim 1, characterized in that, It also includes a liquid supply device, which includes a liquid supply line communicating internally with the droplet supply component for supplying the cleaning liquid to the droplet supply component, so that as the edge of the silicon wafer is cleaned, droplets of the cleaning liquid can be continuously replenished from the outlet to the space between the outlet and the receiving surface.

3. The apparatus for cleaning the edges of silicon wafers according to claim 1 or 2, characterized in that, It also includes a first moving component, which allows the droplet supply component to move between a working position for cleaning the edge of the silicon wafer and a first cleaning position for cleaning the droplet supply component.

4. The apparatus for cleaning the edge of a silicon wafer according to claim 3, characterized in that, The vacuum device is configured to adjust the vacuum level inside the droplet supply component to prevent the droplets from dripping before the droplet supply component reaches the first cleaning position and to allow the cleaning fluid to rinse the droplet supply component when the droplet supply component is in the first cleaning position.

5. The apparatus for cleaning the edges of a silicon wafer according to claim 3, characterized in that, The first moving component includes a guide rail and a slider. The slider is fixedly connected to the droplet supply component and slidably connected to the guide rail for moving the droplet supply component between the working position and the first cleaning position.

6. The apparatus for cleaning the edges of a silicon wafer according to claim 1 or 2, characterized in that, It also includes a second moving component, which allows the receiving component to move between a working position for cleaning the edge of the silicon wafer and a second cleaning position for cleaning the receiving component.

7. The apparatus for cleaning the edges of a silicon wafer according to claim 6, characterized in that, It also includes a receiving component cleaning device, which includes a cleaning fluid pipeline having an outlet located at the second cleaning position for rinsing the receiving component that has been moved to the second cleaning position.

8. The apparatus for cleaning the edge of a silicon wafer according to claim 6, characterized in that, The second moving component includes a connecting rod, one end of which is fixedly connected to the receiving component, and the connecting rod is rotatable about its other end in a horizontal plane to move the receiving component between the working position and the second cleaning position.

9. The apparatus for cleaning the edge of a silicon wafer according to claim 8, characterized in that, The connecting rod is designed to be retractable so that the receiving component can avoid interference with the edge clamping mechanism of the silicon wafer.

10. A method for cleaning the edges of a silicon wafer, characterized in that, The method is performed using an apparatus for cleaning the edges of a silicon wafer as described in any one of claims 1 to 9.

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