Wafer edge covering mechanism and processing method of semiconductor device

Abstract

The invention provides a wafer edge covering mechanism and a processing method of a semiconductor device. The wafer edge covering mechanism comprises a fixing ring which is arranged on the edge of a heating disc and is provided with a plurality of fixing points; the shielding assembly comprises multiple sections of shadow rings and supporting rods with the corresponding number, and the multiple sections of shadow rings are rotationally connected with the corresponding fixing points through the corresponding supporting rods respectively; and the plurality of moving rods penetrate through the fixed ring to abut against the corresponding supporting rods and are used for driving the corresponding shadow rings and the supporting rods to rotate upwards by taking the corresponding fixed points as the axial direction so as to open the shielding assembly, or rotating downwards by taking the fixed points as the axial direction so as to close the shielding assembly so as to shield the edge of the wafer on the heating disc.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing, and in particular to a wafer edge shielding mechanism and a method for processing a semiconductor device. Background Art

[0002] In order to avoid thin film deposition on the edge of the wafer or the edge of the chamber, a shadow ring / edge ring is usually used in semiconductor process equipment to cover the edge of the wafer or the cavity. The current method for edge rings and shadow rings is mainly to support the edge ring / shadow ring by contacting the sawtooth ceramic ring surface after the heating plate moves to a certain position, or to position it through several contact points on the edge.

[0003] In the prior art, during the edge masking process, the wafer and the shadow ring are lifted and displaced, which easily causes the shadow ring to be displaced after the lifting movement, thereby causing poor edge masking repeatability or particle problems caused by contact collision between the wafer and the shadow ring.

[0004] In order to overcome the above-mentioned defects in the prior art, there is an urgent need in the art for a wafer edge masking technology for masking the wafer edge to overcome the poor repeatability of traditional shadow ring edge masking and the problem of edge contact particles. Summary of the invention

[0005] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or decisive elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0006] In order to overcome the above-mentioned defects in the prior art, the present invention provides a wafer edge shielding mechanism and a method for processing a semiconductor device, wherein a shadow ring shields the edge of the wafer by moving a moving rod up and down, so as to overcome the poor repeatability of traditional shadow ring edge shielding and the problem of edge contact particles.

[0007] Specifically, the wafer edge shielding mechanism provided according to the first aspect of the present invention includes: a fixed ring, which is arranged on the edge of the heating plate, wherein the fixed ring is provided with a plurality of fixed points; a shielding assembly, including a plurality of shadow rings and a corresponding number of support rods, wherein the plurality of shadow rings are respectively connected to the corresponding fixed points via the corresponding support rods in a rotational manner; and a plurality of movable rods, which pass through the fixed ring and abut against the corresponding support rods, and are used to drive the corresponding shadow rings and support rods to rotate upward with the corresponding fixed points as the axes to open the shielding assembly, or to rotate downward with each of the fixed points as the axes to close the shielding assembly to shield the edge of the wafer on the heating plate.

[0008] Furthermore, in some embodiments of the present invention, the wafer edge shielding mechanism further includes: a plurality of ejector pins passing through the heating plate to drive the wafer to rise or fall.

[0009] Furthermore, in some embodiments of the present invention, an interlocking structure is used between adjacent shadow rings to limit lateral displacement.

[0010] Furthermore, in some embodiments of the present invention, a spherical structure is provided at the top end of the moving rod, wherein the spherical structure is in sliding contact with the supporting rod to adjust the position of the shadow ring.

[0011] Furthermore, in some embodiments of the present invention, the spherical structure is made of aluminum oxide or aluminum nitride ceramics.

[0012] Furthermore, in some embodiments of the present invention, the wafer edge shielding mechanism also includes: a lifting pin support plate, which drives the moving rod to rise when it rises, so as to open the shielding assembly and drive the ejector to rise, and allows the moving rod and the ejector to descend when it descends.

[0013] Furthermore, in some embodiments of the present invention, the length of the moving rod is greater than the length of the ejector pin, so as to open the shielding assembly before lifting the ejector pin.

[0014] Furthermore, in some embodiments of the present invention, the wafer edge shielding mechanism also includes: a first weight, disposed at the lower end of the movable rod, for driving the movable rod to descend to a first target position in which the shielding assembly shields the edge of the wafer when the lifting ejector pin support plate descends, and / or a second weight, disposed at the lower end of the ejector pin, for driving the ejector pin to descend to a second target position in which the top end thereof does not exceed the surface of the heating plate when the lifting ejector pin support plate descends.

[0015] Furthermore, in some embodiments of the present invention, the wafer edge shielding mechanism further comprises: a plurality of gas guide grooves, provided on the upper surface and / or side surface of the fixing ring, for adjusting the flow resistance of the reaction gas on the wafer surface.

[0016] In addition, the processing method of the semiconductor device provided according to the second aspect of the present invention includes the following steps: in response to the need to place the wafer on the heating plate, lifting a plurality of movable rods of the wafer edge shielding mechanism as described in any one of the first aspects of the present invention to open the edge shielding component of the wafer edge shielding mechanism; placing the wafer on the heating plate; lowering the plurality of movable rods to close the shielding component and shield the edge of the wafer; and heating the wafer via the heating plate to process it.

[0017] Furthermore, in some embodiments of the present invention, the step of placing the wafer on the heating plate includes: placing the wafer on the top of a plurality of ejector pins passing through the heating plate; and synchronously lowering a lifting ejector pin support plate supporting the moving rod and the ejector pins to place the wafer on the heating plate, wherein the length of the moving rod is greater than the length of the ejector pins to close the shielding assembly after the wafer is placed on the heating plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0019] Figure 1 A front structural schematic diagram of a wafer edge shielding mechanism provided according to some embodiments of the present invention is shown.

[0020] Figure 2 A schematic side structural diagram of a wafer edge shielding mechanism provided according to some embodiments of the present invention is shown.

[0021] Figure 3 A schematic top view of a shadow ring assembly structure provided according to some embodiments of the present invention is shown.

[0022] Figure 4 A schematic structural diagram of a wafer edge shielding mechanism provided on a heating plate according to some embodiments of the present invention is shown.

[0023] Figure 5 A schematic structural diagram of the upper surface of a fixing ring provided according to some embodiments of the present invention is shown.

[0024] Figure 6 A schematic diagram of the shape of the guide groove provided according to some embodiments of the present invention is shown.

[0025] Figure 7 A schematic flow chart of a method for processing a semiconductor device according to some embodiments of the present invention is shown.

[0026] Figure 8 A schematic structural diagram of a wafer edge shielding mechanism for raising a heating plate provided in accordance with some embodiments of the present invention is shown.

[0027] Fig. 9 A schematic structural diagram of a wafer edge shielding mechanism for lowering a heating plate provided according to some embodiments of the present invention is shown.

[0028] Reference numerals:

[0029] 10 Heating plate

[0030] 11 Wafer

[0031] 20 Fixing ring

[0032] 21 Fixed point

[0033] 22 Gas diversion groove

[0034] 30 Occlusion Components

[0035] 31 Shadow Ring

[0036] 32 Support rod

[0037] 33 Support rod moving slot

[0038] 40 Moving Rod

[0039] 41 Ball

[0040] 42 The First Hammer

[0041] 50 Ejector pin

[0042] 51 The Second Hammer

[0043] 60 Lifting ejector support plate DETAILED DESCRIPTION

[0044] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0047] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0048] As mentioned above, in order to avoid thin film deposition on the edge of the wafer or the edge of the chamber, a shadow ring / edge ring is usually used in semiconductor process equipment to cover the edge of the wafer or the edge of the chamber. The current method for the edge ring and shadow ring is mainly to support the edge ring / shadow ring by contacting the sawtooth ceramic ring surface after the heating plate moves to a certain position, or to position it through several contact points on the edge.

[0049] In the prior art, during the edge masking process, the wafer and the shadow ring are lifted and displaced, which easily causes the shadow ring to be displaced after the lifting movement, thereby causing problems such as poor edge masking repeatability or edge contact particles.

[0050] In order to overcome the above-mentioned defects in the prior art, the present invention provides a wafer edge shielding mechanism and a method for processing a semiconductor device, wherein a shadow ring shields the edge of the wafer by moving a moving rod up and down to overcome the poor repeatability of traditional shadow rings and the problem of edge contact particles.

[0051] In some non-limiting embodiments, the processing method of the semiconductor device provided in the second aspect of the present invention can be implemented based on the wafer edge shielding mechanism provided in the first aspect of the present invention.

[0052] Please refer to Figure 1 to Figure 3 , Figure 1 A front structural schematic diagram of a wafer edge shielding mechanism provided according to some embodiments of the present invention is shown. Figure 2 A schematic side structural diagram of a wafer edge shielding mechanism provided according to some embodiments of the present invention is shown. Figure 3 A schematic top view of a shadow ring assembly structure provided according to some embodiments of the present invention is shown.

[0053] like Figure 1As shown, the wafer edge shielding mechanism includes a fixing ring 20 , a shielding assembly 30 and a plurality of moving rods 40 .

[0054] The fixing ring 20 is arranged at the edge of the heating plate 10, wherein a plurality of fixing points 21 are arranged on the fixing ring 20. The fixing ring 20 can be detachably arranged at the edge of the heating plate 10 in a snap-fit ​​manner. Therefore, the fixing ring 20 can simply and stably carry the shielding assembly 30 of the wafer shielding mechanism.

[0055] like Figure 2-3 As shown, the shielding assembly 30 includes a plurality of shadow rings 31 and a corresponding number of support rods 32. The plurality of shadow rings 31 (e.g., 4 segments) are rotatably connected to corresponding fixed points 21 via corresponding support rods 32, so that the shielding part rotates through the fixed points 21 to open and close, thereby avoiding the lifting operation of the shadow ring 31, and overcoming the problem of poor repeatability of the conventional shadow ring 31.

[0056] Furthermore, an interlocking structure (eg, L-shaped structure and / or reverse L-shaped structure) is used between adjacent shadow rings 31 to limit lateral displacement, so that multiple shadow ring segments can be assembled into a whole circular ring after falling, thereby improving the stability of the overall structure of the shielding portion.

[0057] Please continue to refer to Figure 1 The plurality of moving rods 40 pass through the fixing ring 20 and abut against the corresponding support rods 32, and are used to drive the corresponding shadow ring 31 and the support rods 32 to rotate upward with the corresponding fixed point 21 as the axis to open the shielding assembly 30, or rotate downward with each fixed point 21 as the axis to close the shielding assembly 30 to shield the edge of the wafer 11 on the heating plate 10. Here, the support rod 32 moves in the support rod 32 moving groove 33 provided in the fixing ring 20 to limit the protection thereof.

[0058] In some embodiments, the inner diameter of the shadow ring 31 may be 290 mm to 330 mm.

[0059] In some embodiments, a spherical ball 41 structure is provided at the top of the movable rod 40, wherein the spherical ball 41 structure is in sliding contact with the support rod 32 to adjust the position of the shadow ring 31, thereby effectively reducing the contact area between the support rod 32 and the ceramic spherical ball 41, reducing the degree of friction between the two, and thereby reducing particle contamination.

[0060] In some embodiments, the ball 41 is made of alumina or aluminum nitride ceramics to avoid particle contamination caused by sliding contact.

[0061] Please refer to Figure 4 , Figure 4 A schematic structural diagram of a wafer edge shielding mechanism provided on a heating plate according to some embodiments of the present invention is shown.

[0062] like Figure 4 As shown, the wafer edge shielding mechanism further includes a plurality of ejector pins 50 and an ejector pin lifting support plate 60 .

[0063] In some embodiments, the plurality of ejector pins 50 pass through the heating plate 10 to drive the wafer 11 to rise or fall. Furthermore, the wafer shielding mechanism can also be configured with a robot for taking and delivering the wafer 11. The rise of the ejector pins 50 drives the moving rod 40 to move up to lift the support rod 32, thereby driving the shadow ring 31 to move up, so that the robot can take and deliver the wafer 11.

[0064] The lifting pin support plate 60 drives the moving rod 40 to rise when rising, so as to open the shielding assembly 30 and drive the pin 50 to rise, and allows the moving rod 40 and the pin 50 to fall when falling.

[0065] In some semiconductor device processing devices, an ejector support plate may be configured. Therefore, the original ejector support plate may be expanded to support the moving rod 40, and the ejector support plate may serve as the lifting ejector support plate 60, and simultaneously support the moving rod 40 and the ejector 50 for lifting and moving. Therefore, the structure is simple and the operation is convenient. Here, the length of the moving rod 40 may be greater than the length of the ejector 50, so that the shielding assembly 30 is opened before the ejector 50 is lifted.

[0066] In some semiconductor device processing devices, the ejector pin 50 can be independently moved actively, so no ejector pin support plate is provided. Therefore, the lifting ejector pin support plate 60 can be set as a ring structure, which only supports the moving rod 40 to move up and down, thereby adjusting the positions of the moving rod 40 and the ejector pin 50 respectively, so that the adjustment action is more precise.

[0067] In addition, the wafer edge shielding mechanism further includes a first weight 42 and a second weight 51. The first weight 42 is disposed at the lower end of the moving rod 40, and is used to drive the moving rod 40 to descend to a first target position where the shielding assembly 30 shields the edge of the wafer 11 when the lifting ejector pin support plate 60 descends. The second weight 51 is disposed at the lower end of the ejector pin 50, and is used to drive the ejector pin 50 to descend to a second target position where its top does not exceed the surface of the heating plate 10 when the lifting ejector pin support plate 60 descends.

[0068] Please refer to Figure 2 and Figure 5-6 , Figure 5 A schematic structural diagram of the upper surface of a fixing ring provided according to some embodiments of the present invention is shown. Figure 6 A schematic diagram of the shape of the guide groove provided according to some embodiments of the present invention is shown.

[0069] like Figure 2 and Figure 5-6As shown, the wafer shielding mechanism also includes a plurality of gas guide grooves 22, which are arranged on the upper surface and / or side of the fixing ring 20, and are used to adjust the flow resistance of the reaction gas on the surface of the wafer 11 to improve the uniformity of the thickness of the deposited film layer. Here, the shape of the guide groove is rectangular, trapezoidal or S-shaped.

[0070] The working principle of the above-mentioned wafer edge shielding mechanism will be described below in conjunction with some embodiments of the processing method of semiconductor devices. Those skilled in the art will understand that the embodiments of the processing method of these semiconductor devices are only some non-limiting implementation methods provided by the present invention, which are intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit all functions or all working modes of the wafer edge shielding mechanism. Similarly, the wafer edge shielding mechanism is also only some non-limiting implementation methods provided by the present invention, and does not constitute a limitation on the execution subject or execution order of each step in the processing method of these semiconductor devices.

[0071] Please refer to Figure 7 to Figure 9 , Figure 7 A schematic flow chart of a method for processing a semiconductor device according to some embodiments of the present invention is shown. Figure 8 A schematic structural diagram of a wafer edge shielding mechanism for raising a heating plate provided in accordance with some embodiments of the present invention is shown. Fig. 9 A schematic structural diagram of a wafer edge shielding mechanism for descending a heating plate provided in accordance with some embodiments of the present invention is shown.

[0072] like Figure 7 As shown, the processing method of the semiconductor device first responds to the requirement of placing the wafer 11 on the heating plate 10, and lifts a plurality of moving rods 40 of the wafer edge shielding mechanism to open the edge shielding components of the wafer edge shielding mechanism.

[0073] like Figure 8 As shown, before the wafer 11 is sent into the reaction chamber, the lifting pin support plate 60 rises to drive the moving rod 40 to move upward, lift the support rod 32, and drive the shadow ring 31 to move upward, providing space for the robot to take and send the wafer 11. When the lifting pin support plate 60 continues to rise, it drives the moving rod 40 and the ejector 50 to rise, and the ejector 50 lifts the wafer 11 upward. At the same time, the shadow ring 31 continues to open, providing sufficient space for the vacuum robot to take the wafer 11.

[0074] After that, the wafer 11 is placed on the heating plate 10. Specifically, the method may be to place the wafer 11 on the top of a plurality of ejector pins 50 passing through the heating plate 10. Then, the lifting ejector pin support plate 60 supporting the moving rod 40 and the ejector pins 50 is synchronously lowered to place the wafer 11 on the heating plate 10. Here, the length of the moving rod 40 is greater than the length of the ejector pins 50, so that the shielding assembly 30 is closed after the wafer 11 is placed on the heating plate 10.

[0075] Afterwards, the plurality of movable rods 40 are lowered to close the shielding assembly 30 and shield the edge of the wafer 11 .

[0076] like Fig. 9 As shown, after the wafer 11 is delivered into the reaction chamber, the wafer 11 falls onto the ejector pin 50, and the lifting ejector pin support plate 60 descends. Based on the action of gravity, the moving rod 40 moves downward, driving the shadow ring 31 to move downward, and the shielding assembly 30 (for example: at 1 / 2 or 2 / 3 of the length) falls on the fixed ring 20, so that the shadow ring 31 shields the edge of the wafer 11.

[0077] In some embodiments, the method can also control the descending speed of the shadow ring 31 by controlling the descending speed of the lifting pin support plate 60 to avoid particle contamination caused by the shadow ring 31 directly hitting the surface of the wafer 11.

[0078] Finally, the wafer 11 is heated by the heating plate 10 to be processed.

[0079] In addition, the shadow ring 31 in the present application can change its working mode according to the requirements of the process. When its inner diameter is larger than the preset first diameter (for example, 300 mm), it can be kept in a closed state only by the fixed point and the device structure of the shadow ring, so that the plasma field can be changed without adjusting other device structures to improve the uniformity of thin film deposition.

[0080] In this scenario, the arc lengths of the shadow rings 31 can be set inconsistently to match the asymmetric design scenario in the cavity, and the uniformity thereof can be adjusted to further improve the uniformity of thin film deposition.

[0081] In summary, the wafer edge shielding mechanism and semiconductor device processing method provided by the present invention can shield the wafer edge by moving the shadow ring up and down through the moving rod, so as to overcome the problems of poor repeatability of the traditional shadow ring and edge contact particles.

[0082] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0083] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wafer edge shielding mechanism, characterized in that: include: A fixing ring is arranged on the edge of the heating plate, wherein the fixing ring is provided with a plurality of fixing points; A shielding assembly, comprising a plurality of shadow rings and a corresponding number of support rods, wherein the plurality of shadow rings are rotatably connected to corresponding fixed points via corresponding support rods; and A plurality of movable rods pass through the fixed ring and abut against the corresponding support rods, and are used to drive the corresponding shadow ring and the support rod to rotate upward with the corresponding fixed point as the axis to open the shielding assembly, or to rotate downward with each fixed point as the axis to close the shielding assembly to shield the edge of the wafer on the heating plate.

2. The wafer edge shielding mechanism according to claim 1, characterized in that: Also includes: A plurality of ejector pins pass through the heating plate to drive the wafer to rise or fall.

3. The wafer edge shielding mechanism according to claim 2, characterized in that: An interlocking structure is used between adjacent shadow rings to limit lateral displacement.

4. The wafer edge shielding mechanism according to claim 1, characterized in that: A spherical structure is provided at the top end of the moving rod, wherein the spherical structure is in sliding contact with the supporting rod to adjust the position of the shadow ring.

5. The wafer edge shielding mechanism according to claim 4, characterized in that: The spherical structure is made of aluminum oxide or aluminum nitride ceramics.

6. The wafer edge shielding mechanism according to claim 2, characterized in that: Also includes: The lifting pin support plate drives the moving rod to rise when it rises, so as to open the shielding assembly and drive the pin to rise, and allows the moving rod and the pin to fall when it falls.

7. The wafer edge shielding mechanism according to claim 6, characterized in that: The length of the moving rod is greater than the length of the ejector pin, so as to open the shielding assembly before lifting the ejector pin.

8. The wafer edge shielding mechanism according to claim 6, characterized in that: Also includes: a first weight, disposed at the lower end of the moving rod, for driving the moving rod to descend to a first target position where the shielding assembly shields the edge of the wafer when the lifting pin support plate descends, and / or The second weight is disposed at the lower end of the ejector pin, and is used to drive the ejector pin to descend to a second target position where its top end does not exceed the surface of the heating plate when the ejector pin lifting support plate descends.

9. The wafer edge shielding mechanism according to claim 1, characterized in that: Also includes: A plurality of gas guide grooves are arranged on the upper surface and / or the side surface of the fixing ring and are used to adjust the flow resistance of the reaction gas on the surface of the wafer.

10. A method for processing a semiconductor device, characterized in that: The following steps are involved: In response to a requirement to place a wafer on a heating plate, a plurality of moving rods of a wafer edge shielding mechanism according to any one of claims 1 to 9 are lifted to open an edge shielding component of the wafer edge shielding mechanism; placing the wafer on the heating plate; Lowering the plurality of movable rods to close the shielding assembly and shield the edge of the wafer; as well as The wafer is heated via the heating plate to process the wafer.

11. The processing method according to claim 10, characterized in that: The step of placing the wafer on the heating plate comprises: placing the wafer on top of a plurality of ejector pins passing through the heating plate; and The lifting pin support plate supporting the moving rod and the ejector pin is lowered synchronously to place the wafer on the heating plate, wherein the length of the moving rod is greater than the length of the ejector pin, so that the shielding assembly is closed after the wafer is placed on the heating plate.

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