Wafer edge blocking structure

Abstract

The utility model provides a wafer edge blocking structure, which comprises two semicircular assemblies, two transverse telescopic assemblies and two longitudinal telescopic assemblies, and is characterized in that the two semicircular assemblies can be assembled to form a circular ring so as to fit and wrap the edge of a wafer, and each semicircular assembly comprises an upper baffle, a side baffle and a lower baffle which are connected in sequence; the two transverse telescopic assemblies are arranged on the outer sides of the side baffles of the two semicircular assemblies correspondingly so that the two semicircular assemblies can move relatively and transversely and can be assembled to form a circular ring. The two longitudinal telescopic assemblies are arranged on the bottom faces of the lower baffles of the two semicircular assemblies respectively so that the lower baffles can move longitudinally to be attached to the edge of the wafer. According to the utility model, pollution to the edge of the wafer and the machine table can be avoided, and the device is suitable for wafers with different thicknesses and has wide applicability.

Description

TECHNICAL FIELD

[0001] The utility model relates to a semiconductor technical field especially relates to a wafer edge blocking structure. BACKGROUND

[0002] In the preparation process of semiconductor devices, especially in the preparation process of metal gate, it is needed to remove the dummy gate after depositing the dielectric layer, and it is needed to polish before removing the dummy gate to planarize the surface of wafer. However, when epitaxially growing in the center area of wafer, it will also epitaxially grow in the edge area of wafer, and the epitaxially grown material includes SiGe and NiSi; when polishing, because the polishing rate of each area of wafer is different, the polishing rate of the edge area of wafer is faster, and then the exposure of SiGe and NiSi will appear in the edge area of wafer, and the exposure of metal will contaminate the chamber of other process machines.

[0003] Figure 1 It is a cross-sectional schematic view of the preparation process of semiconductor devices after forming epitaxial groove in the prior art. Please refer to Figure 1 , the epitaxial groove 30 is formed in the center area 10 and the edge area 20 of wafer, and the gate structure 40 is formed on the surface of wafer, and the gate structure 40 includes the dummy gate 42 and the dielectric layer covering the dummy gate 42.

[0004] Figure 2 It is a cross-sectional schematic view of the preparation process of semiconductor devices after forming epitaxial structure in the prior art. Please refer to Figure 2 , the epitaxial structure 32 is formed by epitaxial growth in the epitaxial groove, and the epitaxial structure 32 is located in the center area 10 and the edge area 20, and the epitaxially grown material generally includes SiGe and NiSi.

[0005] Figure 3 It is a cross-sectional schematic view of the preparation process of semiconductor devices after forming dielectric layer in the prior art. Please refer to Figure 3 , the dielectric layer 50 is deposited to cover the center area 10 and the edge area 20, and the dielectric layer 50 covers the gate structure 40, and in Figure 3 , the top surface of the dielectric layer 50 on the center area 10 and the edge area 20 is flush, and actually the top surface of the dielectric layer 50 on the gate structure 40 is higher than the top surface of the dielectric layer 50 on other positions.

[0006] Figure 4 It is a cross-sectional schematic view of the preparation process of semiconductor devices after executing the polishing process in the prior art. Please refer to Figure 4, the grinding medium layer 50 and the dielectric layer on the dummy gate 42 are ground to expose the dummy gate 42, however, due to the different grinding rates of the center area 10 and the edge area 20 of the wafer and the different grinding materials (the dummy gate 42 has the dielectric layer), the grinding rate of the edge area 20 of the wafer is greater than the grinding rate of the center area 10 of the wafer, thereby exposing the epitaxial structure 32 of the edge area 20 of the wafer, that is, the SiGe and NiSi are exposed in the edge area 20 of the wafer, the metal exposure pollutes the chamber of the machine in other processes, and pollutes the edge area 20 of the wafer. Utility model content

[0007] The utility model discloses a wafer edge blocking structure, avoid polluting wafer edge and machine, and be applicable to wafer of different thickness.

[0008] In order to reach above -mentioned purpose, the utility model provides a wafer edge blocking structure, include:

[0009] Two half circle components can be assembled to form a circular ring to fit and wrap the wafer edge, the half circle component includes the upper baffle, the side baffle and the lower baffle connected in turn;

[0010] Two lateral telescopic components are respectively arranged on the outer side of the side baffle of the two half circle components, so that the two half circle components can be assembled to form a circular ring by moving laterally;

[0011] Two longitudinal telescopic components are respectively arranged on the bottom surface of the lower baffle of the two half circle components, so that the lower baffle can be moved longitudinally to fit the wafer edge.

[0012] Optionally, the upper baffle and the side baffle are fixedly connected, and the side baffle and the lower baffle are movably connected.

[0013] Optionally, the upper baffle and the lower baffle are parallel, and the side baffle is inclined relative to the upper baffle and the lower baffle.

[0014] Optionally, the included angle between the side baffle and the lower baffle is less than 90 degrees.

[0015] Optionally, the width of the lower baffle is greater than the width of the upper baffle.

[0016] Optionally, the width of the upper baffle is 2mm-5mm.

[0017] Optionally, the lower baffle fits at least 2mm-5mm of the wafer edge.

[0018] Optionally, the material of the half circle component is ceramic.

[0019] Optionally, the assembling surface of the two half-circle assemblies is provided with buckles, and the buckles of the two half-circle assemblies are buckled when the two half-circle assemblies are assembled to form a ring.

[0020] Optionally, the longitudinal telescopic assembly comprises a supporting part, a telescopic part and a fixing part, the supporting part is connected with the bottom surface of the lower baffle, the telescopic part is located in the supporting part so that the lower baffle moves longitudinally, and the fixing part is located outside the supporting part and passes through the supporting part to fix the telescopic part.

[0021] In the utility model, two half-circle assemblies are relatively moved transversely to be assembled to form a ring to fit and wrap the wafer edge, the gas will not diffuse to the wafer edge during epitaxial growth, epitaxial growth on the wafer edge is prevented, pollution to the wafer edge and the machine table is avoided, and the wafer edge is protected. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a sectional view schematic diagram of a preparation process of a semiconductor device in the prior art after forming an epitaxial groove.

[0023] Figure 2 It is a sectional view schematic diagram of a preparation process of a semiconductor device in the prior art after forming an epitaxial structure.

[0024] Figure 3 It is a sectional view schematic diagram of a preparation process of a semiconductor device in the prior art after forming a dielectric layer.

[0025] Figure 4 It is a sectional view schematic diagram of a preparation process of a semiconductor device in the prior art after performing a grinding process.

[0026] Figure 5 It is a front view of the wafer edge blocking structure in an embodiment of the utility model when not assembled.

[0027] Figure 6 It is a top view of the wafer edge blocking structure in an embodiment of the utility model when not assembled.

[0028] Figure 7 This is a partial cross-sectional view of the wafer edge blocking structure provided in an embodiment of the present invention when it is not assembled.

[0029] Figure 8 This is a front view of the wafer edge blocking structure during assembly, as provided in an embodiment of the present invention.

[0030] Figure 9 This is a top view of the wafer edge blocking structure during assembly, as provided in an embodiment of the present invention.

[0031] Figure 10 This is a partial cross-sectional view of the wafer edge blocking structure provided in one embodiment of the present invention during assembly.

[0032] in, Figures 1-4 The attached figures are labeled as follows:

[0033] 10 - Central region; 20 - Edge region; 30 - Epitaxial groove; 32 - Epitaxial structure; 40 - Gate structure; 42 - Dummy gate; 50 - Dielectric layer;

[0034] Figures 5-10 The attached figures are labeled as follows:

[0035] 100 - Semicircular assembly; 110 - Upper baffle; 120 - Side baffle; 122 - Limiting part; 130 - Lower baffle; 200 - Lateral telescopic assembly; 300 - Longitudinal telescopic assembly; 310 - Support part; 320 - Telescopic part; 330 - Fixing part; 400 - Wafer. Detailed Implementation

[0036] The specific embodiments of this utility model will now be described in more detail with reference to the accompanying drawings. The advantages and features of this utility model will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this utility model.

[0037] Figure 5 This is a front view of the wafer edge blocking structure provided in this embodiment when it is not assembled. Figure 6 This is a top view of the wafer edge blocking structure provided in this embodiment when it is not assembled. Figure 7 This is a partial cross-sectional view of the wafer edge blocking structure provided in this embodiment when it is not assembled. Figure 8 This is a front view of the wafer edge blocking structure provided in this embodiment during assembly. Figure 9 This is a top view of the wafer edge blocking structure provided in this embodiment during assembly. Figure 10 This is a partial cross-sectional view of the wafer edge blocking structure provided in this embodiment during assembly; wherein Figure 6 for Figure 5 Top view,Figure 7 For Figure 6 A cross-sectional view along the direction of A1A2, Figure 9 For Figure 8 A top view, Figure 10 For Figure 9 A cross-sectional view along the direction of A1A2. Please refer to Figure 5 And Figure 6 The utility model provides a wafer edge blocking structure, include: two half circle subassembly 100, two transverse telescopic subassembly 200 and two longitudinal telescopic subassembly 300, wherein two half circle subassembly 100 can be assembled to form a circular ring to fit the edge of wafer 400 (such as Figure 9 Indicated).

[0038] In the embodiment, each half circle subassembly 100 includes upper baffle 110, side baffle 120 and lower baffle 130 connected in sequence, wherein the upper baffle 110 and the lower baffle 130 are parallel, the side baffle 120 is inclined relative to the upper baffle 110 and the lower baffle 130, specifically, the included angle θ1 between the side baffle 120 and the lower baffle 130 is less than 90 degrees, and the included angle θ2 between the side baffle 120 and the upper baffle 110 is greater than 90 degrees, in the embodiment, the side baffle 120 is arranged to be inclined relative to the upper baffle 110 and the lower baffle 130, the purpose is to prevent ions in the process from vertically reflecting on the side baffle 120 to pollute other areas, when the side baffle 120 is inclined relative to the upper baffle 110 and the lower baffle 130, the case that ions vertically reflect to pollute other areas can be reduced. In the embodiment, the included angle θ1 between the side baffle 120 and the lower baffle 130 is preferably 30 degrees to 75 degrees, for example, 30 degrees, 45 degrees, 60 degrees, and the included angle θ2 between the side baffle 120 and the upper baffle 110 can be known according to the included angle θ1 between the side baffle 120 and the lower baffle 130. In the embodiment, the material of the half circle subassembly 100 is preferably ceramic, that is, the materials of the upper baffle 110, the side baffle 120 and the lower baffle 130 are all ceramic, the ceramic material makes the surface of the half circle subassembly 100 smooth, and the surface of the half circle subassembly 100 will not grow during epitaxial growth, which is not limited to the above-mentioned material.

[0039] In the embodiment, the upper baffle 110 and the side baffle 120 are fixedly connected, and the upper baffle 110 and the side baffle 120 can be obtained by an integral molding process, or the upper baffle 110 and the side baffle 120 can be fixedly connected by other fixing modes. The side baffle 120 and the lower baffle 130 are movably connected, specifically, one end of the lower baffle 130 is movably connected to the inner side of the side baffle 120 (the inner side is the side of the side baffle 120 close to the wafer), and the movable contact surface of the side baffle 120 and the lower baffle 130 has no gap. In an example, a groove is formed on the inner side of the side baffle 120, the groove extends along the longitudinal direction of the inner side of the side baffle 120, the surface of the lower baffle 130 in contact with the side baffle 120 is provided with a protruding part, the protruding part and the groove are embedded, and the protruding part can move in the groove, so that the lower baffle 130 can move in the longitudinal direction, and the embedding of the protruding part and the groove can increase the tightness between the side baffle 120 and the lower baffle 130, which is not limited to the above example. In the embodiment, a limiting part 122 can be arranged on the inner side of the bottom of the side baffle 120, the limiting part 122 protrudes towards the inner side of the side baffle 120, and the limiting part 122 can prevent the lower baffle 130 from sliding out when it is not assembled; the width of the limiting part 122 is less than the width of the lower baffle 130, and each limiting part 122 of the side baffle 120 can be a semicircular ring (the same as the shape of the side baffle 120, which is a semicircular ring), or each side baffle 120 can have a plurality of limiting parts 122, and each limiting part 122 is a rectangular block.

[0040] Please refer to Figure 7 and Figure 10 In the embodiment, the width S2 of the lower baffle 130 is greater than the width S1 of the upper baffle 110, and the width S1 of the upper baffle 110 represents the width of the upper baffle 110 abutting the edge of the front surface of the wafer 400, and the front surface of the wafer 400 is the surface facing upwards in Figure 10 Figure 9 , Figure 9 In the embodiment, the front surface of the wafer 400 is shown in Figure 9 In order to clearly show that the upper baffle 110 abuts the edge of the front surface of the wafer 400, a certain transparency is provided for the upper baffle 110. In the embodiment, the width S1 of the upper baffle 110 can be 2mm-5mm, preferably 2.5mm-3mm; the lower baffle 130 abuts the edge of the back surface of the wafer 400 by 2mm-5mm, and the width of the lower baffle 130 abutting the edge of the back surface of the wafer 400 can be the same as the width S1 of the upper baffle 110, and the back surface of the wafer 400 is the surface facing downwards in Figure 10 The width of the lower baffle 130 is set, and the lower baffle 130 will move longitudinally, and with the longitudinal movement of the lower baffle 130, the width of the lower baffle 130 abutting the edge of the back surface of the wafer 400 will change, for example, in Figure 10 ​In the embodiment, when the lower baffle 130 moves upward gradually from bottom to top, the width of the lower baffle 130 adhering to the edge of the back surface of the wafer 400 gradually increases, and when the lower baffle 130 is in the lowest position (i.e., when the lower baffle 130 is in contact with the limiting portion 122), the width of the lower baffle 130 adhering to the edge of the back surface of the wafer 400 is the smallest (which can be the same as the width S1 of the upper baffle 110), Figure 10 In the embodiment, the width S3 of the lower baffle 130 adhering to the edge of the back surface of the wafer 400 is greater than the width of the upper baffle 110 adhering to the edge of the front surface of the wafer 400. In the embodiment, the maximum distance H between the upper baffle 110 and the lower baffle 130 represents the maximum thickness of the wafer to be used, and the maximum distance H between the upper baffle 110 and the lower baffle 130 can be 2 mm, but is not limited thereto.

[0041] In the embodiment, the assembling surface of each of the two half-round assemblies 100 is provided with a buckle. Figure 8 and Figure 9 In the embodiment, as shown in the oval virtual frame, the buckles of the two half-round assemblies 100 are buckled to connect the two half-round assemblies 100 when the two half-round assemblies 100 are assembled to form a circular ring. Specifically, the upper baffle 110, the side baffle 120, and / or the lower baffle 130 of the two half-round assemblies 100 are provided with buckles, so that the two half-round assemblies 100 can be connected, and there is no gap between the two half-round assemblies 100 after the connection.

[0042] Please refer to Figure 8 and Figure 9 The two lateral telescopic assemblies 200 are respectively arranged outside the side baffles 120 of the two half-round assemblies 100 (the outside is the side of the side baffles 120 away from the wafer 400), so that the two half-round assemblies 100 can be assembled to form a circular ring by moving laterally relative to each other. The specific structure of the lateral telescopic assembly 200 is not limited herein. In the embodiment, the two half-round assemblies 100 can be assembled to form a circular ring by moving laterally relative to each other to adhere to and wrap the edge of the wafer 400, so that the gas does not diffuse to the edge of the wafer 400 during epitaxial growth, preventing epitaxial growth on the edge of the wafer 400, thereby avoiding pollution to the edge of the wafer 400 and the machine table, so as to protect the edge of the wafer 400.

[0043] Please refer to Figure 5 and Figure 8 The two longitudinal telescopic assemblies 300 are respectively arranged on the bottom surfaces of the lower baffles 130 of the two half-round assemblies 100, so that the lower baffles 130 move longitudinally to adhere to the edge of the wafer 400; for example, in Figure 8In this embodiment, the longitudinal telescopic assembly 300 is adjusted according to the thickness of the wafer 400, so that the longitudinal telescopic assembly 300 moves upward to fit the edge of the wafer 400. In this embodiment, the longitudinal telescopic assembly 300 includes a support portion 310, a telescopic portion 320, and a fixing portion 330. The support portion 310 is connected to the bottom surface of the lower baffle 130. The telescopic portion 320 is located in the support portion 310 (the support portion 310 at least wraps the opposite sides of the telescopic portion 320). The telescopic portion 320 telescopes longitudinally in the support portion 320 to push the lower baffle 130 to move longitudinally. The fixing portion 330 is located outside the support portion 310 and passes through the support portion 310 to fix the telescopic portion 320. After the telescopic portion 320 stops moving, the telescopic portion 320 is fixed by the fixing portion 330 and no longer moves. At this time, the lower baffle 130 fits the edge of the back surface of the wafer 400, and the upper baffle 110 fits the edge of the front surface of the wafer 400. In this embodiment, the blocking structure can be applied to wafers 400 of different thicknesses and can fit the edge of the wafer 400 by setting the longitudinal telescopic assembly 300, and has wide applicability.

[0044] In this embodiment, when the blocking structure is not assembled, the state of the blocking structure is as shown in Figure 5 and Figure 6 Before the wafer enters the cavity of the machine, the blocking structure is assembled to the wafer. After the blocking structure is assembled, the state of the blocking structure is as shown in Figure 8 and Figure 9 The longitudinal telescopic assembly is adjusted according to the thickness of the wafer to fit the edge of the wafer, and has wide adaptability. After the blocking structure is assembled, the wafer with the blocking structure is sent to the cavity for a process flow. Since the blocking structure wraps and fits the edge of the wafer, the edge of the wafer will not be affected by the process and will not react. It can avoid epitaxial growth or other process flows on the edge of the wafer, thereby avoiding contamination of the edge of the wafer and the machine, to protect the edge of the wafer.

[0045] In conclusion, the wafer edge blocking structure provided in the utility model comprises two half-circle assemblies, two horizontal telescopic assemblies and two vertical telescopic assemblies, wherein the two half-circle assemblies can be assembled to form a circular ring to fit and wrap the wafer edge, the half-circle assembly comprises an upper baffle, a side baffle and a lower baffle which are connected in sequence; the two horizontal telescopic assemblies are arranged outside the side baffles of the two half-circle assemblies respectively, so that the two half-circle assemblies can be assembled to form a circular ring by moving horizontally relative to each other; and the two vertical telescopic assemblies are arranged on the bottom surfaces of the lower baffles of the two half-circle assemblies respectively, so that the lower baffles can move vertically to fit the wafer edge. In the utility model, the two half-circle assemblies can be assembled to form a circular ring by moving horizontally relative to each other to fit and wrap the wafer edge, so that the gas can not diffuse to the wafer edge during epitaxial growth, epitaxial growth on the wafer edge is prevented, pollution to the wafer edge and the machine table is avoided, and the wafer edge is protected; and the vertical telescopic assemblies are arranged on the bottom surfaces of the lower baffles, so that the blocking structure can be suitable for wafers with different thicknesses to fit the wafer edge, and the applicability is wide.

[0046] The above is only the preferred embodiment of the utility model, and does not limit the utility model in any way. Any person skilled in the art, without departing from the technical scheme of the utility model, can make any form of equivalent replacement or modification of the technical scheme and technical content disclosed in the utility model, and the change still belongs to the protection scope of the utility model.

Claims

1. A wafer edge barrier structure, comprising: The application relates to a wafer edge clamping device, which comprises two half-circle components capable of being assembled into a ring to fit and wrap the wafer edge, wherein the half-circle components comprise upper baffles, side baffles and lower baffles connected in sequence; two lateral telescopic components are arranged outside the side baffles of the two half-circle components to enable the two half-circle components to be assembled into a ring by moving laterally; two longitudinal telescopic components are arranged on the bottom surface of the lower baffles of the two half-circle components to enable the lower baffles to move longitudinally to fit the wafer edge. The upper baffles and the side baffles are fixedly connected, and the side baffles and the lower baffles are movably connected. The upper baffles and the lower baffles are parallel, and the side baffles are inclined relative to the upper baffles and the lower baffles. The included angle between the side baffles and the lower baffles is less than 90 degrees.

2. The wafer edge barrier structure of claim 1, wherein, The width of the lower baffles is greater than that of the upper baffles.

3. The wafer edge barrier structure of claim 1, wherein, The width of the upper baffles is 2-5 mm.

4. The wafer edge stop structure of claim 3, wherein, The lower baffles fit the wafer edge by 2-5 mm at least.

5. The wafer edge barrier structure of claim 1, wherein, The material of the half-circle components is ceramic.

6. The wafer edge barrier structure of claim 5, wherein, The assembling surfaces of the two half-circle components are provided with buckles, and the buckles of the two half-circle components are buckled when the two half-circle components are assembled into a ring.

7. The wafer edge barrier structure of claim 5, wherein, The longitudinal telescopic components comprise supporting parts, telescopic parts and fixing parts, the supporting parts are connected with the bottom surface of the lower baffles, the telescopic parts are located in the supporting parts to enable the lower baffles to move longitudinally, and the fixing parts are located outside the supporting parts and pass through the supporting parts to fix the telescopic parts.

8. The wafer edge barrier structure of claim 1, wherein, ​ 9. The wafer edge barrier structure of claim 1, wherein, ​ 10. The wafer edge barrier structure of claim 1, wherein, ​

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