Wafer bonding measuring device

Abstract

The utility model provides a wafer bonding measuring device. The wafer bonding measuring device comprises a bottom plate, a mobile control device, a chuck table, a chuck, a supporting ejector pin, a light source emitting device and a light source receiving device, the chuck table is of an annular structure, and at least three first connecting parts are arranged on the outer edge of the annular structure. The chuck is of a light-transmitting disc structure with the same area as the chuck table, a second connecting part corresponding to the first connecting part is arranged on the outer edge of the chuck, and the chuck is fixedly connected to the chuck table through the second connecting part and the first connecting part. During measurement, the stability of the chuck for supporting the wafer can be ensured, and the chuck does not shield light rays which are emitted by the light source emitting device above the wafer and penetrate through the wafer, so that the light rays are not prevented from being received by the light source receiving device, and a view blind area of the light source receiving device is avoided; therefore, the measuring device can measure all mark points on the wafer, so that the integrity of a measuring result is guaranteed, and the yield of the wafer is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a wafer bonding measurement device. Background Art

[0002] Wafer bonding is a key process in chip manufacturing, which involves tightly connecting two wafers together. After wafer bonding is completed, an optical lens is used to detect the degree of alignment of multiple marking points on the two connected wafers to determine the offset between the wafers. The closer to the edge of the wafer, the longer the arc length, and therefore the greater the offset. If bubbles exist between the wafers, the bubble area is the main cause of excessive offset, so as to ensure that as many marking points as possible are set on the wafer. However, existing optical lenses have blind spots during detection and fail to measure all marking points, thus affecting the integrity of the measurement results. If bubbles exist in the blind spot area of the wafer, it will directly affect the wafer yield. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a wafer bonding measurement device for measuring the offset of the marking points after two wafers with marking points are bonded; the device includes a base plate, a movement control device, a chuck table, a chuck, a supporting ejector pin, a light source emitting device and a light source receiving device;

[0004] The bottom plate and the supporting ejector are sequentially arranged from top to bottom below the light source emitting device;

[0005] A circular hole is provided in the center of the bottom plate, and the light source receiving device is provided in the circular hole; the movement control device is provided on the upper surface of the bottom plate, and the movement control device is connected to the chuck stage to drive the chuck stage to move on the bottom plate;

[0006] The chuck table is an annular structure with a circle of air holes at the bottom. At least three first connecting parts are provided on the outer edge of the annular structure. The chuck is a light-transmitting disk structure with the same area as the chuck table. A second connecting part corresponding to the first connecting part is provided on the outer edge of the chuck. The chuck is connected to the first connecting part and fixed to the chuck table via the second connecting part. A first through-hole corresponding to the supporting ejector pin is provided at the center of the chuck. The bottom plate is provided with a wafer loading area, and the wafer loading area is provided with a second through-hole corresponding to the supporting ejector pin.

[0007] When in working state, the movement control device drives the chuck stage to move to the wafer loading area on the base plate, the first through hole is aligned with the second through hole, the support pin rises and passes through the second through hole and the first through hole to receive the wafer and place it on the chuck, and the movement control device drives the chuck stage to the light source receiving device, the light source emitting device emits light through the wafer, and the light source receiving device receives the emitted light.

[0008] Optionally, the movement control device includes an X-axis driving device, an X-axis moving guide rail, a Y-axis driving device and a Y-axis moving guide rail, the X-axis moving guide rail is arranged on the base plate along the X-axis, and is driven by the X-axis driving device to move the chuck table along the X-axis moving guide rail; the Y-axis moving guide rail is arranged on the base plate along the Y-axis, and is driven by the Y-axis driving device to move the chuck table along the Y-axis moving guide rail.

[0009] Optionally, the circle of air holes includes a plurality of air flotation holes, and air is blown onto the base plate through the plurality of air flotation holes, so that the chuck table floats from the base plate.

[0010] Optionally, the circle of air holes includes a plurality of vacuum adsorption holes, and the chuck table is fixed on the base plate by evacuating a plurality of the vacuum adsorption holes.

[0011] Optionally, the first connecting component and the second connecting portion are connected and fixed by threaded fasteners.

[0012] Optionally, the translucent disk structure includes a wafer carrying area and an edge limiting area, wherein the edge limiting area is arranged around the wafer carrying area and is higher than the wafer carrying area. When the wafer is carried on the wafer carrying area, the edge limiting area limits the wafer from sliding on the wafer carrying area.

[0013] Optionally, the first through hole is opened at the center of the wafer supporting area, and the second connecting component is arranged outside the edge limiting area.

[0014] Optionally, the light-transmitting disk structure is made of quartz glass.

[0015] Optionally, the light source emitting device is an infrared light source emitting device.

[0016] Optionally, the light source receiving device is a transmissive infrared lens.

[0017] Compared with the prior art, the technical solution of the embodiment of the utility model has the following beneficial effects:

[0018] In the present invention, the chuck used to support the wafer in the wafer bonding measurement device is a translucent disk structure. Therefore, during measurement, the stability of the chuck supporting the wafer can be guaranteed, and at the same time, it will not block the light emitted by the light source emitting device above the wafer and passing through the wafer, and thus will not block the light source receiving device from receiving the light, thereby avoiding the blind spot of the light source receiving device, so that the measurement device can measure all the marking points on the wafer, thereby ensuring the integrity of the measurement results and improving the yield of the wafer.

[0019] Furthermore, in order to fix the position of the wafer and prevent the wafer from moving on the chuck, the translucent disk structure of the chuck includes a wafer carrying area and an edge limiting area. The edge limiting area is arranged around the wafer carrying area and is higher than the wafer carrying area. When the wafer is carried on the wafer carrying area, the edge limiting area limits the wafer from sliding on the wafer carrying area. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 This is a schematic structural diagram of a wafer bonding measurement device provided by an embodiment of the present invention;

[0022] Figure 2 This is a front structural schematic diagram of a chuck table provided in one embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of the bottom structure of a chuck table provided in one embodiment of the present utility model;

[0024] Figure 4 It is a plan view of a chuck provided in one embodiment of the utility model;

[0025] Figure 5 This is a three-dimensional diagram of a chuck provided in one embodiment of the present utility model;

[0026] Figure 6 yes Figure 5 Enlarged view of point A in the middle;

[0027] Description of reference numerals:

[0028] 1--Light source emitting device;

[0029] 2--base plate;

[0030] 3--Y-axis moving guide rail;

[0031] 4--Chuck table;

[0032] 401--first connecting component;

[0033] 4011--first threaded hole;

[0034] 5--Light source receiving device;

[0035] 6--Supporting thimble;

[0036] 7--Second through hole;

[0037] 8--X-axis moving guide rail;

[0038] 9--chuck;

[0039] 901--Second connecting member;

[0040] 9011--Second threaded hole;

[0041] 902--First through hole;

[0042] 903--Edge limit area;

[0043] 904--Wafer carrying area. DETAILED DESCRIPTION

[0044] As mentioned in the background, existing optical lens inspections have blind spots, which prevent them from measuring all the markings, thus affecting the integrity of the measurement results. If bubbles are present in the blind spots, the wafer yield will be directly affected.

[0045] Specifically, in existing wafer bonding measurement equipment, a metal bracket is used to support the wafers. This metal bracket includes a circular ring and a cross-shaped frame, with the cross-shaped frame fixed within the circular ring. During measurement, a pair of bonded wafers are placed on this metal bracket. Light emitted by a light source passes through the wafers to the optical lens. Because the cross-shaped frame is made of metal and is opaque, the optical lens has a blind spot in its field of view, affecting the integrity of the measurement results. If bubbles are present in the blind spot of the optical lens, the wafer yield will be directly affected.

[0046] To solve the above problems, the present invention provides a wafer bonding measurement device for measuring the offset of the marked points after two wafers with marked points are bonded. The device includes a base plate, a movement control device, a chuck table, a chuck, a support pin, a light source emitting device, and a light source receiving device.

[0047] The bottom plate and the supporting ejector are sequentially arranged from top to bottom below the light source emitting device;

[0048] A circular hole is provided in the center of the bottom plate, and the light source receiving device is provided in the circular hole; the movement control device is provided on the upper surface of the bottom plate, and the movement control device is connected to the chuck stage to drive the chuck stage to move on the bottom plate;

[0049] The chuck table is an annular structure with a circle of air holes at the bottom. At least three first connecting parts are provided on the outer edge of the annular structure. The chuck is a light-transmitting disk structure with the same area as the chuck table. A second connecting part corresponding to the first connecting part is provided on the outer edge of the chuck. The chuck is connected to the first connecting part and fixed to the chuck table via the second connecting part. A first through-hole corresponding to the supporting ejector pin is provided at the center of the chuck. The bottom plate is provided with a wafer loading area, and the wafer loading area is provided with a second through-hole corresponding to the supporting ejector pin.

[0050] When in working state, the movement control device drives the chuck stage to move to the wafer loading area on the base plate, the first through hole is aligned with the second through hole, the support pin rises and passes through the second through hole and the first through hole to receive the wafer and place it on the chuck, and the movement control device drives the chuck stage to the light source receiving device, the light source emitting device emits light through the wafer, and the light source receiving device receives the emitted light.

[0051] In the present invention, the chuck for supporting the wafer is a translucent disk structure. On the one hand, compared with the bracket in the prior art, when the wafer is placed on the chuck, the contact area between the wafer and the chuck becomes larger, which can ensure the support stability; on the other hand, since the chuck is made of a translucent material, during measurement, the chuck will not block the light emitted by the light source emitting device above the wafer and passing through the wafer, and will not block the light source receiving device from receiving the light, thereby avoiding the blind spot of the light source receiving device, so that the measuring device can measure all the marking points on the wafer, thereby ensuring the integrity of the measurement results and improving the yield of the wafer.

[0052] In order to make the above-mentioned purposes, features and beneficial effects of the present invention more clearly understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0053] Please refer to Figures 1 to 6One embodiment of the present invention provides a wafer bonding measurement device for measuring the offset of marked points after bonding two wafers with marked points. The device includes a base plate 2, a motion control device, a chuck table 4, a chuck 9, support pins 6, a light source emitting device 1, and a light source receiving device 5.

[0054] A circular hole is provided in the center of the base plate 2, and a light receiving device 5 is horizontally disposed within the hole. The light emitting device 1 is disposed above the base plate 2 and directly opposite the light receiving device 5. The present invention does not limit the specific types of the light emitting device 1 and the light receiving device 5; as long as the light emitting device 1 can emit light and the light receiving device 5 can receive the light emitted by the light emitting device 1, it can be sufficient. For example, the light emitting device 1 can be an infrared light emitting device 1, and the light receiving device 5 can be a transmissive infrared lens.

[0055] The movement control device is arranged on the upper surface of the base plate 2 and is connected to the chuck stage 4 , and is used for driving the chuck stage 4 to move on the base plate 2 .

[0056] The mobile control device is a mature technical means in this field. Therefore, the present invention does not limit the specific structure of the mobile control device, as long as it can drive the chuck table 4 to move on the base plate 2.

[0057] As an embodiment, the movement control device includes an X-axis driving device, an X-axis moving guide rail 8, a Y-axis driving device and a Y-axis moving guide rail 3. The X-axis moving guide rail 8 is arranged on the base plate 2 along the X-axis, and is driven by the X-axis driving device to move the chuck table 4 along the X-axis moving guide rail 8; the Y-axis moving guide rail 3 is arranged on the base plate 2 along the Y-axis, and is driven by the Y-axis driving device to move the chuck table 4 along the Y-axis moving guide rail 3.

[0058] The chuck table 4 is used to carry the chuck 9. As an embodiment, please refer to Figure 2 The chuck table 4 is an annular structure, and at least three first connecting parts 401 are provided on the outer edge of the annular structure. The chuck 9 is a light-transmitting disk structure with the same area as the chuck table 4. Please refer to Figure 4 A second connecting component 901 corresponding to the first connecting component 401 is provided on the outer edge of the chuck 9 , and the chuck 9 is connected and fixed to the chuck table 4 via the second connecting component 901 and the first connecting component 401 .

[0059] The present invention does not impose any specific restrictions on the connection method between the first connecting component 401 and the second connecting component 901. It can be a detachable fixed connection method or a non-detachable fixed connection method. In order to facilitate the replacement of the chuck 9, it is preferred that the first connecting component 401 and the second connecting component 901 are detachably fixedly connected, such as by snap-fitting, threaded fastening, etc. As an embodiment, a first threaded hole 4011 is provided on the first connecting component 401, and a second threaded hole 9011 corresponding to the first threaded hole 4011 is provided on the second connecting component 901. The first threaded hole 4011 and the second threaded hole 9011 are screwed into a threaded fastener such as a screw to achieve a threaded fastening connection between the first connecting component 401 and the second connecting component 901, thereby fixing the chuck 9 on the chuck table 4.

[0060] The base plate 2 is provided with a wafer loading area, and the supporting ejector pin 6 is located below the wafer loading area. The center of the chuck 9 is provided with a first through hole 902 corresponding to the supporting ejector pin 6, and the wafer loading area is provided with a second through hole 7 corresponding to the supporting ejector pin 6. In the working state, the movement control device drives the chuck table 4 to move to the wafer loading area on the base plate 2, the first through hole 902 is aligned with the second through hole 7, the supporting ejector pin 6 rises and passes through the second through hole 7 and the first through hole 902 in sequence to receive the wafer, and then the supporting ejector pin 6 descends with the wafer to place the wafer on the chuck 9, and then the movement control device drives the chuck table 4 to the light source receiving device 5, the light source emitting device 1 emits light through the wafer, and the light source receiving device 5 receives the emitted light.

[0061] The bottom of the annular structure of the chuck table 4 is provided with a circle of air holes, which can be used as air flotation holes and / or vacuum adsorption holes.

[0062] As an example, please refer to Figure 3 When the movement control device drives the chuck table 4 to move on the base plate 2, in order to prevent friction between the chuck table 4 and the base plate 2, which causes the chuck table 4 to be unstable during movement, thereby causing the wafer to shake or even fall off on the chuck 9, the circle of air holes includes a plurality of air flotation holes 403, and the air flotation holes 403 are connected to the air source. The air source blows air onto the base plate 2 through the plurality of air flotation holes 403, so that the chuck table 4 floats from the base plate 2, thereby allowing the chuck table 4 to move smoothly.

[0063] As another embodiment, when the movement control device drives the chuck table 4 to move to the desired position on the base plate 2, in order to prevent the chuck table 4 from further moving, the circle of air holes includes a plurality of vacuum adsorption holes 402. By evacuating the plurality of vacuum adsorption holes 402, the chuck table 4 is fixed on the base plate 2.

[0064] In the present invention, the chuck 9 for supporting the wafer is a translucent disk structure. Therefore, when measuring, the wafer is placed on the chuck, and due to the large contact area, the support stability can be guaranteed; and because the chuck 9 is made of a translucent material, it will not block the light emitted by the light source emitting device 1 above the wafer and pass through the wafer, and thus will not block the light source receiving device 5 from receiving the light, thereby avoiding the blind spot of the light source receiving device 5, so that the measuring device can measure all the marking points on the wafer, thereby ensuring the integrity of the measurement results and improving the yield of the wafer.

[0065] The present invention does not impose any specific restrictions on the material of the light-transmitting disk structure, as long as it can ensure that the light emitted by the light source emitting device 1 passes through the chuck 9 and is received by the light source receiving device 5. For example, the light-transmitting disk structure is made of quartz glass, which has the characteristics of high strength, high toughness, and good light transmittance (when the light source emitting device 1 is an infrared light source emitting device 1, the transmittance of quartz glass to the infrared light emitted by the light source emitting device 1 is between 90% and 92%).

[0066] In order to fix the position of the wafer and prevent the wafer from moving on the chuck 9, as an embodiment, please refer to Figure 5 and Figure 6 The translucent disk structure includes a wafer carrying area 904 and an edge limiting area 903. The edge limiting area 903 is arranged around the wafer carrying area 904 and is higher than the wafer carrying area 904. When the wafer is carried on the wafer carrying area 904, the edge limiting area 903 limits the wafer from sliding on the wafer carrying area 904.

[0067] Furthermore, the first through hole 902 is opened at the center of the wafer supporting area 904 , and the second connecting component 901 is arranged outside the edge limiting area 903 .

[0068] This embodiment provides a wafer bonding measurement device, in which the chuck 9 for supporting the wafer is a translucent disk structure with an edge limiting area 903. Therefore, during measurement, the wafer is placed on the chuck 9, which can not only ensure the support stability and limit the movement of the wafer, but also will not block the light source receiving device 5 from receiving the light, avoiding the blind spot of the light source receiving device 5, ensuring the wafer so that the measurement device can measure all the marking points on the wafer, thereby ensuring the integrity of the measurement results and improving the yield of the wafer.

[0069] Although the present invention is disclosed as above, it is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope defined by the claims.

Claims

1. A wafer bonding measurement device for measuring the offset of two wafers with marked points after bonding, characterized in that: The device includes a base plate, a movement control device, a chuck table, a chuck, a supporting ejector pin, a light source emitting device and a light source receiving device; The bottom plate and the supporting ejector are sequentially arranged from top to bottom below the light source emitting device; A circular hole is provided in the center of the bottom plate, and the light source receiving device is provided in the circular hole; the movement control device is provided on the upper surface of the bottom plate, and the movement control device is connected to the chuck stage to drive the chuck stage to move on the bottom plate; The chuck table is an annular structure with a circle of air holes at the bottom. At least three first connecting parts are provided on the outer edge of the annular structure. The chuck is a light-transmitting disk structure with the same area as the chuck table. A second connecting part corresponding to the first connecting part is provided on the outer edge of the chuck. The chuck is connected to the first connecting part and fixed to the chuck table via the second connecting part. A first through-hole corresponding to the supporting ejector pin is provided at the center of the chuck. The bottom plate is provided with a wafer loading area, and the wafer loading area is provided with a second through-hole corresponding to the supporting ejector pin. When in working state, the movement control device drives the chuck stage to move to the wafer loading area on the base plate, the first through hole is aligned with the second through hole, the support pin rises and passes through the second through hole and the first through hole to receive the wafer and place it on the chuck, and the movement control device drives the chuck stage to the light source receiving device, the light source emitting device emits light through the wafer, and the light source receiving device receives the emitted light.

2. The wafer bonding measurement device according to claim 1, wherein: The movement control device includes an X-axis driving device, an X-axis movable guide rail, a Y-axis driving device and a Y-axis movable guide rail. The X-axis movable guide rail is arranged on the base plate along the X-axis and is driven by the X-axis driving device to move the chuck table along the X-axis movable guide rail; the Y-axis movable guide rail is arranged on the base plate along the Y-axis and is driven by the Y-axis driving device to move the chuck table along the Y-axis movable guide rail.

3. The wafer bonding measurement device according to claim 1, wherein: The circle of air holes includes a plurality of air flotation holes, and air is blown onto the bottom plate through the plurality of air flotation holes, so that the chuck table floats from the bottom plate.

4. The wafer bonding measurement device according to claim 1 or 3, characterized in that: The circle of air holes includes a plurality of vacuum adsorption holes, and the chuck table is fixed on the base plate by evacuating a plurality of the vacuum adsorption holes.

5. The wafer bonding measurement device according to claim 1, wherein: The first connecting component and the second connecting portion are connected and fixed by a threaded fastener.

6. The wafer bonding measurement device according to claim 1, wherein: The translucent disk structure includes a wafer carrying area and an edge limiting area. The edge limiting area is arranged around the wafer carrying area and is higher than the wafer carrying area. When the wafer is carried on the wafer carrying area, the edge limiting area limits the wafer from sliding on the wafer carrying area.

7. The wafer bonding measurement device according to claim 6, wherein: The first through hole is opened at the center of the wafer supporting area, and the second connecting component is arranged outside the edge limiting area.

8. The wafer bonding measurement device according to claim 1, wherein: The light-transmitting disk structure is made of quartz glass.

9. The wafer bonding measurement device according to claim 1, wherein: The light source emitting device is an infrared light source emitting device.

10. The wafer bonding measurement device according to claim 1, wherein: The light source receiving device is a transmission type infrared lens.

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