TWI816180B - Multi station clamping device - Google Patents

Abstract

A multi-station clamping device includes at least two claw units. The claw unit includes at least two bases for supporting wafers, and a rotating shaft that can drive all the bases to rotate. When the rotating shaft rotates circumferentially When working, the base can be alternately in the working position; each base is provided with a guide surface and a slot. The rotating shaft rotates circumferentially, and the wafer can slide along the guide surface of the base in the working position until it falls into the slot. The slots of at least two claw units cooperate to clamp the wafer.

Description

Multi-station clamping device

The invention belongs to the technical field of semiconductor integrated circuit chip manufacturing, and is particularly directed to a wafer fixing method, and particularly relates to a multi-station clamping device.

In the existing semiconductor processing process, the wafer needs to be grabbed and transported multiple times, and two polishing fluids are used in some special processes. In order to avoid direct interaction between the polishing fluids and contamination of the wafer, The two polishing fluids cannot come into contact with each other, but the wafer grabbing mechanism will inevitably come into contact with the polishing fluid on the wafer during the transfer of the wafer. It is easy to have the problem of residues of more than two polishing fluids. In order to solve the above problem, Currently, two sets of clamping mechanisms are generally used to grab wafers. However, using two sets of clamping mechanisms has the disadvantages of high cost and large space occupation.

Moreover, currently, different clamping mechanisms need to be used for wafers of different sizes, and specific clamping mechanisms need to be set according to the size of the wafer. It is not possible to use one clamping mechanism for multiple purposes, and the cost is high.

In order to overcome the shortcomings of the prior art, the present invention provides a multi-station clamping device that can meet the needs of multiple polishing liquid processes, has reduced operating costs, has high adaptability and occupies a small space.

The technical solution adopted by the present invention to solve the technical problem is: a multi-station clamping device including at least two claw units. The claw unit includes at least two bases for supporting the wafer, and can A rotating shaft that drives all bases to rotate. When the rotating shaft rotates circumferentially, the bases can be in working positions alternately. Each base is provided with a guide surface and a slot respectively. The rotating shaft rotates circumferentially. , the wafer can slide along the guide surface of the base in the working position until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer.

The present invention is provided with at least two bases on a single claw unit. The bases can rotate and alternately be in the working position of clamping the wafer driven by the rotating shaft, so that when the process requirements of different polishing fluids need to be met, the clamping jaws can be The claw unit rotates at a certain angle to replace the base, so that there will be no mutual influence between processes, making it flexible and convenient to use; the setting of the guide surface makes it more adaptable to different wafers and has better flexibility of use.

Further, the guide surface is an inclined surface, and the inclined surface cooperates with the second inclined surface to form two opposite side walls of the slot. When the rotating shaft drives the base to rotate close to the wafer, the wafer is tilted against the inclined surface. Slide it into the card slot. The inclined surface can play a guiding role, allowing the wafer to slide into the slot in a direction that is as horizontal as possible. The slot holds the wafer more firmly and can adapt to wafers of different thicknesses.

Further, the wafer moves axially against the inclined surface until it slides into the slot, the upper edge of the wafer contacts the second inclined surface in a point contact or line contact, and the lower edge of the wafer contacts the inclined surface. The surfaces touch each other in point or line contact. The wafer is in point contact or line contact with the inclined surface and the second inclined surface. The contact area is small and will not adversely affect the performance of the wafer.

Furthermore, a third inclined surface is provided on the base and located axially above the slot, and the wafer can slide onto the inclined surface along the third inclined surface. It is convenient for placing the wafer on the inclined surface and also plays a certain guiding role.

Further, a bracket is provided on the rotating shaft, and the bracket extends outward with the axis of the rotating shaft as the center to form one or two or more extension arms, and a base is provided on each extension arm. The number of bases can be set arbitrarily to meet the needs of multiple polishing fluid processes. The length of the extension arm can also be selected according to needs, providing high flexibility in use.

Furthermore, the base is also provided with a convex portion, and the guide surface includes a supporting plane and an inclined surface. The slot is formed between the lower surface of the convex portion and the supporting plane. When the rotating shaft drives the base, When the holder rotates, the wafer slides into the slot on the supporting plane and against the inclined surface. The supporting plane supports the wafer more stably, and the inclined plane guides the placement of the wafer. The wafer can slide into the wafer receiving plane along the inclined plane, and the slot limits the wafer, even if the wafer is placed. The circle will not fall off even if it is rotated, tilted or moved.

Furthermore, the guide surface further includes a bevel two provided on the convex portion, and the wafer can enter the slot against the bevel one and the bevel two. The second inclined surface has a guiding role when the base rotates, and the wafer can slide into the slot along the second inclined surface.

Further, the number of the bases is two, which are coaxially arranged, and a notch is formed between adjacent bases, and the notch is used to prevent liquid contact on the two bases. The setting of the notch prevents the polishing fluids of the two processes from contacting each other and causing adverse effects, and ensures the independence between the processes of different processes.

Further, the axial height of the slot is greater than the axial thickness of the wafer; the bottom wall and the side wall of the slot are perpendicular to each other. The card slot not only plays a limiting role, but also avoids squeezing the surface of the wafer to ensure the performance of the wafer.

Further, the number of the bases is three, and they are arranged at intervals along the circumferential direction of the wafer. The three bases support and clamp the wafer more firmly; and the three bases can only limit the movement of the wafer without exerting force on the wafer, ensuring that the wafer will not be pinched.

The invention adopts a multi-station clamping device composed of a rotatable claw unit. When the clamping device is carrying the wafer station, the wafer can be placed vertically on the clamping device. After the claw unit of the clamping device rotates at a certain angle, the clamping device enters the fixed wafer station and the wafer cannot be removed. out, it is firmly fixed on the clamping device, and then the clamping device can make any movements without worrying about the wafer falling or being damaged. After the claw unit of the clamping device is rotated to a certain angle, it can enter the wafer ejection station, and the wafer can be ejected from the clamping device horizontally or vertically. There are at least two claw units on the clamping device, and different claw units can be selected according to different process requirements to transfer different wafers.

The claw unit of this multi-station clamping device can be composed of a single or multiple bases. When using a claw unit composed of two or more bases, it can meet the needs of multiple polishing fluids or multi-size wafers. need.

The beneficial effects of the present invention are: 1) The multi-station clamping device of the present invention can rotate, can carry wafers, and can also fix the wafers so that they will not fall when flipped or moved, and the use method is more flexible; 2 ) The multi-station clamping device of the present invention has at least two claw units on a single clamping device. Each claw unit is the same size, which can meet the process requirements of multiple polishing fluids and save time, space and cost. , the scope of use is wider; 3) The multi-station clamping device of the present invention has multiple claw units on a single clamping device, and the size of each claw unit can be different, which can meet the needs of transporting wafers of different sizes. process requirements, saving costs and having a wider range of use; 4) In the multi-station clamping device of the present invention, the bases of the claw units on a single clamping device can be 2 or more, which are replaceable and not fixed. , flexible transformation, the angular spacing between the bases can be set according to needs, allowing one machine to be used for multiple purposes.

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only These are some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of protection of the present invention.

Embodiment 1

A multi-station clamping device includes at least two claw units 1. The claw unit 1 includes at least two bases 3 for supporting wafers 2, and a rotation shaft 4 that can drive all the bases 3 to rotate. . When the rotating shaft 4 rotates circumferentially, two or more bases 3 can be in working positions alternately. The working position here refers to the working state in which the wafer 2 is placed.

Each base 3 is provided with a guide surface 31 and a slot 32 respectively. When the rotation axis 4 rotates circumferentially, the wafer 2 can move along the base 3. This refers to the guidance of the base 3 in the working position. The surface 31 slides until the wafer 2 falls into the slot 32 , and the slots 32 of the two pairs of claw units 1 cooperate to firmly clamp the wafer 2 .

As shown in Figures 1-9, in this embodiment, the guide surface 31 is an inclined surface 311. Taking the direction shown in Figure 2 as an example, the inclined surface 311 extends obliquely from top to bottom and from inside to outside. A second inclined surface 33 is also formed. The second inclined surface 33 extends obliquely from bottom to top and from inside to outside. The above-mentioned inclined surface 311 and the second inclined surface 33 face each other up and down, and cooperate to form two opposite side walls of the slot 32 . , in other words, the width of the card slot 32 varies from place to place.

When working, first place the wafer 2 on the inclined surface 311, as shown in Figure 2. At this time, the outer edge of the lower surface of the wafer 2 is set up on the inclined surface 311, and two claw units 1 appear in pairs to hold the wafer 2 To support, of course, in this embodiment, the number of claw units 1 is three, which are arranged at intervals along the circumferential direction of the wafer 2 to support the wafer 2 more stably. Then, when the rotating shaft 4 rotates and drives the base 3 to rotate close to the wafer 2 , that is, the distance between the center of the wafer 2 and the axis of the base 3 changes, the wafer 2 slides into the slot 32 against the inclined surface 311 , that is, the wafer 2 is displaced axially upward until it slides into the slot 32 , the upper edge of the wafer 2 abuts the second inclined surface 33 in a point contact manner, and the lower edge of the wafer 2 It is in point contact with the inclined surface 311 . Of course, in other embodiments, the upper edge of the wafer 2 and the second inclined surface 33 may also be in line contact, and the lower edge of the wafer 2 and the inclined surface 311 may also be in line contact.

When receiving the working position of wafer 2, the base 3 is not on the line connecting the rotation axis 4 and the center of the wafer 2. When rotating, the base 3 moves in the direction of the line connecting the rotation axis 4 and the center of the wafer 2, thereby moving the base 3 Wafer 2 is inserted into the card slot 32 . The wafer 2 is firmly clamped by the inclined surface 311 and the second inclined surface 33 , so that even if the wafer 2 is not in a horizontal position but rotates or moves, it is firmly clamped and will not fall off from the slot 32 . Moreover, the upper edge and the lower edge of the wafer 2 offset the second inclined surface 33 and the inclined surface 311 respectively. The contact area is small and has no contact with the surface of the wafer 2 at all, which plays a good protective role for the wafer 2 and maximizes the protection effect of the wafer 2. The performance of the wafer 2 itself is guaranteed, and it can be adapted to wafers 2 of different thicknesses.

In order to facilitate placing the wafer 2 on the inclined surface 311, a third inclined surface 34 is provided on the base 3 and located axially above the slot 32, which extends obliquely from top to bottom and from the inside to the outside, and the slope is greater than the slope. The wafer 2 can slide on the inclined surface 311 along the third inclined surface 34, and the third inclined surface 34 plays a good guiding role.

Each claw unit 1 is provided with at least two bases 3, and a bracket 41 is provided on the rotating shaft 4. The bracket 41 extends outward with the axis center of the rotating shaft 4 as the center to form an extension arm 411. Each extension arm 411 is equipped with a base 3.

As shown in Figure 5, the number of the extension arm 411 is one, and the two bases 3 are located at the outer ends of the extension arm 411, and the two bases 3 are coaxially arranged, and a notch 36 is formed between adjacent bases 3. The notch 36 is used to prevent polishing liquid from flowing between the two bases 3 .

Under the above structure, when the two bases 3 need to be switched, the rotation of the rotating shaft 4 drives the two bases 3 away from the wafer 2. After the wafer 2 is removed, the two bases 3 themselves first rotate circumferentially. The base 3 that was previously in the working position and holds the wafer 2 is rotated toward the outside, and the other base 3 is rotated toward the inside. Therefore, when the wafer 2 is processed using different polishing liquids, it can be clamped by two bases 3 respectively, and the residual polishing liquid will not affect another process.

Of course, as shown in FIG. 6 , the number of extension arms 411 may also be two. The two bases 3 are independent of each other and are symmetrically distributed at the outer ends of the extension arms 411 .

Under the above structure, when it is necessary to switch between the two bases 3, the rotating shaft 4 can be rotated. Taking the example shown in Figure 4 as an example, when it is necessary to replace another base 3 in the working position, the rotating shaft 4 can be rotated counterclockwise in the direction of the arrow.

Of course, as shown in FIGS. 7 and 8 , the number of extension arms 411 can also be three, four, or any other number. The outer end of each extension arm 411 is provided with a base 3 .

In order to adapt to different wafers 2 and different polishing fluids, the base 3 and the extension arm 411 are detachably connected to facilitate flexible change. The length of the extension arm 411 can also be set according to different size requirements of the wafer 2 .

Embodiment 2

As shown in Figures 10-18, in this embodiment, the base 3 is also provided with a convex portion 35. The guide surface 31 includes a supporting plane 312 and an inclined plane 313. The supporting plane 312 is a horizontal plane, and the inclined plane 313 extends from the bottom to the bottom. The wafer 2 is tilted upward and from the outside inward, and is placed on the supporting plane 312 . A slot 32 is formed between the lower surface of the convex portion 35 and the supporting plane 312 .

When the rotating shaft 4 drives the base 3 to rotate, the wafer 2 slides into the slot 32 on the supporting plane 312 and against the inclined plane 313 . As shown in Figure 18, the axial height of the slot 32 is greater than the axial thickness of the wafer 2, that is, S1>S2, and the bottom wall and the side wall of the slot 32 are perpendicular, so the side wall of the wafer 2 can be aligned with the slot. The bottom walls of 32 are in contact with each other to ensure that the wafer 2 is firmly clamped without damaging the upper surface of the wafer 2, ensuring the stability of its performance.

Of course, in other embodiments, as shown in FIG. 19 , the bottom wall 321 of the slot 32 may also be a slope, which is inclined from top to bottom and from the inside to the outside, so that the upper edge of the wafer 2 is in contact with the bottom of the slot 32 . The walls 321 are in contact to ensure that the wafer 2 is firmly clamped without damaging the upper surface of the wafer 2, ensuring the stability of its performance. Even if the wafer 2 is not in a horizontal position but rotates or moves, it can be firmly clamped and will not fall off from the card slot 32 .

In order to facilitate the smooth sliding of the wafer 2 into the card slot 32, the guide surface 31 also includes a second inclined surface 351 provided on the side of the convex portion 35. As shown in FIG. 14, the second inclined surface 351 moves from top to bottom toward the wafer 2. direction is tilted. Therefore, when the wafer 2 is placed on the base 3, it can enter the slot 32 against the first bevel 313 and the second bevel 351. Even if the wafer 2 is tilted to a certain extent, the second bevel 351 can press it down into the slot 32. within.

As shown in FIG. 14 , the number of bases 3 on one claw unit 1 is two, and they are coaxially arranged on the top surface of the rotating shaft 4 . Notches 36 are also formed between adjacent bases 3 . When one of the bases 3 is in the working position and has completed its work, the other base 3 can be rotated 180 degrees to the working position to continue working.

The multi-station clamping device structured in the first and second embodiments above can be used in large-scale chemical mechanical planarization equipment. The wafer transfer table is connected to the polishing unit and the cleaning unit, and the wafer to be polished enters the polishing unit and the polishing unit. The completed wafers must pass through the transfer stage before entering the cleaning unit. The multi-station clamping device can be used on the transfer stage to fix the wafers and facilitate the transfer of the wafers into the cleaning unit.

The above-mentioned specific embodiments are used to explain the present invention, rather than to limit the present invention. Within the spirit of the present invention and the protection scope of the patent application, any modifications and changes made to the present invention fall within the protection scope of the present invention.

1: Claw unit 2:wafer 3: base 31:Guide surface 311: Inclined surface 312:Supporting plane 313: Incline 1 32:Card slot 321: Bottom wall 33: Second inclined surface 34:Third inclined plane 35:convex part 351: Incline 2 36: Notch part 4:Rotation axis 41: Bracket 411:Extended arm

Figure 1 is a perspective view of the use state of Embodiment 1 of the present invention. FIG. 2 is a partial front view of Embodiment 1 of the present invention (the wafer is set on the guide surface and does not completely fall into the slot). FIG. 3 is a partial front view of Embodiment 1 of the present invention (the wafer is completely dropped into the slot). Figure 4 is a top view of the use state of Embodiment 1 of the present invention. Figure 5 is a schematic structural diagram of the claw unit in Embodiment 1 of the present invention. Figure 6 is a structural front view of the claw unit in Embodiment 1 of the present invention. Figure 7 is a second structural schematic diagram of the claw unit in Embodiment 1 of the present invention. Figure 8 is a schematic third structural diagram of the claw unit in Embodiment 1 of the present invention. Figure 9 is a schematic diagram 4 of the structure of the claw unit in Embodiment 1 of the present invention. Figure 10 is a perspective view of the use state of the second embodiment of the present invention. Figure 11 is a perspective view of the claw unit in Embodiment 2 of the present invention. Figure 12 is a front view of the claw unit in Embodiment 2 of the present invention. Figure 13 is a perspective view of another structure in use according to Embodiment 2 of the present invention. Figure 14 is a perspective view of a claw unit with another structure in Embodiment 2 of the present invention. Figure 15 is a schematic diagram 1 of the working process of the claw unit in Embodiment 2 of the present invention. FIG. 16 is a second schematic diagram of the working process of the claw unit in Embodiment 2 of the present invention. At this time, the claw unit clamps the wafer. FIG. 17 is a front view of the jaw unit clamping the wafer in Embodiment 2 of the present invention. Figure 18 is an enlarged view of the structure at point A in Figure 17. Figure 19 is an enlarged view of another structure at position A in Figure 17.

1: Claw unit

2:wafer

Claims (8)

A multi-station clamping device includes at least two claw units, wherein the claw unit includes at least two bases for supporting wafers, and a rotation shaft that can drive all bases to rotate, and the rotation The shaft rotates circumferentially, and the bases can alternately be in the working position; each base is provided with a guide surface and a slot. When the rotating shaft rotates circumferentially, the wafer can move along the base in the working position. The guide surface slides until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer. The guide surface is an inclined surface, and the inclined surface cooperates with the second inclined surface to form the clamping surface. On the two opposite side walls of the slot, when the rotating shaft drives the base to rotate close to the wafer, the wafer slides into the slot against the inclined surface, and there is also a wafer on the base located axially above the slot. The third inclined surface, the wafer can slide onto the inclined surface along the third inclined surface. A multi-station clamping device includes at least two claw units, wherein the claw unit includes at least two bases for supporting wafers, and a rotation shaft that can drive all bases to rotate, and the rotation The shaft rotates circumferentially, and the bases can alternately be in the working position; each base is provided with a guide surface and a slot. When the rotating shaft rotates circumferentially, the wafer can move along the base in the working position. The guide surface slides until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer. The guide surface is an inclined surface, and the inclined surface cooperates with the second inclined surface to form the clamping surface. On the two opposite side walls of the slot, when the rotating shaft drives the base to rotate close to the wafer, the wafer slides into the slot against the inclined surface, and a bracket is provided on the rotating shaft, and the bracket is The axis of the rotating shaft extends outward from the center to form one or two or more extension arms, and each extension arm is provided with a base. A multi-station clamping device includes at least two claw units, wherein the claw unit includes at least two bases for supporting wafers, and a rotation shaft that can drive all bases to rotate, and the rotation The shaft rotates circumferentially, and the bases can alternately be in the working position; each base is provided with a guide surface and a slot. When the rotating shaft rotates circumferentially, the wafer can move along the base in the working position. The guide surface slides until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer, wherein the base is also provided with a convex portion, the guide surface includes a supporting plane, and Incline 1, the slot is formed between the lower surface of the protrusion and the supporting plane. When the rotating shaft drives the base to rotate, the wafer slides into the slot on the supporting plane against the inclined plane. The multi-station clamping device as claimed in claim 3, wherein the guide surface further includes a bevel two provided on the convex portion, and the wafer can enter the slot against the bevel one and the bevel two. The multi-station clamping device according to claim 3, wherein the number of the bases is two, which are arranged coaxially, and a notch is formed between adjacent bases, and the notch is used to prevent the two bases from liquid contact. The multi-station clamping device according to claim 3, wherein the axial height of the slot is greater than the axial thickness of the wafer; the bottom wall and the side wall of the slot are perpendicular to each other. A multi-station clamping device includes at least two claw units, wherein the claw unit includes at least two bases for supporting wafers, and can drive all There is a rotating shaft for rotating the base. The rotating shaft rotates circumferentially, and the base can be in the working position alternately. Each base is provided with a guide surface and a slot. When the rotating shaft rotates circumferentially, The wafer can slide along the guide surface of the base in the working position until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer, wherein the number of the bases is three, They are arranged at intervals along the circumferential direction of the wafer. A multi-station clamping device includes at least two claw units, wherein the claw unit includes at least two bases for supporting wafers, and a rotation shaft that can drive all bases to rotate, and the rotation The shaft rotates circumferentially, and the bases can alternately be in the working position; each base is provided with a guide surface and a slot. When the rotating shaft rotates circumferentially, the wafer can move along the base in the working position. The guide surface slides until it falls into the slot, and the slots of at least two claw units cooperate to clamp the wafer. The guide surface is an inclined surface, and the inclined surface cooperates with the second inclined surface to form the clamping surface. On the two opposite side walls of the slot, when the rotation axis drives the base to rotate close to the wafer, the wafer slides into the slot against the inclined surface, and the number of the bases is two, which are coaxially arranged and adjacent to each other. A notch is formed between the bases, and the notch is used to prevent liquid contact on the two bases.

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