CN112103239A - Device for clamping silicon wafer in visual detection process of silicon wafer - Google Patents

Abstract

The embodiment of the invention discloses a device for clamping a silicon wafer in the visual detection process of the silicon wafer, which comprises: the silicon wafer clamping device comprises at least two clamping jaw pairs arranged in the directions of different diameters of a silicon wafer, wherein each clamping jaw pair can move between a clamping position and a loosening position; a holder for holding the jaw pair; when the claw pair is in the loosening position, the elastic resetting component generates elastic restoring force for resetting the claw pair to the clamping position; a cam having a major axis and a minor axis; a drive mechanism for producing relative rotational movement between the at least two pairs of jaws and the cam such that the pairs of jaws can assume a first relative position aligned with the long axis of the cam in which the cam holds the pairs of jaws in the release position against the elastic restoring force produced by the elastic return member, and a second relative position aligned with the short axis of the cam in which the cam does not act on the pairs of jaws.

Description

A device for holding silicon wafers during visual inspection of silicon wafers

technical field

The invention relates to the technical field of semiconductor manufacturing, in particular to a device for clamping silicon wafers during visual inspection of silicon wafers.

Background technique

With the rapid development of the information age, the society's demand for electronic chips has grown rapidly. At the same time, people have higher and higher requirements for the quality of silicon wafers, the raw material for making chips.

During the manufacturing process of silicon wafers, defects may occur on the silicon wafers, including edge chipping, scratches, cracks, etc. These defects will bring great risks to further downstream production and utilization. inspection is crucial. For 300mm silicon wafers, visual inspection is an important defect detection method. This method refers to irradiating the beam generated by a strong light to the surface of the silicon wafer, and at the same time, the surface and edge of the silicon wafer are illuminated by the beam. The area is visually inspected by human eyes to intercept defective silicon wafers.

In the process of visual inspection by human eyes, it is necessary to use a clamping device to clamp the silicon wafer. However, the existing clamping device has the following disadvantages: the clamping claw of the clamping device realizes clamping by contacting the peripheral edge of the silicon wafer, and the part of the clamping claw adjacent to the peripheral edge of the silicon wafer will block the sight of the visual inspection personnel , so there will be a detection blind area, resulting in missed detection in the clamping area; on the other hand, the light beam generated by the strong light will inevitably irradiate on the claw in contact with the silicon wafer, thus forming a strong reflection, affecting Visual inspection personnel's judgment of defects. These situations can cause defective wafers to enter downstream production processes, resulting in greater production losses.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the embodiments of the present invention are expected to provide a device for clamping silicon wafers during the visual inspection of silicon wafers, which can avoid the formation of detection blind spots and realize the detection of peripheral parts of silicon wafers without dead ends. .

The technical scheme of the present invention is realized as follows:

An embodiment of the present invention provides a device for clamping a silicon wafer during visual inspection of a silicon wafer, and the device may include:

At least two pairs of jaws arranged in different diameter directions of the silicon wafer, each pair of jaws can be in contact with the periphery of the silicon wafer to clamp the silicon wafer at a clamping position and away from the silicon wafer the periphery of the wafer to release the silicon wafer to move between the release positions;

a holder for holding the at least two pairs of jaws, the holder being provided with a movement guide for guiding the pair of jaws to move between the clamping position and the releasing position;

an elastic reset member for each pair of jaws, which generates an elastic restoring force that resets the pair of jaws to the clamping position when the pair of jaws is in the release position;

a cam arranged coaxially perpendicular to the central axis of the silicon wafer, the cam has a long axis and a short axis;

A driving mechanism, the driving mechanism is used to generate a relative rotational movement around the central axis between the at least two pairs of jaws and the cam, so that the pair of jaws can be positioned at the long axis of the cam an aligned first relative position and a second relative position aligned with the stub axis of the cam in which the cam pushes the card against an elastic return force generated by the elastic return member The pair of pawls remains in the released position, and in the second relative position, the cam does not act on the pair of pawls.

The embodiment of the present invention provides a device for clamping a silicon wafer during a visual inspection of a silicon wafer, which can realize that the at least two pairs of jaws can clamp or release the silicon wafer alternately or sequentially, Moreover, since the at least two pairs of jaws are arranged in different diameter directions of the silicon wafer, clamping can be achieved by contacting different parts of the periphery of the silicon wafer. When the first part of the silicon wafer is in contact with the detection blind area, or the light beam generated by the reflected strong light forms a strong reflection, the silicon wafer can be clamped by contacting the second part of the edge of the silicon wafer through another pair of jaws. and the one pair of jaws can be kept away from the edge of the silicon wafer, thereby eliminating the detection blind area produced by it, and making it no longer form strong reflections.

Description of drawings

FIG. 1 is a schematic top view of a device for clamping a silicon wafer during visual inspection of a silicon wafer according to an embodiment of the present invention;

FIG. 2 is a schematic front view of a device for clamping a silicon wafer during visual inspection of a silicon wafer according to an embodiment of the present invention;

3 is a schematic diagram of a working process of an apparatus for clamping a silicon wafer during a visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the cam rotates from the position shown in FIG. 1 to the position shown in the figure;

4 is a schematic diagram of a working process of a device for clamping a silicon wafer during a visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the cam rotates from the position shown in FIG. 3 to the position shown in the figure;

5 is a schematic diagram of a working process of an apparatus for clamping a silicon wafer during a visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the cam rotates from the position shown in FIG. 4 to the position shown in the figure;

6 is a schematic diagram of a working process of an apparatus for clamping a silicon wafer during a visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the cam rotates from the position shown in FIG. 5 to the position shown in the illustration;

7 is a schematic diagram of a working process of an apparatus for clamping a silicon wafer during a visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the cam rotates from the position shown in FIG. 6 to the position shown in the figure;

8 is a schematic diagram of the positional relationship between the long axis of a cam of a device for holding a silicon wafer during visual inspection of a silicon wafer and an illuminated area of a light beam according to an embodiment of the present invention;

FIG. 9 is a schematic top view of another device for clamping silicon wafers during visual inspection of silicon wafers according to an embodiment of the present invention;

FIG. 10 is a schematic front view of an apparatus for clamping a silicon wafer during visual inspection of a silicon wafer according to an embodiment of the present invention, wherein the rod part and the abutting part of the jaw half are shown in detail.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to FIG. 1 and FIG. 2 , an embodiment of the present invention provides an apparatus 100 for clamping a silicon wafer W during a visual inspection process of a silicon wafer W, wherein the silicon wafer is schematically shown by a dotted circle in FIG. 1 . W, the apparatus 100 may include:

At least two pairs of claws 110 arranged in different diameter directions of the silicon wafer W, wherein, three pairs of claws 110 are exemplarily shown in FIG. The second jaw pair 110-2 and the third jaw pair 110-3, and as shown in FIG. 1, the first jaw pair 110-1 includes two jaw halves 110-1A and 110-1B, The second pair of jaws 110-2 includes two jaw halves 110-2A and 110-2B, and the third pair of jaws 110-3 includes two jaw halves 110-3A and 110-3B, each jaw The pair 110 is movable between a clamping position in contact with the periphery of the silicon wafer W to clamp the wafer W and a release position away from the periphery of the wafer W to release the wafer W, As shown in FIG. 1 , the first pair of jaws 110-1 is in the release position, while the second pair of jaws 110-2 and the third pair of jaws 110-3 are in the clamped position;

A holder 120 for holding said at least two pairs of jaws 110, said holder 120 being provided with movement guides for guiding the movement of said pair of jaws 110 between said clamping position and said releasing position Part 121, wherein, FIG. 1 only schematically shows the movement guide part 121 for guiding the jaw half 110-1A, it can be understood that the movement guide part 121 can be formed in the holder 120, for example through holes or grooves;

A resilient return member 130 for each pair of jaws 110 that produces a return of the pair of jaws 110 to the clamped position when the pair of jaws 110 is in the released position elastic resilience;

A cam 140 arranged coaxially with the central axis X of the silicon wafer W, the cam 140 has a long axis L and a short axis S, as shown by the dotted line in FIG. 1 ;

As shown in the driving mechanism 150 in FIG. 2 , the driving mechanism 150 is used to generate a relative rotational movement around the central axis X between the at least two pairs of jaws 110 and the cam 140 , so that the The pair of jaws 110 can be in a first relative position aligned with the long axis L of the cam 140, which is shown in FIG. 1, and a second relative position aligned with the short axis S of the cam 140 In the first relative position, the cam 140 resists The elastic restoring force generated by the elastic restoring member 130 maintains the pair of pawls 110 in the release position, and in the second relative position, the cam 140 does not act on the pair of pawls 110 .

Hereinafter, the working process of the device 100 will be described in detail by taking the clockwise rotation of the cam 140 to generate the relative rotational motion between the at least two jaw pairs 110 and the cam 140 as an example.

Referring to FIG. 3 , the cam 140 is rotated from the position shown in FIG. 2 (shown by dashed lines) to the position shown in FIG. 3 (shown by solid lines). During this process, the long axis L of the cam 140 gradually deviates from the pair of pawls 110 - 1 , whereby the pair of pawls 110 - 1 moves in a radially inward direction under the action of the elastic restoring force generated by the elastic restoring member 130 Move until it abuts against the portion on the cam 140 that is aligned with the pair of jaws 110-1.

Referring to FIG. 4 , the cam 140 continues to rotate from the position shown in FIG. 3 (shown by dashed lines) to the position shown in FIG. 4 (shown by solid lines). During this process, the pair of jaws 110-1 further moves in the radially inward direction under the action of the elastic restoring force generated by the elastic restoring member 130 until it contacts the peripheral edge of the silicon wafer W and is in the clamping position. When the jaw pair 110-1 still abuts on the cam 140.

Referring to FIG. 5 , the cam 140 continues to rotate from the position shown in FIG. 4 (shown by dashed lines) to the position shown in FIG. 5 (shown by solid lines), ie, the short axis S of the cam 140 and the pair of jaws 110 -1 for alignment. During this process, the pair of claws 110-1 cannot move further radially inward due to the contact with the peripheral edge of the silicon wafer W, and the portion on the cam 140 aligned with the pair of claws 110-1 and the pair of claws 110- The distance between 1 gradually increases, or the cam 140 does not act on the pawl pair 110-1.

Referring to Figure 6, the cam 140 continues to rotate from the position shown in Figure 5 (shown by dashed lines) to the position shown in Figure 6 (shown by solid lines), ie just abutting the pair of jaws 110-1 again, During this process, the pair of jaws 110-1 has not been affected by the cam 140, so it is always in the clamping position or does not move in the radial direction.

Referring to Figure 7, the cam 140 continues to rotate from the position shown in Figure 6 (shown by dashed lines) to the position shown in Figure 7 (shown by solid lines). During this process, the long axis L of the cam 140 gradually approaches the pair of jaws 110-1, whereby the cam 140 makes the pair of jaws 110-1 along the radially outward direction against the elastic restoring force generated by the elastic restoring member 130. direction move.

Finally, the cam 140 is rotated from the position shown in FIG. 7 to the position shown in FIG. 1 , in the process, the pawl pair 110 - 1 is further moved in the radially outward direction until the length of the cam 140 is The axis L is aligned as shown in FIG. 1 .

To sum up, in the process of one rotation of the cam 140, the pair of jaws 110-1 can clamp and release the silicon wafer W. There are at least two pairs of claws 110 , so it can be understood that the at least two pairs of claws 110 can also clamp and release the silicon wafer W. In this way, the at least two jaw pairs 110 can clamp or release the silicon wafer W alternately or sequentially, and since the at least two jaw pairs 110 are arranged in different diameter directions of the silicon wafer W Therefore, the clamping can be realized by contacting different parts in the periphery of the silicon wafer W. In this way, when a pair of jaws 110 is in contact with the first part in the edge of the silicon wafer W, a detection blind area is generated, or due to strong reflection When the light beam generated by the light lamp forms strong reflection, the silicon wafer W can be clamped by another pair of jaws 110 in contact with the second part of the edge of the silicon wafer W, and the pair of jaws 110 can be kept away from The edge of the silicon wafer W, thereby eliminating the detection blind area generated by it, and making it no longer form a strong reflection.

For the shape of the cam 140 in the device 100 , referring to FIG. 1 , in a preferred embodiment of the present invention, the cross-section of the cam 140 in a plane parallel to the silicon wafer W may be an ellipse. The ellipse has a major axis and a minor axis, and the curve constituting the ellipse is smooth or smooth, so that the pair of jaws 110 can be smoothly moved in the radial direction, or the pair of jaws 110 will not be moved A sudden change in velocity occurs during movement in the radial direction.

In a preferred embodiment of the present invention, the at least two jaw pairs 110 may be uniformly distributed in the circumferential direction of the silicon wafer W. For example, in the case of three pairs of jaws 110 shown in FIG. 1 , the included angle between two adjacent pairs of jaws 110 in the circumferential direction of the silicon wafer W may be 60 degrees. For example, in the device 100 In the case of including four pairs of claws 110 (not shown in the drawings), the included angle between two adjacent pairs of claws 110 in the circumferential direction of the silicon wafer W may be 45 degrees, and so on. Compared with the non-uniformly distributed jaw pairs, the uniformly distributed jaw pairs can achieve more stable clamping of the silicon wafer W.

In a preferred embodiment of the present invention, when one jaw pair 110 of the at least two jaw pairs 110 is in the release position, the other jaw pair 110 is in the clamping position. In other words, during the relative rotational movement between the at least two pairs of jaws 110 and the cam 140, only one pair of jaws 110 is in the release position, so that as many jaw pairs as possible can pass through 110 clamps the silicon wafer, which is beneficial to the stability of the clamping. It can be understood that the above solution can be easily realized by reasonably selecting the lengths of the long axis L and the short axis S of the cam 140 and the length of the jaw pair 110 in the radial direction of the silicon wafer W according to the diameter of the silicon wafer W. . For example, it can be seen from FIG. 3 and FIG. 6 that the lengths of the long axis L and the short axis S of the cam 140 and the length of the jaw pair 110 in the radial direction of the silicon wafer W can realize the above solution. More specifically, as shown in FIGS. 3 and 6 , when the cam 140 abuts the first pair of jaws 110-1, the second pair of jaws 110-2 and the third pair of jaws 110-3 and the cam There are gaps between 140.

For the realization of the relative rotational movement between the at least two pairs of jaws 110 and the cam 140, in an example of the present invention, the at least two pairs of jaws 110 are fixed, and the drive The mechanism 150 drives the cam 140 to rotate relative to the at least two pairs of jaws 110 around the central axis X, thereby realizing the relative rotational movement between the at least two pairs of jaws 110 and the cam 140 in a simple manner .

In practice, the light beam generated by the strong light used for visual inspection of silicon wafers will only illuminate part of the wafer but not all, and usually the strong light is fixed or the light beam generated by the strong light is There is no movement, therefore, the silicon wafer needs to be rotated so that the light beam can illuminate the entire area of the silicon wafer. Therefore, in the preferred embodiment of the present invention, the cam 140 is fixed, and the driving The mechanism 150 drives the at least two jaw pairs 110 to rotate about the central axis X relative to the cam 140 . Thus, the silicon wafer W held by the pair of jaws 110 will rotate together, so that the entire area of the silicon wafer W can be illuminated by the light beam.

With the pair of jaws 110 rotating together with the wafer W, it is desirable, as shown in FIG. 8, that when the jaw half 110-1A rotates clockwise into the area illuminated by the light beam generated by the strong light (shown by hatching), the first pair of jaws 110-1 is in the release position, so as to inspect the portion corresponding to the jaw half 110-1A in the periphery of the silicon wafer W, or to make The jaw half 110-1A does not reflect light, therefore, in a preferred embodiment of the present invention, referring to FIG. .

It can be understood that, for the above-mentioned elastic reset member 130, there may be various implementations, for example, the elastic reset member 130 may be a helix arranged between the two jaw halves of the jaw pair 110, such as in a stretched state. Springs, however, in a preferred embodiment of the present invention, referring to FIG. 1, the resilient return member 130 comprises a coil spring for each jaw half of each jaw pair 110, the first The ends are fixedly connected to the retainer 120 and the second end of the coil spring is fixedly connected to the jaw halves. With this arrangement, not only the jaw pair 110 as a whole can be in the clamping position and the release position, but also each jaw half can be in the clamping position and the release position.

When the jaw pair 110 moves between the release position and the clamping position, the jaw pair slides along the surface of the cam 140. In order to make this sliding in a more advantageous manner, in the preferred embodiment of the present invention 9, each jaw half 110-1A, 110-1B, 110-2A, 110-2B, 110-3A, 110- 3B is provided with a roller follower 111 configured to roll on the surface of the cam 140 during relative rotational movement of the at least two pairs of jaws 110 and the cam 140 .

The above-mentioned jaw halves can be implemented in various ways. In a preferred embodiment of the present invention, referring to FIG. 10 , each jaw half of each jaw pair 110 includes a rod portion 112 and an abutment portion 113 . The rod The portion 112 extends parallel to the silicon wafer W, and the abutting portion 113 is provided at the radially outward end of the rod portion 112 and extends perpendicularly to the rod portion 112 to meet the jaw pair 110 In contact with the edge of the silicon wafer W when in the clamping position.

It should be noted that the technical solutions described in the embodiments of the present invention may be combined arbitrarily unless there is a conflict.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A device for clamping a silicon wafer in a silicon wafer visual inspection process, wherein the device comprises: At least two pairs of jaws arranged in different diameter directions of the silicon wafer, each pair of jaws can be in contact with the periphery of the silicon wafer to clamp the silicon wafer at a clamping position and away from the silicon wafer the periphery of the wafer to release the silicon wafer to move between the release positions; a holder for holding the at least two pairs of jaws, the holder being provided with a movement guide for guiding the pair of jaws to move between the clamping position and the releasing position; an elastic reset member for each pair of jaws, which generates an elastic restoring force that resets the pair of jaws to the clamping position when the pair of jaws is in the release position; a cam arranged coaxially perpendicular to the central axis of the silicon wafer, the cam has a long axis and a short axis; A driving mechanism, the driving mechanism is used to generate a relative rotational movement around the central axis between the at least two pairs of jaws and the cam, so that the pair of jaws can be positioned at the long axis of the cam an aligned first relative position and a second relative position aligned with the stub axis of the cam in which the cam pushes the card against an elastic return force generated by the elastic return member The pair of pawls remains in the released position, and in the second relative position, the cam does not act on the pair of pawls. 2 . The device of claim 1 , wherein a cross-section of the cam in a plane parallel to the silicon wafer is elliptical. 3 . 3. The device according to claim 1 or 2, wherein the at least two pairs of jaws are evenly distributed in the circumferential direction of the silicon wafer. 4 . The device according to claim 1 or 2 , wherein when one of the at least two pairs of jaws is in the release position, the other pair of jaws is in the clamping position. 5 . 5 . The device according to claim 1 or 2 , wherein the at least two pairs of jaws are fixed, and the driving mechanism drives the cam to be relative to the at least two jaws around the central axis. 6 . Claw pair rotates. 6 . The device according to claim 1 or 2 , wherein the cam is fixed, and the driving mechanism drives the at least two pairs of jaws to rotate relative to the cam around the central axis. 7 . 7. The apparatus of claim 6, wherein the extended line of the long axis of the cam intersects the light beam illuminating the periphery of the silicon wafer. 8. The device of claim 1 or 2, wherein the resilient return member comprises a helical spring for each jaw half of each jaw pair, the first end of the helical spring Fixedly connected to the retainer, the second end of the coil spring is fixedly connected to the jaw half. 9. The device of claim 1 or 2, wherein each jaw half of each jaw pair is provided with a roller follower configured to The pair of jaws rolls on the surface of the cam during the relative rotational movement of the cam. 10. The device of claim 1 or 2, wherein each pawl half of each pawl pair includes a rod portion and an abutment portion, the rod portion extending parallel to the silicon wafer, so that The abutment is provided at a radially outward end of the stem and extends perpendicular to the stem to contact the edge of the silicon wafer when the pair of jaws is in the clamping position .

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