Non-contact wafer flipping device and flipping method

Abstract

The present invention provides a non-contact wafer flipping device and flipping method, which belongs to the field of semiconductor manufacturing technology, and includes a rotating finger cylinder, two groups of wafer clamping supports, and a wafer clamping robot. The rotating finger cylinder has at least 180 degrees of freedom of rotation and the freedom of relative movement of the fingers; the two groups of wafer clamping supports are symmetrically fixed on the two fingers of the rotating finger cylinder; the wafer clamping robot is symmetrically connected to the wafer clamping supports to clamp the wafer to be flipped; the inner sides of the two wafer clamping robots are respectively provided with arc grooves for clamping the edges of the wafer. The wafer clamping robot of the present invention does not contact the surface of the wafer, but only rests on the outer side of the wafer, and will not cause contamination, scratches, and other unclean problems on the front and back of the wafer; the wafer slides along the inclined surface and falls into the clamping part of the wafer clamping robot, which can avoid the uncertainty caused by problems such as wafer tilting and shaking.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a non-contact wafer flipping device and a wafer flipping method based on the flipping device. Background Art

[0002] The semiconductor wafer manufacturing process involves numerous steps, some of which involve double-sided fabrication, such as double-sided cleaning, double-sided etching, and double-sided marking. This double-sided fabrication requires wafer flipping. Currently, the most common wafer flipping method uses a rotatable robotic finger to flip the wafer, typically using a vacuum chuck to hold the wafer to the finger. However, due to the contact between the robotic finger and the wafer surface, this method inevitably stains or even scratches the wafer surface, failing to meet wafer surface cleanliness requirements. Summary of the Invention

[0003] An embodiment of the present invention provides a non-contact wafer flipping device that flips the wafer in a contactless manner, thereby avoiding the problem of contact-type wafer flipping causing stains or even scratches on the wafer surface and failing to meet the wafer surface cleanliness requirements.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a non-contact wafer flipping device, including: a rotating finger cylinder, two groups of wafer clamping supports and a wafer clamping robot, which has at least 180° rotation freedom and freedom of relative movement of fingers; the two groups of wafer clamping supports are symmetrically fixed on the two fingers of the rotating finger cylinder; the wafer clamping robot is symmetrically connected to the wafer clamping support to clamp the wafer to be flipped; the opposite inner sides of the two wafer clamping robots respectively have arc grooves for clamping the edge of the wafer.

[0005] In combination with the first aspect, in a possible implementation, the inner wall of the arc-shaped groove has a first supporting bevel, a vertical clamping surface, a second guiding bevel and a third supporting bevel connected in sequence along the width direction of the groove; wherein the inclination direction of the first supporting bevel is opposite to the inclination direction of the second guiding bevel and the third supporting bevel; the inclination angle of the second guiding bevel is greater than the inclination angle of the third supporting bevel; the width of the vertical clamping surface is greater than or equal to the thickness of the wafer.

[0006] In combination with the first aspect, in a possible implementation, a radial length of the second guide slope along the arcuate groove is greater than a radial length of the third support slope along the arcuate groove.

[0007] In combination with the first aspect, in a possible implementation, the inclination angle of the first supporting inclined surface is: 0°<α<10°, and the inclination angle of the third supporting inclined surface is: 0°<β<10°.

[0008] In combination with the first aspect, in a possible implementation, the wafer clamping robot has an arc-shaped structure.

[0009] In combination with the first aspect, in a possible implementation, a buffer is further included, and the buffer is arranged between the wafer clamping robot and the wafer clamping support.

[0010] In combination with the first aspect, in a possible implementation, the buffer is an elastic rubber block connected between the wafer clamping robot and the wafer clamping support.

[0011] In combination with the first aspect, in a possible implementation, the wafer clamping support member has a finger connecting section, an arc-shaped support section and a robot connecting section connected in sequence, wherein the finger connecting section is connected in parallel to the outer side of the finger, and the robot connecting section is connected to the outer side of the wafer clamping robot along the radial direction of the arc-shaped groove.

[0012] In a second aspect, an embodiment of the present invention further provides a non-contact wafer flipping method, based on the non-contact wafer flipping device, the method includes:

[0013] The rotating finger cylinder drives the wafer clamping robot to move in the opposite direction and open until the distance between the vertical clamping surfaces on both sides is greater than the diameter of the wafer;

[0014] The wafer removal robot carries the wafer horizontally and extends between the two vertical clamping surfaces;

[0015] The wafer-taking robot moves downward until the wafer is supported on the first supporting inclined surface;

[0016] The rotating finger cylinder drives the wafer clamping manipulators on both sides to move toward each other, and the wafer moves along the first support slope toward the vertical clamping surface until the wafer is clamped between the two vertical clamping surfaces;

[0017] The rotating finger cylinder drives the wafer clamping robot to flip 180 degrees until the back of the wafer is horizontally facing upwards;

[0018] The rotating finger cylinder drives the wafer clamping manipulator to move in the opposite direction again, and the wafer slides downward along the second guide slope until it reaches the third support slope;

[0019] The wafer removal robot extends horizontally to move the wafer upward until the wafer reaches between the two vertical clamping surfaces and then removes the wafer;

[0020] The rotating finger cylinder drives the wafer clamping robot to rotate in the opposite direction to the initial position to flip the next wafer.

[0021] The non-contact wafer flipping device and flipping method provided by the present invention have the following advantages compared with the prior art: a rotating finger cylinder is used to drive a wafer clamping robot to flip and clamp the wafer; the wafer clamping support is installed on the two fingers of the rotating finger cylinder, which can drive the wafer clamping robot to move toward each other to clamp the wafer or move backward to release the wafer; the wafer clamping robot has an arc-shaped groove, and the wafer is fixed in the groove when clamped. After flipping 180°, the wafer is released and slides onto the inclined surface so that it can be taken away by the wafer-taking robot.

[0022] The wafer clamping robot of the present invention does not contact the surface of the wafer, but only rests against the outer side of the wafer, and will not cause pollution, scratches and other unclean problems on the front and back of the wafer; the wafer slides along the inclined surface and falls into the clamping part of the wafer clamping robot, which can avoid the uncertainty caused by problems such as wafer tilting and shaking.

[0023] The present invention has a simple structure, fewer parts, is driven only by gas, and has high reliability. It does not contact the wafer surface during the wafer flipping process, avoiding contamination or damage to the wafer, and can ensure the cleanliness requirements of the wafer. At the same time, it has a simple structure and good reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the three-dimensional structure of a non-contact wafer flipping device provided in an embodiment of the present invention;

[0025] Figure 2 A schematic structural diagram of a wafer clamping robot provided in an embodiment of the present invention;

[0026] Figure 3 A schematic structural diagram of a wafer movement process provided by an embodiment of the present invention;

[0027] Figure 4 A flowchart of the non-contact wafer flipping method provided by an embodiment of the invention;

[0028] Description of reference numerals:

[0029] 1. Rotating finger cylinder; 2. Rotating assembly; 3. Finger; 4. Wafer clamping support; 5. Buffer; 6. Wafer clamping robot; 601. First supporting slope; 602. Vertical clamping surface; 603. Second guide slope; 604. Third supporting slope. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0031] Please also refer to Figure 1 and Figure 2 The non-contact wafer flipping device provided by the present invention is now described. The non-contact wafer flipping device comprises a rotating finger cylinder 1, two sets of wafer clamping supports 4, and a wafer clamping manipulator 6. The rotating finger cylinder 1 has at least 180° of rotational freedom and the freedom of relative movement of the fingers 3. The two sets of wafer clamping supports 4 are symmetrically fixed to the two fingers 3 of the rotating finger cylinder 1. The wafer clamping manipulator 6 is symmetrically connected to the wafer clamping supports 4 to clamp the wafer to be flipped. The two wafer clamping manipulators 6 have arcuate grooves on their opposing inner sides for clamping the wafer edge.

[0032] The non-contact wafer flipping device provided by the present invention has the following beneficial effects compared with the prior art: the wafer is flipped and clamped by driving the wafer clamping robot 6 using the rotating finger cylinder 1; the wafer clamping support 4 is installed on the two fingers 3 of the rotating finger cylinder 1, which can drive the wafer clamping robot 6 to move toward each other to clamp the wafer or move backward to release the wafer; the wafer clamping robot 6 has an arc-shaped groove, and the wafer is fixed in the groove when clamped. After flipping 180°, the wafer is released and slides onto the inclined surface so that it can be taken away by the wafer-taking robot.

[0033] The wafer clamping robot 6 of the present invention does not contact the surface of the wafer, but only rests against the outer side of the wafer, and will not cause pollution, scratches and other unclean problems on the front and back of the wafer; the wafer slides along the inclined surface and falls into the clamping part of the wafer clamping robot 6, which can avoid the uncertainty caused by problems such as wafer tilting and shaking.

[0034] The present invention has a simple structure, fewer parts, is driven only by gas, and has high reliability. It does not contact the wafer surface during the wafer flipping process, avoiding contamination or damage to the wafer, can ensure the cleanliness requirements of the wafer, and reduce the production cost of semiconductor devices. At the same time, it has a simple structure and good reliability.

[0035] In some embodiments, as Figure 2 As shown, the inner wall of the arc-shaped groove has a first supporting slope 601, a vertical clamping surface 602, a second guiding slope 603 and a third supporting slope 604 connected in sequence along the width direction of the groove; wherein, the inclination direction of the first supporting slope 601 is opposite to the inclination directions of the second guiding slope 603 and the third supporting slope 604; the inclination angle of the second guiding slope 603 is greater than the inclination angle of the third supporting slope 604; the width of the vertical clamping surface 602 is greater than or equal to the thickness of the wafer.

[0036] After the wafer is placed in the wafer clamping robot 6, it slides along the first supporting slope 601 to between the vertical clamping surfaces 602. Since both sides of the vertical clamping surface 602 are connected to the guiding slopes, the vertical clamping surfaces 602 only contact the side of the wafer and do not contact the front and back of the wafer. This prevents the wafer clamping robot 6 from causing stains or scratches on the wafer surface. When flipping, the wafer moves along the second guiding slope 603 to the third supporting slope 604. Due to the setting of the guiding slopes, the wafer only contacts the side of the wafer clamping robot 6 from beginning to end. In particular, when on each slope, only the upper and lower outer diameter lines of the wafer contact the slopes, achieving non-contact wafer flipping, greatly improving the cleanliness of the wafer flipping process, and providing a reliable foundation for the subsequent production of semiconductor devices. The guiding slopes provide a large space and also make it easier for the wafer removal robot to remove the wafer.

[0037] In some embodiments, as Figure 2 As shown, the radial length of the second guide slope 603 along the arcuate groove is greater than the radial length of the third support slope 604. The longer radial length of the second guide slope 603 reduces the inclination of the second guide slope 603, allowing the wafer to slide smoothly from the second guide slope 603 to the third support slope 604, and also providing more space for the wafer to be removed.

[0038] In some embodiments, as Figure 2 As shown, the inclination angle of the first supporting slope 601 is: 0° < α < 10°, and the inclination angle of the third supporting slope 604 is: 0° < β < 10°. The inclination angles of the first supporting slope 601 and the third supporting slope 604 are non-zero, and the inclination angles are relatively small, substantially close to horizontal, to ensure that the wafer does not slide when supported on these two slopes. For example, the supporting slopes can be 1°, 4°, 5°, 7°, 8°, etc.

[0039] In some embodiments, as Figure 1 and Figure 2 As shown, the wafer clamping robot 6 has an arc-shaped structure, which can reduce the size and occupied space of the wafer clamping robot 6.

[0040] The non-contact wafer flipping device provided by the present invention is as follows: Figure 1 As shown, a buffer 5 is also included, which is arranged between the wafer clamping robot 6 and the wafer clamping support 4. The buffer 5 between the wafer clamping support 4 and the wafer clamping robot 6 adjusts the clamping force, has a buffering effect on the clamping of the wafer, and avoids the problem of wafer breakage caused by hard clamping force.

[0041] In some embodiments, as Figure 1As shown, the buffer 5 is an elastic rubber block connected between the wafer clamping robot 6 and the wafer clamping support 4. The buffer 5 provides sufficient clamping force to prevent the wafer from sliding during the flipping process. The buffer 5 can also be a spring. When connected with a spring, a connecting rod slidably connected to the wafer clamping support 4 can be provided on the outside of the wafer clamping robot 6. The spring is mounted on the connecting rod, and the two ends of the spring connect the wafer clamping robot 6 and the wafer clamping support 4.

[0042] In some embodiments, as Figure 1 As shown, the wafer clamping support 4 has a finger 3 connecting section, an arc-shaped support section and a robot connecting section connected in sequence, wherein the finger 3 connecting section is connected in parallel to the outer side of the finger 3, and the robot connecting section is connected to the outer side of the wafer clamping robot 6 along the radial direction of the arc-shaped groove.

[0043] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0044] like Figure 1 As shown, the rotating finger cylinder 1 provided by the present invention consists of three parts: a main body, a rotating assembly 2 and fingers 3. The appropriate model can be purchased according to the design requirements. The rotating finger cylinder 1 is controlled by two gasses with a certain pressure. The first gas controls the rotation of the rotating assembly 2. It rotates 180° when the gas is supplied in the forward direction, and rotates 180° in the reverse direction and returns to its original position when the gas is supplied in the reverse direction. The second gas controls the movement of the fingers 3. The fingers 3 move toward each other when the gas is supplied in the forward direction, and move in the opposite direction when the gas is supplied in the reverse direction. The two fingers 3 move at the same speed but in opposite directions. The two wafer clamping supports 4 are respectively fixed on the two fingers 3 of the rotating finger cylinder 1. The two wafer clamping robots 6 are used to clamp the wafers. The two buffers 5 are located between the wafer clamping supports 4 and the wafer clamping robots 6 to provide appropriate clamping force.

[0045] Based on the same inventive concept, the embodiment of the present invention also provides a non-contact wafer flipping method, based on the non-contact wafer flipping device, and illustrated with a 4-inch wafer, as shown in FIG. Figures 1 to 4 As shown, the method includes:

[0046] S101, rotating the finger cylinder 1 drives the wafer clamping robot 6 to move in the opposite direction and open, until the distance between the vertical clamping surfaces 602 on both sides is greater than the diameter of the wafer;

[0047] S102, the wafer removal robot carries the wafer and extends horizontally between the two vertical clamping surfaces 602;

[0048] S103, the wafer removal robot moves downward until the wafer is supported on the first supporting slope 601. Figure 3 (a)

[0049] S104, the rotating finger cylinder 1 drives the wafer clamping manipulators 6 on both sides to move toward each other, and the wafer moves along the first supporting inclined surface 601 to the vertical clamping surface 602 until the wafer is clamped between the two vertical clamping surfaces 602. Figure 3 (b)

[0050] S105, rotating the finger cylinder 1 drives the wafer clamping robot 6 to turn 180 degrees until the back of the wafer is horizontally facing upwards. Figure 3 (c)

[0051] S106, the rotating finger cylinder 1 drives the wafer clamping robot 6 to move in the opposite direction again, and the wafer slides downward along the second guide slope 603 until it reaches the third support slope 604. Figure 3 middle (d);

[0052] S107, the wafer removal robot extends horizontally to move the wafer upward until the wafer reaches between the two vertical clamping surfaces 602, and then removes the wafer;

[0053] S108, the rotating finger cylinder 1 drives the wafer clamping robot 6 to rotate in the opposite direction to the initial position to flip the next wafer.

[0054] The wafer clamping robot of the present invention does not contact the surface of the wafer, but only rests on the outer side of the wafer, and will not cause pollution, scratches and other unclean problems on the front and back of the wafer; the wafer slides along the inclined surface and falls into the clamping part of the wafer clamping robot, which can avoid the uncertainty caused by problems such as wafer tilting and shaking; the qualified rate of the wafer is improved, the damage rate of the wafer is reduced, and the production cost of semiconductor devices is reduced.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A non-contact wafer flipping method, characterized in that: Based on a non-contact wafer flipping device, the device includes: The rotating finger cylinder (1) drives the wafer clamping manipulator (6) to rotate in the opposite direction to the initial position to flip the next wafer; A rotating finger cylinder (1) having at least 180° of rotational freedom and relative movement freedom of the fingers (3); Two sets of wafer clamping supports (4) are symmetrically fixed on the two fingers (3) of the rotating finger cylinder (1); and Wafer clamping manipulators (6) are symmetrically connected to the wafer clamping support (4) to clamp the wafer to be turned over; the inner sides of the two wafer clamping manipulators (6) are respectively provided with arc grooves for clamping the edges of the wafer; The inner wall of the arc-shaped groove has a first supporting inclined surface (601), a vertical clamping surface (602), a second guiding inclined surface (603) and a third supporting inclined surface (604) which are connected in sequence along the width direction of the groove; wherein the inclination direction of the first supporting inclined surface (601) is opposite to the inclination direction of the second guiding inclined surface (603) and the third supporting inclined surface (604); the inclination angle of the second guiding inclined surface (603) is greater than the inclination angle of the third supporting inclined surface (604); the width of the vertical clamping surface (602) is greater than or equal to the thickness of the wafer; The method comprises: The rotating finger cylinder (1) drives the wafer clamping manipulator (6) to move in the opposite direction and open, until the distance between the vertical clamping surfaces (602) on both sides is greater than the diameter of the wafer; The wafer-taking robot carries the wafer and extends horizontally between the two vertical clamping surfaces (602); The wafer-taking robot moves downward until the wafer is supported on the first supporting inclined surface (601); The rotating finger cylinder (1) drives the wafer clamping manipulators (6) on both sides to move toward each other, and the wafer moves along the first supporting inclined surface (601) toward the vertical clamping surface (602) until the wafer is clamped between the two vertical clamping surfaces (602); The rotating finger cylinder (1) drives the wafer clamping robot (6) to turn 180 degrees until the back side of the wafer is horizontally facing upwards; The rotating finger cylinder (1) drives the wafer clamping manipulator (6) to move in the opposite direction again, and the wafer slides downward along the second guide slope (603) until it reaches the third supporting slope (604); The wafer taking robot extends horizontally to move the wafer upward until the wafer reaches between the two vertical clamping surfaces (602), and then moves the wafer out.

2. The non-contact wafer flipping method according to claim 1, wherein: The radial length of the second guiding inclined surface (603) along the arc-shaped groove is greater than the radial length of the third supporting inclined surface (604) along the arc-shaped groove.

3. The non-contact wafer flipping method according to claim 1, wherein: The inclination angle of the first supporting inclined surface (601) is: 0°<α<10°, and the inclination angle of the third supporting inclined surface (604) is: 0°<β<10°.

4. The non-contact wafer flipping method according to claim 1, wherein: The wafer clamping robot (6) has an arc-shaped structure.

5. The non-contact wafer flipping method according to claim 1, wherein: It also includes a buffer (5), which is arranged between the wafer clamping robot (6) and the wafer clamping support (4).

6. The non-contact wafer flipping method according to claim 5, wherein: The buffer (5) is an elastic rubber block connected between the wafer clamping robot (6) and the wafer clamping support (4).

7. The non-contact wafer flipping method according to claim 1, wherein: The wafer clamping support (4) comprises a finger (3) connecting section, an arc-shaped support section and a manipulator connecting section which are connected in sequence, wherein the finger (3) connecting section is connected in parallel to the outer side of the finger (3), and the manipulator connecting section is connected to the outer side of the wafer clamping manipulator (6) along the radial direction of the arc-shaped groove.

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