An automatic clamping structure for a semiconductor wafer transportation system

Abstract

The application relates to the technical field of mechanical manufacturing, and discloses an automatic clamping structure for a semiconductor wafer conveying system, which comprises a bearing table for bearing a wafer, and an elastic telescopic mechanism arranged on one side of the bearing table, wherein the elastic telescopic mechanism adopts a rod-shaped structure, the axial center line of the rod-shaped structure passes the center of the wafer, the wafer is clamped on the bearing table or released from the clamping through elastic telescoping, the clamping force on the wafer can be adjusted, the elastic telescopic mechanism is further connected with a detection mechanism, and the detection mechanism moves synchronously with the elastic telescopic mechanism to detect whether the wafer is being clamped. With the aid of the elastic telescopic mechanism, the clamping force of the elastic telescopic mechanism can be adjusted according to the specification requirements of the wafer, the conveying requirements of wafers of various specifications can be met, the application range is wider, the practicability is stronger, the detection function is provided to determine whether the wafer on the bearing table is being clamped, the action state of the clamping structure can be more comprehensively fed back, and the intelligent degree is higher.

Description

Technical Field

[0001] This invention relates to the field of mechanical manufacturing technology, and more specifically to an automatic clamping structure for a semiconductor wafer transport system. Background Technology

[0002] In the semiconductor transport field, semiconductor robots are used to transport wafers at various workstations. The end effector of the third arm of a semiconductor robot generally adopts three wafer fixation methods: clamping, adsorption, and friction. Traditional clamping methods sometimes use pneumatic cylinders and sometimes micro electric cylinders. Each method has its own advantages and disadvantages. Pneumatic cylinders have a simple structure, small size, and low cost, but they can contaminate the wafers. Even with clean cylinders, leakage is inevitable after prolonged operation, leading to wafer contamination. Electric cylinders, on the other hand, have a complex structure, large size, and high cost, involving too many circuits. Furthermore, both of these drive methods share the disadvantage of fixed clamping force, which is not compatible with various wafer types. For example, using the clamping force of a standard wafer to transport Taiko wafers and ultra-thin wafers can easily cause breakage. Using a smaller clamping force to transport standard wafers will result in a lower cycle time. Summary of the Invention

[0003] This invention provides an automatic clamping structure for semiconductor wafer transport systems, which solves the technical problems of wafer contamination and non-adjustable clamping force caused by traditional clamping cylinder drive methods.

[0004] This invention can be achieved through the following technical solutions:

[0005] An automated clamping structure for a semiconductor wafer transport system includes a carrier stage for carrying the wafer. An elastic telescopic mechanism is provided on one side of the carrier stage. The elastic telescopic mechanism has a rod-like structure, with its axial centerline passing through the center of the wafer. Through elastic telescopic movement, it clamps or releases the wafer from the carrier stage and can adjust the clamping force on the wafer.

[0006] The elastic telescopic mechanism is also connected to a detection mechanism, which moves synchronously with the elastic telescopic mechanism to detect whether the wafer is being clamped.

[0007] Furthermore, the elastic telescopic mechanism is driven by a cylinder, which is located on one side of the rod-shaped structure. Its piston rod is connected to the rod-shaped structure through a Z-shaped adapter plate, and the axial center line of the piston rod is parallel to the axial center line of the rod-shaped structure.

[0008] The detection mechanism includes a photoelectric sensor and a light-shielding plate that works with it. The photoelectric sensor is located on the other side of the rod-shaped structure, and its detection end is U-shaped. The direction of its opening is parallel to the axial center line of the rod-shaped structure. One end of the light-shielding plate is connected to the rod-shaped structure, and the other end is inserted into the U-shaped structure of the photoelectric sensor. When the wafer is clamped, the light-shielding plate is in the middle position of the U-shaped structure.

[0009] Furthermore, the elastic telescopic mechanism includes a push rod, a spring seat, and an adjusting rod connected in sequence, with their axial center lines collinear and passing through the center of the wafer. A cavity that mates with the spring is provided inside the spring seat. One end of the push rod passes through the cavity and is connected to one end of the spring. The other end of the push rod passes through the first linear bearing and is connected to the push block.

[0010] One end of the adjusting rod passes through the cavity and the other end is connected to the other end of the spring. The connection between the adjusting rod and the cavity is made by thread. The other end of the adjusting rod is fitted with a second linear bearing. By changing the length of the adjusting rod screwed into the spring seat, the rebound force of the spring is adjusted. The spring is always in a compressed state.

[0011] The surface of the spring seat is connected to one end of the Z-shaped adapter plate, and the other end of the Z-shaped adapter plate is connected to the piston rod of the cylinder. The axial center line of the piston rod is parallel to the axial center lines of the push rod, the spring seat, and the adjusting rod.

[0012] The cylinder is used to drive the Z-shaped adapter plate, along with the spring seat, push rod, and adjusting rod, to reciprocate along the axial direction of the elastic telescopic mechanism via the piston rod, thereby causing the push block to extend or retract, so as to achieve wafer clamping or release.

[0013] Furthermore, the spring seat includes a cylindrical cavity, and one end of it connected to the adjusting rod is provided with an internal thread.

[0014] Furthermore, the light-shielding plate has an L-shaped structure, with one end connected to the push rod and the other end provided with a tongue extending into the U-shaped structure.

[0015] Furthermore, multiple stops are spaced apart on the opposite side of the pusher block on the support platform. These stops cooperate with the wafer and, together with the pusher block, clamp the wafer.

[0016] The beneficial technical effects of this invention are as follows:

[0017] The existing cylinder-driven wafer clamping structure is optimized by changing the direction of the cylinder output end and using a low-dust-generating linear bearing as a guide support to avoid the generation of process particles and solve the contamination problem.

[0018] The adjustable rod inside the elastic telescopic mechanism changes the spring compression length to achieve adjustable clamping force, making it suitable for clamping various wafers such as standard wafers, ultra-thin wafers, and Taiko wafers. At the same time, the elastic clamping performance of the elastic telescopic mechanism makes it adaptive, ensuring that the wafer can be clamped tightly but not excessively.

[0019] In addition, the entire device has a simple structure, is easy to maintain, and is easy to promote and apply. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the overall internal structure of the present invention;

[0022] Figure 3 This is a schematic diagram of the rod-shaped structure of the elastic telescopic mechanism of the present invention;

[0023] Figure 4 For the present invention Figure 2 Enlarged schematic diagram of part of the image;

[0024] Among them, 1-cylinder, 2-Z-shaped adapter plate, 3-photoelectric sensor, 4-sunshade plate, 5-push rod, 6-spring seat, 7-adjusting rod, 8-first linear bearing, 9-push block, 10-second linear bearing, 11-stop block. Detailed Implementation

[0025] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings and preferred embodiments.

[0026] like Figure 1 As shown, this invention provides an automatic clamping structure for a semiconductor wafer transport system, including a carrier platform for carrying the wafer. An elastic telescopic mechanism is provided on one side of the carrier platform. This elastic telescopic mechanism has a rod-like structure, with its axial centerline passing through the center of the wafer. It clamps or releases the wafer on the carrier platform through elastic telescopic movement and can adjust the clamping force on the wafer. The elastic telescopic mechanism is also connected to a detection mechanism, which moves synchronously with the elastic telescopic mechanism to detect whether the wafer is being clamped. Thus, the clamping force applied to the wafer has a certain degree of adaptability, ensuring that the wafer is clamped tightly without being over-clamped. Furthermore, the clamping force of the elastic telescopic mechanism can be adjusted according to the wafer's specifications to meet the handling requirements of wafers of various sizes, thus broadening its application range and increasing its practicality. In addition, the automatic clamping structure of this invention also has a detection function to determine whether a wafer is being clamped on the carrier platform, providing more comprehensive feedback on the operating status of the clamping structure and increasing its level of intelligence.

[0027] Specifically as follows:

[0028] The elastic telescopic mechanism is driven by a cylinder. The cylinder 1 is located on one side of the rod-shaped structure. Its piston rod is connected to the rod-shaped structure through a Z-shaped adapter plate 2. The axial center line of the piston rod is parallel to the axial center line of the rod-shaped structure. With the indirect connection of the Z-shaped adapter plate 2, the output end of the cylinder 1 is kept as far away from the wafer as possible, reducing the possibility of wafer contamination. At the same time, it can also reduce the volume of the overall structure, make full use of space, and facilitate connection with the robotic arm of the wafer handling robot.

[0029] The testing mechanism includes a photoelectric sensor 3 and a light-shielding plate 4 that works with it. The photoelectric sensor 3 is located on the other side of the rod-shaped structure, and its detection end is U-shaped. The direction of its opening is parallel to the axial center line of the rod-shaped structure. One end of the light-shielding plate 4 is connected to the rod-shaped structure, and the other end is inserted into the U-shaped structure of the photoelectric sensor 3. When the wafer is clamped, the light-shielding plate 4 is in the middle of the U-shaped structure. The light-shielding plate 4 can be designed as an L-shaped structure, with one end connected to the rod-shaped structure such as a push rod, and the other end provided with a tongue extending into the U-shaped structure for easy shielding.

[0030] Considering the detection principle of photoelectric sensor 3, when the wafer is clamped, the light shield 4 blocks the detection light and outputs a feedback signal. Due to the elasticity of the elastic telescopic mechanism, the actual extension length of the push block of the elastic telescopic mechanism is greater than the extension length when there is a wafer blocking it. Therefore, when there is no wafer on the carrier, the light shield 4 will continue to move beyond the blocking position when there is a wafer under the drive of the elastic telescopic mechanism. At this time, a feedback signal can still be output. Therefore, the position where the light shield 4 detects the wafer should be set as close as possible to the middle of the U-shaped structure to avoid damage to the light shield when it is accidentally triggered.

[0031] The elastic telescopic mechanism includes a push rod 5, a spring seat 6, and an adjusting rod 7 connected in sequence. Their axial center lines are collinear and pass through the center of the wafer. A cavity, which can be cylindrical, is provided inside the spring seat 6 to mate with the spring. One end of the push rod 5 passes through the cavity and connects to one end of the spring, allowing for a clearance fit to ensure smooth movement of the push rod 5. The other end of the push rod 5 passes through a first linear bearing 8 and connects to a push block 9. One end of the adjusting rod 7 passes through the cavity and connects to the other end of the spring. The connection between the adjusting rod and the cavity is threaded, facilitating adjustment of the spring's compression. A second linear bearing 10 is fitted onto the other end of the adjusting rod. By changing the length of the adjusting rod 7 screwed into the spring seat, the spring's rebound force is adjusted. The entire process... The spring is always compressed to ensure sufficient clamping force. Simultaneously, the first linear bearing 8 and the second linear bearing 10 both act as guides, ensuring the directional movement of the push rod 5 and the adjusting rod 7. The surface of the spring seat 6 is connected to one end of the Z-shaped adapter plate 2, and the other end of the Z-shaped adapter plate 2 is connected to the piston rod of the cylinder. Both can be threaded for easy installation. The axial centerline of the piston rod is parallel to the axial centerlines of the push rod 5, the spring seat 6, and the adjusting rod 7. Thus, driven by the cylinder 1, the piston rod drives the Z-shaped adapter plate 2, along with the spring seat 6, the push rod 5, and the adjusting rod 7, to reciprocate along the axial direction of the elastic telescopic mechanism, thereby causing the push block 9 to extend or retract, achieving wafer clamping or release.

[0032] For clamping purposes, multiple stops 11 can be spaced apart on the opposite side of the support platform from the pusher block 9. These stops are all designed to cooperate with the wafer and can be stepped structures. The pusher block 9 can be circular or arc-shaped. As the pusher block 9 extends, it pushes the wafer toward the stop 11, so that the wafer can be clamped together with the pusher block 9.

[0033] Detailed structure is attached. Figure 2 The third arm is fixed to the second arm of the wafer handling robot. The first linear bearing 8 and the second linear bearing 10 are fixed to the third arm and serve as guides for the push rod 5 and the adjusting rod 7. The detection mechanism is fixed to the third arm and is used to detect whether a wafer is being clamped. The stop block 11 is fixed to the end finger. The Z-shaped adapter plate 2 is used to connect the cylinder 1 and the rod-shaped structure. The adjusting rod 7 and the push rod 5 are connected by a spring and a spring seat. When the cylinder 1 moves, it can drive the push block to move, thereby achieving wafer clamping. The air circuit assembly is used for the transmission of compressed air and the adjustment of the movement speed of the cylinder 1.

[0034] The principle of clamping force adjustment is as follows: Figure 3The spring is fixed inside the spring seat 6, and the end of the spring contacts the adjusting rod 7. One end of the adjusting rod 7 is externally threaded, and one end of the spring seat 6 is internally threaded, so they can be screwed on to change the compression length of the spring and thus change the magnitude of the spring thrust. The other end of the adjusting rod 7 is a smooth shaft, which can be guided by a linear bearing. The spring seat 6 is connected to the adapter plate, and can be driven to move when the cylinder 1 is activated.

[0035] Push block 9 is fixed on push rod 5. Push rod 5 is guided by first linear bearing 8. The other end of push rod 5 is in contact with the front end of spring. When the spring force changes, the force acting on push rod 5 also changes, thereby changing the magnitude of clamping force and thus achieving compatibility with different wafers.

[0036] The method for achieving contamination-free wafer clamping is as follows: Figure 4 The piston rod of cylinder 1 is connected to spring seat 6 via Z-shaped adapter plate 2, so that the output end of cylinder 1 is not directly facing the wafer. Even if a small amount of particles are ejected from the outlet, they will be blocked inside the third arm. The part directly facing the wafer is guided by a linear bearing. The linear bearing is of low dust generation type and will not produce too many particles.

[0037] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples. Various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. Therefore, the scope of protection of the present invention is defined by the appended claims.

Claims

1. An automatic clamping structure for a semiconductor wafer transport system, characterized in that: The device includes a support platform for holding a wafer, and an elastic telescopic mechanism is provided on one side of the support platform. The elastic telescopic mechanism adopts a rod-shaped structure, and its axial center line passes through the center of the wafer. It can clamp or release the wafer on the support platform through elastic telescopic movement, and can adjust the clamping force on the wafer. The elastic telescopic mechanism is also connected to a detection mechanism, which moves synchronously with the elastic telescopic mechanism to detect whether the wafer is being clamped. The elastic telescopic mechanism is driven by a cylinder, which is located on one side of the rod-shaped structure. Its piston rod is connected to the rod-shaped structure through a Z-shaped adapter plate, and the axial center line of the piston rod is parallel to the axial center line of the rod-shaped structure. The elastic telescopic mechanism includes a push rod, a spring seat, and an adjusting rod connected in sequence. Their axial center lines are collinear and pass through the center of the wafer. A cavity that mates with the spring is provided inside the spring seat. One end of the push rod passes through the cavity and connects to one end of the spring. The other end of the push rod passes through a first linear bearing and connects to the push block. One end of the adjusting rod passes through the cavity and connects to the other end of the spring. The connection between the adjusting rod and the cavity is threaded. The other end of the adjusting rod is fitted with a second linear bearing. By changing the length of the adjusting rod screwed into the spring seat, the rebound force of the spring is adjusted, and the spring is always in a compressed state. The surface of the spring seat is connected to one end of a Z-shaped adapter plate. The other end of the Z-shaped adapter plate is connected to the piston rod of a cylinder. The axial center line of the piston rod is parallel to the axial center lines of the push rod, spring seat, and adjusting rod. The cylinder is used to drive the Z-shaped adapter plate, along with the spring seat, push rod, and adjusting rod, to reciprocate along the axial direction of the elastic telescopic mechanism via the piston rod, thereby causing the push block to extend or retract, so as to achieve wafer clamping or release.

2. The automatic clamping structure for a semiconductor wafer transport system according to claim 1, characterized in that: The cavity of the spring seat is a cylindrical structure, and the end that connects to the adjusting rod is provided with an internal thread.

3. The automatic clamping structure for a semiconductor wafer transport system according to claim 1, characterized in that: On the opposite side of the support platform from the pusher block, there are multiple stops at intervals. These stops cooperate with the wafer and, together with the pusher block, clamp the wafer.

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