A centering mechanism for frame wafers

Abstract

The utility model relates to a kind of centering mechanism for frame wafer, including positioning base, driving device, clamping plate and two pairs of contact piece for directly contacting frame wafer, driving device is installed on positioning base, clamping plate is connected with the movement output end of driving device, for clamping frame wafer;Wherein one pair of contact piece is installed on clamping plate and located in the side of positioning base, another pair of contact piece is installed on the other side of positioning base relative to clamping plate;Driving device can drive clamping plate to move towards or away from, so that two pairs of contact piece can clamp or release two flat edges mutually parallel on frame wafer, realize the centering positioning of frame wafer in perpendicular to flat edge direction.The mechanism is innovatively used single-side driving, double-side clamping flat edge scheme, and combined with high-precision driving and low-friction anti-static contact piece, aims to solve the problem of traditional clamping mode slip, low precision, realize the centering positioning of high speed, high precision, high reliability to frame wafer.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging equipment technology, and in particular to a centering mechanism for frame wafers, which is a high-precision centering mechanism for clamping and positioning frame wafers. Background Technology

[0002] In semiconductor packaging production lines, before a frame wafer enters the next process (such as die bonding or wire bonding), it needs to be precisely positioned to a predetermined center position. This process is called alignment or pre-alignment. Traditional alignment mechanisms typically use a cylinder-driven linkage mechanism to clamp the arc edge of the frame to achieve alignment.

[0003] However, this traditional method has significant drawbacks: the rounded edges of the frame are smooth curved surfaces, which easily lead to slippage during clamping, resulting in poor positioning repeatability, typically only ±0.5mm or even lower, which is insufficient to meet the requirements of high-precision packaging processes. Slippage not only affects alignment accuracy but may also generate particulate matter due to friction, contaminating the wafer. Therefore, there is an urgent need for an alignment solution that can provide higher precision and more reliable clamping to solve the core problems of slippage and insufficient precision. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a centering mechanism for frame wafers. This mechanism innovatively adopts a single-sided drive and double-sided clamping straight edge scheme, combined with high-precision drive and low-friction anti-static contacts, aiming to solve the problems of slippage and low precision in traditional clamping methods, and achieve high-speed, high-precision, and high-reliability centering and positioning of frame wafers.

[0005] The above-mentioned utility model objective is achieved through the following technical solution:

[0006] A centering mechanism for a frame wafer includes a positioning base, a driving device, a clamping plate, and two pairs of contact elements for direct contact with the frame wafer. The driving device is mounted on the positioning base, and the clamping plate is connected to the motion output end of the driving device for clamping the frame wafer.

[0007] One pair of the contacts is mounted on the clamping plate and located on one side of the positioning base, and the other pair of contacts is mounted on the opposite side of the positioning base relative to the clamping plate;

[0008] The driving device can drive the clamping plates to move towards or away from each other, so that the two pairs of contact elements can clamp or release two parallel straight edges on the frame wafer, thereby achieving centering and positioning of the frame wafer in the direction perpendicular to the straight edges.

[0009] Four protrusions for supporting wafers are integrally formed and fixedly connected to the edge of the positioning base, and a PEek pad is detachably fixedly connected to the protrusion.

[0010] As a further technical solution of this utility model: the driving device is a high-precision slide cylinder.

[0011] As a further technical solution of this utility model: the high-precision slide cylinder is equipped with a solenoid valve and a speed control valve. The solenoid valve is used to control the clamping action of the high-precision slide cylinder, and the speed control valve is used to control the movement speed of the high-precision slide cylinder.

[0012] As a further technical solution of this utility model: the contact element is a cam follower, wherein a pair of two cam followers are rotatably connected to both ends of the clamping plate, and another pair of two cam followers are rotatably connected to the edge of the positioning base.

[0013] As a further technical solution of this utility model: the outer ring of the cam follower is made of antistatic engineering plastic.

[0014] As a further technical solution of this utility model: the antistatic engineering plastic is an antistatic PEEK material with a volume resistivity of 1×10⁻⁶. 6 Ω·cm to 1×10 9 Ω·cm.

[0015] As a further technical solution of this utility model, it also includes a detection unit and a signal amplification unit connected to the detection unit. The detection unit is used to detect whether the frame wafer is located at the preset position of the alignment mechanism. The signal amplification unit is used to amplify the detection signal of the detection unit and upload it to the PLC. After being collected and processed by the PLC, it is transmitted to the host computer system via a communication protocol.

[0016] As a further technical solution of this utility model: the detection unit is an optical fiber sensor, and the signal amplification unit is an optical fiber signal amplifier.

[0017] As a further technical solution of this utility model: the repeatability of the centering mechanism is ±0.1mm.

[0018] In summary, compared with the prior art, the present invention has at least one of the following beneficial technical effects:

[0019] 1. Extremely high centering accuracy: The "one moving and one stationary" layout clamps the flat edge, which is compact and eliminates the synchronization error that may exist in dual-side drive, fundamentally eliminating slippage and achieving a repeatability positioning accuracy of up to ±0.1mm.

[0020] 2. Simple and reliable structure: The single-sided drive design simplifies the air circuit and control system, reduces manufacturing costs and failure rate, and ensures uniform and stable clamping force.

[0021] 3. Anti-pollution and anti-static: The contact parts are preferably made of anti-static PEEK material cam follower, which greatly reduces friction and wear and the generation of particulate matter, and effectively prevents electrostatic damage to the wafer.

[0022] 4. Integration and Intelligence: It integrates a high-sensitivity fiber optic sensor and a signal amplifier. The detected signal is processed by the PLC and interacts with the host computer through a communication protocol, realizing safety monitoring and intelligent control. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of one side of this utility model.

[0024] Figure 2 This is a schematic diagram of the overall structure of the other side of this utility model.

[0025] Figure 3 This is a top view of the present invention.

[0026] Figure 4 This is a schematic diagram of the structure of this utility model in an unaligned state.

[0027] Figure 5 This is a schematic diagram of the structure of this utility model in the centering state.

[0028] Reference numerals: 1. Positioning base; 11. Boss; 12. PEEK pad; 13. Leveling hole; 2. Drive device; 21. Cylinder base; 22. Piston rod; 23. Sliding plate; 24. Hydraulic buffer; 3. Clamping plate; 4. Contact element; 5. Frame wafer; 51. Straight edge; 6. Solenoid valve; 7. Speed ​​control valve; 8. Detection unit; 9. Signal amplification unit. Detailed Implementation

[0029] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0030] In the description of this application, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] Example 1:

[0033] Reference Figures 1-5 This utility model discloses a centering mechanism for a frame wafer, comprising a positioning base 1, a driving device 2, a clamping plate 3, and two pairs of contact elements 4 for directly contacting the frame wafer 5. The driving device 2 is mounted on the positioning base 1, and the clamping plate 3 is connected to the motion output end of the driving device 2 for clamping the frame wafer 5. One pair of contact elements 4 is mounted on the clamping plate 3 and located on one side of the positioning base 1, and the other pair of contact elements 4 is mounted on the opposite side of the positioning base 1 relative to the clamping plate 3. The driving device 2 can drive the clamping plate 3 to move towards or away from each other, so that the two pairs of contact elements 4 can clamp or release two parallel straight edges 51 on the frame wafer 5, thereby achieving centering and positioning of the frame wafer 5 in the direction perpendicular to the straight edges 51.

[0034] Once the frame wafer 5 is placed on the centering station, the drive unit 2 operates, driving the clamping plate 3 to move towards the other pair of fixed contact members 4. The pair of contact members 4 mounted on the clamping plate 3 then move, working in conjunction with the pair of contact members 4 fixed on the base to clamp the two parallel straight edges 51 of the frame wafer 5 from both sides. Because it clamps the straight edges, and simultaneous clamping on both sides can be achieved by driving from one side, the risk of slippage on the curved surface is effectively avoided. By precisely controlling the stroke of the drive unit 2, the frame wafer 5 can be accurately positioned at the center in a direction perpendicular to the straight edges (such as the Y direction).

[0035] Reference Figure 1The drive unit 2 is a high-precision slide cylinder. The high-precision slide cylinder is equipped with a solenoid valve 6 and a speed control valve 7. The solenoid valve 6 is used to control the clamping action of the high-precision slide cylinder, and the speed control valve 7 is used to control the movement speed of the high-precision slide cylinder.

[0036] Reference Figure 2 In this embodiment, the high-precision slide cylinder consists of a cylinder base 21, two piston rods 22, and a sliding plate 23. The sliding plate 23 is slidably mounted on the slide rail of the cylinder base 21, and one end of the sliding plate 23 is fixedly connected to the clamping plate 3. The two piston rods 22 are disposed in the cylinder base 21, and their ends are connected to one end of the sliding plate 23. When the two piston rods 22 move synchronously, they push the sliding plate 23 to move back and forth on the slide rail of the cylinder base 21, thereby realizing the telescopic movement of the clamping plate 3. Furthermore, a hydraulic buffer 24 is installed on one side of the cylinder base 21, and the output shaft of the hydraulic buffer 24 is positioned facing the side wall of the clamping plate 3 to provide buffering force.

[0037] Contact element 4 is a cam follower, with one pair of cam followers rotatably connected to both ends of the clamping plate 3, and another pair of cam followers rotatably connected to the edge of the positioning base 1. The outer ring of the cam follower is made of antistatic engineering plastic. The antistatic engineering plastic is an antistatic PEEK material with a volume resistivity of 1×10⁻⁶. 6 Ω·cm to 1×10 9 Ω·cm.

[0038] Reference Figure 3 It also includes a detection unit 8 and a signal amplification unit 9 connected to the detection unit 8. The detection unit 8 is used to detect whether the frame wafer 5 is located at the preset position of the alignment mechanism. The signal amplification unit 9 is used to amplify the detection signal of the detection unit 8 and upload it to the PLC. After being acquired and processed by the PLC, it is transmitted to the host computer system via a communication protocol. In this embodiment, the detection unit 8 is a fiber optic sensor and the signal amplification unit 9 is a fiber optic signal amplifier.

[0039] Reference Figure 1 Four protrusions 11 for supporting the wafer are integrally formed and fixedly connected to the edge of the positioning base 1. A PEEK pad 12 is detachably fixedly connected to each protrusion 11. In this embodiment, the repeatability of the centering mechanism is ±0.1mm. The PEEK pad 12 is detachably fixed to the protrusion 11 by screws to support the frame wafer 5. A high-sensitivity fiber optic sensor, as a detection unit 8, is mounted on the positioning base 1. Its signal output is connected to a fiber optic signal amplifier (signal amplification unit 9), and the output of the fiber optic signal amplifier is connected to a PLC. In this embodiment, the positioning base 1 also has four leveling holes 13, with leveling screws threaded into the holes 13, facilitating the adjustment of the positioning base 1 to a horizontal state.

[0040] In this embodiment, the alignment mechanism is a dedicated alignment mechanism for 8-inch frame wafers, which has the advantages of high speed, high precision, high rigidity, high efficiency, and small size. The positioning base 1 is made of high-strength aluminum alloy, and all parts in contact with the frame wafer are made of anti-static PEEK material (anti-static resistance: 1×10⁻⁶). 6 —1×10 9 (Ω), effectively preventing electrostatic breakdown and electrostatic adsorption of the frame wafer. The moving parts use a high-precision slide cylinder with magnetic switches, achieving a repeatability accuracy of ±0.1mm. Equipped with a high-precision solenoid valve 6 and speed control valve 7, it allows for precise control of the clamping action and efficient adjustment of the clamping speed. A dedicated cam follower is used in the part that contacts the frame wafer during alignment. The cam follower has slight elasticity, solving the problem of traditional metal materials easily detaching under high load and high speed. It is corrosion-resistant, wear-resistant, and has a longer service life. While maintaining elasticity and wear resistance, it also improves hardness, making it suitable for high-precision operations and effectively reducing friction during frame wafer clamping.

[0041] In this embodiment, the alignment mechanism includes a high-sensitivity fiber optic sensor and fiber optic signal amplifier to accurately detect the position of the frame wafer, establishing program safety protection to safeguard the alignment mechanism, frame wafer, and wafer robot. It uses DC24V power supply, and the electrical interfaces feature quick-connect for convenient plug-and-play operation. The electrical signals on the alignment mechanism employ a modular design concept, enabling signals to be acquired and processed by the PLC and transmitted to the host computer system via a communication protocol. This question-and-answer signal interaction significantly saves storage space in the host computer system and improves processing speed.

[0042] The core innovation of this utility model lies in the adoption of a unique "one moving, one static" clamping layout and a clamping method based on the flat edge.

[0043] The mechanism mainly includes a positioning base 1, a driving device 2, a clamping plate 3, and two pairs of contact elements 4. The driving device 2 (such as a high-precision slide cylinder) is mounted on the positioning base 1. The clamping plate 3 is connected to the motion output end of the driving device 2 (such as the slide of the slide cylinder) and can be driven by the driving device 2 to perform linear motion.

[0044] The key lies in the arrangement of the two pairs of contact elements 4: one pair of contact elements 4 is mounted on the clamping plate 3 and moves with it; the other pair of contact elements 4 is directly mounted on the positioning base 1, on the side opposite to the clamping plate 3, and its position is fixed. These two pairs of contact elements 4 correspond to each other in space.

[0045] Reference Figure 4and Figure 5 Working principle: The robot transfers the frame wafer 5 to the centering mechanism and lowers it, where it is supported by four PEek pads 12, with its two parallel straight edges 51 roughly aligned with the contact pieces 4 on both sides. After the fiber optic sensor detects that the wafer is in place, the signal is amplified and sent to the PLC. The PLC controls the solenoid valve 6 to move, driving the high-precision slide cylinder to move the clamping plate 3 and the contact pieces 4 mounted on it towards the fixed contact pieces 4. Finally, the two pairs of contact pieces 4 work together to clamp the straight edges 51 of the frame wafer 5 from both sides, using the excellent positioning reference provided by the flat edges to accurately push it to the center position in the Y direction, with a repeatability accuracy of ±0.1mm. This utility model perfectly solves the core pain points of traditional centering mechanisms through a unique single-action structure and material optimization.

[0046] The implementation principle of this utility model is as follows: This utility model discloses a centering mechanism for frame wafers, including a positioning base 1, a driving device 2, a clamping plate 3, and two pairs of contact elements 4. Its innovation lies in: one pair of contact elements 4 is mounted on the clamping plate 3 and moves with it, while the other pair of contact elements 4 is fixed to the positioning base 1; the driving device 2 drives the clamping plate 3 to move, causing the two pairs of contact elements 4 to cooperate in clamping two parallel straight edges 51 on the frame wafer 5, achieving positioning. This "one moving, one stationary" layout combined with the flat edge clamping scheme completely avoids slippage, has a simple and compact structure, and achieves a repeatability positioning accuracy of up to ±0.1mm. The contact elements 4 adopt anti-static PEEK cam followers, which have the advantages of anti-static properties, low wear, and low contamination.

[0047] The embodiments described herein are preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape, and principle of this utility model should be included within the scope of protection of this utility model.

Claims

1. A centering mechanism for a frame wafer, characterized in that, It includes a positioning base (1), a driving device (2), a clamping plate (3), and two pairs of contact elements (4) for direct contact with the frame wafer (5). The driving device (2) is mounted on the positioning base (1), and the clamping plate (3) is connected to the motion output end of the driving device (2) for clamping the frame wafer (5). One pair of the contact elements (4) is mounted on the clamping plate (3) and located on one side of the positioning base (1), and the other pair of the contact elements (4) is mounted on the opposite side of the positioning base (1) relative to the clamping plate (3); The driving device (2) can drive the clamping plate (3) to move towards each other or away from each other, so that the two pairs of contact members (4) can clamp or release the two parallel straight edges (51) on the frame wafer (5), thereby achieving the centering and positioning of the frame wafer (5) in the direction perpendicular to the straight edges (51). The positioning base (1) has four protrusions (11) integrally formed and fixedly connected on its edge for supporting the wafer, and a peek pad (12) is detachably fixedly connected to the protrusion (11).

2. The centering mechanism for a frame wafer according to claim 1, characterized in that, The drive device (2) is a high-precision slide cylinder.

3. The centering mechanism for a frame wafer according to claim 2, characterized in that, The high-precision slide cylinder is equipped with a solenoid valve (6) and a speed control valve (7). The solenoid valve (6) is used to control the clamping action of the high-precision slide cylinder, and the speed control valve (7) is used to control the movement speed of the high-precision slide cylinder.

4. The alignment mechanism for a frame wafer according to claim 1, characterized in that, The contact element (4) is a cam follower, wherein a pair of two cam followers are rotatably connected to both ends of the clamping plate (3), and another pair of two cam followers are rotatably connected to the edge of the positioning base (1).

5. A centering mechanism for a frame wafer according to claim 4, characterized in that, The outer ring of the cam follower is made of antistatic engineering plastic.

6. A centering mechanism for a frame wafer according to claim 5, characterized in that, The antistatic engineering plastic is an antistatic PEEK material with a volume resistivity of 1×10⁻⁶. 6 Ω·cm to 1×10 9 Ω·cm.

7. The alignment mechanism for a frame wafer according to claim 1, characterized in that, It also includes a detection unit (8) and a signal amplification unit (9) connected to the detection unit (8). The detection unit (8) is used to detect whether the frame wafer (5) is located at the preset position of the centering mechanism. The signal amplification unit (9) is used to amplify the detection signal of the detection unit (8) and upload it to the PLC. After being collected and processed by the PLC, it is transmitted to the host computer system via a communication protocol.

8. A centering mechanism for a frame wafer according to claim 7, characterized in that, The detection unit (8) is an optical fiber sensor, and the signal amplification unit (9) is an optical fiber signal amplifier.

9. A centering mechanism for a frame wafer according to claim 1, characterized in that, The repeatability of the centering mechanism is ±0.1mm.

Images