Wafer lifting structure

Abstract

The invention discloses a wafer lifting structure which comprises at least one lifting arm, an arc-shaped notch part defined by the lifting arm, an opening end, a penetrating channel extending along the central axis of the arc-shaped notch part, and a wafer limiting detection unit, the inner diameter of the arc-shaped notch part is matched with the outer diameter of a wafer, and the width of the opening end is smaller than the outer diameter of the wafer. The wafer limiting detection unit is movably arranged in the through channel, at least part of the wafer limiting detection unit can penetrate through the lifting arm in the second direction to stretch into the arc-shaped notch part to abut against the wafer, the through channel is provided with a limiting pipeline, and part of the wafer limiting detection unit is located in the limiting pipeline to form limiting fit of the wafer limiting detection unit and the limiting pipeline in the first direction. The first direction is perpendicular to or tends to be perpendicular to the second direction. The wafer limiting detection unit is movably arranged in the through channel, so that the wafer limiting detection unit not only can play a role in detecting whether the wafer exists or not, but also can be matched with the lifting arm to stably clamp the wafer, and two-in-one of stable clamping and wafer detection of the wafer is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor integrated circuit chip manufacturing, and in particular relates to a wafer pulling structure. Background Art

[0002] In the process of manufacturing semiconductor integrated circuit chips, wafers need to go through multiple cleaning processes to remove surface contaminants. For example, the cleaning unit in the chemical mechanical planarization (CMP) equipment needs to go through multiple cleaning processes during operation, and different processes are completed between different modules. Therefore, a wafer transfer arm is required to move the wafer between modules and ensure stable and efficient wafer placement.

[0003] Currently, the presence or absence of a wafer is usually determined by detecting the obstruction of the optical path during the horizontal movement of the wafer. This method is usually suitable for application scenarios with a single handle. The application scenario with multiple handles has the problem of sharing the optical path, the detection is not accurate enough, and real-time detection cannot be achieved. In addition, when used in the cleaning process, optical detection is easily affected by the humid environment and the presence of droplets on the detection device, resulting in a very high probability of false detection in optical detection. For example, the Chinese invention patent named Wafer Clamping Arm (patent number CN119361497A) improves the sensor bracket of the wafer clamping arm to adopt a fixed design (both the receiving and transmitting brackets are large hydrophobic angle structures), the sensor is clamped by a fixed bracket, the sensor bracket is fixed to the clamping arm, and the hydrophobic structure is used to reduce the interference of water droplets, but false detection cannot be avoided.

[0004] Of course, optical sensors are not the only detection method. For example, the Chinese invention patent named "A wafer transfer robot and cleaning device" (patent number CN222021614U) mentions that frequency sensors, tension sensors, and weighing sensors can be used, but it is not difficult to see that the traditional sensor placement positions are fixed. However, there are some problems with fixed positions: ① Different process environments (such as changes in liquid level in wet processes) require sensors to flexibly adjust their positions to avoid interference (such as droplet sputtering). Fixed designs are difficult to dynamically adapt to environmental changes, which may reduce detection reliability. ② In addition, fixed sensors cannot adjust the detection angle and distance according to changes in wafer size or position, which may lead to detection blind spots. For example, when the wafer position shifts during the pulling process, the fixed sensor may not cover the entire area. ③ In addition, the dynamic swing of the wafer during the pulling process may cause the sensor signal to be intermittent. If the sensor is movable, the wafer position can be tracked in real time to optimize the detection path, but the fixed design cannot achieve this function.

[0005] In addition, traditional cleaning equipment usually uses a wafer transfer arm with an arc-shaped notch to transfer wafers between various cleaning or drying units. However, this type of wafer transfer arm with an arc-shaped notch is prone to offset or shaking when clamping the wafer, causing the wafer to shift during the transfer process, affecting the subsequent cleaning effect. In order to solve this problem, the improvement proposed in the prior art is to use a special clamping mechanism to enhance the ability to fix the wafer by adjusting the clamping force. However, this increases the complexity of the system, makes the structural stability of the robot worse, and the excessive contact area of ​​the wafer leads to the possibility of contamination, and cannot fundamentally solve the problem of wafer offset. Summary of the invention

[0006] In order to overcome the deficiencies of the prior art, the present invention provides a wafer lifting structure, which can firmly clamp the wafer by utilizing the cooperation of a shoulder pole wafer limit detection unit and a lifting arm, and can also detect in real time whether the wafer is firmly clamped.

[0007] The technical solution adopted by the present invention to solve its technical problems is: a wafer lifting structure, comprising at least one lifting arm, an arc-shaped notch portion formed by the lifting arm, and an open end, the inner diameter of the arc-shaped notch portion is adapted to the outer diameter of the wafer, and the width of the open end is smaller than the outer diameter of the wafer, and also comprises a through channel extending along the central axis of the arc-shaped notch portion, and a wafer limit detection unit, the wafer limit detection unit is movably arranged in the through channel, and at least a part of it can pass through the lifting arm along a second direction and extend into the arc-shaped notch portion to resist the wafer, the through channel has a limiting pipe, and part of the wafer limit detection unit is located in the limiting pipe to form a limiting cooperation between the two in a first direction, and the first direction and the second direction are perpendicular or tend to be perpendicular.

[0008] Furthermore, the wafer limit detection unit includes a shoulder pole piece movably arranged in the through channel, and a sensing piece connected to the shoulder pole piece. The shoulder pole piece can pass through the lifting arm and extend into the arc-shaped notch portion to abut against the wafer. The sensing piece is used to sense whether the lifting arm clamps the wafer.

[0009] Furthermore, the sensing component is arranged at the end of the shoulder pole component and is used to sense whether the shoulder pole component is in contact with the wafer.

[0010] Furthermore, the sensing element is arranged on the side of the shoulder pole member, and is used to sense the relative movement distance of the shoulder pole member relative to the lifting arm, and the through channel has an expanded diameter area for accommodating the sensing element.

[0011] Furthermore, the end of the shoulder pole is connected to a contact terminal, which has a receiving groove, and the opposite side walls of the receiving groove are in a flared cone shape.

[0012] Furthermore, a second mounting groove for accommodating the contact terminal is provided between the lifting arms.

[0013] Furthermore, the moving path of the shoulder pole coincides with or tends to coincide with the center line of the arc-shaped notch; the limiting pipe and part of the wafer limiting detection unit form a limiting fit in the third direction so that the shoulder pole is located in the plane where the arc-shaped notch is located.

[0014] Furthermore, the shoulder pole has at least a first stroke and a second stroke. When the shoulder pole moves in the first stroke, it abuts against the outer wall of the wafer to cooperate with the lifting arm to clamp the wafer. The second stroke is greater than the first stroke.

[0015] Furthermore, it also includes a base, and the lifting arm is connected to the base; the base is connected to a limiting member, and the shoulder pole is coaxially and movably connected to the limiting member.

[0016] Furthermore, the lifting arm has a first installation groove, and the limiting member is located in the first installation groove.

[0017] Furthermore, the shoulder pole member and the limiting member are parts of the cylinder.

[0018] The beneficial effects of the present invention are: 1) the wafer limit detection unit is movably arranged in the through channel, so that the wafer limit detection unit can not only play the function of detecting the presence or absence of the wafer, but also can cooperate with the lifting arm to firmly clamp the wafer, thereby realizing the two-in-one of firmly clamping the wafer and detecting the wafer; 2) a through channel is arranged, and the wafer limit detection unit is movably installed in the through channel, which will not occupy the extra space of the wafer lifting structure, nor does it need to make excessive changes to the existing wafer lifting structure, and reduces the exposure of the wafer limit detection unit to the environment, reducing the risk of interference with peripheral equipment; 3) the through channel is designed with a limit pipe, which can effectively prevent the wafer limit detection unit from shifting in multiple directions such as lateral shift; 4) the cooperation of the shoulder pole and the sensor can not only clamp the wafer to prevent it from shaking, but also detect the presence or absence of the wafer in real time, and judge whether the wafer is firmly clamped by the lifting structure. 5) The shoulder pole and the open end cooperate to realize three-point stable clamping of the wafer. After the wafer is clamped, it can be used for lifting in the vertical direction, and can also be used for horizontal flipping and other movements at various angles and directions, which makes the wafer clamping more flexible; 6) The shoulder pole cooperates with the wafer to effectively prevent the wafer from falling off and reduce the risk of damage to the wafer during transportation; 7) The sensor can be set in various positions, and the sensor can be set in multiple positions to detect the presence of the wafer, which increases the timeliness of the detection; 8) The through channel and the wafer limit detection unit are located in the middle of the lifting arm to avoid vibration or fatigue fracture of the lifting arm caused by eccentric loads. The through channel is convenient for integrating protective structures such as waterproof coatings to avoid chemical liquid penetration and improve reliability in a wet environment; 9) The upper end of the shoulder pole carries a connector and the lower end carries a contact terminal, so that the shoulder pole plays the role of a shoulder pole with objects carried at both ends and limited in the middle. The sensing part is arranged on the side of the shoulder pole for easy debugging; 10) The contact end is arranged to firmly clamp the wafer while preventing the front side of the wafer from being scratched. At the same time, the contact end has a flared conical receiving groove to facilitate the introduction of the wafer, that is, to facilitate the clamping of the wafer; 11) The limiter and the shoulder pole can be a cylinder structure, which is convenient for material selection and reduces processing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a front view of the present invention, in which a wafer is clamped.

[0020] Figure 2 It is a cross-sectional view of the present invention, at which a wafer is clamped.

[0021] Figure 3 The three-dimensional Figure 1 , at this time the wafer is clamped.

[0022] Figure 4 The three-dimensional Figure 2 , at this time the wafer is clamped.

[0023] Figure 5 The three-dimensional Figure 3 .

[0024] Figure 6 The three-dimensional Figure 4 .

[0025] Figure 7 for Figure 6 A magnified view of the structure in Figure 2.

[0026] Among them, 1-lifting arm, 11-second mounting groove, 12-first mounting groove, 2-arc-shaped notch, 3-open end, 4-wafer, 5-pole piece, 51-contact end, 52-accommodating groove, 6-sensing piece, 7-base, 71-limiting piece, 8-through channel, 81-limiting pipe, 82-expansion area, 9-wafer limit detection unit. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] A wafer lifting structure includes at least one lifting arm 1, an arc-shaped notch 2 formed by the lifting arm 1, and an open end 3. The inner diameter of the arc-shaped notch 2 is adapted to the outer diameter of the wafer 4 to be clamped, and the adaptation here means that the wafer 4 can pass through the arc-shaped notch 2. The width of the open end 3 is smaller than the outer diameter of the wafer 4, so that when the wafer 4 enters the plane where the arc-shaped notch 2 is located, the wafer lifting structure moves up, or the wafer 4 moves down, so that the center of the wafer 4 is located below the center of the arc-shaped notch 2, and the wafer 4 is hung at the open end 3. At this time, the wafer lifting structure can move synchronously with the wafer 4.

[0029] like Figure 2 As shown, the wafer lifting structure also includes a through channel 8 extending along the central axis of the arc-shaped notch portion 2, and a wafer limit detection unit 9. The wafer limit detection unit 9 is movably arranged in the through channel 8, and at least a portion of the wafer limit detection unit 9 can pass through the lifting arm 1 along the second direction and extend into the arc-shaped notch portion 2, thereby abutting against the wafer 4. Here, the second direction is parallel to the central axis direction of the arc-shaped notch portion 2.

[0030] The through channel 8 has a limiting pipe 81, and part of the wafer limiting detection unit 9 is located in the limiting pipe 81, thereby forming a limiting fit between the wafer limiting detection unit 9 and the limiting pipe 81, specifically a limiting fit in a first direction, and the first direction and the second direction are perpendicular or tend to be perpendicular. In other words, when the limiting pipe 81 is in the shape of a hollow pipe, its inner diameter is equal to the outer diameter of part of the wafer limiting detection unit 9, so that the wafer limiting detection unit 9 will not shake laterally at will. The limiting pipe 81 and part of the wafer limiting detection unit 9 form a limiting fit in a third direction, where the third direction is perpendicular to both the first direction and the second direction, that is, Figure 2 The direction perpendicular to the paper plane is made such that the shoulder pole member 5 is located in the plane where the arc-shaped notch portion 2 is located, and the wafer limit detection unit 9 will not be offset in the direction perpendicular to the paper plane.

[0031] The inside of the through channel 8 may be coated with a waterproof coating to prevent chemical liquids from penetrating into the through channel 8, thereby preventing the shoulder pole 5 from moving up and down in the through channel 8 with liquid in a wet environment, thereby improving the stability of operation in a wet environment.

[0032] like Figure 1-Figure 6 As shown, in this embodiment, the number of the lifting arm 1 is one, which is an integrated rigid structure. The wafer limit detection unit 9 includes a shoulder pole 5 movably arranged in the through channel 8 and movable relative to the lifting arm 1, and a sensing member 6 connected to the shoulder pole 5. The shoulder pole 5 can pass through the lifting arm 1 and extend into the arc-shaped notch 2 so as to abut against the wafer 4, and the sensing member 6 is used to sense whether the lifting arm 1 holds the wafer 4.

[0033] Specifically, the moving path of the shoulder pole 5 coincides with or tends to coincide with the center line of the arc-shaped notch 2. Figure 1 As shown, the center line of the arc-shaped notch 2 is L, which passes through the center of the clamped wafer 4, and the center line of the shoulder pole 5 also coincides with the L line. Figure 1 Taking the direction shown as an example, the shoulder pole 5 moves up and down along the L line.

[0034] There are many optional locations for the sensor 6. For example, the sensor 6 can be set at the end of the shoulder pole 5 to sense whether the shoulder pole 5 is against the wafer 4. Figure 6 , Figure 7 As shown, the sensing member 6 is arranged at the lower end of the shoulder pole member 5 (the sensing member 6 marked in the figure is the approximate setting position). When the lower end of the shoulder pole member 5 abuts against the side wall of the wafer 4, the sensing member 6 senses that the shoulder pole member 5 has abutted against the wafer 4, and obtains a signal that the shoulder pole member 5 clamps the wafer 4.

[0035] like Figure 1-Figure 3As shown, the sensing member 6 can also be arranged on the side of the shoulder pole 5 to sense the relative movement distance of the shoulder pole 5 relative to the lifting arm 1. The through channel 8 has an expanded diameter area 82 for accommodating the sensing member 6. In other words, the lateral width of the expanded diameter area 82 is greater than the inner diameter of the limiting pipe 81, thereby limiting the lateral displacement of the wafer limiting detection unit 9 and providing space for the installation of the sensing member 6. Of course, the specific position where the sensing member 6 is arranged on the side of the shoulder pole 5 is optional and is not limited. Specifically, the shoulder pole 5 has at least a first stroke and a second stroke. When the shoulder pole 5 moves in the first stroke, it abuts against the outer wall of the wafer 4, thereby cooperating with the lifting arm 1 to clamp the wafer 4, realizing three-point clamping of the wafer 4, and the clamping is more stable. The above-mentioned first stroke is the distance between the arc-shaped notch portion 2 and the outer wall of the wafer 4 when the wafer 4 is hung at the opening end 3.

[0036] When the pole 5 moves in the second stroke, since the second stroke is greater than the first stroke, that is, the sensing member 6 senses the difference between the second stroke and the first stroke, it means that the wafer 4 is not hung on the opening end 3 at this time, and the sensing member 6 obtains a signal that the pole 5 does not clamp the wafer 4. Of course, the first stroke is specifically the distance between the end of the pole 5 and the outer wall of the wafer 4 when the wafer 4 is hung on the opening end 3. There is no specific restriction on the first stroke, but it is only for the purpose of explaining that the pole 5 and the wafer 4 are against each other in the first stroke, and the pole 5 can continue to move a greater distance relative to the first stroke because it is not hindered by the wafer 4 in the second stroke.

[0037] Of course, the sensing element 6 may be provided at the end of the shoulder pole 5 and also at the side of the shoulder pole 5, without any specific limitation.

[0038] In order to ensure that the pole 5 and the wafer 4 are firmly clamped, a contact terminal 51 is connected to the end of the pole 5. Figure 7 As shown, the contact terminal 51 has a receiving groove 52, and the opposite side walls of the receiving groove 52 are in a flared cone shape. The side walls of the wafer 4 can abut against the top surface of the receiving groove 52, but the surface of the wafer 4 will not contact the side walls of the receiving groove 52, ensuring that the surface of the wafer 4 is not damaged. The induction member 6 can be set on the contact terminal 51. Of course, the receiving groove 52 can also only be set with a one-way side wall as an outwardly inclined structure to prevent the contact terminal 51 from contacting the front of the wafer 4. The inclined side walls of the receiving groove 52 ensure that the wafer 4 is smoothly introduced through the chamfered bevel during the clamping process, ensuring the stability of the wafer 4 clamping, and can be applied to the respective wafer clamping scenes.

[0039] In order to prevent the shoulder pole 5 and / or the induction member 6 and / or the contact terminal 51 from falling into the arc-shaped notch 2 and causing an adverse effect on the wafer 4 entering the arc-shaped notch 2 , the lifting arm 1 has a second mounting groove 11 for accommodating the contact terminal 51 .

[0040] The wafer lifting structure also includes a base 7, the lifting arm 1 is connected to the base 7, the base 7 is connected to a limiter 71, and the shoulder pole 5 is coaxially and movably connected to the limiter 71. Specifically, the limiter 71 and the shoulder pole 5 are parts of a cylinder, that is, the base 7 is connected to a cylinder structure, and the cylinder pushes the shoulder pole 5 to move telescopically. In this embodiment, the sensing member 6 is arranged on the limiter 71, which can sense the movable stroke of the shoulder pole 5 relative to the limiter 71.

[0041] For the setting of the second stroke, when no wafer 4 is hung on the opening end 3, the cylinder pushes the pole member 5 downward, and the sensor 6 detects the extreme state position of the pole member 5 pushed out by the cylinder to obtain the second stroke and initialize the position of the pole member 5 in the wafer-free state.

[0042] In order to provide installation space for the limiting member 71 and / or the sensing member 6 , the lifting arm 1 has a first installation groove 12 , and the limiting member 71 and / or the sensing member 6 is located in the first installation groove 12 .

[0043] The working process of the present invention is that when the sensing member 6 is arranged at the lower end of the shoulder pole member 5, when the wafer 4 is hung at the opening end 3 of the lifting arm 1, the wafer limit detection unit 9 moves downward along the through channel 8 until the shoulder pole member 5 with the contact end 51 abuts against the side wall of the wafer 4, at which time the sensing member 6 senses that the wafer 4 is effectively clamped in the arc-shaped notch 2. At this time, the shoulder pole member 5 and the opening end 3 cooperate to achieve a three-point stable clamping of the wafer 4, that is, the shoulder pole member 5 not only plays a role in sensing whether the wafer 4 is clamped, but also plays a role in clamping the wafer 4. When the wafer 4 needs to exit the arc-shaped notch 2, the shoulder pole member 5 moves upward to reset. Another situation is that when the wafer 4 is not accurately hung at the opening end 3, the contact end 51 does not come into contact with any object, the sensing member 6 cannot sense the object, and it is judged that the wafer 4 does not exist on the wafer lifting structure.

[0044] When the sensing element 6 is set on the limiting element 71, when the wafer 4 is hung at the opening end 3 between the lifting arms 1, the wafer limiting detection unit 9 moves downward by the first stroke, and the shoulder pole 5 with the contact end 51 (at this time, the sensing element may not be set) abuts against the side wall of the wafer 4. At this time, the sensing element 6 senses that the wafer 4 is effectively clamped in the arc-shaped notch 2. At this time, the shoulder pole 5 cooperates with the opening end 3 to achieve a three-point stable clamping of the wafer 4, that is, the shoulder pole 5 not only senses whether the wafer 4 is clamped, but also clamps the wafer 4; when the wafer 4 needs to exit the arc-shaped notch 2, the shoulder pole 5 moves upward to reset. In another case, when the wafer 4 is not accurately hung at the opening end 3, the shoulder pole 5 moves downward by the second stroke, and the second stroke is greater than the first stroke, indicating that the contact end 51 is not blocked by the wafer 4. At this time, the sensing element 6 senses that the wafer 4 is not effectively clamped in the arc-shaped notch 2.

[0045] The above specific implementation modes are used to explain the present invention rather than to limit the present invention. Any modification and change made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A wafer lifting structure, comprising at least one lifting arm (1), an arc-shaped notch portion (2) formed by the lifting arm (1), and an open end (3), wherein the inner diameter of the arc-shaped notch portion (2) is adapted to the outer diameter of a wafer (4), and the width of the open end (3) is smaller than the outer diameter of the wafer (4), characterized in that: It also includes a through channel (8) extending along the central axis of the arc-shaped notch (2), and a wafer limit detection unit (9), wherein the wafer limit detection unit (9) is movably arranged in the through channel (8), and at least a portion of it can pass through the lifting arm (1) along the second direction and extend into the arc-shaped notch (2) to abut against the wafer (4), and the through channel (8) has a limit pipe (81), and a portion of the wafer limit detection unit (9) is located in the limit pipe (81) to form a limit fit between the two in a first direction, and the first direction and the second direction are perpendicular or tend to be perpendicular.

2. The wafer lifting structure according to claim 1, characterized in that: The wafer limit detection unit (9) comprises a shoulder pole (5) movably arranged in the through channel (8), and a sensing component (6) connected to the shoulder pole (5); the shoulder pole (5) can pass through the lifting arm (1) and extend into the arc-shaped notch (2) to abut against the wafer (4); the sensing component (6) is used to sense whether the lifting arm (1) is clamping the wafer (4).

3. The wafer lifting structure according to claim 2, characterized in that: The sensing component (6) is arranged at the end of the shoulder pole component (5) and is used to sense whether the shoulder pole component (5) is in contact with the wafer (4).

4. The wafer lifting structure according to claim 2, characterized in that: The sensing member (6) is arranged on the side of the shoulder pole member (5) and is used to sense the relative movement distance of the shoulder pole member (5) relative to the lifting arm (1). The through channel (8) has an expanded diameter area (82) for accommodating the sensing member (6).

5. The wafer lifting structure according to claim 3, characterized in that: The end of the shoulder pole (5) is connected to a contact terminal (51), which has a receiving groove (52), and the opposite side walls of the receiving groove (52) are in the shape of a flared cone.

6. The wafer lifting structure according to claim 5, characterized in that: A second mounting groove (11) for accommodating a contact terminal (51) is provided between the lifting arms (1).

7. The wafer lifting structure according to claim 2, characterized in that: The moving path of the shoulder pole (5) coincides with or tends to coincide with the center line of the arc-shaped notch (2); the limiting pipe (81) and part of the wafer limiting detection unit (9) form a limiting match in a third direction, so that the shoulder pole (5) is located in the plane where the arc-shaped notch (2) is located.

8. The wafer lifting structure according to claim 7, characterized in that: The shoulder pole (5) has at least a first stroke and a second stroke. When the shoulder pole (5) moves in the first stroke, it abuts against the outer wall of the wafer (4) to cooperate with the lifting arm (1) to clamp the wafer (4). The second stroke is greater than the first stroke.

9. The wafer lifting structure according to claim 2, characterized in that: It also comprises a base (7), the lifting arm (1) being connected to the base (7); the base (7) being connected to a limiting member (71), and the shoulder pole member (5) being coaxially and movably connected to the limiting member (71).

10. The wafer lifting structure according to claim 9, characterized in that: The lifting arm (1) has a first installation slot (12), and the limiting member (71) is located in the first installation slot (12).

11. The wafer lifting structure according to claim 9, characterized in that: The shoulder pole member (5) and the limiting member (71) are parts of the cylinder.

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