Wafer transportation and anti-slippage system for a double-side exposure apparatus

Abstract

This invention discloses a wafer transport and anti-slip system for a double-sided exposure apparatus, relating to the field of wafer transport technology. It includes a base for supporting and installing the entire device, and further includes an adsorption mechanism for adsorbing and fixing the wafer, and a coordinating mechanism for gripping and transporting the wafer. The advantages of this system are: by integrating a vacuum adsorption mechanism, it achieves stable fixing of the wafer throughout the exposure process, effectively preventing pattern misalignment caused by slippage and vibration; by utilizing the coordinated design of a locking cylinder and an alignment stage, it achieves the separation operation of the robotic arm placement and mask alignment, significantly improving alignment accuracy and avoiding the influence of robotic arm errors; simultaneously, the smooth release of vacuum adsorption avoids the problem of the wafer being lifted during upper mask separation, significantly reducing the breakage rate and yield loss, and improving the reliability and efficiency of the double-sided exposure process.

Description

Technical Field

[0001] This invention relates to the field of wafer transport technology, and more specifically to a wafer transport and anti-slip system for a double-sided exposure apparatus. Background Technology

[0002] In existing technologies, double-sided exposure equipment typically employs the following process flow: A robotic arm picks up a wafer from an upstream station, transfers it, and places it on the surface of a fixed lower mask. At this point, the wafer maintains its position solely due to its own gravity. Subsequently, a drive mechanism lowers the upper mask vertically until it contacts and presses against the upper surface of the wafer. Once both masks are in contact with the wafer, the dual exposure light sources are activated simultaneously. Light passes through the patterns on their respective masks, projecting and exposing the patterns onto both sides of the wafer simultaneously. After the exposure process is complete, the upper mask is first lifted back to its initial height, and then the robotic arm removes the wafer from the surface of the lower mask and transfers it to a downstream station, thus completing the processing cycle for a single wafer.

[0003] However, this existing technical solution has several significant drawbacks. First, the lower mask is merely a mechanical support platform, lacking active adsorption and fixation capabilities; the wafer is positioned solely by gravity. This method is highly susceptible to variations in wafer thickness and surface flatness, causing slight changes in its actual position on the wafer stage, leading to misalignment of the exposure pattern. Conventional overlay errors can exceed 10 micrometers. Furthermore, minute vibrations during exposure can cause wafer slippage, resulting in the continuous accumulation of alignment deviations and severely impacting exposure accuracy. Second, during the separation process after exposure of the upper mask, the lack of a mechanism to eliminate vacuum pressure between the contact surfaces prevents the effective release of the adsorption force generated by the close contact between the mask and the wafer's upper surface. This leads to frequent instances of wafers being pulled up during upper mask lifting, with a pull rate as high as approximately 20%. Wafers accidentally pulled up may not only break upon subsequent drops but also significantly reduce production line yield, with yield losses reaching up to 15%. The aforementioned problems have become key technical bottlenecks restricting the accuracy and reliability of double-sided exposure processes. Summary of the Invention

[0004] The purpose of this invention is to provide a wafer transport and anti-slip system for a double-sided exposure apparatus, in order to solve the defects in the prior art that cause wafer slippage due to the lack of effective adsorption and fixation between the mask and the wafer, and cause the wafer to be carried out during the lifting of the upper mask.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a wafer transport and anti-slip system for a double-sided exposure apparatus, comprising a base for supporting and installing the overall device, and further comprising: an adsorption mechanism disposed on the top of the base for adsorbing and fixing the wafer, wherein the adsorption mechanism is fixedly disposed on a mask holder on the top of the base, and the base is fixedly disposed on a mask holder; and a cooperating mechanism disposed on the base for gripping and transporting the wafer, wherein the cooperating mechanism includes a robotic arm movably disposed on the base, and a cylinder for controlling the movement of the robotic arm is also fixedly disposed on the base.

[0006] Furthermore, the adsorption mechanism also includes several adsorption holes formed on the mask.

[0007] Furthermore, the adsorption mechanism also includes a vacuum-sealed glass inside the fixed mask holder.

[0008] Furthermore, a plurality of sealing blocks are fixedly disposed between the bottom of the vacuum-sealed glass and the top of the base; and a plurality of sealing rings are fixedly disposed between the mask frame and the vacuum-sealed glass.

[0009] Furthermore, the collaborative mechanism also includes an alignment worktable movably disposed on the top of the base, and a rotating block is movably disposed on the top of the base at the side of the alignment worktable.

[0010] Furthermore, the collaborative mechanism also includes a switch movably mounted on the base, and a suction cup movably mounted on the end of the robotic arm.

[0011] Furthermore, a locking cylinder is fixedly installed on the side wall of the robotic arm.

[0012] Compared with existing technologies, the present invention provides a wafer transport and anti-slip system for a double-sided exposure apparatus. A robotic arm, driven by a cylinder, uses a suction cup at its end to pick up a wafer from the loading position and transfer it to the surface of a photomask. Subsequently, a locking cylinder on the side wall of the robotic arm extends, temporarily locking the wafer onto the photomask. Then, the suction cup releases and lifts, allowing the alignment stage to precisely align the photomask holder and the photomask on it with the wafer in the XY plane. Fine-tuning in the Y direction is performed using a rotating block. After alignment, the locking cylinder retracts, and the adsorption mechanism activates. A vacuum negative pressure is formed through the adsorption holes on the photomask and the sealed cavity composed of the vacuum-sealed glass, sealing block, and sealing ring below, uniformly adsorbing and fixing the wafer. Double-sided exposure is then performed. After exposure, the vacuum is released, and the robotic arm removes the wafer again. The advantages of this system are as follows: By integrating a vacuum adsorption mechanism, it achieves stable fixation of the wafer throughout the exposure process, effectively preventing pattern misalignment caused by slippage and vibration; by utilizing the coordinated design of the locking cylinder and the alignment stage, it realizes the separation operation of the robot arm placement and mask alignment, which greatly improves the alignment accuracy and avoids the influence of robot arm errors; at the same time, the smooth release of vacuum adsorption avoids the problem of the wafer being carried away when separating the upper mask, which significantly reduces the breakage rate and yield loss, and improves the reliability and efficiency of the double-sided exposure process. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0014] Figure 1 This is a side view schematic diagram of the mask structure provided in an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of the overall structure of the wafer transport and anti-slip system provided in an embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures:

[0017] 1. Mask holder; 2. Mask; 3. Vacuum-sealed glass; 4. Sealing block; 5. Sealing ring; 6. Alignment table; 7. Rotating block; 8. Base; 9. Locking cylinder; 10. Robot arm; 11. Switch; 12. Cylinder; 13. Suction cup. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0019] As attached Figure 1To be continued Figure 2 As shown:

[0020] Example 1:

[0021] This invention provides a wafer transport and anti-slip system for a double-sided exposure apparatus, including a base 8 for supporting and installing the entire device, and further including: an adsorption mechanism disposed on the top of the base 8 for adsorbing and fixing the wafer, the adsorption mechanism being fixedly disposed on a mask holder 1 on the top of the base 8, and a mask 2 being fixedly disposed on the base 8 through the mask holder 1; and a cooperating mechanism disposed on the base 8 for gripping and transporting the wafer, the cooperating mechanism including a robotic arm 10 movably disposed on the base 8, and a cylinder 12 fixedly disposed on the base 8 for controlling the movement of the robotic arm 10;

[0022] Simultaneously, a robotic arm 10, driven by a cylinder 12, uses a suction cup 13 at its end to pick up a wafer from the loading position and transfer it to the surface of the mask 2. Subsequently, a locking cylinder 9 on the side wall of the robotic arm 10 extends, temporarily locking the wafer onto the mask 2. Then, the suction cup 13 is released and lifted, allowing the alignment table 6 to drive the mask holder 1 and the mask 2 on it to precisely align with the wafer in the XY plane. Fine adjustments in the Y direction are made by a rotating block 7. After alignment, the locking cylinder 9 retracts, and the adsorption mechanism is activated. A vacuum negative pressure is formed through the adsorption holes on the mask 2 and the sealed cavity formed by the vacuum-sealed glass 3, the sealing pressure block 4, and the sealing ring 5 below, uniformly adsorbing and fixing the wafer. After double-sided exposure, the vacuum is released after exposure, and the robotic arm 10 removes the wafer again. The advantages of this system are as follows: By integrating a vacuum adsorption mechanism, the wafer is stably fixed throughout the exposure process, effectively preventing pattern misalignment caused by slippage and vibration; by utilizing the coordinated design of the locking cylinder 9 and the alignment stage 6, the separation operation of the robot arm 10 for placement and alignment with the mask 2 is realized, which greatly improves the alignment accuracy and avoids the influence of robot arm 10 errors; at the same time, the smooth release of vacuum adsorption avoids the problem of the wafer being lifted when separating from the upper mask 2, which significantly reduces the breakage rate and yield loss, and improves the reliability and efficiency of the double-sided exposure process.

[0023] refer to Figure 1 and Figure 2 The adsorption mechanism includes a base 8, a mask holder 1, a mask 2, a vacuum-sealed glass 3, a sealing block 4, and a sealing ring 5;

[0024] An adsorption mechanism is constructed on the base 8, with its core component, the mask holder 1, directly fixed to the base 8 as an installation platform. This allows for precise mounting of the mask 2 and initial adsorption and fixation via its built-in vacuum circuit. The mask 2 has an array of adsorption holes on its surface, crucial for its functionality. Below it, the vacuum-sealed glass 3 is pressed and fixed to the base 8 platform by a sealing block 4, forming the bottom of the cavity. A sealing ring 5 is embedded at the interface between the mask holder 1 and the vacuum-sealed glass 3 to ensure a vacuum seal. Once the wafer is placed covering the adsorption holes of the mask 2, all components together form a sealed cavity. A vacuum is drawn through the evacuation holes on the mask holder 1, and atmospheric pressure is applied evenly to the wafer through the adsorption holes of the mask 2, achieving stress-free, full-area adsorption and fixation. The advantages of this mechanism are: through the integrated, multi-stage sealed vacuum chamber design, it provides an extremely stable and uniform adsorption force, eliminating any slippage or micro-movement of the wafer during the exposure process, laying a solid positioning foundation for ultra-high precision lithography, and avoiding the risk of damage or contamination caused by contact clamping.

[0025] Example 2:

[0026] Referring to the figure, the collaborative mechanism includes a base 8, an alignment worktable 6, a rotating block 7, a robotic arm 10, a locking cylinder 9, a switch 11, a cylinder 12, and a suction cup 13;

[0027] By setting up a collaborative mechanism, also supported by the base 8, the core robotic arm 10 is hinged and mounted via cylinder 12, enabling the wafer to be swung and transported between the loading position and the working position. The suction cup 13 at the end of the robotic arm 10 is controlled by switch 11 to lift and lift, and is responsible for directly gripping the wafer. To ensure precise alignment between the wafer and the mask 2, the system is equipped with a precision adjustment unit: the alignment stage 6 is mounted on the base 8 and supports the mask frame 1, and can be driven to move in the XY plane; the rotating block 7 on its side is specifically used to control fine adjustment in the Y direction. The key transition locking function in the process is achieved by the locking cylinder 9, which is mounted on the side wall of the robotic arm 10. When the robotic arm 10 places the wafer on the mask 2, the locking cylinder 9 extends to temporarily lock and fix the wafer. Then the suction cup 13 of the robotic arm 10 is released and lifted. At this time, the alignment stage 6 can drive the mask 2 and the locked wafer to perform alignment and adjustment. After completion, the locking cylinder 9 retracts, and the adsorption mechanism starts vacuum to complete the final fixation. The advantages of this mechanism are: it achieves fully automated and highly flexible wafer handling and precise alignment. Through the separate process design of "placement of robot arm 10 - temporary fixation of locking cylinder 9 - alignment of dedicated worktable", it eliminates the influence of the motion chain error of robot arm 10 on the final alignment accuracy. The intervention of locking cylinder 9 ensures the stability and undisturbed alignment process. The overall system is efficient, reliable and has extremely high alignment accuracy.

[0028] Working principle: First, the robotic arm 10 in the collaborative mechanism moves to the loading position under the drive of the cylinder 12. The suction cup 13 at its end picks up the wafer to be processed and smoothly transfers it to the surface of the mask 2 located on the mask holder 1. Then, the locking cylinder 9 on the side wall of the robotic arm 10 extends to temporarily press and lock the wafer onto the mask 2. After that, the suction cup 13 releases the vacuum and lifts, separating the robotic arm 10 from the wafer. Next, the alignment stage 6 of the collaborative mechanism starts to work, driving the mask holder 1 and mask 2 it carries, along with the wafer temporarily fixed by the locking cylinder 9, to perform precise position adjustment in the XY plane. The rotating block 7 is specifically used for fine adjustment in the Y direction, thereby completing the precise alignment of the wafer and the pattern of the mask 2. This design realizes the separation of the robotic arm 10 placement operation and the mask 2 alignment operation, avoiding the need for the robotic arm 10 to... The inherent error affects the final accuracy; after alignment, the locking cylinder 9 retracts to release the temporary fixation, and at the same time, the adsorption mechanism is immediately activated. Through the array of adsorption holes opened on the mask 2, it connects with the sealed cavity formed by the vacuum-sealed glass 3, the sealing block 4, and the sealing ring 5 inside the mask frame 1. A vacuum is drawn to form a uniform and stable negative pressure, which adsorbs and fixes the entire wafer to the surface of the mask 2, thereby completely preventing slippage and vibration during the exposure process; then, the equipment performs a double-sided exposure process; after the exposure process is completed, the adsorption mechanism first smoothly releases the vacuum state, eliminating the adsorption force between the mask 2 and the wafer, effectively avoiding the problem of the wafer being lifted when the upper mask 2 is raised; finally, the robot arm 10 descends again and picks up the exposed wafer through the suction cup 13, transferring it to the downstream station, thus completing a complete work cycle.

[0029] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A wafer transport and anti-slip system for a double-sided exposure apparatus, comprising a base (8) for supporting and installing the entire apparatus, characterized in that, Also includes: An adsorption mechanism is set on the top of the base (8) for adsorbing and fixing the wafer. The adsorption mechanism is fixedly set on the mask frame (1) on the top of the base (8). The base (8) is fixedly set with a mask (2) through the mask frame (1). A collaborative mechanism is set on the base (8) for gripping and transporting wafers. The collaborative mechanism includes a robotic arm (10) movably set on the base (8). A cylinder (12) for controlling the movement of the robotic arm (10) is also fixedly set on the base (8).

2. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 1, characterized in that, The adsorption mechanism also includes several adsorption holes formed on the mask plate (2).

3. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 2, characterized in that, The adsorption mechanism also includes a vacuum-sealed glass (3) inside the fixed mask frame (1).

4. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 3, characterized in that, Several sealing blocks (4) are fixedly arranged between the bottom of the vacuum-sealed glass (3) and the top of the base (8). Furthermore, several sealing rings (5) are fixedly arranged between the mask plate frame (1) and the vacuum-sealed glass (3).

5. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 1, characterized in that, The collaborative mechanism also includes an alignment worktable (6) movably disposed on the top of the base (8), and a rotating block (7) is movably disposed on the top of the base (8) at the side of the alignment worktable (6).

6. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 5, characterized in that, The collaborative mechanism also includes a switch (11) movably mounted on the base (8), and a suction cup (13) movably mounted on the end of the robotic arm (10).

7. The wafer transport and anti-slip system of a double-sided exposure apparatus according to claim 6, characterized in that, A locking cylinder (9) is fixedly installed on the side wall of the robotic arm (10).

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