Vacuum wafer lifting module and semiconductor process equipment

Abstract

The application belongs to the technical field of semiconductor equipment, and particularly relates to a vacuum wafer lifting module and a semiconductor process equipment, which comprises a lifting shaft and a substrate bearing unit mounted at the inner end of the lifting shaft, and further comprises a linear driving unit mounted outside a vacuum cavity and having a total length unchanged during movement, used for providing driving force; an independent linear guide unit used for providing high-precision linear motion guide for the lifting shaft; and an independent flexible dynamic sealing unit sleeved outside the lifting shaft and used for realizing dynamic sealing. The application realizes decoupling design of driving, guiding and sealing functions, and the functions are respectively borne by independent units, so that the application of the linear driving unit realizes compactness of the structure, the independent guiding unit guarantees movement precision, and the independent sealing unit has long service life due to ideal stress. The application realizes the beneficial effects of compact structure, accurate movement, reliable sealing and long service life.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor equipment technology, specifically a vacuum wafer lifting module and semiconductor process equipment. Background Technology

[0002] In the vacuum process environment of semiconductor manufacturing, such as in load locks, transfer chambers, or process chambers, precise and smooth vertical lifting and lowering of wafers is often required.

[0003] Existing wafer lifting technology solutions have many shortcomings. For example, the traditional rod-type cylinder or electric cylinder solution requires an additional space equal to the stroke length of the piston rod when it extends. This results in a large overall size of the equipment in the vertical direction, which is not conducive to the compact design of the equipment and also limits the layout of the equipment in space-constrained factories.

[0004] Another common approach uses a combination of a motor, ball screw, and flexible dynamic seals. In this approach, the drive motor and ball screw nut assembly are typically located within a vacuum chamber or connected to the chamber via a complex sealing structure. The transmission components located on the vacuum side require special vacuum lubrication, resulting in complex and costly maintenance. Furthermore, placing heat-generating components such as the motor within the vacuum chamber can lead to heat dissipation difficulties and potential particulate contamination, impacting the cleanliness of the process environment.

[0005] Furthermore, some solutions, in order to simplify the structure, directly utilize the rigidity of flexible dynamic seals (such as tubular seals with corrugated structures) to guide the lifting motion. However, the primary function of this seal is to achieve dynamic sealing, and its lateral stiffness is limited. When subjected to lateral forces or bending moments, this seal is highly susceptible to unexpected bending deformation, making it difficult to guarantee motion accuracy and stability. More seriously, this non-axial force can cause stress concentration in the seal, thereby drastically shortening its fatigue life, leading to seal failure, and increasing the risk of equipment downtime for maintenance.

[0006] Therefore, there is an urgent need for a vacuum wafer lifting solution that can simultaneously meet the requirements of compact structure, high motion accuracy, high sealing reliability, and long lifespan. Summary of the Invention

[0007] To address the problems mentioned in the background art, this invention provides a vacuum wafer lifting module and semiconductor process equipment. By decoupling the driving, guiding, and sealing functions and assigning them to independent units, the application of the linear driving unit achieves a compact structure, the independent guiding unit ensures motion accuracy, and the independent sealing unit achieves a long lifespan due to ideal force distribution. This invention achieves the beneficial effects of compact structure, precise motion, reliable sealing, and long lifespan.

[0008] This invention provides a vacuum wafer lifting module for lifting a substrate in a vacuum process environment. The vacuum wafer lifting module is configured to be mounted on a vacuum cavity and includes: a lifting shaft, which is vertically arranged, with a portion extending into the vacuum cavity through the wall panel and another portion extending out of the vacuum cavity; and a substrate carrying unit, which is mounted on the inner end of the lifting shaft located within the vacuum cavity; the vacuum wafer lifting module further includes: a linear drive unit, which is mounted on the outside of the vacuum cavity, and the total length of the linear drive unit remains constant during movement; the outer end of the lifting shaft located outside the vacuum cavity is connected to the moving part of the linear drive unit; an independent linear guide unit, which is mounted on the wall panel of the vacuum cavity or a component fixed to the wall panel, through which the lifting shaft passes and is provided with linear motion guidance; and an independent flexible dynamic sealing unit, which is sleeved on the outside of the lifting shaft, with one end hermetically connected to the wall panel of the vacuum cavity or a component fixed to the wall panel, and the other end hermetically connected to a follower component on the lifting shaft.

[0009] Furthermore, the linear drive unit is a rodless electric cylinder, and the moving part is the external slide of the rodless electric cylinder.

[0010] Furthermore, the linear guide unit is a linear bearing; the component fixed to the wall panel of the vacuum cavity is a flange, and one end of both the linear guide unit and the flexible dynamic sealing unit is connected to the flange.

[0011] Furthermore, the flexible dynamic sealing unit is a bellows.

[0012] Furthermore, the substrate carrier unit is a wafer carrier.

[0013] Furthermore, the linear guide unit includes at least two linear bearings spaced axially along the lifting shaft.

[0014] Furthermore, the lifting shaft has a hollow structure to form a vacuum channel, and the substrate support unit is provided with a vacuum suction hole that communicates with the vacuum channel.

[0015] Furthermore, it also includes a controller configured to control the linear drive unit to move in an S-shaped acceleration / deceleration curve.

[0016] Furthermore, the linear drive unit is a linear motor-driven air-float rodless electric cylinder, and the linear guide unit is an air-float bearing.

[0017] The present invention also provides a semiconductor process apparatus, including a vacuum chamber and any of the vacuum wafer lifting modules described above.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Compact structure, significantly saving vertical space. Since a linear drive unit with a constant total length during movement is used as the external drive source, there is no need to reserve extra space for the extension of the piston rod. The vertical height of the device can be reduced by more than 30% under the same stroke, which is conducive to the compactness and miniaturization of semiconductor devices.

[0019] (2) High precision and high stability. By setting up an independent linear guide unit specifically responsible for guidance, the guiding function and the sealing function are completely decoupled. The high-rigidity independent linear guide unit ensures the high-precision linear movement of the lifting shaft, avoiding the problems of unstable movement and decreased precision caused by lateral force on the seal in the traditional solution.

[0020] (3) Long life and high reliability. Since the independent flexible dynamic sealing unit only bears pure axial expansion and contraction and has no lateral bending stress, its fatigue life is greatly extended, reaching more than one million times, which significantly improves the reliability and durability of the entire module and reduces the risk of downtime due to seal failure.

[0021] (4) Vacuum environment friendly and easy to maintain. The main heat-generating and wear-prone components of the linear drive unit are located on the atmospheric side, avoiding thermal interference and particulate contamination in the vacuum chamber and ensuring the cleanliness of the process environment. At the same time, the core components such as drive, guide, and seal are modularly designed and can be replaced and maintained independently, reducing maintenance difficulty and cost. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present invention; Figure 2 This is a partially enlarged schematic diagram illustrating the decoupling of the guiding and sealing functions of this invention. Figure 3 This is a schematic diagram of the structure of a long-stroke embodiment of the present invention; Figure 4 This is a block diagram of the control system of the present invention; Figure 5 This is a schematic diagram of the S-shaped velocity curve of the lifting motion of the present invention; Explanation of reference numerals in the attached drawings: 10, vacuum chamber; 20, linear drive unit; 21, moving part; 22, motor; 23, encoder; 30, lifting shaft; 40, linear guide unit; 40a, first linear guide unit; 40b, second linear guide unit; 41, rolling element; 50, flexible dynamic sealing unit; 60, base plate bearing unit; 70, mounting flange; 80, auxiliary guide mechanism; 90, controller; 91, drive circuit. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0025] The following is in conjunction with the appendix Figure 1 To be continued Figure 5 The invention is described in detail with specific embodiments.

[0026] This invention provides a vacuum wafer lifting module, the core idea of ​​which lies in the complete decoupling of the three major functions of driving, guiding, and sealing. This allows each functional unit to operate independently under optimized conditions, thereby systematically improving the overall performance of the module. In the following description, to establish a consistent context, some key terms will be clarified. For example, the term "substrate" as used in the specification can refer to any sheet-like workpiece processed in semiconductor processes, including but not limited to semiconductor substrates, glass substrates, and photomasks.

[0027] In the technical solution of this invention, a "linear drive unit" refers to a drive device installed outside a vacuum chamber to provide linear driving force, whose total length remains constant during movement. This design significantly saves vertical installation space. Specifically, the linear drive unit can be implemented as a device that achieves external drive through internal magnetic force or mechanical belt coupling. The "moving part" refers to the portion of the linear drive unit that moves along its length to output motion.

[0028] Similarly, a "linear guide unit" refers to a component independent of the sealing function, specifically designed to provide high-precision linear motion guidance for the lifting shaft. The main responsibility of this unit is to withstand and counteract all radial forces and bending moments that may act on the lifting shaft, ensuring the accuracy of its motion trajectory. In specific implementations, this unit can be one or more guide components containing rolling elements, or high-precision guide elements such as guide components suspended by an air film. A "flexible dynamic sealing unit," on the other hand, is a component independent of the guiding function, achieving dynamic sealing of the vacuum cavity through its own elastic deformation. During operation, it only needs to withstand pure axial tension and compression, thus achieving an extremely long service life. A typical implementation of this unit is a metal or rubber tubular seal with a retractable corrugated structure.

[0029] The technical solution of the present invention will now be described in more detail with reference to the accompanying drawings. Figure 1 As shown, this invention provides a vacuum wafer lifting module for lifting substrates in a vacuum process environment. The module is typically mounted on the wall panel of a vacuum chamber 10, for example, at the bottom of the chamber. The module includes a vertically arranged lifting shaft 30, a portion of which passes through the wall panel of the vacuum chamber 10 and extends into the interior of the vacuum chamber 10, while the other portion extends to the exterior of the vacuum chamber 10, i.e., the atmospheric side. At the inner end of the lifting shaft 30 located within the vacuum chamber 10, a substrate support unit 60 is mounted for directly supporting and carrying the substrate.

[0030] The core feature of this invention is that the vacuum wafer lifting module further includes functionally decoupled drive, guide, and sealing units. Specifically, a linear drive unit 20 is installed outside the vacuum chamber 10, and its total length remains constant during movement. The end of the lifting shaft 30 located outside the vacuum chamber 10 is fixedly connected to the mover portion 21 of the linear drive unit 20 via a connector. Thus, the driving force is generated by the linear drive unit 20 located on the atmospheric side and transmitted to the lifting shaft 30 through the mover portion 21, realizing the externalization of the drive source and avoiding thermal impact and particulate contamination on the vacuum environment. Simultaneously, a linear guide unit 40 is installed on the wall panel of the vacuum chamber 10 or a component fixed to the wall panel (such as...). Figure 1 The lifting shaft 30 passes through the linear guide unit 40, as shown on the mounting flange 70. It provides precise linear motion guidance. Figure 2As shown in the enlarged view, the linear guide unit 40, through its internal rolling elements 41 and other structures, tightly constrains the radial position of the lifting shaft 30, thereby bearing all radial forces and bending moments that may arise during movement. Furthermore, a flexible dynamic sealing unit 50 is fitted around the outside of the lifting shaft 30. One end of this flexible dynamic sealing unit 50 is hermetically connected to the wall panel or mounting flange 70 of the vacuum chamber 10, and the other end is hermetically connected to a follower component (e.g., a ring welded to the shaft) on the lifting shaft 30. Figure 2 As shown, since the guiding function is fully undertaken by the linear guide unit 40, the flexible dynamic sealing unit 50 only undergoes pure axial stretching and compression when the lifting shaft 30 moves, completely avoiding lateral bending and torsional stress. This functional decoupling design greatly extends the fatigue life of the sealing unit and significantly improves the reliability of the entire module.

[0031] In a preferred embodiment, the linear drive unit 20 can be specifically a drive device whose total length remains constant during movement, with its mover portion 21 being the part of the drive device that moves along its length to output motion. Its "stroke-integrated" characteristic ensures that the overall length of the drive unit does not change with the stroke, and compared to traditional rod-type cylinders or electric cylinders, it can reduce the vertical height of the equipment by more than 30% while achieving the same lifting stroke, greatly promoting the compact design of semiconductor devices. Further, the linear guide unit 40 can be specifically a guide assembly including rolling elements 41. Meanwhile, for ease of installation and maintenance, the component fixed to the wall panel can be a mounting flange 70. Figure 1 and Figure 2 As shown, the mounting base for the linear guide unit 40 and the flexible dynamic sealing unit 50 can be integrated onto the mounting flange 70. Specifically, the guide assembly can be pressed into the center hole of the mounting flange 70, while one end of the flexible dynamic sealing unit 50 can be fixed to the mounting flange 70 by welding or flange connection. This integrated design simplifies the assembly process and ensures the coaxiality of the guide center and the sealing center.

[0032] In a long-stroke application scenario, to suppress the deflection and vibration of the lifting shaft 30 due to excessive cantilever length, the linear guide unit 40 may include at least two guide components spaced apart along the axial direction of the lifting shaft 30. For example... Figure 3As shown, the first linear guide unit 40a can be installed near the mounting flange 70 on the wall of the vacuum chamber 10, while the second linear guide unit 40b can be installed at a certain distance from the first linear guide unit 40a via an auxiliary guide mechanism 80. These two spaced-apart guide components form a stable dual-point support, which can effectively improve the rigidity and guiding accuracy of the lifting shaft 30, and ensure the smooth movement of the end of the substrate bearing unit 60 even with a long stroke of several hundred millimeters.

[0033] As a reliable and widely applicable implementation, the flexible dynamic sealing unit 50 can specifically be a metal tubular seal with a stretchable corrugated structure. This type of seal possesses excellent elasticity and vacuum sealing performance, capable of withstanding millions of expansion and contraction cycles. Since the seal no longer serves a guiding function in this invention, its lifespan and reliability are fundamentally improved compared to traditional designs. Correspondingly, the substrate support unit 60 can specifically be a bracket structure. The structure of this bracket can be designed according to the size and shape of the substrate it supports; for example, it can be a three-point structure for supporting a circular substrate, a ring support structure, or a tray with special positioning features. Its material is typically chosen for its low gas exudation rate, high temperature resistance, and lack of particulate contamination, such as PEEK (polyetheretherketone) or ceramics.

[0034] In certain specialized applications, such as when handling extremely thin or warped substrates, the module of this invention can integrate a vacuum adsorption function to prevent the substrate from sliding or vibrating during high-speed lifting and lowering. Specifically, the lifting shaft 30 can be designed as a hollow structure to form an internal vacuum channel. Simultaneously, a vacuum suction hole communicating with this vacuum channel is provided on the substrate support unit 60. Through external vacuum piping and solenoid valve control, the substrate can be vacuum-adsorbed when needed, thereby firmly fixing it to the substrate support unit 60, ensuring the stability and safety of the special substrate during the lifting and lowering process.

[0035] To achieve precise and smooth control of the lifting motion, the vacuum wafer lifting module of the present invention may further include a controller 90. For example... Figure 4 As shown, the controller 90 is configured to control the movement of the linear drive unit 20. Specifically, the controller 90 sends a motion command to the drive circuit 91, which in turn drives the motor 22 within the linear drive unit 20 to rotate. The encoder 23 on the motor 22 detects the position and speed of the motor 22 in real time and feeds the signals back to the drive circuit 91 and the controller 90, forming a closed-loop control system to achieve high-precision position control. In particular, the controller 90 can be configured to control the linear drive unit 20 to move along an S-shaped acceleration / deceleration curve. Figure 5As shown, compared to the traditional trapezoidal acceleration / deceleration curve, the S-shaped velocity curve exhibits a smooth, rather than abrupt, change in acceleration at the beginning and end of both acceleration and deceleration phases. This implies a smaller acceleration (impact). By employing S-shaped acceleration / deceleration control, the impact and vibration of the lifting shaft 30 during startup and shutdown can be significantly reduced, ensuring a smooth transition for the substrate it supports and preventing slippage or attitude changes caused by inertial forces. This is particularly important for high-precision processes.

[0036] To meet the needs of certain applications with extremely high production cycle requirements, this invention also provides a high-speed implementation solution. In this solution, the linear drive unit 20 can be a device that uses a linear motor for drive and utilizes air levitation technology to achieve contactless motion. Simultaneously, or optionally, the linear guide unit 40 can be a component that utilizes air film suspension to achieve contactless guidance. The linear motor directly generates driving force and has a fast response speed, while the air levitation technology allows the moving parts (i.e., the mover part 21 and the lifting shaft 30) to suspend above a compressed air film, with no physical contact between them and the fixed parts, thus achieving almost zero friction. This combination enables the lifting module to move at extremely high speeds and accelerations (e.g., up to 2g), significantly shortening the lifting cycle time.

[0037] Finally, the present invention also provides a semiconductor process apparatus comprising a vacuum chamber 10 and a vacuum wafer lifting module, as described above, mounted on the vacuum chamber 10. By integrating such a compact, precise, reliably sealed, and long-life lifting module, the overall performance, reliability, and compactness of the semiconductor process apparatus will be significantly improved.

[0038] To more clearly illustrate the technical solution of the present invention, a specific embodiment will be described below. Please refer to... Figure 1 and Figure 2This embodiment describes a basic vacuum wafer lifting module for lifting an 8-inch (200mm) substrate in a vacuum environment. The core design of this module strictly adheres to the principle of decoupling the driving, guiding, and sealing functions. In this embodiment, the linear drive unit 20 uses a commercially available magnetically coupled drive device with a rated stroke of 100mm. This drive device is vertically installed in the atmospheric environment outside the bottom of the vacuum chamber 10. Its working principle is that an internal servo motor drives a set of permanent magnets to move along the inside of the cylinder, and through magnetic force, non-contactly couples the movement of the external moving part 21 of the cylinder. This magnetic coupling transmission method naturally isolates the inside and outside, eliminating the need for penetrating dynamic seals, and is itself a clean transmission method. The module is connected to the vacuum chamber 10 via a mounting flange 70. This mounting flange 70 is made of 3mm thick 316L stainless steel sheet through laser cutting and machining, with a precision hole in the center, and is hermetically connected to the bottom plate of the vacuum chamber 10 by welding. Non-magnetic 316L stainless steel is chosen to avoid interference with the magnetic field of the magnetically coupled drive device. The lifting shaft 30 is machined from a 12mm diameter 304 stainless steel bar, and its surface undergoes precision grinding and polishing to reduce friction with the guide and sealing elements. The lifting shaft 30 is located at the end outside the vacuum chamber 10 and is securely connected to the mover portion 21 of the linear drive unit 20 via a custom-made connector. When the mover portion 21 moves up and down, the lifting shaft 30 also synchronously performs a precise vertical lifting motion.

[0039] The linear guide unit 40 employs a miniature rolling guide assembly with an inner diameter of 12 mm. This guide assembly is precisely pressed into a base mounted inside the mounting flange 70 (vacuum side). The lifting shaft 30 passes through this guide assembly 40, which provides stable and high-precision linear motion guidance. This design ensures that the radial runout of the lifting shaft 30 is strictly controlled within a minimal range throughout its 100 mm stroke. The flexible dynamic sealing unit 50 employs a welded corrugated tubular seal made of 304 stainless steel. This seal is fitted over the lifting shaft 30, with its lower end (fixed end) forming a vacuum-tight connection with the mounting flange 70 via welding, and its upper end (moving end) forming a vacuum-tight connection with a moving ring welded to the lifting shaft 30. In this way, the internal space of the vacuum chamber 10 is completely isolated by the seal, achieving a reliable dynamic vacuum seal. The substrate support unit 60, mounted on the top inner side of the lifting shaft 30, is specifically a three-point support structure made of PEEK material in this embodiment. PEEK material, with its low outgassing rate, high strength, and wear resistance, is ideal for use in ultra-high vacuum environments. Three support points are evenly distributed at 120-degree angles, stably supporting a 200mm diameter substrate. The operation of this embodiment is as follows: When the controller 90 issues a lifting command, the drive circuit 91 drives the motor 22 within the linear drive unit 20, and the mover part 21 subsequently drives the lifting shaft 30 to move vertically. During the lifting process, the lifting shaft 30 maintains a strictly vertical trajectory under the precise guidance of the linear guide unit 40, while the flexible dynamic sealing unit 50 synchronously stretches or compresses to maintain the seal of the vacuum chamber 10. By employing S-shaped acceleration and deceleration control, the entire lifting process is very smooth, avoiding any impact on the substrate. The technical effect achieved by this embodiment is very significant. Testing showed that the module achieves a repeatability accuracy of ±0.015mm within a 100mm stroke range. The entire module has a very compact structure, reducing the vertical space occupied by approximately 40% compared to solutions using traditional rod cylinders. Detection was performed using a helium mass spectrometer leak detector, and the overall leak rate was better than 1x10⁻⁶. -9 Pa·m 3 / s, meeting the requirements of high vacuum applications. Accelerated life testing of the flexible dynamic sealing unit 50 showed that after more than 1 million reciprocating cycles at full stroke, no fatigue damage or leakage occurred, demonstrating the significant improvement in reliability brought about by the functional decoupling design.

[0040] Based on the above basic embodiments, the present invention can also be modified according to different application requirements. For example, for applications requiring a longer lifting stroke, a long-stroke optimization scheme can be adopted. In an embodiment requiring a lifting stroke of 250mm, to ensure the rigidity and stability of the lifting shaft 30 in the long cantilever state, the diameter of the lifting shaft 30 is first increased from 12mm to 20mm to significantly improve its bending stiffness. The core optimization of this long-stroke scheme lies in the enhancement of the linear guide unit 40, which adopts a dual-guide structure. Specifically, a first linear guide unit 40a is installed at the mounting flange 70. In addition, an auxiliary guide mechanism 80 is added at the middle position of the lifting shaft 30, which contains a second linear guide unit 40b. These two guide units are spaced apart along the axial direction, jointly providing stable support for the lifting shaft 30 with a stroke of up to 250mm. This dual-point support structure can effectively suppress the vibration and deflection that may occur during the movement of the long shaft. Meanwhile, to accommodate longer strokes and larger substrates, the flexible dynamic sealing unit 50 utilizes a corrugated seal made of Inconel 718 alloy, which offers longer compression strokes and superior fatigue performance. The substrate support unit 60 has also been upgraded to a ring-shaped support structure suitable for 12-inch (300mm) substrates. Finite element analysis and actual measurements have verified that, under maximum overhang, the deflection at the end of the substrate support unit 60 in this long-stroke embodiment is less than 0.03mm, and the positioning error is controlled within ±0.03mm, fully meeting the requirements for stable and precise transport of large substrates within deep process cavities.

[0041] In another variant embodiment, to meet the demands of rapid pick-and-place cycles under high productivity requirements, this invention proposes a high-speed implementation scheme. The core of this scheme lies in replacing the corresponding components in the basic embodiment with low-friction, high-response components. Specifically, the linear drive unit 20 is replaced with a device that uses a linear motor drive and air flotation technology to achieve contactless motion. In this actuator, the driving force is directly generated by the linear motor without any mechanical transmission conversion, resulting in extremely fast response; simultaneously, its mover part 21 is suspended on the stator by an air flotation pad, achieving almost frictionless motion. Correspondingly, the linear guide unit 40 is also replaced with a component that utilizes air film suspension to achieve contactless guidance. The lifting shaft 30 is enveloped by high-pressure clean gas during movement, with no physical contact between it and the bearing sleeve, resulting in extremely low friction. This "dual air flotation" combination (air flotation drive + air flotation guide) enables the lifting shaft 30 to perform high-speed reciprocating motion with extremely low resistance. In an application requiring rapid lifting and lowering with a short stroke of 50mm, this solution achieved an acceleration of up to 2g and a maximum speed of 200mm / s, completing a single lifting and lowering motion within 0.5 seconds, significantly improving production cycle time and equipment efficiency. Of course, this solution requires an additional stable and clean compressed air source.

[0042] Furthermore, to address the need for processing special substrates, such as thin substrates less than 200μm thick or substrates with some warping, a vacuum adsorption function can be integrated into the basic embodiment. In this embodiment, the lifting shaft 30 is modified into a hollow structure, with its internal channels directly serving as vacuum pipelines. The top of the PEEK three-point support structure on the substrate carrier unit 60 is machined with tiny vacuum suction holes of 0.5mm in diameter, which converge through the internal channels of the lifting shaft 30. The external end of the lifting shaft 30 is connected to a vacuum pump via a vacuum rotary joint and a flexible hose, with a solenoid valve connected in series in the pipeline for on / off control. The workflow is as follows: when the substrate carrier unit 60 rises to the position to be picked up, the controller opens the solenoid valve, and the suction holes at the top of the bracket begin to generate negative pressure. When the robotic arm places the thin substrate on the bracket, the vacuum suction instantly and firmly adsorbs and fixes the substrate to the bracket. Throughout the high-speed lifting process, vacuum adsorption remains active, effectively preventing the substrate from sliding or vibrating due to inertial forces. Once the target position is reached, the solenoid valve is closed to release the vacuum, allowing the substrate to be released smoothly. This solution successfully addresses the instability issue of thin or warped substrates during lifting and lowering, significantly improving the success rate and safety of special processes.

[0043] The precise and smooth motion in all the above embodiments can be achieved by a single closed-loop control system. For example... Figure 4 The control system block diagram shown centered around a controller 90. The controller 90 plans the motion trajectory (e.g., an S-shaped speed curve) according to instructions from the upper-level software and sends commands to the drive circuit 91. The drive circuit 91 is responsible for providing power to the motor 22 within the linear drive unit 20 and continuously adjusting its output based on real-time position feedback signals from the encoder 23 at the tail of the motor 22 to ensure that the actual movement of the motor 22 strictly follows the commanded trajectory. Figure 5 The S-shaped velocity curve shown is key to achieving smooth motion. In the figure, the horizontal axis t represents time, and the vertical axis v represents velocity. A complete motion process includes an acceleration phase, a constant velocity phase, and a deceleration phase. Compared to traditional trapezoidal acceleration and deceleration, the S-shaped curve exhibits a continuous and gradual change in the rate of velocity change (i.e., acceleration) at the beginning and end of the acceleration phase, as well as at the beginning and end of the deceleration phase, avoiding abrupt changes in acceleration and thus keeping the impact at a very low level. This "soft start" and "soft stop" control strategy ensures that the substrate supported on the substrate carrier unit 60 experiences minimal inertial impact at the moment of start-up and stop, thereby avoiding slippage, vibration, or stress generation. This is crucial for ensuring the integrity and process precision of high-value substrates.

[0044] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the nature and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention.

Claims

1. A vacuum wafer lifting module for lifting a substrate in a vacuum process environment, the vacuum wafer lifting module being configured to be mounted on a vacuum chamber and comprising: The lifting shaft is vertically arranged, with one part extending into the vacuum cavity through the wall panel and the other part extending out of the vacuum cavity. And a substrate support unit, which is installed at the inner end of the lifting shaft located within the vacuum cavity; characterized in that the vacuum wafer lifting module further includes: A linear drive unit is installed outside the vacuum chamber, and the total length of the linear drive unit remains constant during movement; the lifting shaft is located at the outer end of the vacuum chamber and connected to the moving part of the linear drive unit; An independent linear guide unit is mounted on the wall panel of the vacuum chamber or on a component fixed to the wall panel, and the lifting shaft passes through the linear guide unit and is provided with linear motion guidance by it; It also includes an independent flexible dynamic sealing unit, which is sleeved on the outside of the lifting shaft. One end of the unit is airtightly connected to the wall panel of the vacuum cavity or a component fixed to the wall panel, and the other end is airtightly connected to the follower component on the lifting shaft.

2. The vacuum wafer lifting module according to claim 1, characterized in that, The linear drive unit is a rodless electric cylinder, and the moving part is the external slide of the rodless electric cylinder.

3. The vacuum wafer lifting module according to claim 1, characterized in that, The linear guide unit is a linear bearing; the component fixed to the wall panel of the vacuum cavity is a flange, and one end of both the linear guide unit and the flexible dynamic sealing unit is connected to the flange.

4. The vacuum wafer lifting module according to claim 1, characterized in that, The flexible dynamic sealing unit is a bellows.

5. The vacuum wafer lifting module according to claim 1, characterized in that, The substrate carrier unit is a wafer carrier.

6. The vacuum wafer lifting module according to claim 3, characterized in that, The linear guide unit includes at least two linear bearings spaced axially along the lifting shaft.

7. The vacuum wafer lifting module according to claim 1, characterized in that, The lifting shaft has a hollow structure to form a vacuum channel, and the substrate support unit is provided with a vacuum suction hole that communicates with the vacuum channel.

8. The vacuum wafer lifting module according to claim 1, characterized in that, It also includes a controller configured to control the linear drive unit to move in an S-shaped acceleration / deceleration curve.

9. The vacuum wafer lifting module according to claim 1, characterized in that, The linear drive unit is a linear motor-driven air-float rodless electric cylinder, and the linear guide unit is an air-float bearing.

10. A semiconductor process apparatus, characterized in that, include: Vacuum cavity and vacuum wafer lifting module as described in any one of claims 1-9.

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