A test platform of wafer lifting structure

Abstract

The utility model discloses a kind of test platform of wafer lifting structure, including the test cavity capable of simulating vacuum environment, position detection unit, single lifting unit, lifting rotation unit and control unit, position detection unit is set in test cavity, single lifting unit is installed at the bottom of test cavity for driving wafer to move up and down, lifting rotation unit is installed at the bottom of test cavity for driving wafer rotation, while moving up and down, control unit is connected with position detection unit, for calculating wafer repeat positioning accuracy and stability according to detection data;Single lifting unit and lifting rotation unit can be switched installation.The test platform of wafer lifting structure provided by the utility model can be in simulated real working condition, reliability, position offset and performance attenuation of each component of lifting mechanism are comprehensively and quantitatively evaluated, which provides basis for improving design and predicting maintenance cycle, and ultimately helps to solve the problem of uneven film and yield decline caused by lifting mechanism problem.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor technology, and in particular to a test platform for a wafer lifting structure. Background Technology

[0002] With the refinement of semiconductor manufacturing processes, the uniformity of thin films on the wafer surface has an increasingly significant impact on device performance. Thin film uniformity depends on environmental parameters such as airflow distribution, temperature field, and plasma field within the reaction chamber, while the reliability of the wafer lifting mechanism directly determines the positioning accuracy and stability of the wafer during the transfer process. If the lifting mechanism experiences positional deviations, jamming, or sealing failures during long-term operation, it will lead to uneven film thickness / composition on the wafer surface, thereby causing a decrease in device yield.

[0003] In existing technologies, wafer lifting mechanisms need to operate in a vacuum environment for extended periods. The reliability, repeatability, and lifespan of their components (such as linear guides, seals, and servo systems) directly affect the wafer's positional stability. However, there is currently a lack of dedicated testing platforms that can simultaneously simulate a vacuum environment and integrate both lifting and rotation modes. This makes it impossible to fully assess the performance degradation, positional deviation, and component failures of the lifting mechanism under real-world operating conditions, thereby impacting the yield and maintenance costs of semiconductor equipment. Utility Model Content

[0004] The embodiments of this utility model provide a test platform for wafer lifting structure, which solves the technical problem that traditional test platforms cannot simultaneously simulate a vacuum environment and integrate lifting / rotation dual-mode testing, resulting in incomplete testing and thus affecting the yield and maintenance cost of semiconductor equipment.

[0005] To address the aforementioned problems, according to one aspect of this application, an embodiment of the present invention provides a test platform for a wafer lifting structure. The test platform includes a test chamber capable of simulating a vacuum environment, a position detection unit, a single lifting unit, a lifting-rotation unit, and a control unit. The position detection unit is disposed within the test chamber for real-time detection of the wafer's displacement and tilt. The single lifting unit is installed at the bottom of the test chamber for driving the wafer to move up and down. The lifting-rotation unit is installed at the bottom of the test chamber for driving the wafer to rotate and move up and down simultaneously. The control unit is connected to the position detection unit and is used to calculate the wafer's repeatability and stability based on the detection data. The single lifting unit and the lifting-rotation unit can be switched between each other.

[0006] In some embodiments, the test chamber has a vacuum pump connection port and a backfill gas connection port. The test chamber is connected to an external vacuum pump through the vacuum pump connection port and to a process gas backfill pipeline through the backfill gas connection port. The test chamber has a vacuum gauge installed on the inner wall of the test chamber for real-time monitoring of the chamber pressure and transmitting data to the control unit.

[0007] In some embodiments, the single lifting unit includes a first motor, a linear slide rail, a first coupling, a lifting bracket, and a first limiting module. The output end of the first motor is connected to the linear slide rail through the first coupling. The lifting bracket is fixed on the slider of the linear slide rail to carry the test wafer. The first limiting module is disposed at the end point of the stroke of the linear slide rail.

[0008] In some embodiments, the lifting and rotating unit includes a lifting drive module, which includes a second motor, a first reducer, a second coupling, a lifting slide rail, and a wafer carrier. The output end of the second motor is coaxially connected to the input end of the first reducer through the second coupling. The output end of the first reducer is connected to the lifting slide rail. The wafer carrier is fixed on the slider of the lifting slide rail and moves vertically up and down along the lifting slide rail. The upper and lower stroke endpoints of the lifting slide rail are respectively provided with second limit modules.

[0009] In some embodiments, the lifting and rotating unit further includes a rotation drive module, which includes a third motor, a second reducer, and a third coupling. The output end of the third motor is coaxially connected to the input end of the second reducer through the third coupling. The output end of the second reducer is fixed to the wafer carrier, and the wafer carrier is connected to the top of the slider of the lifting slide rail.

[0010] In some embodiments, the rotary drive module further includes a bellows and a rotary seal, the bellows sealingly covering the lifting slide rail, and the rotary seal being disposed at the rotation axis of the wafer carrier.

[0011] In some embodiments, the position detection unit includes at least two laser ranging modules disposed above the wafer. Each laser ranging module includes a laser emitter, a laser receiver, and a processor. The laser emitter emits a detectable laser onto the wafer, the laser receiver receives diffusely reflected laser light from the wafer surface, and the processor calculates the real-time position and tilt of the wafer based on the laser reflection time difference. The processor is configured to: determine that the wafer has shifted position when the position difference between two detection points is greater than 0.1 mm; and determine that the repeatability accuracy is unqualified when the position deviation before and after lifting is greater than ±0.1 mm.

[0012] In some embodiments, the control unit is configured to: perform more than one million cycle tests on the single lifting unit or the lifting and rotating unit; record position data after each lifting and lowering, and calculate the repeatability accuracy.

[0013] In some embodiments, the single lifting unit and the lifting and rotating unit can be interchangeably installed at the bottom of the test chamber via a quick-release structure.

[0014] In some embodiments, the first limit module is a limit switch or a photoelectric sensor.

[0015] Compared with the prior art, the test platform of the wafer lifting structure of this utility model has at least the following beneficial effects:

[0016] The wafer lifting structure test platform provided by this utility model includes a test chamber capable of simulating a vacuum environment, a position detection unit, a single lifting unit, a lifting and rotating unit, and a control unit. The position detection unit is disposed in the test chamber for real-time detection of the wafer's displacement and tilt. The single lifting unit is installed at the bottom of the test chamber for driving the wafer to move up and down. The lifting and rotating unit is installed at the bottom of the test chamber for driving the wafer to rotate and move up and down simultaneously. The control unit is connected to the position detection unit and is used to calculate the wafer's repeatability and stability based on the detection data. The single lifting unit and the lifting and rotating unit can be switched between installations.

[0017] This invention simulates a real vacuum working environment through a test chamber, solving the problem of lacking vacuum environment simulation in previous studies. The position detection unit directly and in real-time detects wafer displacement and tilt in a vacuum environment, providing a direct means to quantify performance degradation and positional deviation. The switchable installation design of the single lifting unit and the lifting-rotation unit allows the platform to test the performance of two key motion modes—pure lifting and lifting plus rotation—under vacuum, either separately or in combination, solving the problem of lacking integrated dual-mode testing capabilities in previous studies. The control unit uses the data from the position detection unit to accurately calculate the repeatability and stability indicators that are crucial for long-term operation. Therefore, the entire testing platform can comprehensively and quantitatively evaluate the reliability, positional deviation, and performance degradation of each component of the lifting mechanism under simulated real working conditions, providing a basis for design improvement and predicting maintenance cycles, ultimately helping to solve the problems of film inhomogeneity and yield reduction caused by lifting mechanism issues.

[0018] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This invention presents a schematic diagram of the structure of a test platform for a wafer lifting structure according to an embodiment of the present invention.

[0021] Figure 2 This invention presents a front view of a test platform for a wafer lifting structure according to an embodiment of the present invention.

[0022] Figure 3 This invention illustrates a schematic diagram of a single lifting unit in a test platform for a wafer lifting structure provided by an embodiment of the present invention.

[0023] Figure 4 This invention illustrates a schematic diagram of the rotating lifting unit in a test platform for a wafer lifting structure provided by an embodiment of the present invention.

[0024] Figure 5 A partial cross-sectional view of a test platform for a wafer lifting structure provided in an embodiment of this utility model is shown;

[0025] Figure 6 This invention illustrates a schematic diagram of the position detection unit in a test platform for a wafer lifting structure provided in an embodiment of the present invention.

[0026] Figure 7 A schematic diagram of a test platform for a wafer lifting structure provided by an embodiment of this utility model is shown.

[0027] Figure label:

[0028] 1. Test chamber; 11. Vacuum pump connection port; 12. Backfill gas connection port; 13. Vacuum gauge; 2. Position detection unit; 21. Laser emitter; 22. Laser receiver; 23. Processor; 3. Single lifting unit; 4. Lifting and rotating unit; 5. Control unit; 31. First motor; 32. Linear slide rail; 33. First coupling; 34. Lifting bracket; 35. First limit module; 41. Lifting drive module; 42. Rotation drive module; 411. Second motor; 412. First reducer; 413. Second coupling; 414. Lifting slide rail; 415. Wafer bracket; 416. Second limit module; 417. Support component; 421. Third motor; 422. Second reducer; 423. Third coupling; 424. Bellows; 425. Rotary seal; 6. Frame; 7. Wafer. Detailed Implementation

[0029] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the specific implementation methods, structures, features, and effects according to this utility model application are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0030] In the description of this utility model, it should be clarified that the terms "first," "second," etc., in the specification, claims, and drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence; the terms "vertical," "lateral," "longitudinal," "front," "back," "left," "right," "up," "down," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model, and do not mean that the device or element referred to must have a specific orientation or position, and therefore should not be construed as a limitation of this utility model.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0033] This embodiment provides a test platform for wafer lifting structures, such as Figures 1-7 As shown, the test platform includes a test chamber 1 capable of simulating a vacuum environment, a position detection unit 2, a single lifting unit 3, a lifting and rotating unit 4, and a control unit 5. The position detection unit 2 is disposed within the test chamber 1 for real-time detection of the wafer's displacement and tilt. The single lifting unit 3 is installed at the bottom of the test chamber 1 for driving the wafer to move up and down. The lifting and rotating unit 4 is installed at the bottom of the test chamber 1 for driving the wafer to rotate and move up and down simultaneously. The control unit 5 is connected to the position detection unit 2 and is used to calculate the wafer's repeatability and stability based on the detection data. The single lifting unit 3 and the lifting and rotating unit 4 can be switched between each other. The test platform also includes a frame 6, which supports the test chamber 1.

[0034] Test chamber 1 is the basic structure of the entire test, providing a vacuum environment inside. Position detection unit 2 is directly installed inside the test chamber 1 at the top or a specific position, allowing its sensing surface to directly observe the wafer inside the chamber. Single lifting unit 3 and lifting and rotating unit 4 are both installed at the bottom of test chamber 1, with their motion execution components extending upward into the chamber to support and drive the wafer 7. These two units are designed to be interchangeable and installed at the same position at the bottom of the chamber. Control unit 5 is usually located outside test chamber 1 and is electrically connected to position detection unit 2, single lifting unit 3, and lifting and rotating unit 4 via cables or interfaces, respectively, to send control commands and receive test data.

[0035] The primary function of test chamber 1 is to provide a vacuum-sealed space that can be evacuated, simulating the vacuum environment of the actual operation of the wafer lifting mechanism. Position detection unit 2 measures the position and tilt angle of the wafer within test chamber 1 in real-time and with high precision during its movement. Single lifting unit 3 drives the wafer to perform purely vertical lifting motion within test chamber 1. Lifting-rotation unit 4 drives the wafer to simultaneously perform rotational and vertical lifting motions, or a combination of both, within test chamber 1. Control unit 5 coordinates the entire testing process; it controls single lifting unit 3 or lifting-rotation unit 4 to execute the specified motion mode, receives and processes detection data from position detection unit 2, and ultimately calculates and outputs key performance indicators such as repeatability and motion smoothness of wafer 7.

[0036] In the specific working process, a vacuum environment is first established within the test chamber 1. Depending on the testing requirements, either a single lifting unit 3 or a lifting-rotating unit 4 is installed at the bottom of the chamber. The control unit 5 sends motion commands to the selected unit (single lifting unit 3 or lifting-rotating unit 4), driving the wafer 7 it carries to move within the vacuum chamber according to a set pattern. During this process, the position detection unit 2 continuously monitors the real-time position and tilt of the wafer 7 and transmits this data to the control unit 5 in real time. The control unit 5 receives and processes this data, calculating the repeatability accuracy by analyzing the consistency of the wafer 7 reaching the target position in multiple motion cycles, and evaluating the smoothness of the motion by analyzing changes in position and tilt during the movement.

[0037] This embodiment simulates a real vacuum working environment through test chamber 1, solving the problem of lacking vacuum environment simulation in the previous embodiment. Position detection unit 2 directly and in real-time detects the displacement and tilt of wafer 7 under vacuum conditions, providing a direct means to quantify performance degradation and positional deviation. The switchable installation design of the single lifting unit 3 and the lifting-rotation unit 4 allows the platform to test the performance of the two key motion modes of wafer 7—pure lifting and lifting plus rotation—under vacuum, either separately or in combination, solving the problem of lacking integrated dual-mode testing capabilities in the previous embodiment. Control unit 5 uses the data from position detection unit 2 to accurately calculate the repeatability and stability indicators, which are crucial for long-term operation. Therefore, the entire testing platform can comprehensively and quantitatively evaluate the reliability, positional deviation, and performance degradation of each component of the lifting mechanism under simulated real working conditions, providing a basis for design improvement and predicting maintenance cycles, ultimately helping to solve the problems of film inhomogeneity and yield reduction caused by lifting mechanism issues.

[0038] In a specific embodiment, the test chamber 1 has a vacuum pump connection port 11 and a backfill gas connection port 12. The test chamber 1 is connected to an external vacuum pump through the vacuum pump connection port 11, and the test chamber 1 is connected to a process gas backfill pipeline through the backfill gas connection port 12. The test chamber 1 has a vacuum gauge 13 installed on the inner wall of the test chamber 1 for real-time monitoring of the chamber pressure and transmitting data to the control unit 5.

[0039] Both the vacuum pump connection port 11 and the backfill gas connection port 12 are located on the shell of the test chamber 1, typically on the side wall or top of the chamber, serving as interfaces for gas entry and exit. The vacuum pump connection port 11 is connected to an external vacuum pump system via a pipe. The backfill gas connection port 12 is connected to a process gas backfill pipeline via a pipe. The vacuum gauge 13 is directly mounted on the inner wall of the test chamber 1, with its sensor portion exposed inside the chamber. It directly senses the internal pressure and is electrically connected to the control unit 5 via a cable or interface to transmit pressure data. The vacuum pump connection port 11 provides an interface for connecting the test chamber 1 to an external vacuum pump, allowing the external vacuum pump to extract air from the test chamber 1 to achieve and maintain the required vacuum level. The backfill gas connection port 12 provides an interface for connecting the test chamber 1 to an external process gas pipeline, allowing the precise introduction of specific types and flow rates of process gas into the chamber under vacuum conditions or after reaching a specific vacuum level, to simulate the actual gas environment in semiconductor manufacturing equipment. The function of vacuum gauge 13 is to measure the vacuum pressure inside test chamber 1 in real time and directly, and transmit the precise pressure data to control unit 5 for monitoring and feedback control of the vacuum status of the chamber.

[0040] The vacuum pump connection 11, backfill gas connection 12, and vacuum gauge 13 work together to achieve precise control of the internal environment of the test chamber 1. First, an external vacuum pump evacuates the test chamber 1 through the vacuum pump connection 11, while the vacuum gauge 13 monitors the internal pressure in real time and transmits the data to the control unit 5. When the pressure reaches the target vacuum level, the control unit 5 can instruct the pumping to stop or maintain the vacuum pump operation to stabilize the pressure. Next, according to the test requirements, the control unit 5 can instruct the injection of specific process gases into the vacuum chamber through the backfill gas connection 12, while the vacuum gauge 13 continuously monitors pressure changes to ensure that the pressure after gas introduction remains stable at the set value. This combined operation enables the dynamic and precise establishment and maintenance of various required vacuum environments within the test chamber 1, flexibly simulating the actual process gas atmosphere in semiconductor equipment. This provides a more realistic environmental condition for wafer lifting mechanism testing, significantly improving the authenticity and reliability of the test results.

[0041] In a specific embodiment, the single lifting unit 3 includes a first motor 31, a linear slide rail 32, a first coupling 33, a lifting bracket 34, and a first limiting module 35. The output end of the first motor 31 is connected to the linear slide rail 32 through the first coupling 33. The lifting bracket 34 is fixed on the slider of the linear slide rail 32 to support the test wafer 7. The first limiting module 35 is disposed at the end point of the stroke of the linear slide rail 32.

[0042] The first motor 31 is a servo motor, installed outside or at the bottom of the test chamber 1. Its output shaft is directly connected to the drive shaft of the linear slide rail 32 via the first coupling 33. The main body of the linear slide rail 32 is fixed to the bottom of the test chamber 1, and its slider can make precise linear movements on the slide rail. The lifting bracket 34 is installed on the slider and moves up and down with the slider. Its top is located inside the test chamber 1 to support the wafer 7. The first limit module 35 is installed on the base of the linear slide rail 32 and is precisely set near the highest and lowest points of the slide rail's travel to detect or limit the extreme positions of the slider. The function of the first motor 31 is to provide power to drive the movement of the lifting mechanism. The function of the linear slide rail 32 is to convert the rotational motion of the first motor 31 into precise and smooth linear lifting motion, and to provide guidance and support for the lifting bracket 34. The function of the first coupling 33 is to connect the output shaft of the first motor 31 and the drive shaft of the linear slide rail 32, transmit torque, and allow for a certain degree of installation deviation compensation. The function of the lifting bracket 34 is to directly support and fix the wafer 7 to be tested, serving as a platform for the wafer's lifting and lowering movement. The function of the first limit module 35 is to define the physical upper and lower limit positions of the lifting bracket 34's movement, preventing the slider from exceeding its safe travel range and causing equipment damage, while also providing position signals.

[0043] Upon receiving a command from the control unit 5, the first motor 31 begins to rotate, and its torque is transmitted to the drive shaft of the linear guide rail 32 via the first coupling 33. The rotational motion of the drive shaft is converted by the linear guide rail 32 into precise vertical linear motion of the slider on it. The lifting bracket 34, fixed on the slider, moves up and down synchronously, thereby driving the wafer 7 it carries to move up and down within the test chamber 1. When the lifting bracket 34 approaches the highest or lowest point of its stroke, the first limit module 35 is triggered, sending a signal to the control unit 5 or physically preventing it from continuing to move. The combined effect of these components is to enable the wafer 7 to complete high-precision, highly repeatable vertical lifting motion according to control commands in a vacuum environment, and to ensure that the motion process is carried out within the set safe stroke range, providing a basic motion guarantee for the positioning accuracy and stability of the test wafer 7.

[0044] In a specific embodiment, the lifting and rotating unit 4 includes a lifting drive module 41, which includes a second motor 411, a first reducer 412, a second coupling 413, a lifting slide rail 414, and a wafer carrier 415. The output end of the second motor 411 is coaxially connected to the input end of the first reducer 412 through the second coupling 413. The output end of the first reducer 412 is connected to the lifting slide rail 414. The wafer carrier 415 is fixed on the slider of the lifting slide rail 414 and moves vertically up and down along the lifting slide rail 414. The upper and lower stroke endpoints of the lifting slide rail 414 are respectively provided with second limit modules 416. The second motor 411 is a servo motor. The lifting slide rail 414 is fixed on a support member 417.

[0045] The second motor 411 is installed outside or at the bottom of the test chamber 1. Its output shaft is coaxially connected to the input shaft of the first reducer 412 via a second coupling 413. The output shaft of the first reducer 412 is connected to the drive shaft of the lifting slide rail 414. The main body of the lifting slide rail 414 is fixed to the bottom of the test chamber 1. The wafer carrier 415 is installed on the slider of the lifting slide rail 414 and moves vertically up and down inside the test chamber 1 together with the slider. The second limit modules 416 are respectively located near the top and bottom endpoints of the travel of the lifting slide rail 414. The function of the second motor 411 is to provide the original power required for the lifting motion. The function of the first reducer 412 is to reduce the output speed of the second motor 411 while increasing the output torque to meet the requirements of the lifting motion for greater driving force and smoother speed. The function of the second coupling 413 is to connect the output shaft of the second motor 411 with the input shaft of the first reducer 412, transmit torque, and compensate for possible installation deviations. The function of the lifting slide rail 414 is to convert the motion output by the first reducer 412 into precise and stable linear lifting motion, and to provide guidance for the wafer carrier 415. The function of the wafer carrier 415 is to directly support and fix the wafer to be tested, serving as a platform for the wafer's lifting motion.

[0046] When the wafer needs to be driven for lifting and lowering, the second motor 411 rotates according to the instructions of the control unit 5. Its rotational motion is transmitted to the first reducer 412 via the second coupling 413. The first reducer 412 reduces the input speed and increases the torque, driving the drive shaft of the lifting slide rail 414 to rotate. The lifting slide rail 414 converts this rotational motion into the vertical linear motion of its slider. The wafer holder 415, fixed to the slider, moves precisely up and down within the test chamber 1. A second limit module in the stroke ensures that the movement does not exceed the set safety range. These components, combined, provide the lifting and rotating unit 4 with powerful, smooth, and precisely controllable vertical lifting and lowering capabilities, ensuring that the wafer reaches and stabilizes in the required vertical position during testing, laying the foundation for evaluating its positioning accuracy and stability under combined motion.

[0047] In a specific embodiment, the lifting and rotating unit 4 further includes a rotating drive module 42, which includes a third motor 421, a second reducer 422, and a third coupling 423. The output end of the third motor 421 is coaxially connected to the input end of the second reducer 422 through the third coupling 423. The output end of the second reducer 422 is fixed to the wafer carrier 415, and the wafer carrier 415 is connected to the top of the slider of the lifting slide rail 414.

[0048] The third motor 421, the second reducer 422, and the third coupling 423 are mounted as a whole on the top of the slider of the lifting slide rail 414. Specifically, the output shaft of the third motor 421 is coaxially connected to the input shaft of the second reducer 422 via the third coupling 423. The output shaft of the second reducer 422 is directly and fixedly connected upwards to the wafer carrier 415 located above it. Therefore, the entire rotary drive module 42 moves up and down with the slider of the lifting slide rail 414. The function of the third motor 421 is to provide the original rotational power required for the wafer rotation. The function of the second reducer 422 is to reduce the output speed of the third motor 421 while increasing the output torque to meet the requirements of more precise speed control and driving force required for the wafer rotation. The function of the third coupling 423 is to connect the output shaft of the third motor 421 and the input shaft of the second reducer 422, transmit rotational torque, and compensate for any minor installation deviations that may exist between them, ensuring smooth power transmission.

[0049] When the wafer needs to be driven to rotate, the third motor 421 starts rotating according to the command of the control unit 5. Its rotational motion is transmitted to the input shaft of the second reducer 422 via the third coupling 423. The second reducer 422 reduces the input speed and increases the torque, and its output shaft drives the wafer carrier 415, which is fixedly connected to it, to rotate. This configuration allows the wafer carrier 415 to achieve precise and controllable rotational motion while moving up and down with the lifting slide rail 414. This provides the test platform with the ability to simulate the combined motion mode of wafer lifting and rotating in a vacuum environment, thus enabling a comprehensive evaluation of the performance of the lifting and rotating unit under such complex real-world conditions.

[0050] In a specific embodiment, the rotary drive module 42 further includes a bellows 424 and a rotary seal 425. The bellows 424 seals and covers the lifting slide rail 414, and the rotary seal 425 is located at the rotation axis of the wafer carrier 415.

[0051] The main function of the bellows 424 is to dynamically seal the movement gap between the slider and the fixed base through its own expansion and contraction deformation when the slider of the lifting slide rail 414 moves up and down, preventing the vacuum environment of the test chamber 1 from leaking due to the movement of the slider, and at the same time protecting the internal mechanism of the lifting slide rail 414 from contamination by process gases that may be present in the chamber. The main function of the rotary seal 425 is to form a reliable dynamic seal at the contact interface between the rotating shaft and the fixed support component when the wafer carrier 415 rotates, preventing vacuum or process gases from leaking along the gap of the rotating shaft and ensuring the stability of the chamber pressure during the rotation.

[0052] When the slider of the lifting slide rail 414 moves the wafer carrier 415 up and down, the bellows 424 expands and contracts synchronously, always tightly covering and sealing the annular gap between the slider's movement path and the fixed base. Simultaneously, when the third motor 421 drives the wafer carrier 415 to rotate, the rotary seal 425 continuously operates at the root of its rotating shaft, forming an effective rotary dynamic seal. The combined effect of these two actions is that during the simultaneous or separate lifting and rotating movements of the wafer carrier 415, dual dynamic sealing is provided for the moving parts of the lifting and rotating unit 4. This effectively isolates the gas exchange channel between the moving parts and the internal environment of the test chamber 1, ensuring that the high vacuum or specific process gas atmosphere inside the test chamber 1 can be maintained stably for a long time, unaffected by the internal movement of the unit. This creates a reliable and stable environmental foundation for the accurate testing of wafer lifting and rotating performance in a real vacuum / gas environment.

[0053] In a specific embodiment, the position detection unit 2 includes at least two laser ranging modules disposed above the wafer. Each laser ranging module includes a laser emitter 21, a laser receiver 22, and a processor 23. The laser emitter emits detectable laser light onto the wafer, the laser receiver 22 receives diffusely reflected laser light from the wafer surface, and the processor 23 calculates the real-time position and tilt of the wafer based on the laser reflection time difference. The processor 23 is configured to: determine that the wafer has shifted position when the position difference between two detection points is greater than 0.1 mm; and determine that the repeatability accuracy is unqualified when the position deviation before and after lifting is greater than ±0.1 mm.

[0054] A laser emitter 21 and its paired laser receiver 22 together constitute a laser ranging module. They are fixedly installed in pairs at specific positions inside and above the test cavity 1, typically directly above the wafer carrier, with their laser beams projected vertically downwards onto the wafer surface. The processor 23 can be integrated inside each laser ranging module, or installed as an external independent unit outside the test cavity 1, or integrated into the control unit 5. The laser emitter 21 and laser receiver 22 of each laser ranging module are connected to the corresponding processor 23 via cables to transmit laser emission and reception signals and processing results. The processor 23 ultimately transmits wafer position and tilt information to the control unit 5 via a data line. The laser emitter 21 emits a laser beam of a specific wavelength, vertically illuminating the test point on the wafer below. The laser receiver 22 receives the diffusely reflected laser signal from the wafer surface. The processor 23 is responsible for precisely controlling the emission timing of the laser emitter 21, recording the time difference between the laser beam being emitted and received by the laser receiver 22, and calculating the real-time distance (i.e., the height of the wafer at that point) from the laser emitter 21 to the measured point on the wafer based on the speed of light. At the same time, when using at least two modules, the processor 23 will compare the height data of different detection points to calculate the tilt angle of the wafer.

[0055] Each laser ranging module operates independently: its laser emitter 21 emits a laser pulse to illuminate a point on the wafer surface, and the diffusely reflected light from that point is captured by the corresponding laser receiver 22. The processor 23 accurately measures the flight time between the emission and reception of the laser pulse and calculates the absolute distance from that point to the laser ranging module using the principle of the constant speed of light. When at least two such modules are configured to measure the position and height of different points on the wafer, the processor 23 can calculate the real-time overall height change of the wafer and the tilt angle of the wafer plane relative to the horizontal plane by comparing the height values ​​of these points. The combined operation enables non-contact, high-precision, and real-time dynamic monitoring of the wafer's position, height, and stability during lifting and / or rotational movements in a vacuum environment, providing direct and quantitative data for evaluating the repeatability and motion stability of the lifting mechanism.

[0056] The processor 23 is programmed with specific judgment thresholds: when the wafer is at a stationary or moving target position, if the height difference between two simultaneously measured different detection points (e.g., two symmetrical points on the wafer edge) exceeds 0.1 mm, the processor 23 determines that the wafer has tilted or shifted position, indicating a problem with motion stability or a deviation in the mechanism. Furthermore, when testing the wafer's repeatability, if the processor 23 detects that the deviation between the actual reached position (height) and the target position (or the maximum deviation range after multiple attempts) exceeds the set ±0.1 mm tolerance range after the wafer is instructed to move up and down multiple times to the same theoretical target position, the processor 23 determines that the repeatability of the lifting mechanism is unqualified, indicating that its motion accuracy is substandard.

[0057] In a specific embodiment, the control unit 5 is configured to: perform more than one million cycle tests on the single lifting unit 3 or the lifting and rotating unit 4; record the position data after each lifting and lowering, and calculate the repeatability accuracy.

[0058] Control unit 5 is configured to perform high-intensity durability tests on the single lifting unit 3 or the lifting-rotating unit 4 installed in test chamber 1, driving the wafer it carries to perform more than 1 million continuous lifting motion cycles (for the lifting-rotating unit 4, this may include composite lifting cycles with rotation). After each lifting cycle, control unit 5 receives and records in real time the height data of the actual position reached by the wafer measured by position detection unit 2. Based on this massive amount of position data accumulated over a long period, control unit 5 statistically analyzes the repeatability accuracy of the wafer at the set target position. Specifically, it quantifies the degree of position stability decay of the lifting mechanism after long-term operation by calculating the maximum deviation range of the actual position reached in multiple cycles for the same target position (e.g., the difference between the maximum and minimum values).

[0059] In a specific embodiment, the single lifting unit 3 and the lifting and rotating unit 4 can be interchangeably installed at the bottom of the test chamber 1 via a quick-release structure.

[0060] A quick-release structure may be a mechanical interface designed to enable rapid installation and removal of the unit, such as using a precision flange with locating pins and guide grooves in conjunction with pneumatic or manual locking clips, or using a standardized modular base with pre-tensioned bolts. This structure allows operators to precisely align, physically fix, and establish necessary electrical / pneumatic connections between the single lifting unit 3 or the lifting and rotating unit 4 and the corresponding interface at the bottom of the test chamber 1 via its bottom base, without complex tools or prolonged operation, and to quickly separate and replace it when needed.

[0061] The single lifting unit 3 and the lifting-rotating unit 4 are interchangeably mounted at the bottom of the test chamber 1 via a quick-release structure to achieve the versatility and efficiency of the test platform. This design allows users to quickly switch between installing the corresponding functional units within the same test chamber 1 according to specific testing needs. This avoids the enormous cost of constructing an entire test chamber and environmental system separately for each motion mode, ensuring that both test modes are conducted under identical vacuum environments, position detection benchmarks, and control conditions. This makes the performance test results (such as repeatability and long-term attenuation) of the single lifting unit 3 and the lifting-rotating unit 4 directly comparable, greatly improving testing efficiency and data consistency.

[0062] In a specific embodiment, the first limit module 35 is a limit switch or a photoelectric sensor.

[0063] The testing process of the wafer lifting structure test platform is as follows: First, select either a single lifting unit 3 or a lifting and rotating unit 4 according to the testing requirements, and fix it to the base at the bottom of the test chamber 1 using a quick-release structure. After closing the chamber, the control unit 5 starts the external vacuum pump to evacuate the test chamber 1 through the vacuum pump connection port 11. At the same time, the vacuum gauge 13 monitors the pressure data in real time and feeds it back to the control unit. When the target vacuum level is reached, a specific process gas can be injected as needed through the backfill gas connection port 12. Control unit 5 sends instructions to the selected unit: If testing single lifting unit 3, the first motor 31 drives the linear slide rail 32 through the first coupling 33, causing the lifting bracket 34 to perform vertical lifting motion, and the first limit module 35 ensures safe travel; if testing lifting and rotating unit 4, the second motor 411 drives the lifting slide rail 414 through the second coupling 413 and the first reducer 412 to achieve the lifting motion of the wafer bracket, while the third motor 421 drives the wafer bracket 415 to rotate through the third coupling 423 and the second reducer 422. At this time, the bellows 424 extends and retracts with the slider of the lifting slide rail 414 to maintain vacuum sealing, and the rotating seal 425 ensures dynamic sealing at the rotating shaft. During the movement, at least two laser ranging modules work continuously: their laser emitters project lasers onto the wafer surface, the laser receivers capture diffuse reflection signals, and the processor calculates the real-time height and wafer tilt of each detection point. Control unit 5 records position data after each motion cycle. When the height difference between two points exceeds 0.1mm, it determines that the position has deviated. When the lifting position deviation exceeds ±0.1mm, it determines that the repeatability accuracy is unqualified. Finally, through more than 1 million cycle tests, the long-term position stability, repeatability accuracy, and sealing reliability of the lifting mechanism in vacuum and process gas environments are comprehensively evaluated.

[0064] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A test platform for a wafer lifting structure, characterized in that, The testing platform includes a test chamber capable of simulating a vacuum environment, a position detection unit, a single lifting unit, a lifting and rotating unit, and a control unit. The position detection unit is located in the test chamber for real-time detection of the wafer's displacement and tilt. The single lifting unit is installed at the bottom of the test chamber for driving the wafer to move up and down. The lifting and rotating unit is installed at the bottom of the test chamber for driving the wafer to rotate and move up and down simultaneously. The control unit is connected to the position detection unit and is used to calculate the wafer's repeatability and stability based on the detection data. The single lifting unit and the lifting and rotating unit can be switched between installations.

2. The test platform for the wafer lifting structure according to claim 1, characterized in that, The test chamber has a vacuum pump connection port and a backfill gas connection port. The test chamber is connected to an external vacuum pump through the vacuum pump connection port, and the test chamber is connected to a process gas backfill pipeline through the backfill gas connection port. The test chamber contains a vacuum gauge, which is installed on the inner wall of the test chamber and is used to monitor the chamber pressure in real time and transmit the data to the control unit.

3. The test platform for the wafer lifting structure according to claim 1, characterized in that, The single lifting unit includes a first motor, a linear slide rail, a first coupling, a lifting bracket, and a first limiting module. The output end of the first motor is connected to the linear slide rail through the first coupling. The lifting bracket is fixed on the slider of the linear slide rail to support the test wafer. The first limiting module is located at the end of the stroke of the linear slide rail.

4. The test platform for the wafer lifting structure according to claim 1, characterized in that, The lifting and rotating unit includes a lifting drive module, which includes a second motor, a first reducer, a second coupling, a lifting slide rail, and a wafer carrier. The output end of the second motor is coaxially connected to the input end of the first reducer through the second coupling. The output end of the first reducer is connected to the lifting slide rail. The wafer carrier is fixed on the slider of the lifting slide rail and moves vertically up and down along the lifting slide rail. The upper and lower stroke endpoints of the lifting slide rail are respectively provided with second limit modules.

5. The test platform for the wafer lifting structure according to claim 4, characterized in that, The lifting and rotating unit also includes a rotating drive module, which includes a third motor, a second reducer, and a third coupling. The output end of the third motor is coaxially connected to the input end of the second reducer through the third coupling. The output end of the second reducer is fixed to the wafer carrier, and the wafer carrier is connected to the top of the slider of the lifting slide rail.

6. The test platform for the wafer lifting structure according to claim 5, characterized in that, The rotary drive module also includes a bellows and a rotary seal. The bellows seals and covers the lifting slide rail, and the rotary seal is located at the rotation axis of the wafer carrier.

7. The test platform for the wafer lifting structure according to claim 1, characterized in that, The position detection unit includes at least two laser ranging modules disposed above the wafer. Each laser ranging module includes a laser emitter, a laser receiver, and a processor. The laser emitter emits a detectable laser onto the wafer, the laser receiver receives diffusely reflected laser light from the wafer surface, and the processor calculates the real-time position and tilt of the wafer based on the laser reflection time difference. The processor is configured to: determine that the wafer has shifted position when the position difference between two detection points is greater than 0.1 mm; and determine that the repeatability accuracy is unqualified when the position deviation before and after lifting is greater than ±0.1 mm.

8. The test platform for the wafer lifting structure according to claim 7, characterized in that, The control unit is configured to perform more than one million cyclic tests on the single lifting unit or the lifting and rotating unit; record the position data after each lifting and lowering, and calculate the repeatability accuracy.

9. The test platform for the wafer lifting structure according to claim 1, characterized in that, The single lifting unit and the lifting and rotating unit can be interchangeably installed at the bottom of the test chamber via a quick-release structure.

10. The test platform for the wafer lifting structure according to claim 3, characterized in that, The first limit module is a limit switch or a photoelectric sensor.

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