High-precision mechanical guide rail linear motion platform for semiconductor

Abstract

The application relates to the technical field of precision motion control, and discloses a high-precision mechanical guide rail linear motion platform for semiconductors, which comprises a base, the top surface of the base is fixedly connected with an X linear motor, the output end of the X linear motor is fixedly connected with a first support base, the bottom of the first support base is fixedly connected with not less than one sliding block, the top of the base is fixedly connected with not less than one X guide rail, the sliding block is slidably connected to the surface of the X guide rail, the top of the first support base is fixedly connected with a Y guide rail, the surface of the Y guide rail is slidably connected with a second support base, the top of the first support base is provided with a Y linear motor, and the output end of the Y linear motor is fixedly connected to the inside of the second support base. The first support base and the second support base are directly driven by adopting the coreless linear motor, and the full-closed loop position feedback is carried out by cooperating with a grating ruler and a reading head, so that higher positioning precision and dynamic response performance are realized.

Description

Technical Field

[0001] This invention relates to the field of precision motion control technology, specifically to a high-precision mechanical guide linear motion platform for semiconductors. Background Technology

[0002] High-precision linear motion platforms play a crucial role in semiconductor manufacturing, optical inspection, biomedicine, and other fields. The main function of a high-precision linear motion platform is to support workpieces or functional components and enable them to achieve precise positioning and high-speed, stable movement at the micron or even nanometer level within a specified coordinate system. In the semiconductor industry, whether it is wafer lithography and etching or mask and chip inspection and packaging, all rely heavily on the high precision, high stability, and high cleanliness of the motion performance provided by linear motion platforms.

[0003] Existing high-precision linear motion platforms employ a drive scheme using rotary motors and mechanical transmission mechanisms. The power source is a rotary servo motor, and the rotational motion of the motor is converted into the linear motion of the platform through transmission components such as couplings and ball screws. The position control of the entire system relies on indirect measurement by a rotary encoder installed on the rear side of the motor shaft. The controller controls the rotation of the motor by comparing the feedback value of the encoder with the target value, thereby indirectly controlling the final position of the platform.

[0004] However, existing high-precision linear motion platforms introduce friction, wear, and backlash, which reduces the positioning accuracy of the system. At the same time, the indirect measurement method relying on the encoder at the end of the motor cannot compensate for errors caused by processing errors, elastic deformation, and thermal effects in the transmission chain in real time, resulting in a deviation between the actual movement position of the platform and the commanded position. Therefore, this invention proposes a high-precision mechanical guide linear motion platform for semiconductors to solve the shortcomings of the existing technology. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a high-precision mechanical guide linear motion platform for semiconductors, which solves the problem that transmission and measurement errors introduced in existing technologies cannot be compensated in real time, resulting in low platform positioning accuracy, slow dynamic response, and poor long-term stability.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-precision mechanical guide rail linear motion platform for semiconductors, characterized in that it comprises: a base, an X-linear motor fixedly connected to the top surface of the base, a first support fixedly connected to the output end of the X-linear motor, at least one slider fixedly connected to the bottom of the first support, at least one X-guide rail fixedly connected to the top of the base, the slider slidably connected to the surface of the X-guide rail, a Y-guide rail fixedly connected to the top of the first support, a second support slidably connected to the surface of the Y-guide rail, a Y-linear motor disposed on the top of the first support, the output end of the Y-linear motor fixedly connected inside the second support, a lifting platform disposed on the top of the second support, a rotating seat disposed on the top of the lifting platform, and a controller mounted on the top of the second support, the controller integrating a guide rail linear motion control system for receiving control commands from a host computer and generating control signals and real-time position feedback, performing unified coordination of each motion axis, and achieving high-precision synchronous motion and accurate positioning.

[0007] Preferably, the slider has multiple sliding steel balls inside, which are slidably connected to the surface of the X-guide rail. Both ends of the slider are fixedly connected to sealing gaskets, which are slidably connected to the surface of the X-guide rail.

[0008] Preferably, an X-type cleanroom cable chain is fixedly connected to the top left side of the base, and a Y-type cleanroom cable chain is fixedly connected to the top rear side of the first support base. Both the X-type and Y-type cleanroom cable chains are provided with cable chain sleeves.

[0009] Preferably, the lifting platform is equipped with a Z linear motor and a cylinder, and the X linear motor is a combination of two linear motors.

[0010] Preferably, the sliding steel ball is set at an angle, the steel balls in the sliding steel ball are connected by a ball retainer, and the side wall of the X guide rail has an arc groove shape structure, the arc groove matching the sliding steel ball.

[0011] Preferably, the guide rail linear motion control system includes:

[0012] Multiple drivers are connected to the controller to receive control signals;

[0013] Multiple linear motors are used to receive drive current from the driver;

[0014] Multiple grating rulers are used to measure the distance of movement along each axis;

[0015] Multiple reading heads are used to read the original position information of the multiple grating rulers;

[0016] Multiple subdivision boxes, the input terminals of which are connected to the multiple reading heads.

[0017] Preferably, the controller is electrically connected to the X linear motor, the Y linear motor, the lifting platform, and the rotating seat, respectively.

[0018] Preferably, the controller is an EtherCAT master station, which is connected to multiple drives via an Ethernet control automation technology bus.

[0019] Preferably, the subdivision box output is connected to the controller to process the raw position information of the reading head and provide a position feedback signal to the controller.

[0020] Preferably, at least one of the multiple drivers is a dual-channel driver, wherein the two channels of the dual-channel driver synchronously control the two linear motors in the X linear motor, and the multiple reading heads and multiple subdivision boxes include two sets corresponding to the two linear motors in the X linear motor, and provide independent feedback signals to the controller.

[0021] This invention provides a high-precision mechanical guide linear motion platform for semiconductors. It has the following advantages:

[0022] 1. This invention achieves higher positioning accuracy and dynamic response performance by using a coreless linear motor to directly drive the first and second support seats, and by using a grating ruler and reading head for full closed-loop position feedback. Compared with the prior art, this structure eliminates mechanical transmission components such as ball screws, thus eliminating errors caused by transmission gaps, friction and wear. At the same time, the feedback method of directly measuring the actual position of the platform enables the controller to compensate for various errors in real time, thereby ensuring high precision and high stability of the platform movement.

[0023] 2. This invention constructs a high-rigidity, low-friction guide for the first support seat by setting multiple circulating sliding steel balls inside the slider and cooperating with the precision-machined arc-shaped grooves on the X-guide rail. The rolling contact of the sliding steel balls reduces the frictional resistance of the first support seat during movement, ensuring the smoothness of the platform during start-up, shutdown, and operation. At the same time, the structure of the arc-shaped grooves and steel balls increases the contact area, improving the guiding stiffness and load-bearing capacity of the X-guide rail, making the platform less prone to deformation when moving at high speed or under load, and providing stable and reliable mechanical support for precision positioning.

[0024] 3. This invention effectively meets the requirements of high-level clean environments such as semiconductor manufacturing by using X-type and Y-type cleanroom cable chains to store power supply and signal cables. The non-contact drive method of the coreless linear motor itself has no mechanical wear. Combined with the specially designed cleanroom cable chain to constrain and protect the cables, it avoids the generation of micro-dust particles due to friction during the movement, ensuring the high cleanliness and high reliability of the entire system under high-speed reciprocating motion. Attached Figure Description

[0025] Figure 1 This is a perspective view of the present invention;

[0026] Figure 2 This is a schematic diagram of the sliding steel ball of the present invention;

[0027] Figure 3 This is a schematic diagram of the Y-type dust-free cable chain of the present invention;

[0028] Figure 4 This is a schematic diagram of the controller of the present invention;

[0029] Figure 5 This is a block diagram of the control system principle of the present invention;

[0030] Figure 6 This is the overall electrical block diagram of the present invention;

[0031] Figure 7 This is a schematic diagram of the feedback of the grating ruler of the present invention;

[0032] Figure 8 This is a schematic diagram of the X-axis motor drive control of the present invention.

[0033] Legend

[0034] 1. Base; 2. X linear motor; 3. First support seat; 4. Slider; 5. Sliding steel ball; 6. Sealing gasket; 7. X guide rail; 8. X cleanroom cable chain; 9. Y guide rail; 10. Second support seat; 11. Y linear motor; 12. Y cleanroom cable chain; 13. Controller; 14. Lifting platform; 15. Rotating seat. Detailed Implementation

[0035] 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 scope of protection of the present invention.

[0036] Please see Figures 1-8This invention provides a high-precision mechanical guide linear motion platform for semiconductors, comprising: a base 1, which provides stable and reliable support for the entire mechanical guide linear motion platform; an X-linear motor 2 fixedly connected to the top surface of the base 1, the X-linear motor 2 being two coreless T9-2M model linear motors forming a gantry-type drive structure; a first support 3 fixedly connected to the output end of the X-linear motor 2, which can drive the first support 3 to perform stable movement; and at least one slider 4 fixedly connected to the bottom of the first support 3. The slider 4 can move stably under the drive of the X linear motor 2. At least one X guide rail 7 is fixedly connected to the top of the base 1. The slider 4 is slidably connected to the surface of the X guide rail 7. The X guide rail 7 is a precision-machined linear guide rail, providing stable guidance for the slider 4's movement. A Y guide rail 9 is fixedly connected to the top of the first support base 3. The installation direction of the Y guide rail 9 is perpendicular to the direction of the X guide rail 7, together forming the XY plane motion reference direction of the platform. A second support base 10 is slidably connected to the surface of the Y guide rail 9, serving as a moving component on the surface of the Y guide rail 9. The first support base 3 is equipped with a Y-linear motor 11 on its top. The output end of the Y-linear motor 11 is fixedly connected inside the second support base 10. The Y-linear motor 11 is a coreless linear motor of model UL9N, used to drive the second support base 10 to move linearly along the Y-guide rail 9. The second support base 10 is equipped with a lifting platform 14 on its top. The lifting platform 14 is a CDZWS-10-A Z-axis module, which integrates an independent linear motor and cylinder for precise vertical lifting. The top of the lifting platform 14 is equipped with... A rotating base 15 is provided, which is a DMN71G T-axis module used to achieve precise rotation or angular positioning in the horizontal plane. A controller 13 is installed on the top of the second support base 10. The controller 13 adopts an SP+EC controller and integrates an Ethernet control automation technology master station, which can coordinate and control up to 8 motion axes. The controller 13 integrates a guide rail linear motion control system, which is used to receive control commands from the host computer and generate control signals and real-time position feedback to coordinate all motion axes and achieve high-precision synchronous motion and accurate positioning.

[0037] Please see Figures 1-2 The slider 4 has multiple sliding steel balls 5 inside, which are slidably connected to the surface of the X guide rail 7. When the slider 4 moves, the sliding steel balls 5 roll along a precise circulation loop, thereby converting the sliding friction of the slider 4 into the rolling friction of the sliding steel balls 5. Both ends of the slider 4 are fixedly connected to sealing gaskets 6, which are slidably connected to the surface of the X guide rail 7. The cutting edge of the sealing gasket 6 is tightly fitted to the surface of the X guide rail 7, which can effectively prevent external dust from entering the interior of the slider 4 and prevent any small particles that may be generated inside from leaking out.

[0038] Please see Figure 1 , Figure 3 An X-type cleanroom cable chain 8 is fixedly connected to the top left side of the base 1. One end of the X-type cleanroom cable chain 8 is fixed to the base 1, and the other end moves with the first support 3. It is used to store the power supply and signal cables of the X-type linear motor 2. A Y-type cleanroom cable chain 12 is fixedly connected to the top rear side of the first support 3. The Y-type cleanroom cable chain 12 is used to store all the power supply and signal cables of the Y-type linear motor 11, the lifting platform 14, and the rotating seat 15. Both the X-type cleanroom cable chain 8 and the Y-type cleanroom cable chain 12 are equipped with cable chain sleeves. Both the X-type cleanroom cable chain 8 and the Y-type cleanroom cable chain 12 are low-dust products designed specifically for cleanrooms. The cable chain sleeves can further enhance the wear resistance of the X-type cleanroom cable chain 8 and the Y-type cleanroom cable chain 12 and further reduce the risk of micro-dust generation.

[0039] Please see Figure 1 , Figure 3 , Figure 4 The lifting platform 14 is equipped with a Z linear motor, which can directly drive the lifting part of the lifting platform 14 to achieve fast and accurate vertical positioning. The lifting platform 14 is equipped with a cylinder, which can be used to balance the Z-axis moving parts by gravity or provide braking function when the power is off, thus improving the safety of lifting. The X linear motor 2 is composed of two linear motors. The two coreless linear motors of model T9-2M are arranged side by side on both sides of the X guide rail 7 to form a gantry-type dual drive structure, which improves the driving torque and motion stability of the first support platform in the X-axis direction. The load weight of the X-axis is about 130kg and the running acceleration is 1G, according to the modeling calculation.

[0040] Required thrust: F = ma + F 摩擦 =120*9.8+30=1206N;

[0041] Due to space constraints, dual linear motors are selected for driving, so the thrust required for a single motor is 603N.

[0042] Please see Figure 2 The sliding steel balls 5 are set at an angle. This angled arrangement allows the sliding steel balls 5 to bear loads from multiple directions simultaneously. The steel balls in the sliding steel balls 5 are connected by ball retainers. The ball retainers ensure that the sliding steel balls 5 are arranged at equal intervals, preventing collisions and abnormal friction between the sliding steel balls 5, making the sliding steel balls 5 move more smoothly when following the slider 4. The side wall of the X guide rail 7 has an arc groove shape structure. The arc groove matches the curvature of the sliding steel balls 5. The four action directions (radial, anti-radial, and lateral) on the slider 4 all have the same rated load, thereby ensuring low friction when the slider 4 slides, while also improving the contact stiffness and load-bearing capacity of the X guide rail 7.

[0043] Please see Figure 5-8 The guide rail linear motion control system includes: multiple drivers connected to controller 13 for receiving control signals. The drivers include one SP+EC-08080864NNNDNDNNACS driver for controlling motion in the X, Y, Z, and T axes; one UDMxa2B20TNTNNNACS driver for controlling motion in the X and Y axes; and one UDMPM200521N0Y1 driver. S controls the movement along the Z and T axes; the driver, acting as a power amplifier, converts the weak control signals from the controller 13 into the large current required to drive the linear motors; multiple linear motors, which receive the drive current from the driver (i.e., coreless linear motors), act as actuators, directly converting electrical energy into mechanical energy for linear motion along the X, Y, Z, and T axes; multiple grating rulers, made of Renishaw RKLC20-S series stainless steel strip, are used to measure the distance of movement along each axis. After being securely fixed to the machine shafts, the grating rulers expand and contract with the machine body according to its thermal expansion coefficient and characteristics, minimizing the difference in movement between the rulers and the machine. It achieves excellent measurement performance through simplified system thermal expansion compensation, and can directly engrave the IN-TRAC optical reference zero point on the incremental scale markings of the grating ruler to provide position indication and facilitate automatic phase adjustment. Multiple reading heads are used to read the original position information of multiple grating rulers. The reading heads are T1030-15A reading heads, which are mounted on the surface of moving parts and scan the scale on the surface of the grating ruler non-contactly. Multiple subdivision boxes are connected to the input terminals of multiple reading heads. The subdivision boxes are Ti0000A00A subdivision boxes, which can perform high-magnification electronic subdivision of the analog signals or low-resolution digital signals output by the reading heads, thereby improving the position measurement resolution of the system.

[0044] Please see Figure 6 The controller 13 is electrically connected to the X linear motor 2, the Y linear motor 11, the lifting platform 14, and the rotating seat 15 respectively. The controller 13 can drive the X linear motor 2, the Y linear motor 11, the lifting platform 14, and the rotating seat 15 to run, thereby realizing movement in the X, Y, Z, and T axis directions.

[0045] Please see Figure 6 The controller 13 is an EtherCAT master station for Ethernet control automation technology. The controller 13 is connected to multiple drives through the Ethernet control automation technology bus. The connection between the bus and multiple drives enables high-speed, real-time, and deterministic data exchange between the controller 13 and all drives, ensuring precise synchronization of multi-axis motion.

[0046] Please see Figure 7The subdivision box output is connected to the controller 13 to process the raw position information of the reading head and provide a position feedback signal to the controller 13. The high-resolution digital position signal output by the subdivision box can be directly fed back to the position feedback interface of the controller 13.

[0047] Please see Figure 8 At least one of the multiple drivers is a dual-channel driver. The two channels of the dual-channel driver synchronously control the two linear motors in X linear motor 2. The dual-channel driver can adapt to the synchronous control algorithm of the gantry drive structure composed of the two linear motors in X linear motor 2. The controller 13 sends a synchronization command to the channel driver to realize the operation of the gantry drive structure composed of the two linear motors in X linear motor 2. The multiple reading heads and multiple subdivision boxes include two sets corresponding to the two linear motors in X linear motor 2. These two independent feedback systems measure the actual positions on both sides of the gantry structure and provide independent feedback signals to the controller 13. The controller 13 uses these two independent feedback signals to calculate the yaw error of the platform in real time and generates a differential compensation command to the two linear motors in X linear motor 2, thereby actively correcting the yaw in the X-axis direction to ensure the high dynamic synchronization accuracy of the platform.

[0048] Working Principle: The working process of this device begins with the controller 13 receiving control commands from the host computer, converting the control commands into motion commands for each axis, and transmitting them to the corresponding drivers for each axis. For the horizontal movement of the X-axis, the controller 13 outputs a drive signal to the X linear motor 2 mounted on the base 1. The X linear motor 2 drives the slider 4 to move along the X guide rail 7. Inside the guide rail, the slider 4 achieves low-friction movement through the circulating sliding steel balls 5, and the sealing gaskets 6 at both ends provide protection. The movement of the slider 4 drives the first support seat 3 to move axially in the X direction. For the scanning motion of the Y-axis, the controller 13 drives the Y linear motor 11 mounted on the second support seat 10 in the same way, causing the second support seat 10 to move along the Y guide rail 9. During the movement along the Y-axis, the cables supplying power and transmitting signals to the moving parts are respectively stored in the X cleanroom cable chain 8 and the Y cleanroom cable chain 12 to ensure reliable power supply and signal transmission for the moving parts in a clean environment. At the top of the platform, the controller 13 commands the lifting platform 14 to complete the vertical lifting of the Z-axis and commands the rotating seat 15 to execute the rotation of the T-axis. In order to achieve closed-loop control, the reading heads installed on each linear axis will read the precise position of the grating ruler in real time and continuously feed this actual position data back to the controller 13. The controller 13 adjusts the drive commands to the X linear motor 2 and the Y linear motor 11 in an instant by comparing the deviation between the command position and the actual position to correct the error, thereby forming a complete work cycle of command, drive, motion, measurement, and correction.

Claims

1. A high-precision mechanical guide linear motion platform for semiconductors, characterized in that, include: A base (1) is provided, with an X-linear motor (2) fixedly connected to its top surface. A first support (3) is fixedly connected to the output end of the X-linear motor (2). At least one slider (4) is fixedly connected to the bottom of the first support (3). At least one X-guide rail (7) is fixedly connected to the top of the base (1). The slider (4) is slidably connected to the surface of the X-guide rail (7). A Y-guide rail (9) is fixedly connected to the top of the first support (3). A second support (10) is slidably connected to the surface of the Y-guide rail (9). A Y linear motor (11) is provided on the top of the support base (3). The output end of the Y linear motor (11) is fixedly connected inside the second support base (10). A lifting platform (14) is provided on the top of the second support base (10). A rotating seat (15) is provided on the top of the lifting platform (14). A controller (13) is installed on the top of the second support base (10). The controller (13) integrates a guide rail linear motion control system, which is used to receive control commands from the host computer and generate control signals and real-time position feedback to coordinate the motion axes.

2. The high-precision mechanical guide linear motion platform for semiconductors according to claim 1, characterized in that, The slider (4) is provided with a plurality of sliding steel balls (5), which are slidably connected to the surface of the X guide rail (7). Both ends of the slider (4) are fixedly connected with sealing gaskets (6), which are slidably connected to the surface of the X guide rail (7).

3. The high-precision mechanical guide linear motion platform for semiconductors according to claim 1, characterized in that, An X-type dust-free cable chain (8) is fixedly connected to the top left side of the base (1), and a Y-type dust-free cable chain (12) is fixedly connected to the top rear side of the first support base (3). Both the X-type dust-free cable chain (8) and the Y-type dust-free cable chain (12) are provided with cable chain sleeves.

4. The high-precision mechanical guide linear motion platform for semiconductors according to claim 1, characterized in that, The lifting platform (14) is equipped with a Z linear motor and a cylinder. The X linear motor (2) is composed of two linear motors.

5. The high-precision mechanical guide linear motion platform for semiconductors according to claim 2, characterized in that, The sliding steel ball (5) is set at an angle, and the steel balls in the sliding steel ball (5) are connected by a ball retainer. The side wall of the X guide rail (7) is a circular arc groove structure, and the circular arc groove matches the sliding steel ball (5).

6. The high-precision mechanical guide linear motion platform for semiconductors according to claim 1, characterized in that, The linear motion control system for the guide rail includes: Multiple drivers are connected to the controller (13) for receiving control signals; Multiple linear motors are used to receive drive current from the driver; Multiple grating rulers are used to measure the distance of movement along each axis; Multiple reading heads are used to read the original position information of the multiple grating rulers; Multiple subdivision boxes, the input terminals of which are connected to the multiple reading heads.

7. The high-precision mechanical guide linear motion platform for semiconductors according to claim 6, characterized in that, The controller (13) is electrically connected to the X linear motor (2), the Y linear motor (11), the lifting platform (14), and the rotating seat (15), respectively.

8. The high-precision mechanical guide linear motion platform for semiconductors according to claim 1, characterized in that, The controller (13) is an EtherCAT master station for Ethernet control automation technology. The controller (13) is connected to multiple drivers through the Ethernet control automation technology bus.

9. The high-precision mechanical guide linear motion platform for semiconductors according to claim 6, characterized in that, The subdivision box output is connected to the controller (13) and is used to process the raw position information of the reading head and provide a position feedback signal to the controller (13).

10. The high-precision mechanical guide linear motion platform for semiconductors according to claim 7, characterized in that, At least one of the multiple drivers is a dual-channel driver, and the two channels of the dual-channel driver synchronously control the two linear motors in the X linear motor (2). The multiple reading heads and multiple subdivision boxes include two sets corresponding to the two linear motors in the X linear motor (2) respectively, and provide independent feedback signals to the controller (13).

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