CN105487345A - Electric-refrigeration-chip-based dynamic-magnetic-steel magnetic levitation dual-stage vector arc switching method and device - Google Patents

Abstract

The moving magnet steel magnetic levitation double workpiece table vector circular arc transfer method and device based on electric refrigeration sheets belong to the semiconductor manufacturing equipment technology, and the device includes a support frame, a balance mass, a magnetic levitation workpiece table, a workpiece table measuring device, and a workpiece table driving device , the two workpiece tables work between the measurement position and the exposure position, the interferometer is used to measure the position of the workpiece table, and the passive compensation structure composed of planar leaf spring and electromagnetic damper is used to compensate the movement of the balance mass. The moving magnet steel type magnetic levitation planar motor driven by the electric cooling plate structure, in the process of double workpiece table exchange, the planar motor is used to drive the two workpiece tables to realize the single-beat arc rapid table change; , Long trajectory, many start-stop links, long stabilization time and other problems, reduce the number of steps to change the stage, shorten the time for changing the stage, and improve the productivity of the lithography machine.

Description

Method and device for moving magnetic steel maglev double workpiece table vector arc exchange table based on electric refrigeration sheet

technical field

The invention belongs to the technical field of semiconductor manufacturing equipment, and mainly relates to a method and a device for a moving magnetic steel magnetic levitation double workpiece table vector arc return conversion table based on an electric refrigeration plate.

Background technique

Lithography machine is one of the important ultra-precision equipment in the manufacture of very large scale integrated circuits. As the key subsystem of the lithography machine, the workpiece table largely determines the resolution, overlay accuracy and productivity of the lithography machine.

Productivity is one of the main goals of lithography machine development. Under the condition of satisfying the resolution and overlay accuracy, improving the operating efficiency of the workpiece table and thus improving the productivity of the lithography machine is the development direction of the workpiece table technology. The most direct way to improve the operating efficiency of the workpiece table is to increase the motion acceleration and speed of the workpiece table, but in order to ensure the original accuracy, the speed and acceleration cannot be increased without limit. The initial workpiece table only had one silicon wafer carrier, and the lithography machine could only process one silicon wafer at a time. All processes were processed serially, and the production efficiency was low. For this reason, someone has proposed a double worktable technology, which is also the mainstream technical means to improve the production efficiency of lithography machines. The double worktable technology has two work stations for exposure and pretreatment and two workbenches on the workbench. The exposure and measurement adjustment can be processed in parallel, which greatly shortens the time and improves the production efficiency. The current representative product is the lithography machine based on the Twinscan technology, that is, the double-workpiece technology of ASML company in the Netherlands.

Improving the operating efficiency of the double workpiece table is one of the development goals of the current lithography machine workpiece table technology. The double workpiece table technology involves the problem of switching the workpiece table between two stations, and the efficiency of table switching directly affects the operating efficiency of the workpiece table of the lithography machine, that is, the productivity of the lithography machine. How to reduce the interference of channel switching to other systems while shortening the channel switching time as much as possible has always been the focus of research. In the traditional double-table switching process, the workpiece table is linearly driven in the exposure and pretreatment processes. In the dual-stage patents US2001/0004105A1 and W098/40791, each workpiece table has two interchangeable and coordinated units to achieve double-stage The exchange of the workpiece table improves the productivity without increasing the movement speed of the workpiece table. However, due to the coupling connection between the workpiece table and the guide rail, the workpiece table and the drive unit will be separated temporarily during the table change process, which will affect the workpiece table. The positioning accuracy has a great influence. At the same time, the motion unit and guide rail are longer, and the motion mass is larger, which has adverse effects on the improvement of motion speed and acceleration. Chinese patent CN101609265 proposes a planar motor-driven multiple exchange system for wafer stages. The stator of the planar motor is arranged on the top of the base stage, and the mover is arranged at the bottom of the wafer stage. Compared with the linear motor drive, there is no separation between the workpiece stage and the drive unit. Separation; Chinese patent CN101694560 proposes a dual-table exchange system driven by an air-supported permanent magnet planar motor. The workpiece table is driven by a planar motor and supported by air flotation, which avoids the separation of the drive unit and the workpiece table during the aforementioned table-changing process The problem is that the running resistance of the workpiece table is reduced, the driving current of the planar motor is reduced, and the problem of heat dissipation is reduced.

The above-mentioned patent adopts a straight-line table-changing scheme when changing tables, and the back-turning table-changing scheme has unique advantages over the straight-line table-changing scheme, so a double-workpiece table technology using a back-turning table appears. Chinese patent CN101071275 adopts the method of rotating the whole abutment to realize the transposition of the double workpiece table, which simplifies the system structure, and at the same time, the movement of the two workpiece tables has no overlapping area, avoiding the potential safety hazard of collision. However, there are problems such as large moment of inertia, difficulty in precise positioning of high-power rotary motors, and high heat generation that cause system temperature rise by rotating the entire base to achieve workpiece table transposition. At the same time, the radius of rotation is large, which significantly increases the main structure of the lithography machine. Chinese patent CN102495528 adopts a rotary transfer table in the center of the abutment to complete the exchange of double workpiece tables. The table change is divided into three beats, which improves the efficiency of the table change. However, the structure of the rotary transfer table is complicated and the rotary positioning accuracy is low.

Contents of the invention

Aiming at the deficiencies of the above-mentioned prior art, the present invention proposes a method and device for a moving magnetic steel maglev double workpiece table vector arc return conversion table based on an electric refrigeration plate, so as to achieve single-beat rapid arc change of the workpiece table and reduce The purpose of changing the stage, shortening the stage changing time, and effectively improving the productivity of the lithography machine.

The purpose of the present invention is achieved like this:

A method for moving magnetic steel maglev double workpiece stage vector arc transfer method based on electric refrigeration sheet, the method includes the following steps: initial working state, the first workpiece stage at the measurement position is in a pre-aligned state, and the second workpiece stage at the exposure position In the exposure state; in the first step, after the pre-alignment of the first workpiece table at the measurement position is completed, it is driven by the moving magnet to move to the predetermined position A of the measurement position for changing the table, charging and waiting, and the second workpiece table at the exposure position is exposed by the moving magnet The steel drive moves to the predetermined position C of the exposure position; in the second step, the first workpiece table and the second workpiece table move counterclockwise along the circular arc track through the vector control of the plane motor, and the phase of the two workpiece tables does not change during the movement , the movement position is measured by the interferometer, when the first workpiece table is driven by the moving magnet to move to the predetermined position C of the exposure position, and the second workpiece table is driven by the moving magnet to move to the predetermined position D of the measurement position, the stage change is completed, and the second One workpiece stage performs silicon wafer lithography exposure at the exposure position, and the second workpiece stage performs silicon wafer loading and silicon wafer pre-alignment operations at the measurement position; in the third step, after the pre-alignment of the second workpiece stage at the measurement position is completed, the dynamic The magnetic steel drive moves to the predetermined position A' of the measurement position and changes the stage, and charges and waits. After the exposure of the first work table at the exposure position, it is driven by the moving magnetic steel to move to the predetermined position C of the exposure position; the fourth step, the second work table and the first work table A workpiece table moves clockwise along the circular arc track through the vector control of the plane motor. When the second workpiece table is driven by the moving magnet to move to the predetermined position C of the exposure position, and the first workpiece table is driven by the moving magnet to move to the predetermined position of the measurement position D When the stage change is over, the second workpiece stage at the exposure position enters the exposure state, and the first workpiece stage at the measurement position performs loading and unloading and pre-alignment operations. The working cycle is completed by wireless communication in the process of measurement, exposure and channel change.

A moving magnetic steel magnetic levitation double workpiece platform vector circular arc platform changing device based on an electric refrigeration sheet, the device includes a support frame, a balance mass, a first workpiece platform, a second workpiece platform, and a wireless charging transmitter. The mass block is located above the support frame, the macro-moving planar motor stator is installed on the plane on the balance mass block, the first workpiece platform and the second workpiece platform are arranged above the macro-moving planar motor stator, and the first workpiece platform and the second workpiece The stage runs between the measurement position and the exposure position, and 6 interferometers are installed on the support frame; the support frame is connected with the balance weight through a motion compensation mechanism composed of a planar leaf spring and an electromagnetic damper in parallel. It consists of 1 pair of X-direction leaf springs, 1 pair of Y-direction leaf springs, 1 Z-direction leaf spring and 1 Rz flexible hinge. The electromagnetic damper consists of the upper back plate of the damper, the upper Y-direction permanent magnet array and the X-direction The permanent magnet array, the copper plate, the lower Y-direction permanent magnet array, the X-direction permanent magnet array, and the lower back plate of the damper are assembled. The array is installed between the upper back plate of the damper and the copper plate, the lower Y and X direction permanent magnet arrays are installed between the copper plate and the lower back plate of the damper, and form a strong magnetic field in the air gap, and the copper plate is fixed on the support frame On the top, the upper back plate of the damper is fixed with the balance mass block, which can produce X, Y translation and Rz rotation relative to the upper and lower back plate copper plates; the first workpiece table and the second workpiece table are six-degree-of-freedom maglev micro-motion tables , the six-degree-of-freedom maglev micro-motion table is composed of Chuck, suction cup, pyramid edge, anti-collision frame, macro-motion planar motor mover, zero sensor, leveling and focusing sensor, electric cooling chip, wireless charging receiver, wireless Composed of a communication transceiver, the micro-motor is composed of a micro-motion planar motor mover and a gravity compensator mover. The suction cup is installed on the Chuck, and four corners are installed around the Chuck. The anti-collision frame, the mover of the macro planar motor is installed under the anti-collision frame, the mover of the macro planar motor is composed of a staggered arrangement of magnetic steel arrays, and the stator of the macro planar motor is composed of a coil array arranged in a herringbone shape.

The present invention has the following innovations and outstanding advantages:

1) Propose the arc vector channel changing method, and design the arc vector channel changing device. The vector table change strategy is used to optimize the existing multi-beat linear table change of the double workpiece table into a single-beat fast table change, with fewer starts and stops and fewer stable links; at the same time, the arc trajectory planning is used to shorten the table change path, and the rotary impact is small , The stabilization time is short, and the real-time measurement system monitors the exchange process to ensure the macro/micro positioning accuracy during the channel change process, directly traceable to the laser wavelength, and finally realizes the high efficiency and high precision of the channel change. This is one of the innovation points and outstanding advantages of the present invention;

2) A work table exchange method without cable interference of wireless power supply and wireless communication is proposed, and a double work table device for wireless power supply and wireless communication is designed. Based on the maglev magnetic drive, the device adopts wireless power supply and wireless signal transmission methods to realize the wireless transmission and control of the power supply and communication signals of the two micro-tables, making the overall structure compact, and more importantly, eliminating the need for cables and signal lines The impact of cable disturbance on the positioning accuracy of the double worktable realizes wireless power supply, wireless communication data transmission and no cable constraints. This is the second of innovation and outstanding advantages of the present invention;

3) A large-stroke magnetic drive method for a moving magnet steel maglev planar motor with an electric cooling plate structure is proposed, and a moving magnet steel maglev planar motor device with an electric cooling plate structure is designed. The device adopts compound current drive to realize high-efficiency vector control. It has a large range of motion, high thrust density, good dynamic characteristics, and high utilization of windings. Advantages such as small, this is innovation point of the present invention and outstanding advantage three;

4) Propose a passive compensation method and an impulse balance method, and design a passive compensation and balance mass mechanism based on an electromagnetic damper and a planar leaf spring. This mechanism can realize the X-direction, Y-direction, Z-direction and Rz motion compensation of the balance mass. Compared with the active compensation structure, it reduces the complexity of the mechanism and reduces the difficulty of control and implementation. This is the innovation and highlight of the present invention. The fourth advantage.

Description of drawings

Fig. 1 is a schematic diagram of a single-beat optimized planning arc fast channel change process.

Fig. 2 is a schematic diagram of the overall structure of the moving magnet steel maglev double workpiece table vector arc table changing device based on the electric refrigeration plate.

Fig. 3 is a schematic diagram of the assembly structure of the motion compensation mechanism and the balance mass.

Fig. 4 is a schematic diagram of the planar leaf spring structure.

Fig. 5 is a schematic diagram of the electromagnetic damping structure.

Fig. 6 is a schematic diagram of the magnetic steel arrangement of the electromagnetic damper.

Fig. 7 is a schematic structural diagram of a six-degree-of-freedom maglev micro-motion stage.

Fig. 8 is a schematic diagram of the integration mechanism of the micro-motion planar motor mover and the gravity compensator.

Fig. 9 is a schematic diagram of the arrangement of the magnetic rigid array of the mover of the macro-moving planar motor.

Fig. 10 is a schematic diagram of the array arrangement of the stator coils of the macro-motion planar motor.

Part number in the picture: 1-supporting frame; 2-balance mass system; 3-macro planar motor stator; 4a-first workpiece table; 4b-second workpiece table; 5-interferometer; 10-support frame; 11- Measuring position; 12-exposure position; 13-parallel leaf spring; 14-electromagnetic damper; 21-upper back plate of damper; 22a-upper Y-direction permanent magnet array; 22b-upper X-direction permanent magnet array; 23-copper plate ; 24a-lower Y-direction permanent magnet array; 24b-lower X-direction permanent magnet array; 25-damper lower back plate; 26-X-direction leaf spring; 27-Y-direction leaf spring; Rz flexible hinge; 401-Chuck; 402-suction cup; 403-corner cube; 404-anti-collision frame; 405-macro planar motor mover; 406-zero sensor; 409-gravity compensator mover; 410-electric cooling sheet; 411-magnetic steel array; 412-coil array; 413-wireless charging receiver; 414-wireless communication transceiver.

detailed description

Below in conjunction with accompanying drawing, embodiment of the present invention is described in further detail:

A method for moving magnetic steel maglev double workpiece stage vector arc transfer method based on electric refrigeration sheet, the method includes the following steps: initial working state, the first workpiece stage at the measurement position is in a pre-aligned state, and the second workpiece stage at the exposure position In the exposure state; in the first step, after the pre-alignment of the first workpiece table at the measurement position is completed, it is driven by the moving magnet to move to the predetermined position A of the measurement position for changing the table, charging and waiting, and the second workpiece table at the exposure position is exposed by the moving magnet The steel drive moves to the predetermined position C of the exposure position; in the second step, the first workpiece table and the second workpiece table move counterclockwise along the circular arc track through the vector control of the plane motor, and the phase of the two workpiece tables does not change during the movement , the movement position is measured by the interferometer, when the first workpiece table is driven by the moving magnet to move to the predetermined position C of the exposure position, and the second workpiece table is driven by the moving magnet to move to the predetermined position D of the measurement position, the stage change is completed, and the second One workpiece stage performs silicon wafer lithography exposure at the exposure position, and the second workpiece stage performs silicon wafer loading and silicon wafer pre-alignment operations at the measurement position; in the third step, after the pre-alignment of the second workpiece stage at the measurement position is completed, the dynamic The magnetic steel drive moves to the predetermined position A' of the measurement position and changes the stage, and charges and waits. After the exposure of the first work table at the exposure position, it is driven by the moving magnetic steel to move to the predetermined position C of the exposure position; the fourth step, the second work table and the first work table A workpiece table moves clockwise along the circular arc track through the vector control of the plane motor. When the second workpiece table is driven by the moving magnet to move to the predetermined position C of the exposure position, and the first workpiece table is driven by the moving magnet to move to the predetermined position of the measurement position D When the stage change is over, the second workpiece stage at the exposure position enters the exposure state, and the first workpiece stage at the measurement position performs loading and unloading and pre-alignment operations. The working cycle is completed by wireless communication in the process of measurement, exposure and channel change.

A moving magnetic steel magnetic levitation double workpiece table vector arc transfer device based on an electric refrigeration plate, the device includes a support frame 1, a balance mass 2, a first workpiece table 4a, a second workpiece table 4b, and a wireless charging transmitter 30, the balance mass 2 is located above the support frame 1, the macro-motion planar motor stator 3 is installed on the plane of the balance mass 2, and the first work table 4a and the second work table 4b are arranged on the macro-motion planar motor stator 3 Above, the first workpiece table 4a and the second workpiece table 4b run between the measurement position 11 and the exposure position 12, and 6 interferometers are installed on the support frame 10; the support frame 1 passes through the planar leaf spring 13 and electromagnetic damping The motion compensating mechanism composed of parallel devices 14 is connected with the balance mass 2, and the planar leaf spring 13 consists of a pair of X-direction leaf springs 26, a pair of Y-direction leaf springs 27, a Z-direction leaf spring 28 and a Rz The electromagnetic damper 14 is composed of a damper upper back plate 21, an upper Y-direction permanent magnet array 22a and an X-direction permanent magnet array 22b, a copper plate 23, a lower Y-direction permanent magnet array 24a and an X-direction permanent magnet The array 24b and the damper lower backplane 25 are assembled, the damper upper backplane 21 and the damper lower backplane 25 are fixed, and the upper Y and X direction permanent magnet arrays 22a and 22b are installed on the damper upper backplane 21 and the purple Between the copper plates 23, the lower Y and X direction permanent magnet arrays 24a, 24b are installed between the copper plate 23 and the lower back plate 25 of the damper, and form a strong magnetic field between the air gaps, and the copper plate 23 is fixed on the supporting frame 1, The upper back plate 21 of the damper is fixed to the balance mass 2, and the red copper plate 23 can produce X, Y direction translation and Rz rotation relative to the upper and lower back plates 21, 25; the first workpiece table 4a and the second workpiece table 4b are six Degree of freedom maglev micro-motion stage, the six-degree-of-freedom maglev micro-motion stage consists of Chuck401, suction cup 402, corner cone 403, anti-collision frame 404, macro-motion planar motor mover 405, zero sensor 406, leveling and focusing sensor 407, an electric cooling plate 410, a wireless charging receiver 413, and a wireless communication transceiver 414. The micro-motion motor 403 is composed of a micro-motion planar motor mover 408 and a gravity compensator mover 409. The suction cup 402 Installed on Chuck401, Chuck401 is surrounded by four pyramidal corners 403, Chuck401 is surrounded by anti-collision frame 404, the macro-motion planar motor mover 405 is installed under the anti-collision frame 404, the macro-motion planar motor mover 405 is composed of The magnetic steel array 411 is arranged in a staggered manner, and the stator 3 of the macro-motion planar motor is formed by a coil array 412 arranged in a herringbone shape.

The working process of the present invention is as follows:

After the pre-alignment of the measurement position 11, the first workpiece table 4a is driven by the plane motor to move to the stage change position A, and waits for the second workpiece table 4b to complete the exposure at the exposure position 12. After the second workpiece table 4b completes the exposure, it is driven by the plane motor Drive and move to the stage change position B, and then the first workpiece table 4a and the second workpiece table 4b move counterclockwise along the circular arc track through the plane motor vector control to complete the stage change operation; after the stage change is completed, the first workpiece table 4a moves to the exposure position 12 moves to perform exposure at exposure position 12, and the second workpiece table 4b moves to measurement position 11 to perform loading and pre-alignment operations at measurement position 11; the second work table 4b that has completed pre-alignment of the silicon wafer first moves to the measurement position Change the stage position A', wait for the first workpiece stage 4a to complete the exposure and then move to the stage change position B', then, the second workpiece stage 4b and the first workpiece stage 4a move clockwise along the circular arc track through the vector control of the plane motor, and complete The second stage change; after the stage change is completed, the first workpiece stage 4a moves to the measurement position 11, and the second workpiece stage 4b moves to the exposure position 12, thus completing a complete working cycle.

Claims (2)

1. A method for moving magnetic steel maglev double workpiece table vector arc exchange based on electric refrigeration sheet, characterized in that the method comprises the following steps: initial working state, the first workpiece table at the measurement position is in a pre-aligned state, exposure The second workpiece stage at the position of exposure is in the exposure state; the first step, after the pre-alignment of the first workpiece stage at the measurement position, is driven by the moving magnet to move to the predetermined position A of the measurement position and change the stage, charging and waiting, and the second workpiece stage at the exposure position is exposed After the completion, it is driven by the moving magnet to move to the predetermined position C of the exposure position; in the second step, the first workpiece table and the second workpiece table move counterclockwise along the circular arc track through the vector control of the plane motor. During the movement, the two workpiece tables The phase of the phase does not change, and the moving position is measured by the interferometer. When the first workpiece table is driven by the moving magnet to move to the predetermined position C of the exposure position, and the second workpiece table is driven by the moving magnet to move to the predetermined position of the measurement position D, After the station change, the first worktable performs silicon wafer photolithography exposure at the exposure position, and the second worktable performs silicon wafer loading and silicon wafer pre-alignment operations at the measurement position; the third step, the second workbench pre-aligns at the measurement position After the calibration is completed, it is driven by the moving magnetic steel to move to the predetermined position A' of the measuring position and the platform is charged and waited for. The second workpiece table and the first workpiece table move clockwise along the circular arc track through the vector control of the plane motor. When the second workpiece table is driven by the moving magnetic steel to the predetermined position C of the exposure position, the first workpiece table is driven by the moving magnetic steel to move to When the measurement position is at the predetermined position D, the stage change is completed, the second workpiece stage at the exposure position enters the exposure state, and the first workpiece stage at the measurement position performs loading and unloading and pre-alignment operations. At this time, the system returns to the initial working state and completes two A working cycle of channel changing operation is completed by wireless communication in the process of measurement, exposure and channel changing. 2. A moving magnetic steel magnetic levitation double workpiece table vector arc transfer device based on an electric refrigeration plate, characterized in that the device includes a support frame (1), a balance mass (2), and a first workpiece table (4a) , a second workpiece table (4b), a wireless charging transmitter (30), the balance mass (2) is located above the support frame (1), and the macro-motion planar motor stator (3) is installed on the balance mass (2) On the plane, the first workpiece table (4a) and the second workpiece table (4b) are arranged above the macro-motion planar motor stator (3), and the first workpiece table (4a) and the second workpiece table (4b) run on Between the measurement position (11) and the exposure position (12), 6 interferometers are installed on the support frame (10); The motion compensation mechanism is connected with the balance mass (2), and the planar leaf spring (13) consists of a pair of X-direction leaf springs (26), a pair of Y-direction leaf springs (27), and a Z-direction leaf spring (28 ) and one Rz flexible hinge (29), the electromagnetic damper (14) consists of the damper upper back plate (21), upper Y-direction permanent magnet array (22a) and X-direction permanent magnet array (22b), purple The copper plate (23), the lower Y-direction permanent magnet array (24a), the X-direction permanent magnet array (24b), the damper lower backplane (25) are assembled, the damper upper backplane (21) and the damper lower backplane (25) Fixing, wherein the upper Y and X direction permanent magnet arrays (22a, 22b) are installed between the upper back plate (21) and the copper plate (23) of the damper, and the lower Y and X direction permanent magnet arrays (24a, 24b ) is installed between the red copper plate (23) and the lower back plate of the damper (25), and forms a strong magnetic field in the air gap, the red copper plate (23) is fixed on the support frame (1), and the upper back plate of the damper (21 ) is fixed with the balance mass block (2), relative to the upper and lower back plates (21, 25) the copper plate (23) can produce X, Y direction translation and Rz rotation; the first workpiece table (4a) and the second workpiece table (4b) is a six-degree-of-freedom maglev micro-motion stage, which consists of Chuck (401), suction cup (402), pyramid edge (403), anti-collision frame (404), macro-motion plane motor Composed of motor (405), zero sensor (406), leveling and focusing sensor (407), electric cooling plate (410), wireless charging receiver (413), wireless communication transceiver (414), the micro-movement The motor (403) is composed of a micro-motion planar motor mover (408) and a gravity compensator mover (409). The suction cup (402) is installed on the Chuck (401), and Chuck (401) is surrounded by four A pyramid edge (403), Chuck (401) is surrounded by an anti-collision frame (404), the macro-motion planar motor mover (405) is installed under the anti-collision frame (404), and the macro-motion planar motor mover ( 405) consists of a staggered arrangement of magnetic steel arrays (411), and the macro-moving planar motor stator (3) is composed of coils The array (412) is arranged in a herringbone shape.