CN104049472B - A kind of electromagnetic launch starts formula reticle stage system - Google Patents
A kind of electromagnetic launch starts formula reticle stage system Download PDFInfo
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- CN104049472B CN104049472B CN201410306905.1A CN201410306905A CN104049472B CN 104049472 B CN104049472 B CN 104049472B CN 201410306905 A CN201410306905 A CN 201410306905A CN 104049472 B CN104049472 B CN 104049472B
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/20—Exposure; Apparatus therefor
Abstract
A kind of electromagnetic launch starts formula reticle stage system, and in Optical Coatings for Photolithography, described reticle stage system comprises base, counterbalance weight assembly, mask platform move platform and measuring system.Described counterbalance weight assembly comprises counterbalance weight, mask platform YZ to motor coil and mask platform X to motor coil; Described mask platform moves that platform comprises that mask platform is moved at the bottom of stylobate, mask platform YZ is to magnetic steel of motor array and mask platform X to magnetic steel of motor array; Described electromagnetic launch starts formula reticle stage system and also comprises ejection structure, and described ejection structure comprises ejection structure magnetic steel of stator array, ejection structure mover magnetic steel array, launches platform, launches platform electric mover, launches platform motor stator and guide rail.The present invention adopts ejection structure, improves the startup of mask aligner mask platform and the acceleration of stop phase, reduces the acceleration time, reduces energy consumption and the requirement to driver.
Description
Technical field
The present invention relates to a kind of electromagnetic launch and start formula reticle stage system, this reticle stage system is applied in semiconductor lithography machine, belongs to semiconductor manufacturing equipment technical field.
Background technology
The workpiece table system of litho machine is divided into mask platform and silicon wafer stage two subsystems, for carrying out the exposure of a chip on silicon chip, mask platform and silicon wafer stage need to carry out accelerated motion respectively, and reach the speed of the 4:1 required by scan exposure when moving to exposure reference position simultaneously.After this, silicon wafer stage is with uniform speed to the motion of scanning motion direction, and mask platform does scanning motion with 4 times of speed to silicon wafer stage sweep velocity to the opposite direction with silicon wafer stage scanning motion, and both movement needs reach synchronously split hair.Whole pattern imagings the most at last on mask are in the certain chip (chip) of silicon chip.When after a chip end of scan, mask platform and silicon wafer stage carry out retarded motion respectively, and silicon wafer stage carries out step motion simultaneously, is moved to below projection objective by the chip that the next one will expose.After this, mask platform is accelerated to the direction contrary with last scan direction of motion, scan, slow down, and silicon wafer stage then accelerates according to the direction of planning, scanning, slow down, and completes the exposure of a chip in synchronous scanning process.So constantly repeat, mask platform comes and goes the rectilinear motion carrying out accelerating, scanning, slow down, and silicon wafer stage carries out stepping and scanning motion according to the track of planning, completes the exposure of whole silicon chip.According to the movement needs to mask platform, mask platform mainly provides the function coming and going ultraprecise high-speed straight-line along direction of scanning and move, and its stroke should meet 4 times of chip length and add the distance of acceleration and deceleration; Its sweep velocity should be 4 times of silicon wafer stage sweep velocity, and most high acceleration also accordingly can higher than the most high acceleration of silicon wafer stage.
Mask platform is provided by drive motor usually at the acceleration of accelerating and decelerating part, and each accelerating and decelerating part motor all needs work, and this Starting mode is long for start-up time, and efficiency is low, there is larger energy consumption.Along with the development of semiconductor fabrication, the following acceleration to mask platform requires can be higher, and the driver of drive motor can be caused to be difficult to meet.Patent documentation 201110008388.6 arranges motion permanent magnetic body and two stationary parts be fixed in litho machine frame respectively at mask platform two ends, stationary part can be electromagnet or permanent magnet, motion permanent magnetic body and stationary part composition vibrating device, increase the acceleration of mask platform by the repulsion between motion permanent magnetic body and stationary part.When stationary part is permanent magnet, the acceleration provided is inadequate, needs reciprocal acceleration just can reach required acceleration; When stationary part is electromagnet, electromagnet all needs energising at each accelerating and decelerating part, additionally can increase energy consumption; When stationary part is the combination of permanent magnet and electromagnet, start-up course is complicated, and start-up time is long, so its mask platform starts and the performance of stopped process is restricted.
Summary of the invention
In order to the acceleration of the startup and stop phase that improve mask aligner mask platform, reduce Acceleration and deceleration time, improve litho machine productive rate, reduce energy consumption, the invention provides a kind of electromagnetic launch and start formula reticle stage system.
Technical scheme of the present invention is as follows:
A kind of electromagnetic launch starts formula reticle stage system, described reticle stage system comprises base, counterbalance weight assembly, mask platform move platform and measuring system, described counterbalance weight assembly comprises counterbalance weight, mask platform YZ to motor coil and mask platform X to motor coil, is provided with vibrating isolation system between counterbalance weight and base, described mask platform is moved platform and is comprised mask platform and move at the bottom of stylobate, mask platform YZ is to magnetic steel of motor array and mask platform X to magnetic steel of motor array, mask platform YZ is arranged on mask platform to magnetic steel of motor array and moves lower surface at the bottom of stylobate, mask platform X to magnetic steel of motor array be arranged on mask platform move at the bottom of stylobate perpendicular on two sides of X-direction, it is characterized in that: described electromagnetic launch starts formula reticle stage system and also comprises ejection structure, described ejection structure comprises ejection structure magnetic steel of stator array, ejection structure mover magnetic steel array, launch platform, launch platform electric mover, launch platform motor stator and guide rail, launch platform motor stator and guide rail is fixed on counterbalance weight, launch platform electric mover and be fixed on the bottom of launching platform, described ejection structure magnetic steel of stator array comprises the first ejection structure magnetic steel of stator array and the second ejection structure magnetic steel of stator array, first ejection structure magnetic steel of stator array is contained in and launches platform and move on side relative at the bottom of stylobate with mask platform, second ejection structure magnetic steel of stator array is contained on counterbalance weight, and relative with the first ejection structure magnetic steel of stator array, move at the bottom of stylobate in mask platform and arrange described ejection structure mover magnetic steel array respectively perpendicular to two of Y-direction sides, and be mounted opposite respectively with the first ejection structure magnetic steel of stator array and the second ejection structure magnetic steel of stator array.
Vibrating isolation system between counterbalance weight and base adopts air supporting vibrating isolation system or magnetic to float vibrating isolation system.Described mask platform YZ adopts halbach array to magnetic steel of motor array.Described measuring system adopts laser interferometer and capacitive transducer to realize the measurement of six degree of freedom.
Electromagnetic launch of the present invention starts formula reticle stage system and has the following advantages and high-lighting effect: the present invention adopts electromagnetic launch to carry out starting and stopping, improve the startup of mask aligner mask platform and the acceleration of stop phase, reduce the acceleration time, reduce the requirement of the driver to mask platform drive motor, and adopt permanent magnet in ejection structure, reduce energy consumption.
Accompanying drawing explanation
Fig. 1 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system original state.
Fig. 2 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts that formula reticle stage system mask platform moves platform.
Fig. 3 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system ejection structure.
Fig. 4 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system working stage.
In figure: 1-base; 2-counterbalance weight; 3-first ejection structure magnetic steel of stator array; 4-ejection structure mover magnetic steel array; 5-mask platform YZ is to motor coil; 6-mask platform X is to motor coil; 7-second ejection structure magnetic steel of stator array; 8-launches platform; 9-launches platform electric mover; 10-launches platform motor stator; 11-guide rail; 12-mask platform is moved at the bottom of stylobate; 13-mask platform YZ is to magnetic steel of motor array; 14-mask platform X is to magnetic steel of motor array; 15-X is to catoptron; 16-Y is to catoptron; 17-one-axis laser interferometer; 18-tri-axle laser interferometer.
Embodiment
Below in conjunction with accompanying drawing, concrete structure of the present invention, mechanism and the course of work are further described.
Fig. 1 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system original state, and a kind of electromagnetic launch provided by the invention starts that formula reticle stage system comprises base 1, counterbalance weight assembly, mask platform move platform, measuring system and ejection structure; Described counterbalance weight assembly comprises counterbalance weight 2, mask platform YZ to motor coil 5 and mask platform X to motor coil 6, wherein adopts air supporting vibrating isolation system or magnetic to float vibrating isolation system supporting between counterbalance weight and base.Mask platform YZ is the coil arrays of arranging along Y-direction at the upper surface of counterbalance weight to motor coil 5, and guide rail 11 is installed along Y-direction; Mask platform YZ is used to provide mask platform to motor and moves the buoyancy of platform Z-direction and the driving force of Y-direction.Mask platform X is arranged on the outside of mask platform YZ to motor coil 5 to motor coil 6, and mask platform X is used to provide to motor the driving force that mask platform moves platform X-direction.In Fig. 1, mask platform is moved platform and is in dynamic platform initial position, launches platform 8 and is in and launches platform initial position.Described measuring system adopts the capacitive transducer of one-axis laser interferometer 17, three axle laser interferometer 18 and two Z-directions to realize.Two X are arranged on to catoptron 15 upper surface that mask platform moves at the bottom of stylobate 12, are arranged symmetrically with along Y-direction, and wherein the X of side is arranged to catoptron 15 to make weight symmetrical.Y-direction catoptron 16 be arranged on mask platform to move at the bottom of stylobate 12 perpendicular to Y-direction and near the side of three axle laser interferometer 18.One-axis laser interferometer 17 arrange in X direction and and X to catoptron 15 coordinate be used for measurement X to displacement, three axle laser interferometer along Y-direction arrange and and Y-direction catoptron 16 be used for measuring Y-direction displacement, corner around X-direction and Z-direction, the displacement of Z-direction and the corner of Y-direction adopt 2 capacitive transducers along Z-direction layout to measure.
Fig. 2 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts that formula reticle stage system mask platform moves platform.Mask platform moves that platform comprises that mask platform to move at the bottom of stylobate 12, mask platform YZ is to magnetic steel of motor array 13, mask platform X to magnetic steel of motor array 14; Mask platform YZ is halbach array to magnetic steel of motor array, comprise two groups and symmetrical be arranged on the lower surface that mask platform moves at the bottom of stylobate 12, relative to motor coil 5 with mask platform YZ respectively along Y-direction arrangement; Mask platform X is arranged on mask platform to magnetic steel of motor array 14 and moves at the bottom of stylobate 12 perpendicular to two sides of X-direction, and relative to motor coil 6 with mask platform X.
Fig. 3 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system ejection structure.Described ejection structure comprises ejection structure magnetic steel of stator array, ejection structure mover magnetic steel array 4, launches platform 8, launches platform electric mover 9, launches platform motor stator 10 and guide rail 11; Launch platform motor stator 10 and guide rail 11 is fixed on counterbalance weight 2, launch platform electric mover 9 and be fixed on the bottom of launching platform 8; Described ejection structure magnetic steel of stator array comprises the first ejection structure magnetic steel of stator array 3 and the second ejection structure magnetic steel of stator array 7, in the present embodiment, first ejection structure magnetic steel of stator array 3 comprises two groups, be arranged on and launch platform 8 and mask platform and to move at the bottom of stylobate on 12 relative sides, and be arranged symmetrically with, second ejection structure magnetic steel of stator array 7 comprises two groups, is arranged on counterbalance weight 2, and respectively with the first ejection structure magnetic steel of stator array 3 is relative; To move at the bottom of stylobate in 12 in mask platform and arrange described ejection structure mover magnetic steel array 4 respectively perpendicular to two sides of Y-direction, each Side symmetrical arranges two groups, and is mounted opposite with the first ejection structure magnetic steel of stator array 3 and the second ejection structure magnetic steel of stator array 7 and there is repulsion effect with magnetic steel of stator array respectively.
A kind of electromagnetic launch provided by the invention starts the formula reticle stage system course of work be divided into unloading phase, working stage and stop phase.Unloading phase, as shown in Figure 1, mask platform is moved before platform starts and is still in dynamic platform initial position, launching under the effect of platform motor, launch platform and move platform motion from launching platform initial position to mask platform, move the ejection structure mover magnetic steel array 4 on platform due to mask platform and launch the repulsion between the first ejection structure magnetic steel of stator array 3 on platform, mask platform is moved platform and is ejected with a very large acceleration, make mask platform move platform and directly reach normal operating rate, thus enter working stage; Fig. 4 is the schematic diagram that a kind of electromagnetic launch provided by the invention starts formula reticle stage system working stage.As shown in Figure 4, at working stage, launch platform to stop at and launch platform working position, platform is moved to move to-the end of Y-direction stroke when mask platform, the distance that mask platform to be moved at the bottom of stylobate between ejection structure mover magnetic steel array on 12 and the second ejection structure magnetic steel of stator array 7 on counterbalance weight 2 is more and more less, repulsion is increasing, makes mask platform move platform speed and is kept to zero and oppositely accelerates, again reach normal operating rate; Platform is moved to move to+the end of Y-direction stroke when mask platform, mask platform to move at the bottom of stylobate the ejection structure mover magnetic steel array on 12 and the distance of launching between the first upper ejection structure magnetic steel of stator array 3 on platform 8 more and more less, repulsion is increasing, make mask platform move platform speed be kept to zero and oppositely accelerate, again reach normal operating rate.Mask platform YZ moves the speed of platform to mask platform and attitude is finely tuned to motor at working stage, meets the speed of system to it and the requirement of position, simultaneously the energy dissipation of bucking-out system.And so forth, mask platform is moved in platform one section of perform region in the Y direction and is moved reciprocatingly.At stop phase, mask platform is moved platform and is moved to mask platform initial position by mask platform perform region, and mask platform is moved platform and promoted to launch platform, repulsion between the two makes to launch platform and ejects, make mask platform move platform to slow down, and stop at mask platform initial position fast, reach quick stopping object.
Claims (4)
1. an electromagnetic launch starts formula reticle stage system, described reticle stage system comprises base (1), counterbalance weight assembly, mask platform move platform and measuring system, described counterbalance weight assembly comprises counterbalance weight (2), mask platform YZ to motor coil (5) and mask platform X to motor coil (6), is provided with vibrating isolation system between counterbalance weight (2) and base (1), described mask platform is moved platform and is comprised mask platform and move (12) at the bottom of stylobate, mask platform YZ is to magnetic steel of motor array (13) and mask platform X to magnetic steel of motor array (14), mask platform YZ is arranged on to magnetic steel of motor array (13) lower surface that mask platform moves (12) at the bottom of stylobate, mask platform X to magnetic steel of motor array (14) be arranged on mask platform move (12) at the bottom of stylobate perpendicular on two sides of X-direction, it is characterized in that: described electromagnetic launch starts formula reticle stage system and also comprises ejection structure, described ejection structure comprises ejection structure magnetic steel of stator array, ejection structure mover magnetic steel array (4), launch platform (8), launch platform electric mover (9), launch platform motor stator (10) and guide rail (11), launch platform motor stator (10) and guide rail (11) is fixed on counterbalance weight (2), launch platform electric mover (9) and be fixed on the bottom of launching platform (8), described ejection structure magnetic steel of stator array comprises the first ejection structure magnetic steel of stator array (3) and the second ejection structure magnetic steel of stator array (7), first ejection structure magnetic steel of stator array (3) is contained in and launches platform (8) and move on the side that at the bottom of stylobate, (12) are relative with mask platform, second ejection structure magnetic steel of stator array (7) is contained on counterbalance weight (2), and relative with the first ejection structure magnetic steel of stator array (3), move in (12) at the bottom of stylobate in mask platform and arrange described ejection structure mover magnetic steel array (4) respectively perpendicular to two of Y-direction sides, and be mounted opposite respectively with the first ejection structure magnetic steel of stator array (3) and the second ejection structure magnetic steel of stator array (7).
2. a kind of electromagnetic launch according to claim 1 starts formula reticle stage system, it is characterized in that: the vibrating isolation system between counterbalance weight (2) and base (1) adopts air supporting vibrating isolation system or magnetic to float vibrating isolation system.
3. a kind of electromagnetic launch according to claim 1 starts formula reticle stage system, it is characterized in that: described mask platform YZ adopts halbach array to magnetic steel of motor array (13).
4. a kind of electromagnetic launch according to claim 1 starts formula reticle stage system, it is characterized in that: described measuring system adopts laser interferometer and capacitive transducer to realize the measurement of six degree of freedom.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410306905.1A CN104049472B (en) | 2014-06-30 | 2014-06-30 | A kind of electromagnetic launch starts formula reticle stage system |
| PCT/CN2015/079238 WO2016000497A1 (en) | 2014-06-30 | 2015-05-19 | Electromagnetic ejection startup type mask table system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201410306905.1A CN104049472B (en) | 2014-06-30 | 2014-06-30 | A kind of electromagnetic launch starts formula reticle stage system |
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| CN104049472A CN104049472A (en) | 2014-09-17 |
| CN104049472B true CN104049472B (en) | 2016-03-30 |
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| CN104049472B (en) * | 2014-06-30 | 2016-03-30 | 清华大学 | A kind of electromagnetic launch starts formula reticle stage system |
| CN105301917B (en) * | 2015-11-19 | 2017-12-08 | 清华大学 | A kind of planing method for launching permanent magnetism mask platform shuttle-scanning movement locus |
| CN112436711B (en) * | 2020-11-12 | 2022-03-11 | 复旦大学 | Displacement device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102096338A (en) * | 2011-01-14 | 2011-06-15 | 清华大学 | Mask table system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPH1012538A (en) * | 1996-06-18 | 1998-01-16 | Canon Inc | Scanning stage unit and aligner using the same |
| JP3797670B2 (en) * | 2004-08-02 | 2006-07-19 | キヤノン株式会社 | Static pressure stage and scanning exposure apparatus |
| JP2007258356A (en) * | 2006-03-22 | 2007-10-04 | Canon Inc | Stage equipment |
| JP2008010643A (en) * | 2006-06-29 | 2008-01-17 | Canon Inc | Stage apparatus |
| JP5020597B2 (en) * | 2006-10-27 | 2012-09-05 | キヤノン株式会社 | Positioning apparatus, exposure apparatus, and device manufacturing method |
| CN103376665A (en) * | 2012-04-20 | 2013-10-30 | 上海微电子装备有限公司 | Masking platform horizontal measuring device and method |
| CN103186058B (en) * | 2013-02-06 | 2015-04-15 | 清华大学 | Mask platform system with six-degree-of-freedom coarse drive platform |
| CN104049472B (en) * | 2014-06-30 | 2016-03-30 | 清华大学 | A kind of electromagnetic launch starts formula reticle stage system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102096338A (en) * | 2011-01-14 | 2011-06-15 | 清华大学 | Mask table system |
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| CN104049472A (en) | 2014-09-17 |
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Address after: 100084 Beijing Haidian District 100084 box 82 box, Tsinghua University Patent Office Co-patentee after: U-PRECISION TECH CO., LTD. Patentee after: Tsinghua University Address before: 100084 Beijing Haidian District 100084 box 82 box, Tsinghua University Patent Office Co-patentee before: U-Precision Tech Co., Ltd. Patentee before: Tsinghua University |
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