WO2011072598A1

WO2011072598A1 - Dual-stage exchanging system for silicon wafer stage of lithography machine and exchange method thereof

Info

Publication number: WO2011072598A1
Application number: PCT/CN2010/079771
Authority: WO
Inventors: 朱煜; 张鸣; 徐登峰; 汪劲松; 董立立; 胡金春; 尹文生; 杨开明; 段广洪; 马竞; 张利
Original assignee: 清华大学
Priority date: 2009-12-15
Filing date: 2010-12-14
Publication date: 2011-06-23
Also published as: CN101727019A; CN101727019B

Abstract

A dual-stage exchanging system for the silicon wafer platform of the lithography machine includes two silicon wafer platforms (3, 8), a base platform (5), X-direction linear guide rails (2, 6), Y-direction linear guide rails (4,9), silicon wafer platform auxiliary drive units (11, 12) and four single-degree of freedom auxiliary drive units (1, 7, 15, 16). The system further comprises a first main drive unit (10) arranged on the first X-direction linear guide rail (2) and a second main drive unit (13) arranged on the second X-direction linear guide rail (6). Under the driving of the main drive units (10, 13), the Y-direction linear guide rails (4,9) can realize the movement along the X direction and the rotary motion in the plane of the base platform; when one of the Y-direction linear guide rails (4) drives the silicon wafer platform (3) to rotate to be parallel to the X direction, the other Y-direction linear guide rail (9) with the silicon wafer platform can realize translation motion in the X direction under the driving of the main drive unit (13), so as to exchange the positions of the two silicon wafer platforms (3, 8). A dual-stage exchange method for the silicon wafer of the lithography machine is also disclosed. The system avoids the defects of consistency of size of silicon wafer platforms and extremely high precision requirements of processing and assembling parts, not only simplifies system structure, but also improves the spatial utilization rate and precision of the system.

Description

Photolithography machine silicon wafer table double exchange system and exchange method thereof

The invention relates to a lithography machine silicon wafer table double exchange system and an exchange method thereof. The system is applied to a semiconductor lithography machine and belongs to the technical field of semiconductor manufacturing equipment.

In the production process of integrated circuit chips, the exposure design (lithography) of the chip design pattern on the photoresist on the surface of the silicon wafer is one of the most important processes. The device used in this process is called a photolithography machine. machine). The resolution and exposure efficiency of the lithography machine greatly affect the feature line width (resolution) and productivity of the integrated circuit chip. The motion precision and working efficiency of the silicon ultra-precision motion positioning system (hereinafter referred to as the silicon wafer system), which is the key system of the lithography machine, largely determine the resolution and exposure efficiency of the lithography machine.

The basic principle of the step-and-scan projection lithography machine is shown in Figure 1. The deep ultraviolet light from the light source 26 passes through a reticle 27 and a lens system 28 to image a portion of the pattern on the reticle on a particular chip of the silicon wafer 29. The reticle and the silicon wafer are reversely moved at a certain speed ratio, and finally all the patterns on the reticle are imaged on the chip of the silicon wafer.

The basic function of the wafer stage motion positioning system is to carry the silicon wafer during the exposure process and move at a set speed and direction to achieve accurate transfer of the mask pattern to various areas of the wafer. Since the line width of the chip is very small (the minimum line width has reached 45 nm at present), in order to ensure the engraving precision and resolution of the lithography, the wafer stage must have a very high motion positioning accuracy; in addition, the movement of the wafer stage Speed greatly affects the productivity of lithography, so it is necessary to continuously increase the speed of the wafer stage to increase productivity.

Traditional wafer stage, such as patent EP 0729073 and patent US As described in 5996437, there is only one wafer motion positioning unit in the lithography machine, that is, a silicon wafer stage. Preparations such as leveling and focusing are done on top of it. These tasks take a long time, especially alignment, due to the requirement for extremely high-speed low-speed scanning (typical alignment scan speed is 1). Mm/s), so it takes a long time. It is very difficult to reduce the working time. In order to improve the production efficiency of the lithography machine, it is necessary to continuously increase the moving speed of the stepping and exposure scanning of the wafer stage. The increase of speed will inevitably lead to the deterioration of the dynamic performance of the system. Therefore, a large number of technical measures are needed to ensure and improve the motion accuracy of the wafer stage, and the cost to maintain the existing precision or achieve higher precision will be greatly improved. .

The structure described in the patent W098/40791 (publication date: 1998.9.17, country: Netherlands) adopts a double silicon wafer stage structure, and transfers exposure preparations such as upper and lower sheets, pre-alignment and alignment to the second wafer stage. Up and independently moving simultaneously with the exposed wafer stage. Under the premise of not increasing the moving speed of the silicon wafer stage, a large amount of preparation work for the exposed silicon wafer stage is shared by the second silicon wafer stage, thereby greatly shortening the working time of each silicon wafer on the exposed silicon wafer stage, and greatly improving Production efficiency. However, the main drawback of this system is the non-centroidal drive problem of the wafer stage system.

The invention patent filed by the applicant in 2007 "a lithography machine wafer table double exchange system" (publication number: CN101101454 A dual-disc exchange system of a lithography machine is disclosed, which has the advantages of simple structure and high exposure efficiency. However, the dual silicon wafer exchange system also has some problems. First, the air bearing needs to exchange the guiding surface when the wafer table is exchanged, resulting in extremely high precision requirements for the dimensional consistency of the silicon wafer table, processing and assembly of the components. The accuracy is required to be above the micron level; the second is that it is difficult to install sensors for detecting mutual position between the guide rails involved in the exchange, and the collision between the linear guide rails may occur; the third is the non-centroid drive of the silicon wafer stage system; the fourth is the silicon wafer stage. The space utilization of the system is not high enough.

technical problem

The invention aims at the deficiencies and shortcomings of the existing two-station switching system of the silicon wafer stage of the lithography machine, and proposes a two-slice switching system and a switching method for the lithography machine silicon wafer table, so as to overcome the existing silicon wafer table double-station switching system. The advantages of centroid driving, space utilization is not high enough, and processing and assembly precision are extremely high, so that it has the advantages of simple structure, high space utilization, and no collision between linear guide rails during exchange, and further improves the lithography machine. s efficiency.

Technical solution

The technical solution of the present invention is as follows:

A lithography machine wafer table double exchange system, the system comprises a first wafer stage running at an exposure station, a second wafer stage running at a pretreatment station, a base station, and a first X direction linear guide a second X-direction linear guide, a first single-degree-of-freedom auxiliary drive unit, a second single-degree-of-freedom auxiliary drive unit, a third single-degree-of-freedom auxiliary drive unit, a fourth single-degree-of-freedom auxiliary drive unit, and a first Y-direction guide, a second Y-direction guide rail, a first wafer stage auxiliary driving unit and a second wafer stage auxiliary driving unit, the first Y-direction rail passes through the first wafer stage, and the second Y-direction rail passes through the second wafer stage; Characterized in that the system further includes a first main driving unit disposed on the first X-direction linear guide and a second main driving unit disposed on the second X-directional linear guide; the first main driving unit has a degree of freedom of movement in the X direction and a degree of freedom of rotation perpendicular to the plane of the base, the first main drive unit being coupled to one end of the first Y-direction rail, and the other end of the first Y-direction rail and the third single free Auxiliary drive unit or fourth single The second main driving unit has a degree of freedom of movement in the X direction, the second main driving unit is coupled to one end of the second Y-direction rail, and the other end of the rail and the first single degree of freedom The auxiliary driving unit or the second single-degree-of-freedom auxiliary driving unit is docked; the Y-direction guide rail and the single-degree-of-freedom auxiliary driving unit adopt a separate structure, and are disconnected when the two wafer table positions are exchanged.

The lithography machine silicon wafer table double exchange system provided by the invention is characterized in that: the first main driving unit is composed of a linear motor mover, a torque motor and a vacuum preloaded air bearing, or is driven by a stepping motor. Substituting the linear motor mover, the vacuum preload air bearing is replaced by a permanent magnet preloaded air floating shaft; the second main drive unit is composed of a linear motor mover and a vacuum preloaded air bearing. Or use a stepper motor mover instead of the linear motor mover, and replace the vacuum preloaded air bearing with a permanent magnet preloaded air bearing.

In the above technical solution, a ball guide or an air bearing is mounted between the top of the first main driving unit and the first X-direction rail, and between the top of the second main driving unit and the second X-direction rail. Supporting; the bottom of the first main driving unit and the second main driving unit are respectively equipped with a linear motor mover, and the bottom surface in contact with the base is equipped with a permanent magnet preloaded air bearing; the first single free The bottom auxiliary drive unit, the second single degree of freedom auxiliary drive unit, the third single degree of freedom auxiliary drive unit and the fourth single degree of freedom auxiliary drive unit are each equipped with a linear motor mover, and the side contacting the base is equipped The vacuum preloaded air bearing, the bottom surface in contact with the base is equipped with a permanent magnet preloaded air bearing.

The lithography machine wafer table double-station exchange system of the present invention further comprises a dual-frequency laser interferometer for moving position feedback of the silicon wafer stage; in the first main driving unit, the second main driving unit, and the first Single degree of freedom auxiliary drive unit, second single degree of freedom auxiliary drive unit, third single degree of freedom auxiliary drive unit, fourth single degree of freedom auxiliary drive unit, first wafer stage auxiliary drive unit, and second wafer stage auxiliary drive A linear grating for position feedback is mounted on the unit.

The invention provides a method for exchanging a silicon wafer stage of a lithography machine, characterized in that the exchanger performs the following steps:

a) When the two silicon wafer stages are exchanged, first, the first main driving unit drives the first Y-direction guide rail and the first silicon wafer stage to perform a clockwise rotation motion in the plane of the base plane, and at the same time, the first silicon wafer stage auxiliary drive The unit drives the first wafer stage to move along the first Y-direction guide toward the first main drive unit, and the third single-degree-of-freedom auxiliary drive unit moves in the positive X direction;

b) when the first Y-direction guide rail is parallel to the first X-direction guide rail, the second main drive unit drives the second Y-direction guide rail and drives the second wafer stage to move in the positive X direction, and at the same time, the second wafer stage along the second The two Y-direction rails move toward the second main driving unit, and the first Y-direction guide rail and the first silicon wafer stage are driven in the negative X direction by the driving of the first main driving unit, and the first single-degree-of-freedom auxiliary driving unit is also along the X negative direction. Directional movement

c) when the second Y-direction guide rail and the second wafer stage move from one side of the first Y-direction guide rail and the first wafer stage to the other side, the first main drive unit drives the first Y-direction guide rail and the first The wafer stage rotates counterclockwise in the plane of the base, and at the same time, the fourth single degree of freedom auxiliary driving unit moves to the corresponding position of the first Y direction guide rail and abuts thereto, and the second single degree of freedom auxiliary drive unit moves to the first The corresponding positions of the two Y-direction guide rails are docked with each other, thus completing the position exchange of the first wafer stage and the second wafer stage, and proceeding to the next cycle.

Beneficial effect

Compared with the prior art, the invention has the following outstanding advantages: one is that the wafer stage of the system is driven by the centroid; the other is that the exchange surface is not exchanged by the air bearing, which reduces the requirement of dimensional consistency; the third is four auxiliary The drive units are single-degree-of-freedom, simplifying the control system structure and reducing the installation accuracy requirements of system components. Fourth, the space utilization and system efficiency are further improved.

DRAWINGS

Figure 1 is a schematic diagram of the working principle of the lithography machine.

2 is a state diagram of a wafer stage dual stage exchange system of a lithography machine of the present invention and before exchange.

Figure 3 shows the structure of the drive unit on both sides of the wafer stage.

Figure 4 shows the structure of the wafer stage and the Y-direction guide.

Figure 5 shows the connection between the wafer stage, the Y-direction guide and the single-degree-of-freedom auxiliary drive unit.

Figure 6 shows the structure of a two degree of freedom main drive unit.

Figure 7 shows the structure of a single degree of freedom auxiliary drive unit.

Figure 8 shows the exchange process for two wafer stages.

In the figure: 1 - first single degree of freedom auxiliary drive unit; 2 - first X direction guide; 3 - first wafer stage; 4 - first Y direction guide; 5 - base; 6 - second X direction guide ; 7 - second single degree of freedom auxiliary drive unit; 8 - second wafer stage; 9 - second Y direction guide; 10 - first main drive unit; 11 - first wafer stage auxiliary drive unit; Two-silicon wafer auxiliary driving unit; 13-second main driving unit; 14-torque motor; 15-third single-degree-of-freedom auxiliary driving unit; 16-fourth single-degree-of-freedom auxiliary driving unit; 17-single-degree-of-freedom driving unit Linear motor mover; 18—main drive unit linear motor mover; 19-vacuum preloaded air bearing; 20—permanent magnet preloaded air bearing; 21—Y direction guide linear motor stator magnet; 22—silicon wafer stage Bottom air bearing; 23-Y direction guide air bearing; 24 - closed preloaded air bearing; 25a - Y direction rail butt side; 25b - single degree of freedom auxiliary drive unit butt side; 26 - light source; Stencil; 28-lens system; 29-silicon wafer.

Embodiments of the invention

The structure, principle and working process of the present invention will be further described below with reference to the accompanying drawings.

2 is a schematic structural view of a wafer stage dual-disc exchange system of a lithography machine provided by the present invention, the system comprising a first wafer stage 3 operating at an exposure station, and a second wafer stage 8 operating at a pretreatment station. a first X-direction linear guide 2, a second X-direction linear guide 6, a first single-degree-of-freedom auxiliary drive unit 1, a second single-degree-of-freedom auxiliary drive unit 7, a third single-degree-of-freedom auxiliary drive unit 15, and a fourth single Degree of freedom auxiliary drive unit 16, first Y-direction guide rail 4, second Y-direction guide rail 9, first wafer stage auxiliary drive unit 11, second wafer stage auxiliary drive unit 12, first main drive unit 10, second The main driving unit 13 and the base 5, the long side of the base is the X direction, and the short side is the Y direction; the first main driving unit 10 has the degree of freedom of movement in the X direction and the degree of freedom of rotation perpendicular to the plane of the base, a main driving unit is coupled to one end of the first Y-direction rail, and the other end of the first Y-direction rail is coupled to the third single-degree-of-freedom auxiliary driving unit or the fourth single-degree-of-freedom auxiliary driving unit; the second main driving Unit 13 has a degree of freedom of movement in the X direction, the second main The moving unit is coupled to one end of the second Y-direction guide rail 9, and the other end of the second Y-direction rail rail is docked with the first single-degree-of-freedom auxiliary driving unit 1 or the second single-degree-of-freedom auxiliary driving unit 7; The guide rail is driven by the main drive unit or driven by the single-degree-of-freedom auxiliary drive unit to realize the movement of the wafer stage in the X direction, and the Y-direction guide rail and the single-degree-of-freedom auxiliary drive unit adopt a separate structure, in two The wafer stage is disconnected when the position is exchanged.

The first main driving unit 10, the third single degree of freedom auxiliary driving unit 15 and the fourth single degree of freedom auxiliary driving unit 16 share the first Y direction linear guide 4; the second main driving unit 13, the first single degree of freedom auxiliary driving unit 1 and the second single-degree-of-freedom auxiliary driving unit 7 share the second Y-direction linear guide 9; the first Y-direction guide 4 passes through the first wafer stage 3, one end of the first Y-direction guide 9 and the first main driving unit 10 Coupling, the other end is coupled with the third single-degree-of-freedom auxiliary driving unit 15 , and the first driving unit 10 and the third single-degree-of-freedom auxiliary driving unit 15 are driven together to realize the movement of the first wafer stage in the X direction; The first Y-direction guide rail 4 can realize a rotary motion perpendicular to the plane of the base plate under the driving of the first main drive unit 10; the second Y-direction guide rail 9 passes through the second wafer stage 8, and one end of the second Y-direction guide rail The second main driving unit 13 is coupled, and the other end is connected to the first single-degree-of-freedom auxiliary driving unit 1. When the second main driving unit 13 and the first single-degree-of-freedom auxiliary driving unit 1 are driven together, the second silicon wafer stage can be realized. Move in the X direction.

3 and 4 show the structure and connection mode of the wafer stage, the X-direction guide rail, the Y-direction guide rail, the air bearing, the single-degree-of-freedom auxiliary drive unit, the main drive unit, and the first single-degree-of-freedom auxiliary drive unit 1, The bottoms of the two single-degree-of-freedom auxiliary driving unit 7, the third single-degree-of-freedom auxiliary driving unit 15, and the fourth single-degree-of-freedom auxiliary driving unit 16 are all equipped with a linear motor mover, and the bottom surface in contact with the base is equipped with a permanent magnet pre-prepared a carrier air bearing or a vacuum preload air bearing, the stator is mounted on the base 5, and the third single degree of freedom auxiliary driving unit or the fourth single degree of freedom auxiliary driving unit is docked with the first Y direction rail 4, and A main driving unit 10 cooperates to jointly drive the first silicon wafer table to move in the X direction; the coupling manner of the X direction guide rail and the main driving unit can be realized by using a ball guide or an air bearing guide, a magnetic force or a vacuum preload; The connection mode of the guide rail and the main drive unit is realized by means of screw fixing, and the other end is connected with a single-degree-of-freedom auxiliary driving unit, and electromagnetic or vacuum adsorption is adopted to achieve precise docking; Y-direction The rail is driven by a torque motor, a linear motor or a stepper motor to achieve rotational motion and movement in the X direction.

Figure 4 shows the coupling structure of the wafer stage and the Y-direction guide. The bottom of the first wafer stage 3 is provided with a vacuum preloaded air bearing, the upper surface of the base is a guiding surface, the first Y direction rail 4 penetrates from the inside of the first wafer stage 3, and the first Y direction rail 4 is mounted with Y. The directional guide linear motor stator magnet, the coil is mounted as a linear motor mover on the wafer stage; the two inner vertical faces of the first wafer stage 3 are also equipped with a closed preload air bearing to constrain the first wafer stage 3 Move along the guide rail in the Y direction.

Figure 5 shows the coupling between the first Y-direction rail 4 and the single-degree-of-freedom auxiliary drive unit 15. The third single-degree-of-freedom auxiliary driving unit 15 is docked with the first Y-direction guide rail 4, and the joint surface can be accurately docked and detached by electromagnetic or vacuum adsorption to achieve position exchange of the wafer stage.

Figure 6 shows the structure of the first main drive unit. The first main driving unit 10 is equipped with a linear motor mover 18 and a torque motor 14, which has two degrees of freedom of translation and rotation, and is driven by a torque motor, a linear motor or a stepping motor, and can realize translation in the X direction. And rotating around the first main driving unit; the bottom of the first main driving unit 10 and the second main driving unit 13 are respectively equipped with linear motor movers 18, and the bottom surface is equipped with a permanent magnet preloaded air bearing 20, and the Y direction A ball guide or an air bearing is used as a guide support between the guide rails.

Figure 7 shows the structure of a single degree of freedom auxiliary drive unit. The single-degree-of-freedom auxiliary drive unit and the main drive unit drive the wafer stage to move in the X direction. The single-degree-of-freedom auxiliary drive unit is equipped with a linear motor mover 17 at the bottom, and a vacuum preloaded air bearing 19 is mounted on the side. Both are equipped with permanent magnet preloaded air bearing.

Figure 8 shows the exchange process of the two-slice switching system of the wafer stage of the lithography machine of the present invention, which is carried out as follows:

a) The two silicon wafer stages are in a position state before the exchange, that is, the third single-degree-of-freedom auxiliary driving unit 15 is docked with the first Y-direction guide rail 4, and drives the first silicon wafer stage 3 together with the first main driving unit 10 for exposure. The first single-degree-of-freedom auxiliary driving unit 1 is docked with the second Y-direction guide rail 9, and cooperates with the second main driving unit 13 to drive the second wafer stage 8 in the pre-processing station, and the silicon wafer stage respectively performs pre-processing. After the exposure process, the system enters the dual exchange state;

b) First, the first Y-direction guide rail 4 is disengaged from the third single-degree-of-freedom auxiliary drive unit 15, and the first main drive unit 10 drives the first Y-direction guide rail 4 and drives the first wafer stage 3 to be compliant in the plane of the base station. In the hour hand direction, the first wafer stage auxiliary driving unit 11 drives the first wafer stage 3 to move in the direction of the first main direction driving unit 4 toward the first main driving unit 10, and the third single degree of freedom auxiliary driving unit 15 Moving in the positive X direction, as shown in Fig. 7(a), until the first Y-direction guide rail 4 is parallel to the first X-direction guide rail 2;

c) Secondly, the second Y-direction guide rail 9 is disengaged from the first single-degree-of-freedom auxiliary drive unit 1, and the second main drive unit 13 drives the second Y-direction guide rail 9 and drives the second wafer stage 8 to move in the positive X direction. The second wafer stage 8 moves in the direction of the second main drive unit 13 along the second Y-direction guide rail 9, and the first Y-direction guide rail 4 and the first wafer stage are driven in the negative X direction by the first main drive unit 10. Movement, the first single degree of freedom auxiliary drive unit 1 also moves in the negative X direction, moving to the edge stop, as shown in Figure 7 (b);

d) Then, when the second Y-direction guide rail 9 and the second wafer stage 8 are moved from one side of the first Y-direction guide rail 4 and the first wafer stage 3 to the other side, the first main drive 10 drives the first A Y-direction guide rail 4 drives the first wafer stage 3 to rotate counterclockwise, and at the same time, the wafer stage 3 moves in a direction away from the first main drive 10, and the second single-degree-of-freedom auxiliary drive unit 7 follows X negative Directional movement, the fourth single degree of freedom auxiliary drive unit 16 moves in the positive X direction, as shown in Figure 7 (c);

e) Finally, when the first Y-direction guide 4 is parallel to the Y direction under the driving of the first main drive unit 10, the fourth single-degree-of-freedom auxiliary drive unit 16 moves to the corresponding position of the first Y-direction guide 4 and Docking, and driving the first wafer stage 3 to move to the initial position of the pretreatment station together with the first main driving unit 10 and the first wafer stage auxiliary driving unit 11, and the second single degree of freedom auxiliary driving unit 7 moves to the first position Corresponding positions of the two Y-direction guide rails 9 and docking with them, and driving the second wafer stage 8 together with the second main driving unit 13 and the second auxiliary driving unit 12 to move to the initial position of the exposure station, as shown in FIG. 7(d) As shown, the first wafer stage 3 and the second wafer stage 8 have now completed the position exchange and started the next cycle.

Claims

[Correct according to Rule 91 06.01.2011]
1. A lithography machine wafer table double exchange system, the system comprises a first wafer stage (3) running at an exposure station, a second wafer stage (8) running at a pretreatment station, a base station ( 5), the first X direction linear guide (2), the second X direction linear guide (6), the first single degree of freedom auxiliary drive unit (1), the second single degree of freedom auxiliary drive unit (7), the third single Degree of freedom auxiliary drive unit (15), fourth single degree of freedom auxiliary drive unit (16), first Y direction guide rail (4), second Y direction guide rail (9), first wafer stage auxiliary drive unit (11) And a second wafer stage auxiliary driving unit (12), the first Y-direction rail (4) passes through the first wafer stage (3), and the second Y-direction rail (9) passes through the second wafer stage (8) Characterized in that the system further comprises a first main drive unit (10) disposed on the first X-direction linear guide (2) and a second main drive unit disposed on the second X-direction linear guide (6) (13); the first main drive unit (10) has a degree of freedom of movement in the X direction and a rotation perpendicular to the plane of the basement Degree, the first main driving unit (10) is connected to one end of the first Y-direction rail (4), the other end of the first Y-direction rail (4) and the third single-degree-of-freedom auxiliary driving unit (15) Or the fourth single-degree-of-freedom auxiliary driving unit (16) is docked; the second main driving unit (13) has a degree of freedom of movement in the X direction, and the second main driving unit (13) and the second Y-direction rail (9) One end of the rail is connected, and the other end of the rail is docked with the first single degree of freedom auxiliary driving unit (1) or the second single degree of freedom auxiliary driving unit (7); the Y direction rail and the single degree of freedom auxiliary driving unit are adopted Separate structure, disconnected when the two wafer stage positions are swapped.
[Correct according to Rule 91 06.01.2011]
2. A lithography wafer stage double-disc switching system according to claim 1, wherein said first main driving unit (10) is composed of a main driving unit linear motor mover (18) and a torque motor ( 14) or vacuum preloaded air bearing (20), or replaced by a stepper motor, the permanent magnet preloaded air floating shaft replaces the vacuum preloaded air bearing; The two main driving units (13) are composed of a main driving unit linear motor mover (18) and a vacuum preloaded air bearing (20), or a stepping motor is used instead of the linear motor, and a permanent magnet preloaded air bearing is used instead of Among them are vacuum preloaded air bearing.
[Correct according to Rule 91 06.01.2011]
3. A lithography wafer table double-station exchange system according to claim 1, wherein: between the top of the first main driving unit (10) and the first X-direction rail (2), A ball guide or an air bearing is mounted as a guide support between the top of the two main drive units (13) and the second X-direction guide rail (6); the first main drive unit (10) and the second main drive unit (13) The bottom surface in contact with the abutment (5) is equipped with a permanent magnet preloaded air bearing.
[Correct according to Rule 91 06.01.2011]
4. A lithography machine wafer stage dual-disc switching system according to claim 1, wherein said first main driving unit (10), said second main driving unit (13), and said first single free Auxiliary drive unit (1), second single degree of freedom auxiliary drive unit (7), third single degree of freedom auxiliary drive unit (15), fourth single degree of freedom auxiliary drive unit (16), first wafer support A linear grating for position feedback is mounted on the linear motor of the drive unit (11) and the second wafer stage auxiliary drive unit (12), respectively.
[Correct according to Rule 91 06.01.2011]
5. A lithography wafer stage dual-disc switching system according to claim 1, 2, 3 or 4, characterized in that: said first single degree of freedom auxiliary driving unit (1), second single degree of freedom A linear motor mover (17) is mounted on the bottom of the auxiliary drive unit (7), the third single-degree-of-freedom auxiliary drive unit (15), and the fourth single-degree-of-freedom auxiliary drive unit (16), and is in contact with the base (5) The side is equipped with a vacuum preloaded air bearing (19), and the bottom surface in contact with the base (5) is equipped with a permanent magnet preloaded air bearing (20).
[Correct according to Rule 91 06.01.2011]
6. A lithography machine wafer stage dual-disc switching system according to claim 5, wherein said lithography machine wafer stage dual-disc switching system further comprises dual-frequency for silicon wafer stage motion position feedback. Laser interferometer.
[Correct according to Rule 91 06.01.2011]
7. A method for switching a silicon wafer stage of a lithography apparatus according to the system of claim 1, wherein the switching party performs the following steps: a) When the two silicon wafer stations exchange positions, first, the first main driving unit (10) driving the first Y-direction guide rail (4) and the first wafer stage (3) to perform a clockwise rotation motion in the plane of the base station (5), and simultaneously driving the first wafer stage auxiliary driving unit (11) The first wafer stage (3) moves along the first Y-direction guide rail (4) toward the first main drive unit (10), and the third single-degree-of-freedom auxiliary drive unit (15) moves in the positive X direction; b) When the first Y-direction rail (4) is parallel to the first X-direction rail (2), the second main driving unit (13) drives the second Y-direction rail (9) and drives the second wafer stage (8) along the X-direction Directional movement, at the same time, the second wafer stage (8) moves along the second Y-direction rail (9) toward the second main driving unit (13), the first Y-direction rail (4) and the first wafer stage (3) Moving in the negative X direction under the driving of the first main driving unit (10), the first single degree of freedom auxiliary driving unit (1) Also moving in the negative X direction; c) when the second Y-direction rail (9) and the second wafer stage (8) are moved from the side of the first Y-direction rail (4) and the first wafer stage (3) to On the other side, the first main driving unit (10) drives the first Y-direction rail (4) and the first wafer stage (3) to perform a counterclockwise rotation motion in the plane of the base, and at the same time, the fourth single degree of freedom assists The driving unit (16) moves to and abuts a corresponding position of the first Y-direction rail (4), and the second single-degree-of-freedom auxiliary driving unit (7) moves to a corresponding position of the second Y-direction rail (9) and Docking, thus completing the positional exchange of the first wafer stage (3) and the second wafer stage (8), and proceeding to the next cycle.