Double-driving double-bridge table changing station-based double-workpiece table high-accuracy exchange device

Abstract

The invention relates to a double-driving double-bridge table changing station-based double-workpiece table high-accuracy exchange device, which belongs to semiconductor manufacturing equipment and technology. The device is provided with a table changing station with double-driving double-bridge structure; two groups of double-driving bridge type structures are formed by symmetrically arranging two U-shaped groove type linear motor stators and static pressure air flotation guide rails respectively; in the double-driving double-bridge structure, air flotation guide rails in an X direction and a Y direction are changed into short guide rails, so that the size and inertia of a driven body can be reduced remarkably, start and stop driving speeds can be increased and response time and positioning stabilizing time are shortened; and a long-travel linear movement unit of a silicon chip table adopts a strict synchronous driving form for double linear motors arranged in parallel symmetrically in the X direction and the Y direction and driving force passes through the mass center of the silicon chip table, so that the disturbance on the inertia turning moment of the silicon chip table is reduced effectively, the stability and reliability of a system are enhanced and the realization of dynamic and static positioning accuracies of the system is guaranteed reliably.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing equipment, and mainly relates to a high-precision exchange device for double workpiece tables based on a double-drive double-bridge table-changing station. Background technique [0002] Lithography machine is one of the important ultra-precision equipment in the manufacture of very large-scale integrated circuits. It is divided into stepping lithography machine and scanning lithography machine. The workpiece table technology is one of the core technologies of the lithography machine, and its main feature is to achieve ultra-precision motion control with high speed and high acceleration and deceleration. The ultra-precise movement of the workpiece table of the lithography machine is used to cooperate with the processing and manufacturing processes such as loading, pre-alignment, alignment, exposure and unloading in the lithography process. Whether it is step-and-repeat exposure...

AI Technical Summary

Problems solved by technology

However, the current double worktable system is limited by the mechanical structure, and it is difficult to ensure that each of them can realize the symmetrical double drive mode in the X and Y directions. Generally, the dual drive mode is used in the Y direction, and a single motor is used in the X direction. drive mode

For example, patent 200610116453.6 adopts this asymmetrical driving method. The main problem is that the single motor drive will cause the direction of the driving force to not reach the center of mass of the silicon wafer stage, and torque will appear due to the asymmetrical inertial force during the movement process.

Secondly, the air bearing guide rail is longer, which increases the volume inertia of the driven body, which is not conducive to improving the starting and stopping driving speed and shortening the response time and positioning stability time

The rigidity of the static pressure air bearing guideway of the lithography machine system is relatively low, and the silicon wafer table is prone to large inertia torque disturbance under high speed and high acceleration and deceleration, which will have a serious impact on the motion positioning accuracy of the silicon wafer table , it will also reduce the reliability of the system

For example, patent 200710119275.7 uses 4 dual-degree-of-freedom drive units to push and pull the silicon wafer stage to realize the table-changing movement. Although this patent simplifies the system structure, it is difficult to find the center of mass of the silicon wafer stage, which leads to problems in the movement process. large torque disturbance

For example, the patent 200810137566.3 embeds the stator of the linear motor into the abutment, and the upper surface of the stator of the linear motor and the reference surface of the abutment are ground as the air-floating working surface, but the upper surface of the stator of the linear motor is used as a part of the air-floating working surface, which destroys the air-floating working surface. Integrity, which reduces the stability and reliability of the air bearing, and the high flatness requirement increases the difficulty of grinding, and the structure is difficult to realize

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