Motion platform of lithography machine, micro-motion platform and control method thereof

Abstract

The invention discloses a photoetching machine movement platform and a micro movement platform thereof, and a control method of the micro movement platform. According to the present invention, a reluctance motor and a high-precision voice coil motor are symmetrically distributed and are combined to form the structure of the micro movement platform, wherein the reluctance motor provides high thrusting force required by high acceleration, and the voice coil motor provides high-precision positioning ability, such that the use of the dual motor drive mode integrates the advantages of both motors while the shortcomings of both motors are avoided; according to the control scheme, the double-channel double-motor control mode is used, the feed forward channel comprises the open-loop controlled reluctance motor, the high thrusting force required by the high acceleration / deceleration process of the micro movement platform can be ensured through the high thrusting force property of the open-loopcontrolled reluctance motor, and the bandwidth controlled by the current loop comprising the reluctance motor and the power amplifier is generally greater than the bandwidth controlled by the positionclosed loop so as to easily achieve rapid tracking; and by using the voice coil motor as the feedback control, the precision during the constant-speed movement and the positioning can further be ensured.

Description

technical field [0001] The invention belongs to the field of integrated circuit chip manufacturing, and in particular relates to a motion platform of a photolithography machine, a micro-motion platform and a control method thereof. Background technique [0002] According to Moore's Law, the integration level of integrated circuit chips can be increased by four times every three years, and in recent years there has been a tendency to exceed this law. In the process of rapid development of integrated circuits, lithography equipment has played a basic supporting role. In the scanning lithography machine, on the one hand, the exposure imaging is completed in high-speed motion, and its scanning and positioning accuracy directly affect the imaging accuracy and overlay accuracy of the lithography machine, so its scanning and positioning accuracy need to reach the nanometer level precision. On the other hand, the acceleration and speed of motion directly affect the yield, so high ...

AI Technical Summary

Problems solved by technology

[0005] 1. Linear voice coil motor has the characteristics of low disturbance and high response frequency. It is the best choice for precise control of position, speed and force. It is widely used as the driving mechanism of micro-motion table, but its disadvantages are low efficiency and power consumption. Big

High acceleration requires a high-thrust motor. In the current state that has almost reached its limit, if the next-generation lithography micro-motion table is still driven by a voice coil motor to achieve greater thrust, its size will become very large and it will generate heat. The problem will directly affect the measurement accuracy of the laser interferometer, and the wiring of the supporting cooling water pipes will become very difficult, making the voice coil motor unable to meet the requirements of the micro-motion stage of the next generation lithography machine

[0006] 2. Lorentz force magnetic levitation planar motor may realize the integration of coarse and fine motion, and can realize the large thrust required by high acceleration, but due to the large fluctuation of the motor constant and the difficulty of accurate measurement and compensation, it cannot achieve nanometer precision Requirements, it is expected that voice coil motors will not be replaced for a long time in the future

However, the nonlinear characteristics of the motor make it difficult to control. The uniform motion and positioning accuracy caused by nonlinear hysteresis change with the position, and the repeatability is poor. For applications with micron-level precision, its influence can be ignored, but for Micro-motion table for lithography machine with nanometer precision. If these problems are not solved, it will make it impossible to replace the voice coil motor as the actuator for driving the micro-motion table.

[0008] At present, there is no good drive mechanism or control technology for the next-generation lithography machine micro-table that can meet the requirements of high acceleration, high speed and high-precision movement in lithography.

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