Imaging interference photo etching method using two quadrature acousto-optic modulators and photo etching system

Abstract

The imaging interference lithography method and photolithography system using two orthogonal acousto-optic modulators are characterized in that two orthogonal acousto-optic modulators are used to deflect the laser beam emitted from the laser, and when the acousto-optic modulator is on When no ultrasonic power is applied, the laser light directly passes through the acousto-optic modulator to provide vertical illumination for the mask; when the acousto-optic modulator is supplied with ultrasonic power of a certain frequency, it produces first-order diffracted light whose deflection angle is proportional to the ultrasonic frequency , to provide illumination for offset exposure in the horizontal direction and offset exposure in the vertical direction. By changing the ultrasonic power, the intensity of the first-order diffracted light can be easily adjusted, and the exposure intensity control without attenuating filters can be realized. The deflection can be controlled in real time by changing the ultrasonic frequency. The size of the angle can conveniently, flexibly and quickly realize three exposures of imaging interference lithography, and produce high-fidelity resist patterns.

Description

Technical field [0001] The invention relates to an imaging interference lithography method and a lithography system using two orthogonal acousto-optic modulators, and belongs to the improvement of the imaging interference lithography technique for generating fine patterns. Background technique [0002] Imaging interference lithography technology is a new technology that improves the resolution of lithography. Its main feature is to use three exposures to expose the low-frequency components of the mask pattern, the high-frequency components in the x direction and the y direction, and optimize the relative exposure intensity. Improve the resolution of photolithography and improve the quality of exposed graphics. The general imaging interference lithography system consists of laser, beam splitter, mirror, spatial filter, beam expander collimator, mask, imaging optical lens and resist substrate, etc. Document Xiaolan Chen and S. RJ Brueck Imaging Interferometric lithography for arbit...

AI Technical Summary

Problems solved by technology

However, there are too few studies on the specific implementation system and the practical application of the system. Generally, the adjustment of the optical path between exposures is used to achieve three exposures. Image alignment is the key issue that has not been resolved, and the exposure efficiency is not high, which is not conducive to popularization and application.

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