Imaging interference photo etching method and system by rotating a mask and a resist silicon slice

Abstract

The imaging interference lithography method of rotating mask and resist silicon wafer is, using a precision rotating mechanism, after two exposures of low-frequency and high-frequency components in x-direction by illuminating the mask with vertical light and obliquely illuminating the mask in x-direction, The mask and the resist silicon wafer are rotated 90° synchronously, and then the high-frequency component exposure in the y direction is performed to realize the third exposure required for imaging interference lithography to form the final high-resolution mask imaging. The principle of this method is simple, without using multiple lasers with different wavelengths or frequency shifting devices, which reduces the cost of system equipment, simplifies system structure, adjustment, and alignment, and uses shutters to control exposure time, and uses variable filters to adjust exposure light intensity ratio. , and between low-frequency component and high-frequency component exposure, a fully reflective mirror that can be rotated in and out is used to improve the utilization rate of laser energy, and finally achieve high-resolution, high-quality imaging. The invention makes it unnecessary to adjust the optical path in real time between the three exposures, and can realize imaging interference lithography with one laser of one wavelength, reduces the adjustment and alignment difficulties between the three exposures, and shortens the time required for the three exposures. time to improve exposure efficiency.

Description

technical field [0001] The invention relates to an imaging interference photolithography method and a photolithography system for rotating a mask and resist silicon wafer, and belongs to the improvement and implementation of the imaging interference photolithography method and system for producing high-resolution fine patterns. technical background [0002] Laser interference lithography technology uses the interference between beams to produce periodic pattern arrays. Its limitation is that it can only produce periodic patterns, and it is difficult to produce a variety of arbitrary patterns required for the production of integrated circuits in the microelectronics industry. For this reason, people have proposed an imaging interference lithography technology that can not only improve the resolution but also produce arbitrary patterns. The general imaging interference lithography method uses a mask and a resist silicon wafer to fix, and changes the direction of the illuminati...

AI Technical Summary

Problems solved by technology

[0005] However, this imaging interference lithography method is difficult to adjust the optical path and pattern alignment in real time between three exposures, and alignment errors will cause pattern distortion, affect pattern quality and fidelity, and reduce exposure efficiency

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