Free hook face lens used for DMD (Digital Micromirror Device) photoetching image system, and design method thereof

Abstract

The invention discloses a free hook face lens used for a DMD (Digital Micromirror Device) photoetching image system, and a design method thereof, and belongs to the field of the optical technology. Adistance between a DMD single micromirror and a free hook face lens is 1mm, the material of the free hook face lens is silicon crystal, the outer outline size of the free hook face lens is 12mm*21mm,the thickness of the free hook face lens is 1mm, the front surface face type of the free hook face lens is a plane, the rear surface face type of the free hook face lens is a free hook face, and the maximum distortion amount of the free hook face lens is 10.63[mu]m. The method comprises the following steps that: calculating the linear dislocation of the DMD single micromirror which can smoothly carry out photoetching on pattern edges, designing the free hook face lens with special distortion characteristics, and carrying out modeling on a projection and imaging system. By use of the free hookface lens, DMD scanning photoetching pattern edge sawteeth can be reduced to obtain optimal photoetching pattern quality.

Description

technical field [0001] The invention belongs to the field of optical technology, and in particular relates to a free-form surface lens with special distortion, which is applied in a photolithography system based on a digital micromirror array and solves the problem of sawtooth on the edge of a DMD maskless scanning photolithography pattern. Background technique [0002] With the rapid development of micro-optoelectronic devices, the DMD-based maskless scanning lithography technology has attracted widespread attention. Its lithography process uses computer optimization to generate a series of "virtual" digital graphics, and controls the projection exposure equipment to project the graphics onto the substrate one by one. In the photolithography process, because there is no superimposition of exposure energy in the scanning direction in other directions, the edge of the reticle has a jagged problem and is not smooth, which greatly reduces the quality of the DMD scanning photoli...

AI Technical Summary

Problems solved by technology

However, when writing complex patterns, the writing efficiency is limited due to the need to process and transmit complex data

(2) Increase the reduction magnification of the imaging lens, which improves the quality of the lithographic pattern to a certain extent, but with the increase of the reduction magnification of the imaging lens, the difficulty of focusing the system increases, and the writing area of ​​a single scan decreases sharply. Photolithography efficiency decreases

However, there are problems such as the difficulty of accurately controlling the tilt angle and the difficulty of system installation and adjustment.

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