全自动光刻机自动对准与激光扫描光学系统

本文首先概述了全自动光刻机的对准光学系统,接着详细阐述了激光扫描实时检测对准误差的基本原理,分析了扫描对准光学系统的设计要求,讨论了设计时应该遵循的原则、设计方法、设计步骤和有关方案,并给出了部分测试结果.

The Principle of Self-Alignment in an Auto-Photoetching Machine by Laser Scanning and Design of an Optical System

The design layout of the optical aligning system in an auto-photoetching machine is described. The principle of real-time detection of an aligning error is demonstrated, involving the scanning of an aligning pattern by a laser beam at constant speed, the processing of the diffracted wave produced by a pattern with optical spatial filtering and the accurate measurement of the aligning error by pulse spacing. Design requirements on the optical scanning system are analyzed. The principle, method, procedures and some design layouts of the optical scanning system are discussed. Part of the test results are given. The outputs ignal strength of the aligning system is greater than 1.4V and the signal-to-noise ratio is greater than 20 dB.