レーザを用いたリソグラフィ用マスクアライナの開発

Abstract

Precision linear-position control using moire signals have been investigated for a mask-alignment on the lithographic processes. Differential moire technique using two grating pairs 180°out of phase was used. With the reduction of the noises, and improvement of the stability of the laser out put power, the linear-alignment accuracy of ±4nm was obtained. Furthermore, rotational-position control using differential moire technique has been investigated. The rotational-alignment accuracy of ±4×(10)^<-7> rad has been obtained.