Characteristics of scanning-probe lithography with a current-controlled exposure system

Abstract

Characteristics of atomic force microscopy lithography using a current-controlled exposure feedback system are investigated by fabricating line-and-space patterns on the negative-type electron beam resist RD2100N. We find that the cross-sectional shape of the developed resist pattern depends on the amount of exposure. The resolution depends on the resist thickness,and a minimum line width of 27 nm is obtained for a 15-nm-thick resist. The proximity effect is evaluated by comparing a resist pattern with a model calculation. Electric-field mapping inside the resist is calculated,and an exposure mechanism is proposed to explain the characteristics.