Effect of develop time on process windows in sub-half micron optical lithography

摘要

The effect of develop time (DT) on process control of the sub-half-micron optical lithography step of a production CMOS process is examined. It is shown that develop times greater than those generally used increase the depth-of-focus (DOF), exposure latitude (EL), linearity, exposure margin an resist sidewall angle, thereby improving the process capability. Results are given for both practical experiment and simulation using PROLITH/2. The simulation parameters used have been highly refined to give excellent correlation with experiment over a wide range of conditions.