METHOD OF MEASURING A PHASE OF A PHASE SHIFT MASK AND APPARATUS FOR PERFORMING THE SAME

摘要

In a method of measuring a phase of a phase shift mask, initial extreme ultraviolet (EUV) light is divided into secondary EUV light portions. The secondary EUV light portions are irradiated onto the phase shift mask as incident EUV light portions, and the phase of the phase shift mask is measured from reflected incident EUV light portions.