Abstract
Deep ultraviolet (DUV) lasers are widely used in the semiconductor industry. Photolithographic
exposure tools typically employ pulsed excimer lasers operating at 10’s of Watts average power, whereas
wafer- and mask-inspection applications utilize lower-power, solid-state, continuous-wave (CW) and
quasi-continuous-wave (QCW) ultraviolet (UV) lasers based on nonlinear frequency conversion. In this
paper, we review recent technology trends of DUV light sources developed for photomask inspection
tools.
