A simple and practical 157nm and 193 nm coherent light source

We demonstrate a fully-coherent ultrafast UV light source at 193 and 157 nm using a cascaded four wave mixing technique in a hollow dielectric waveguide. We have obtained 200 nJ and 20 nJ per pulse energy at 193 nm and 157 nm respectively using pulses of 200 uJ pulse energy and 50 fs pulse width from a Ti:sapphire regenerative amplifier at 5 kHz. Our technique can easily be scaled to 100 kHz repetition rate for use in defect inspection for lithography development and many ultrafast spectroscopy experiments.