Abstract

Pulsed laser deposition offers a fast and convenient route for preparing crystalline GaN thin films that may be used either directly in devices or as substrates for conventional growth. 3 Jcm^-2 pulses from an excimer laser impinge upon a rotating compressed powder target immersed in a nitrogen or ammonia atmosphere. The resulting ablated plume of material sublimes on a heated sapphire substrate to form the PLD layer. We report here a comparitive study of PLD films and their powder precursor by low temperature photoluminescence (PL) spectroscopy and cathodoluminescence (CL) imaging.

© 1998 IEEE