Abstract

Photogenerated electron transfer can play a large role in surface chemical reactions. These electrons have been shown to play a role in adsorption, desorption, and dissociation of semiconductor surfaces.¹ Deep UV photons can photoemit carriers into energy bands and states not accessible by photogenerated carriers created by visible light. As an example, we describe the sharp increase in the photoenhanced oxidation rate on GaAs in the presence of deep UV radiation (4.1 eV < hv < 5.1 eV). In contrast to previous experiments using visible radiation,² the deep UV reaction enhancement occurs at oxide coverages of more than one monolayer (ML), and the oxide formation under deep UV irradiation can exceed several monolayers.

© 1990 Optical Society of America