Surface morphology and electronic structure of bulk single crystal Β -Ga 2 O 3 (100)

Abstract

Experimental studies of the surface morphology and electronic structure of bulk single crystals of the transparent and wide gap semiconductor gallium oxide (Β -Ga 2 O 3) have been conducted using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), and angle-resolved photoemission spectroscopy (ARPES). Atomically resolved STM and LEED results for the Β -Ga 2 O 3 (100) surface clarify that the predominant surface termination contains both gallium and oxygen, and this surface does not exhibit a reconstruction. The valence band structure was obtained with ARPES and shows good agreement with existing theoretical works at the zone center and along the a* and c* directions, except that the calculated bandwidth is ∼7% too small. There is poorer agreement along the b* direction, where the experimental bands disperse more strongly than the calculations. © 2009 American Institute of Physics.