The (3 X 3) reconstruction and its evolution during the nitridation of GaAs(001)

Nitridation of GaAs(001) was performed using a radio frequency nitrogen pla sma source in a molecular beam epitaxy chamber. The nitrogen-induced GaAs(0 01) (3 X 3) reconstruction was investigated by reflection high energy elect ron diffraction (RHEED) and X-ray photoemission spectroscopy (XPS). The tem perature dependence of the (3 X 3) reconstruction as well as its evolution during further nitridation was observed by RHEED; we found that the (3 X 3) reconstruction could be obtained in the temperature range 400-580 degrees C by a very low dose of atomic nitrogen deposition. The nitrogen coverage i n the (3 X 3) reconstruction is determined to be in the range 0.2-0.4 ML us ing XPS. We also discuss the atomic model of the (3 X 3) reconstruction and the energetics of its formation and stability. (C) 1999 Elsevier Science S .A. All rights reserved.