Surface Morphology of MBE-grown GaN on GaAs(001) as Function of the N/Ga-ratio
O. Zsebök, J.V. Thordson, T.G. Andersson
Chalmers University of Technology
This article was received on Tuesday, June 23, 1998 and
accepted on Monday, August 24, 1998. Abstract
Molecular
beam epitaxy growth utilising an RF-plasma nitrogen source was used to study
surface reconstruction and surface morphology of GaN on GaAs (001) at 580
°C. While both the nitrogen flow and plasma excitation power were
constant, the grown layers were characterised as a function of Ga-flux. In the
initial growth stage a (3x3) surface reconstruction was observed. This surface
periodicity only lasted up to a maximum thickness of 2.5 ML, followed by a
transition to the unreconstructed surface. Samples grown under N-rich, Ga-rich
and stoichiometric conditions were characterised by high-resolution scanning
electron microscopy and atomic force microscopy. We found that the smoothest
surfaces were provided by the N/Ga-ratio giving the thickest layer at the
(3x3)=>(1x1) transition. The defect formation at the GaN/GaAs interface also
depended on the N/Ga-flux ratio.Outline
Linked Pages
Cite this article as: MRS Internet J. Nitride Semicond. Res. 3, 14(1998).
last updated Monday, August 24, 1998 5:44:18 PM.© 1998 The Materials Research Society
