Theoretical study of In desorption and segregation kinetics in MBE growth of InGaAs and InGaN

Irena Stanley, University of Nevada, Las Vegas
Golshan Coleiny, University of Nevada, Las Vegas
Rama Venkat, University of Nevada Las Vegas, Department of Electrical & Computer Engineering

Journal of Crystal Growth: Volume 251, Issues 1-4: Pages 23-28

Description

A rate equation model is employed to investigate the surface dynamic processes such as In desorption, incorporation and segregation in the MBE growth of InGaAs and InGaN. In both cases, the agreement between our results and that of the experiment is good. In InGaAs growth, In desorption increases with increasing substrate temperature or group III–V over pressure ratio. The desorption process is observed to have two independent components, one arising from the physisorbed layer of In and the other from the surface of the crystal with activation energies of 0.18 and 2.6 eV, respectively. In InGaN MBE growth studies, In segregation is found to be negligible below 580°C. Above 640°C, the segregation dominates the surface kinetics. This temperature dependence is found to be independent of the fluxes. Activation energy for In segregation is found to be 2.9 eV.