Real-time monitoring of ellipsometry monolayer oscillations during metalorganic vapor-phase epitaxy

Ellipsometry signal oscillations were clearly seen during metalorganic vapo r-phase epitaxy (MOVPE) of III-V materials under high sample rotation at 14 00rpm. The ellipsometric signal was found to oscillate at a period correspo nding to 1 monolayer of MOVPE growth. Oscillations correlated with the form ation of islands due to nucleation on terraces during the growth of 1 monol ayer. Layer thickness and composition of AlGaAs and InGaAs were precisely d etermined in situ. Critical layer thickness and In composition for InGaAs q uantum dot formation were also evaluated directly from in situ ellipsometry data. (C) 2000 Elsevier Science B.V. All rights reserved.