Observation of thermal desorption and MBE growth rate using laser light scattering

We applied Laser Light Scattering (LLS) to study oxide surface desorption o n InSb substrates, and the subsequent growth of CdTe layers by molecular be am epitaxy. LLS measurements allowed us to determine the critical temperatu re before surface degradation of InSb, which is not clearly noticed by Refl ection High Energy Electron Diffraction (RHEED). Surface defects appeared o n substrates where this temperature was exceeded, as observed by Scanning E lectron Microscopy (SEM) and Atomic Force Microscopy (AFM). During the MBE growth of CdTe on InSb, two features were noticed in LLS measurements. Firs t, a decrease in intensity was observed that can be associated to a change in surface roughness at the initial stages of growth. The second feature is an oscillatory behavior, which can be related to interference. A geometric al model of interference in thin films was used to calculate the layer thic kness in real time. (C) 2000 Elsevier Science S.A. All rights reserved.