RHEED oscillation studies of pseudomorphic InGaAs strained layers on GaAs substrate

We use reflection high-energy electron diffraction (RHEED) oscillations to study the substrate temperature and In/Ga flux ratio dependencies of the gr owth of pseudomorphic InGaAs layers on GaAs. The growth of InGaAs on GaAs s hows strongly damped oscillations which is dependent on the substrate tempe rature. The In mole fraction drops almost linearly with increasing substrat e temperature above 580 degrees C, with a dropping rate of 0.08-0.13%/degre es C which is dependent on In/Ga beam equivalent pressure (BEP) ratio. The In mole fraction drops almost linearly with decreasing substrate temperatur e below 500 degrees C. The decrease below 500 degrees C reported here is ob served for the first time. (C) 1999 Elsevier Science B.V. All rights reserv ed.