DIFFERENTIAL REFLECTANCE SPECTROSCOPY OF GAAS GAALAS AT ELEVATED-TEMPERATURES/

Differential reflectance (DR), a contactless optical modulation techni que, has been used to study GaAs/AlGaAs quantum wells and bulk GaAs, o ver a wide temperature range (77<T<600 K), The objective of this study was to demonstrate that DR, unlike most optical modulation spectrosco pies, can be effectively and effortlessly used at elevated temperature s, and, thus, provide considerable potential for in situ monitoring. W e have used DR to measure the temperature dependence of several critic al points of GaAs and AlxGa1-xAs (x=0.31). (C) American Institute of P hysics.