INTERFACE EFFECTS ON THE PHOTOLUMINESCENCE OF GAAS GAINP QUANTUM-WELLS/

The influence of indium surface segregation, As-P exchange at the inte rfaces and residual incorporation of As and P on the photoluminescence properties of GaAs/GaInP quantum wells, is investigated both theoreti cally and experimentally. It is shown that these effects may lead to a n important energy shift or compensate each other depending on growth conditions. As a consequence the exploitation of photoluminescence spe ctra in such heterostructures have to be carefully carried out. Four s amples have been especially designed to study, in addition to indium s egregation, the As-P exchange at the GaAs on GaInP interface. Their lo w temperature photoluminescence study illustrates the complex behaviou rs observed in this material system. Photoluminescence spectra are sho wn to be very sensitive to the interface chemistry, in particular As-P exchange.