Photoluminescence studies of As-P exchange in GaAs/GaInP2 quantum wells grown by chemical beam epitaxy

Group V element exchange during the growth of GaAs/Ga0.51In0.49P quantum we lls (QWs) by chemical beam epitaxy is investigated by photoluminescence (PL ) experiments as a function of temperature from 4 to 300 Ii. In order to st udy the As-P exchange at the direct interface of the GaAs QW, the GaInP2 su rface is exposed to a cracked AsH3 how during various times. The QW free ex citon energy is deduced at 4 Ii by fitting the temperature dependence of th e PL energy with the classical expression E(T) = E-0 - a[1 + 2/{exp(theta/T ) - 1}]. The calculation of the E1HH1 energies are carried out by taking in to account the following phenomena which affect the QW structure: indium se gregation, As-P exchange and As and P residual incorporations. It is found that As-P exchange rate decreases with the increase of the cracked AsH3 exp osure time. (C) 1998 Elsevier Science S.A. All rights reserved.