Growth temperature dependent band alignment at the Ga0.51In0.49P to GaAs heterointerfaces

Abstract

Photoluminescence analysis of Ga0.51In0.49P/GaAs single-quantum well structures grown by metal-organic vapor-phase epitaxy in the temperature range from 570 to 720 °C have been carried out. Besides the GaAs band-edge emissions, all SQW samples studied here exhibit a dominant long-wavelength peak, which is attributed to the spatially indirect transition due to the type-II band alignment of Ga0.51In0.49P/GaAs heterojunctions. The energy of the type-II PL emission has been found to depend strongly on the growth temperature indicating the strong influence of the growth temperature on the band alignment. The shifts of the type-II PL emission have been used to estimate the growth temperature dependent conduction and valence band discontinuity of the Ga0.51In0.49P/GaAs heterojunction. X-ray diffraction measurements and simulations using the dynamical theory were carried out to study the influence of the growth temperature on the unintended interfacial layers.