High resolution X-ray diffraction and transmission electron microscopy investigation on As and P incorporation in MOCVD and CBE grown In(GaAs)P/InP 'false' multi quantum wells

Abstract

The problem of interface sharpness, both for composition and planarity, is important in InGaAs(P)/InP multiple quantum wells (MQWs) based optoelectronic devices. Composition variations arise due to the need to protect the interfaces from thermal degradation with a group V atom flux during growth interruptions and their effect depends on the growth technique. To understand the influence of such compositional variations on both InP/InGaAs and InGaAs/InP interfaces separately, false MQWs (FMQWs) were intentionally grown. The FMQWs result from the incorporation of protecting group V species different to that present in the growing layer during the periods of growth interruptions. The effects of different atoms of group V (As,P) on interface roughness and compositional changes in InP(As)/InP and InGaAs(P)/InGaAs FMQWs grown at different growth temperatures and with different growth interruption times by chemical beam epitaxy and metal organic chemical vapor deposition have been studied. This work has been performed by combining high resolution transmission electron microscopy and high resolution X-ray diffraction techniques.<>