QUANTUM-WELL STRUCTURES OF INALP/INGAP GROWN BY GAS-SOURCE MOLECULAR-BEAM EPITAXY

Both single quantum-well (SQW) and multiple quantum-well (MQW) structures have been produced using the technique of gas-source molecular-beam epitaxy to grow the two wide band-gap ternary alloys, InAlP and InGaP. SQWs as narrow as two monolayers observed by bright field transmission electron microscopy were found to be laterally uniform with abrupt InAlP/InGaP interfaces. Photoluminescence of SQWs of differing thickness produced a larger quantum confinement energy shift than expected, with emission at 570 nm for an InGaP well of 3.0 nm in thickness. The number and amplitude of peaks detected in double-crystal x-ray diffraction (DCXR) measurements of the MQW samples matched, to within the limit of the dynamic range of the DCXR system, the peaks calculated in a periodic two-layer dynamical simulation of the x-ray rocking curve.