Gas source molecular beam epitaxy growth of TlInP for new infrared optical devices

Abstract

Gas source molecular beam epitaxy growth of TlInP (thallium indium phosphide) on (100) InP substrate is described. TlInP is an important constituent material of newly proposed novel infrared optical device material, TlInGaP, which can be lattice-matched to InP. Reflection high-energy electron diffraction reveals the (2×2), (2×4), and (4×2) streak patterns corresponding to the P-excess, P-stabilized and group-III rich surfaces, respectively. However, facet pattern emerges in the low temperature (380 °C) growth. This pattern is consistent with the scanning electron microscopy image; hatched pattern along the [011] direction, which is caused by insufficient migration of group III adatoms on the surface. Double crystal x-ray diffraction rocking curves for TlP on InP and TlInP on InP samples clearly show the peak from TlP and TlInP as well as that from InP substrate. The peak position is changed with Tl/In flux ratio. Photoluminescence emission is observed for TlInP grown on InP.