Some evidences of ordering in InGaP layers grown by liquid phase epitaxy

We make a comparative study of the optical and structural characteristics of two InxGa1−xP (x≈0.5) films nearly lattice matched to GaAs, here referred to as sample S1 and sample S2. The films were grown by liquid phase epitaxy (LPE). Photoluminescence (PL) measurements were performed in a wide temperature and exciting power density range for different polarizations (parallel to the [0 1 1] and [0 1̄ 1] directions) of the emitted radiation. Observations suggest that the InxGa1−xP layer in one of the samples has the usual characteristics commonly obtained in an LPE grown material, while in the other sample, an anomalous growth took place. Our experimental observations show differences in the layer thickness, the surface morphology, as well as in the structural and optical characteristics such as the 4 K PL energy peak position.