Evidence of phosphorus incorporation into InGaAs/InP epilayersafter thermal annealing

We report on Raman scattering measurements on annealed In0.53Ga0.47As/InP layers that reveal the outdiffusion of phosphorus from, the substrate and its, possible incorporation in substitutional positions in. the In0.53Ga0.47As lattice. Raman signal associated with InP-like modes was detected in the annealed samples. The effect is also observed in samples where the substrate was protected by a SiNx:H capping and were annealed in arsenic atmosphere, thus ruling out the possibility of a surface contamination by atmospheric phosphorus evaporated from the InP substrate.. Protruding regions. of a few microns were observed on the surface, which were identified as misoriented In1-xGaP and InP crystals by means of micro-Raman measurements. (C) 2003 American Institute of Physics.