Structural and optical properties of In x Ga1−x As strained layers grown on GaAs substrates by MOVPE.

Abstract: In x Ga1−x As/GaAs pseudomorphic structures were grown by metalorganic vapor phase epitaxy. Reciprocal space mapping were recorded in the vicinity of (004) and (115) nodes using high resolution X-ray diffraction (HRXRD) in order to determine strain tensor components, indium compositions and thicknesses of alloys. Near-infrared photoluminescence (PL) was performed at 10K. The impact of strain on PL response was revealed by peak energy positions and line width. In addition, valence-band splitting (VBS) and the shift of the heavy-hole were measured. Besides, photoreflectance (PR) at room temperature was useful to establish experimentally the dependence of VBS and band energy shifts (E 0 and E 0+∆ 0) on elastic strain due to lattice mismatches. Other parameters such as the internal electric-field and the electro-optical energy were determined from Franz–Keldysh oscillations analysis. Good correlation between the results obtained from all investigated techniques and theoretical predictions was confirmed. [Copyright &y& Elsevier]