Optical signature of atomic ordering in In0.53Ga0.47As/InP: photoluminescence properties and IR response

Lattice-matched InGaAs/InP epilayers, grown by metal-organic vapor phase epitaxy, were investigated by PL spectroscopy and FT-IR to analyze the atomic ordering. Owing to the formation of the InGaAs/InP interface it was shown that growth conditions parameters such as growth temperature or arsenic precursor influence the development of atomic ordering. Low temperature optical properties of samples grown at 570-600 °C with trimethylarsenic (TMAs) and arsine are compared. A blue-shift of the PL peak position with increasing the excitation density is observed with a band gap reduction of 70-80 meV for TMAs-grown epilayers. Also a change in the IR absorption spectrum at 600-700 cm 1 is seen. Ordering is enhanced for TMAs-grown epilayers up to 600 °C growth temperature while it is not observed for arsine-grown epitaxial layers at the same growth temperature.