Optical and structural properties of strained InAlAs/InAsxP1-x multi-quantum wells grown by solid source molecular beam epitaxy

We report on the optical and structural properties of strained InAlAs/InAsxP1-x heterostructures grown by solid source molecular beam epitaxy. The incorporation of As-4 into strained InAsP has been studied using x-ray diffraction and photoluminscence measurements. We find that the incorporation of As decreases as x in the InAsxP1-x increases due, presumably, to increased strain. In addition, we have examined the effect of interface growth conditions and barrier material on the quantum well properties. The 4.2 K photoluminescence spectra of InAlAs/InAsP multi-quantum wells grown with different As and P flux switching conditions at the interfaces were compared with that of higher quality InP/InAsP multi-quantum wells. This comparison shows that the interface quality of InAlAs/InAsP multi-quantum wells is highly dependent on the switching conditions at the interfaces, especially the exposure time of InAsP surface to an As-4 overpressure. This sensitivity is due to the As-P exchange reaction at the interfaces of InAlAs/InAsP. (C) 1999 American Institute of Physics. [S0021-8979(99)08717-4].