Article ID Journal Published Year Pages File Type
1795303 Journal of Crystal Growth 2007 5 Pages PDF
Abstract

Quaternary InAsxPySb1−x−y alloys nearly lattice-matched to InAs substrates have been successfully grown by gas source molecular beam epitaxy (GSMBE) with the composition covering the immiscibility region. Through high resolution X-ray diffractometry, we observed the compositional inhomogeneity in these alloys. Enhancement in the As incorporation in the growth can not only narrow the inhomogeneous broadening but also improve the surface morphology. Carrier recombination in band-tail states caused by the compositional inhomogeneity is attributed to the low-temperature PL emission in these samples. The PL peak energy is thus lower than the predicted band-gap energy. The energy discrepancy can be as large as 0.26 eV, and decreases dramatically to 36 meV as the As mole fraction increases to 0.681. For the high As mole fraction sample, band-to-band recombination is observed as the temperature is higher than 100 K.

Related Topics
Physical Sciences and Engineering Physics and Astronomy Condensed Matter Physics
Authors
, , , , , ,