MOLECULAR-BEAM EPITAXY-GROWN ALASSB GAASSB DISTRIBUTED-BRAGG-REFLECTOR ON INP SUBSTRATE OPERATING NEAR 1.55-MU-M/

Surface normal optoelectronic devices operating in the 1.3-1.5 mum wav elength range require distributed Bragg reflectors (DBRs) with a pract ical number (less-than-or-equal-to 50) of mirror layers. This requirem ent implies a large refractive index difference between the mirror lay ers, which is difficult to achieve in the traditionally used phosphide compounds. For the first time, an AlAsSb/GaAsSb DBR grown nominally l attice matched to an InP substrate by molecular bearn epitaxy is demon strated. Reflectivity measurements indicate a stop band centered at 1. 53 mum, which is well fitted by these theoretical predictions. Atomic force microscopy and transmission electron microscopy indicate reasona ble crystal quality with some defects due to an unintentional lattice mismatch to the substrate.