High reflectivity symmetrically strained ZnxCdyMg1-x-ySe-based distributedBragg reflectors for current injection devices

Distributed Bragg reflectors (DBRs) with different numbers of periods were grown by molecular beam epitaxy from ZnxCdyMg1-x-ySe-based materials on InP substrates. The alternating ZnCdSe/ZnCdMgSe layers were symmetrically stra ined to the InP substrate greatly simplifying the growth process and increa sing the uniformity. High crystalline quality was also achieved in these st ructures. A maximum reflectivity of 99% was obtained for a DBR with 24 peri ods. Chlorine doped (n-type) DBRs were grown and their electrical and optic al properties were investigated. Electrochemical capacitance-voltage profil ing indicated that the doping concentrations of the ZnCdSe and ZnCdMgSe lay ers were 4 X 10(18) and 2 X 10(18) cm(-3), respectively. The reflectivity o f the doped DBR structures was comparable to that of the undoped ones. (C) 2001 American Vacuum Society.