Molecular-beam-epitaxy-grown ZnSe/ZnTe high-reflectivity distributed Bragg reflectors

摘要

A series of distributed Bragg reflectors (DBRs) with differentnumbers of periods were fabricated by molecular beam epitaxy usingZnSe and ZnTe layers grown on GaAs substrates. The ZnSe/ZnTecombination manifests over 7 lattice mismatch, which leads to adeterioration of multilayer stacks with large numbers of periods.However, even with the deposition of only eight periods we haveobtained ZnSe/ZnTe DBR structures which yield reflectivities inexcess of 85. Furthermore, these DBRs show wide stop-bands-anadditional advantage of using the ZnSe/ZnTe combination. By varyingthe number of periods in these structures, we have also studied howthe reflectivity changes with the number of periods in this materialscombination. The reflectivity obtained by depositing four ZnSe/ZnTeperiods was 66.5, while by depositing l5 periods we obtained 91reflectivity.