FABRY-PEROT REFLECTANCE MODULATOR FOR 1.3 MU-M FROM (INALGA)AS MATERIALS GROWN AT LOW-TEMPERATURE

We report the first all-semiconductor Fabry-Perot-cavity reflectance modulators operating at wavelengths of 1.32-1.33 mum. These devices were grown on a GaAs substrate using an intermediate, linearly graded InGaAs buffer layer terminating in an In0.33Ga0.67As layer. The Bragg reflector stacks of the Fabry-Perot structure are composed of InGaAs and InAlAs layers lattice matched to the buffer, and the active cavity region is an In0.4Ga0.6As/In0.26Al0.35Ga0.39As strained-layer superlattice. The key to obtaining device-quality material was low temperature growth (approximately 400-degrees-C) of the entire structure. For a device with a 0.38-mum-thick active region and a 4 dB insertion loss, we obtained a contrast ratio of approximately 3:1 at 4 V bias.