Ga1-xInxAs photodetectors for 1.3 micron PIN-FET receiver

Current interest in fibre optic systems designed to operate in the 1.2-1.4 micron range has stimulated the development of III-V alloy photodetectors optimised for longer wavelength applications. In order to meet this requirement we are developing Ga1-xInxAs photodetectors suitable for use in a hybrid PIN-FET receiver module. The devices are fabricated in VPE grown epi-layers with mesa isolation of the grown-in junctions. Particular attention has been paid to minimising the doping level in the constant composition n-layer to obtain low junction capacitance. A remote bonding-pad configuration is utilized to reduce the effects of bonding degradation. Photodiodes exhibiting high quantum efficiency at 1.3 microns with relatively low dark currents have been fabricated to date.