Abstract

The Ga_xIn_1−xAs_yP_1−y lattice-matched quaternary alloy system is particularly promising both for the development of integrated optical circuits realized on InP substrates, and the utilization of these circuits in fiber optic communication systems in the 1.30-1.35/um low-loss, zero dispersion spectral window. The complete optical communication system is composed of an emitter, transmission medium and receiver. Although considerable attention has been paid to the development of new luminescent sources¹ and optical waveguides² near the 1.3/um regime of the optical spectrum, there has been no equivalent development of a detector suitable for optical signal processing in this spectral region. In this paper we present the Ga_0.47In_0.53As homojunction avalanche photodiode, the first photodiode fully integrable with sources and waveguides on InP substrates. With a direct bandgap at 1.7 um, this photodiode is sensitive to radiation from nearly any proposed Ga_xIn_1−xAs_yP_1−y luminescent device which can be grown lattice-matched on InP. Operating at room-temperature, these photo-detectors have a dark-current level three orders of magnitude less than that of germanium photodiodes (which show a similar spectral response, but which cannot in any case be grown on InP).

© 1978 Optical Society of America