Narrow gap III-V materials for infrared photodiodes and thermophotovoltaic cells

Abstract

The paper describes liquid phase epitaxial growth and characterization of the GaSb- and InAs-related materials for the photodiodes and thermophotovoltaic applications. It was shown that doping of the melt with holmium results in obtaining the high purity GaInAsSb and InAs layers. The passivation with the 1 M Na2S aqueous solution makes it possible to prepare flat growth surfaces of GaSb(1 0 0) and InAs(1 0 0) substrates after annealing. A reproducible technique has been developed for fabrication of the high-efficiency GaInAsSb/GaAlAsSb and InAs/InAsSbP photodiodes with the long-wavelength photosensitivity edge of 2.4 and 3.8 mu m, respectively. Room temperature detectivity in the spectral peak reaches D* = (0.8-1.0) x 10(11) W-1 cm Hz(1/2) for the GaInAsSb/GaAlAsSb photodiodes and D* = (3.0-5.0) x 109 W-1 cm Hz(1/2) for the InAs/InAsSbP devices. We have adapted the technology for thermophotovoltaic cells operating at an emitter temperature of 1000-1700 degrees