Antimonide-based devices for thermophotovoltaic applications

Thermophotovoltaic (TPV) devices have been fabricated using ternary and qua ternary layers grown by metalorganic vapor phase epitaxy. (MOVPE) on GaSb s ubstrates, GaInSb ternary devices were grown with buffer layers to accommod ate the lattice mismatch, and GaInAsSb quaternary devices were grown with L attice-matched compositions. Improved devices are obtained when optical abs orption occurs in the p-layer due to the longer minority carrier diffusion length. Thick emitter p/n devices are limited by surface recombination, wit h highest quantum efficiency and lowest dark current being achieved with ep itaxially grown surface passivation layers on lattice-matched MOVPE quatern aries, Thin emitter/thick base, n/p devices are very promising since surfac e passivation is less critical than for p-emitter devices.