Lattice‐Matched GaInAsSb/AlGaAsSb/GaSb Materials for Thermophotovoltaic Devices

High‐performance GaInAsSb/AlGaAsSb/GaSb thermophotovoltaic (TPV) devices with quantum efficiency and fill factor near theoretical limits and open‐circuit voltage within about 15% of the limit are reported. This paper discusses detailed studies of GaInAsSb epitaxial growth, the microstructure, and minority carrier lifetime that have led to these results. For further improvements in TPV cell performance, device structures with either a distributed Bragg reflector or a back‐surface reflector are described.