Ga/sub x/In/sub 1-x/As thermophotovoltaic converters

Preliminary research into the development of single-junction Ga/sub x/In/sub 1-x/As thermophotovoltaic (TPV) power converters is reviewed. The devices structures are grown epitaxially on single-crystal InP substrates. Converter band gaps of 0.50 -0.74 eV have been considered in accordance with modeling calculations. A 1-sun, AMO efficiency of 12.8% is reported for a lattice-matched, 0.74-eV converter. Converters with lower band gaps are fabricated using lattice-mismatched, compositionally graded structures. Functional TPV converters with good performance characteristics have been demonstrated for band gaps as low as 0.5 eV.