Accession Number : ADA186858

Title :   Variable Band Gap Materials for Thermophotovoltaic Generators.

Descriptive Note : Final technical rept. 1 Apr 86-31 Aug 87,

Corporate Author : GA TECHNOLOGIES INC SAN DIEGO CA

Personal Author(s) : Woolf, Lawrence D ; Duggan, Dennis M ; Smith, Joe N , Jr

PDF Url : ADA186858

Report Date : Aug 1987

Pagination or Media Count : 66

Abstract : The objective of this research program was to design and develop direct band gap solar cells which would have high below band gap energy (infra-red (IR)) reflectivity for use in high efficiency thermophotovoltaic (TPV) energy conversion systems. Two types of customized GaAs cells were grown on intrinsic or semi-insulating GaAs substrates with either p-type GaAs or Al(.9) Ga (.1) As stop-etch layers. Holes were drilled through the substrate using a laser photochemical etch technique. Cells with high IR reflectivity and low series resistance were fabricated by drilling a hole which stopped at the contact layer of the cell with the Al(.9) Ga(.1) As stop-etch layer and then depositing gold in the hole and on the back surface. Measurements of these customized cells indicate that IR reflectivities in excess of 90%, corresponding to TPV efficiencies in excess of 35%, are feasible. Keywords include: Thermophotovoltaic energy conversion; GaAs solar cells; Photochemical etching; GaAs; Free carrier absorption; and Infra-Red reflectivity.

Descriptors :   *GALLIUM ARSENIDES, *P TYPE SEMICONDUCTORS, *SOLAR CELLS, *SUBSTRATES, ABSORPTION, CELLS, EFFICIENCY, ENERGY CONVERSION, ETCHING, HIGH RATE, INFRARED RADIATION, INSULATION, LASERS, LAYERS, PHOTOCHEMICAL REACTIONS, REFLECTIVITY, RESISTANCE, SURFACES

Subject Categories : Electric Power Production and Distribution
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE