Lightweight, light-trapped, thin GaAs solar cell for spacecraft applications: Progress and results update
Abstract
Progress is reported with respect to the development of ultra-lightweight, high performance, thin, light trapped GaAs solar cells for advanced space power systems. Conversion efficiencies of over 17.7% have been demonstrated for a 3 micron thick, 1 sq cm silicone bonded solar cell. This results in a specific power of over 1020 W/kg. Device parameters were 1.011 V open circuit voltage, 80% fill factor, and a short-circuit current density of 29.5 mA/sq cm . In addition to silicone bonding, the use of electrostatic bonding to attach the coverglass support to the front surface enables an ultra-thin, all back contact design that survives processing temperatures greater than 750 C. This also results in a 10% reduction of the cell weight for a potential specific power of 1270 W/kg. All back contact, ultra-thin, electrostatically bonded GaAs solar cell prototypes have been completed demonstrating an open circuit voltage of 1 volt for a cell base thickness of 1 micron with a 0.5 micron emitter. This technology will result in a revolutionary improvement in survivability, performance, and manufacturability of lightweight GaAs solar cell products for future Earth-orbiting science and space exploration missions. The thin, electrostatically bonded, all back contact GaAs device technology has multiple uses for specialty high performance solar cells and other optoelectronic devices.
- Publication:
-
14th Space Photovoltaic Research and Technology Conference (SPRAT 14)
- Pub Date:
- October 1995
- Bibcode:
- 1995sprt.nasa...24H
- Keywords:
-
- Electrostatic Bonding;
- Energy Conversion Efficiency;
- Gallium Arsenides;
- Metal Films;
- Prototypes;
- Silicones;
- Solar Cells;
- Spacecraft Power Supplies;
- Technology Utilization;
- Thin Films;
- Chemical Bonds;
- Current Density;
- Open Circuit Voltage;
- Short Circuit Currents;
- Thermionic Emitters;
- Weight Reduction;
- Energy Production and Conversion