InAsSb/GaSb Infrared Light-Emitting Diodes (LED's)

AstroPower proposes to develop intense, mass-producible, low-cost 4 to 5 micron light-emitting diodes (LED's) using liquid-phase heteroepitaxy of lattice-matched InAsSb on GaSb substrates. The brightest visible LEDs (Ultrabrights) currently available are being produced commercially by the liquid phase heteroepitaxy process using materials with bandgaps in the appropriate visible range for the particular color desired and with matched lattice parameters. Liquid phase epitaxy has routinely provided quality LED and laser devices with the highest electrical-to-optical energy conversion efficiency. Furthermore, the optical design of the proposed IR LED is expected to be enhanced by special reflector and optical design considerations currently under development at AstroPower. This program will produce long life light sources of high solid-state quality -- quality not subject to the poor reliability and fragility of incandescent bulbs. Feasibility of this approach will be domonstrated by deliverable hardware by the end of the Phase I program.