512x512 array of dual-color InAs/GaSb superlattice light-emitting diodes

InAs/GaSb superlattice light-emitting diodes are a promising technology for progressing the state-of-the art infrared scene projectors. By targeting a specific band of interest, they are able to achieve apparent temperatures greater than that of conventional resistor arrays and settling times on the order of nanoseconds. We report the fabrication of a dual-color infrared InAs/GaSb superlattice light-emitting diode array for operation in the mid-wave infrared. By stacking two superlattice structures back-to-back with a conductive layer separating them, independently operable, dual-color, cascaded InAs/GaSb superlattice light-emitting diodes were grown via molecular beam epitaxy on (100) GaSb substrates. At 77K, the emitted wavelengths are in the 3.2-4.2 mu m and 4.2-5.2 mu m range, with peak wavelengths at 3.81 mu m and 4.72 mu m. Using photolithography and wet etching, a 512x512 array of 48 mu m-pitch pixels were fabricated and hybridized to a silicon readin integrated circuit. Test arrays with an 8x8 matrix of pixels demonstrated greater than 2 W/cm(2).sr for the 4.7 mu m emitter and greater than 5W/cm(2).sr for the 3.8 mu m emitter; the lower radiance in the long-wave emitter is due to a small active region volume left after fabrication. These respectively correspond to apparent temperatures greater than 1400K and 2000K in the 3-5 mu m band including fill factor.