High Performance MWIR/LWIR LED Wafers on Si Substrates for Scene Projectors

The state-of-the-art in infrared scene projection uses micro-machined resistor arrays. These arrays have limited frame-rate, dynamic range, and can be cost prohibitive as the array size increases. Alternative technologies are required. The most promising is infrared light emitting diodes (IR LED) based on InAs/GaSb type-II superlattices (T2SL) or W-Quantum Wells, with the ability to tune the bandgap from ~ 3 to 20 microns. Phase I and recent results of T2SL-LED performance on lattice mismatched GaAs substrates shows that defect processes are not significantly detrimental to performance under the high injection conditions of high power LEDs, and that the substrate thermal conductivity is important. These results suggest that translation of the T2SL to the use of Si substrates will be even more beneficial. In this Phase II STTR we will develop the growth technology and wafer supply chain - capability for development and manufacture of these IR LEDs on Si and GaAs substrates. The program combines significant national talent and know-how to addressing growth technology and domestic sourced IR LED supply chain needs that involves Amethyst Research, University of Texas at Austin, Texas State University, University of New Mexico and Naval Research Laboratory.