The primary objective of this project is to improve the light extraction efficiency of large-format mid-wave infrared (MWIR) and long-wave infrared (LWIR) superlattice light emitting diode (SLED) arrays for infrared scene projector applications. While SLED technologies have shown great promise for scene projectors, their full potential has yet to be realized due to both electrical and optical inefficiencies. This project seeks to increase the optical efficiency of MWIR SLEDs through photonic crystal structures. Phase 2 builds upon Phase 1 work, in which 2D photonic crystal patterned interfaces were designed to assist with light extraction from SLEDs, and photonic crystal fabrication in GaSb was developed and demonstrated. In Phase 2, 2D photonic crystal design will be extended by considering alternate shapes, compositions, and configurations of individual scatterers, and the best 2D designs will be tested in actual SLEDs devices. Additionally, resonant cavity SLEDsutilizing 1D photonic crystal mirrors, or distributed Bragg reflectorswill also be designed and tested for enhanced light extraction. These will be integrated with 2D photonic crystals for maximum light extraction. Scalability of photonic crystals to larger areas (1 cm2) shall be developed and demonstrated.
