Grating coupled enhancement of light emission from IR Light emitting diode devices

We report here the electroluminescence in the range of 3-4.5 mu m and 6-10 mu m from Sb-based type II interband quantum cascade structure LED devices. We measured the light emission from the top surface of the device with different grating structures. We used different etch depths for the grating formation. The light-current-voltage (LIV) characteristics measured at both room and cryogenic temperatures show that the device with 45 degree angle grating and 1.0 mu m deep etch onto the GaSb surface has the highest emission power.