Largely variable electroluminescence efficiency with current and temperature in a blue (In, Ga)N multiple-quantum-well diode

Electroluminescence (EL) efficiency of a blue In0.3Ga0.7N multiple-quantum-well diode has been investigated as a function of current between 0.001 and 20 mA at various temperatures (20-300 K). The low-temperature EL quenching previously observed below 100 K at a driving current of 20 mA does not occur at 0.001 mA and is found to be strongly dependent on the current level. Largely variable temperature-dependent EL quantum efficiency with current suggests that the injected carrier capture efficiency by radiative recombination centers plays a decisive role for determination of the EL efficiency under the forward bias condition. (C) 2007 American Institute of Physics.