Low-temperature study of current and electroluminescence in InGaN/AlGaN/GaN double-heterostructure blue light-emitting diodes

Electrical and optical properties of Nichia double-heterostructure blue light-emitting diodes, with In0.06Ga0.94N:Zn, Si active layer, are investigated over a wide temperature range from 10 to 300 K. Current-voltage characteristics have complex character and suggest the involvement of various tunneling mechanisms. At small voltages (and currents),the peak wavelength of the optical emission shifts with the applied bias across a large spectral range from 539 nm (2.3 eV) up to 443 nm (2.8 eV). Light emission takes place even at the lowest temperatures, indicating that a complete carrier freeze-out does not occur. (C) 1996 American Institute of Physics.