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 blu e light-emitting diodes, with In0.06Ga0.94N:Zn, Si active layer, are i nvestigated over a wide temperature range from 10 to 300 K. Current-vo ltage characteristics have complex character and suggest the involveme nt of various tunneling mechanisms. At small voltages (and currents),t he peak wavelength of the optical emission shifts with the applied bia s 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, indi cating that a complete carrier freeze-out does not occur. (C) 1996 Ame rican Institute of Physics.