Low-voltage GaN : Er green electroluminescent devices

Green light emission has been measured from Er-doped GaN electroluminescent devices (ELDs) at an applied bias as low as 5 V. The GaN-Er ELDs were grow n by solid source molecular beam epitaxy on Si (111) substrates. We have ac hieved this low-voltage operation (ten-fold reduction in optical turn-on vo ltage) by using heavily doped (similar to 0.01 Omega cm) Si substrates and by decreasing the GaN-Er layer thickness to several hundred nanometers. A s imple device model is presented for the indium tin oxide/GaN-Er/Si/Al ELD. This work demonstrates the voltage excitation efficiency of Er3+ luminescen t centers and the compatibility of GaN rare earth-doped ELDs with low-volta ge drive circuitry. (C) 2000 American Institute of Physics. [S0003- 6951(00 )01511-4].