Cubic GaN light emitting diode grown by metalorganic vapor-phase epitaxy

We studied Si and Mg doping characteristics in cubic GaN and fabricated a l ight emitting diode of cubic GaN on a GaAs substrate by metalorganic vapor- phase epitaxy. The diode structure consisted of undoped and Mg-doped GaN st acking layers deposited on Si-doped GaN and AlGaN layers. The electron-beam -induced-current signal and current injection characteristics of this diode structure were measured. There was a peak at the interface between the Mg- doped and undoped GaN in the electron-beam-induced-current signal. This sho ws successful growth of the p-n junction. Light emitting operation was achi eved by currents injected through the conducting GaAs substrate of this dio de at room temperature. We observed electroluminescence below the bandgap e nergy of cubic GaN with a peak at 2.6 eV.