InGaN/GaN multi-quantum-well planar metal-semiconductor-metal light-emitting diodes

Planar metal-semiconductor-metal light-emitting diodes with InGaN/GaN multi-quantum-wells (MQWs) as the active layer have been demonstrated for the first time. The diodes with interdigitated Schottky electrodes fabricated on p-GaN contact layer exhibit symmetrical current-voltage characteristic with a turn-on voltage of ~ 13 V at 20 mA. The violet light emission centred at 408 nm is generated by radiative recombination taking place in the MQWs. The evolution of light output power against injection current reveals an enhanced carrier collecting efficiency of the active MQWs at higher injection current level, which follows a P prop I^2.8 trend below 30 mA.