Blue Electroluminescence From Metal/Oxide/6H-SiC Tunneling Diodes

The tunneling current of Pt/oxide/n-6H-SiC tunneling diodes was used for electroluminescence (EL). The negative gate bias can inject electrons from Pt to n-SiC and leads to a radiative donor-acceptor pair (DAP) transition. The blue EL at room temperature is observed at negative gate bias, and the intensity increases with increasing drive current. The DAP transition is enhanced by the electric field due to carrier tunneling. Thus, strong luminescence is observed at negative (inversion) bias, while no luminescence is observed at positive (accumulation) bias.