Electroluminescence at high fields in silicon dioxide

Electroluminescence was observed in thermally grown silicon dioxide films at fields larger than 7 MV/cm. The samples had semitransparent aluminum electrodes. As breakdowns were nonshorting, observations could be extended to fields at which breakdowns occur. The light emission was found to be proportional to the leakage current and the spectrum had a cutoff for energies below 2.5 eV. The quantum efficiency, 10−5–10−4 photon/electron crossing 1000 Å of insulation, was polarity independent. The luminescence does not seem to be connected with breakdown, but perhaps with trapping processes.