Visible electroluminescence was detected in Ag/SiO2/n-type Si structures. The electroluminescence occurred only under reverse-bias conditions, when the Ag electrode was negative. A forward bias was required for p-type samples. The intensity of the electroluminescence was proportional to the diode current, and its spectrum peaked at 620 to 640nm. It was suggested that the electroluminescence in these structures corresponded to the 1.9eV photoluminescence emission from silica glass. It was tentatively attributed to non-bridging O hole centers.

Visible Electroluminescence from Native SiO2 on n-Type Si Substrates. J.Yuan, D.Haneman: Journal of Applied Physics, 1999, 86[4], 2358-60