Electroluminescence of Sn O 2 ∕ p - Si heterojunction

Polycrystalline Sn O 2 film of tetragonal rutile structure with an optical band gap of 3.9 eV was formed by oxidation process at 1000 ° C on electron beam evaporation deposited Sn film. Room temperature electroluminescence from the Sn O 2 ∕ p - Si heterojunction was observed at 590 nm when the device was under sufficient forward bias with the positive voltage applied on the p - Si substrate. It is proposed that the electrons in the conduction band of Sn O 2 relax to defect states that resulted from the dangling bonds at the surface of the small Sn O 2 grains and then radiatively recombine with the holes in the valence band.