TiO2薄膜的硼掺杂对TiO2/p+-Si异质结器件电致发光的增强

Abstract

TiO2/p+-Si and TiO2∶B / p+-Si heterostructures were formed by sputtering TiO2 films and boron-doped TiO2( TiO2∶ B) films on heavily boron-doped silicon( p+-Si) substrates,respectively,followed by annealing at 600 ℃ in O2 ambient. In contrast with the TiO2/ p+-Si heterostructured devices,the TiO2∶ B / p+-Si counterpart exhibits markedly enhanced electroluminescence( EL). It is derived that the doped B atoms in TiO2∶ B films enter into the interstitial sites of TiO2 lattice after annealing at high temperature,which introduces excess oxygen vacancies. The increase of the concentration of oxygen vacancies due to B-doping leads to the enhancement of EL from the TiO2∶ B / p+-Si heterostructured devices because oxygen vacancies are the light-emitting centers of the TiO2/p+-Si heterostructured devices.