The structures of Au/Si-rich SiO2/p-Si and Au/Si-rich SiO2/n+-Si have been fabricated and their electroluminescence characteristics have comparatively been studied. For the Au/Si-rich SiO2/p-Si structure, when the forward bias is more than 4V, red light is emitted, while under the reverse bias, no light is observed. For Au/Si-rich SiO2/n+-Si structure, it does not emit light under the forward bias, but it emits red light when the reverse bias is greater than 3.5V. The mechanism for electroluminescence from the Au/Si-rich SiO2/n+-Si structure is disscussed.