Electroluminescence from Indium Tin Oxide Film/Nanoscale Si Oxide/p-Si Structure

After an Si oxide layer of 3nm thickness had been grown by using magnetron sputtering on a p-type Si (100) substrate, an indium tin oxide (ITO) film was deposited onto the Si oxide layer by using electron beam deposition. Electroluminescence (EL) from such an ITO/Si oxide/p-type Si structure was measured under a forward bias of 5V or more. Its EL power efficiency is about eight times as large as that of a semitransparent Au/Si oxide (3nm)/p-Si structure. The experimental results indicate that the greater EL power efficiency is due not only to the higher optical transparency of the ITO film compared with Au film in a range of 300 to 900nm, but also to some new luminescence centers introduced in the Si oxide layer during the ITO deposition process.