Formation of metal nitride oxide semiconductor (MNOS) by ion implantation of oxygen through a silicon nitride layer

摘要

A layer of silicon nitride (Si3N4) is deposited on a silicon substrate. A mask provided with windows representing device structures is then formed over the silicon nitride layer. Oxygen is then implanted through the window portion of the silicon nitride layer into the Si3N4/Si interface region to form a tunneling insulator interface layer of silicon dioxide (SiO2). The final structure is heat treated and then has the form Si3N4/SiO2/Si. It can be made into a metal nitride oxide semiconductor (MNOS) field effect transistor device by conventional diffusion, ion implant and metallization processes.