EFFECTS OF THE OXIDATION PROCESS ON THE ELECTRICAL CHARACTERISTICS OFOXIDIZED NITRIDE FILMS

The effects of the oxidation process on the electrical characteristics of metal-oxide-semiconductor (MOS) capacitors were studied. It was fo und that electrical and time dependent dielectric breakdown (TDDB) cha racteristics are improved for the MOS capacitor with a wet oxidized ni tride film over the N2O oxidized nitride film. The depth profile of th e oxidized nitride film is also studied by Auger electron spectroscopy . It is observed that from the top surface of an oxidized nitride film of about 2 nm (nitride film oxidized in the wet oxidation process or in N2O ambient by rapid thermal processing), the level of oxygen is th e same but, compared to a N2O oxidized nitride film, the level of nitr ogen is greater in a wet oxidized nitride film. The improvement of the electrical and TDDB characteristics of the wet oxidized nitride film over the N2O oxidized nitride can be thought due to the increased amou nt of nitrogen from the top surface to a depth of nearly 2 nm of the o xidize nitride films. (C) 1996 American Institute of Physics.