Method of manufacturing an oxide-nitride-oxide (ONO) dielectric for SONOS-type devices

A method of forming oxide-nitride-oxide (ONO) dielectric of a SONOS-type nonvolatile storage device is disclosed. According to a first embodiment, a method may include the steps of forming a tunneling dielectric (step ), forming a charge storing dielectric (step ), and forming a top insulating layer (step ) all in the same wafer processing tool. According to various aspects of the embodiments, all layers of an ONO dielectric of a SONOS-type device may be formed in the same general temperature range. Further, a tunneling dielectric may include a tunnel oxide formed with a long, low pressure oxidation, and a top insulating layer may include silicon dioxide formed with a preheated source gas.