METHOD FOR NON-THERMALLY NITRIDED GATE FORMATION FOR HIGH VOLTAGE DEVICES

摘要

A method is provided for non-thermally nitrided gate formation of high voltage transistor devices. The non-thermally nitrided gate formation is useful in the formation of dual thickness gate dielectric structures. The non-thermally nitrided gate formation comprises nitridation to introduce nitrogen atoms into the gate dielectric layer of the high voltage transistor devices to mitigate leakage associated with the high voltage transistor devices. The nitridation of the gate dielectric layer damages the surface of the gate dielectric layer. The damaged surface of the gate dielectric layer is removed by a relatively low temperature re-oxidation process. The low temperature re-oxidation process minimizes nitrogen loss during a subsequent photoresist stripping process and mitigates film densification, such that the structure can be readily etched by standard etching chemicals in subsequent processing.