Hot-electron immunity of SiO/sub 2/ dielectrics with fluorine incorporation

The effect of fluorine incorporation in the gate oxide on the NMOSFET hot-electron immunity is examined. Fluorine is implanted in the polysilicon gate and diffused into the gate oxide. The hot-electron immunity of NMOSFETs is shown to increase with increasing fluorine doses. Measurement of device lifetime against substrate current shows that higher doses of fluorine lead to a change in the immunity to interface trap generation. Based on the results of Auger measurements, this has been correlated with a fluorine deficient layer near the interface.<
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