A Plasma NH3 Process to Improve the Reliability of 0.35μm P+ Poly-Gate Nitrided Oxide P-MOSFET's

For advanced 0.35 μm CMOS technologies, the performances and hot-carrier reliability of P+ poly-gate P-MOSFET's are investigated with DC and AC experiments. It is shown that devices with an optimized plasma NH
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nitrided gate-oxide have good characteristics which lead to a higher hot-carrier resistance in nitrided (8nm) gate-oxides than in pure oxides. AC Pass transistor degradations show competing damage mechanisms where donor-type interface trap generation and electron detrapping have much more effects than the usual electron-trapping-induced channel shortening. These distinct degradation effects are less significant in nitrided oxide p-MOSFET's due to the lower amount of trapped charges and generated interface traps.