IEEE Electron Device Letters · 2008 · 11 citations · 23 references
EngineeringElectrical EngineeringPhysicsMicroelectronicsSemiconductor DevicesSemiconductor MaterialsHigh-frequency Semiconductor DevicesMetal-oxide-semiconductor Field-effect TransistorsSemiconductor DefectsSemiconductor PhysicsSemiconductor ReliabilityWide-bandgap Semiconductor DevicesBias Temperature InstabilityGate Oxide InterfacesGate Oxide Thickness EffectsN-type Oxide SemiconductorsNegative Bias Temperature Instability
The dynamic negative-bias-temperature-instability- induced threshold-voltage shift |DeltaV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> | of p-MOSFETs employing ultrathin decoupled-plasma- and thermal-nitrided SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gate dielectrics is studied as a function of gate frequency. The dependence of |DeltaV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> | on the gate frequency under unipolar stress is observed to become weaker for p-MOSFETs having higher nitrogen concentrations in the gate oxide. Evidence shows that reduced frequency dependence results from a greater lock-in of |DeltaV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> |, mainly due to an increased generation of recovery-resistant deep-level hole traps in the heavily nitrided gate p-MOSFET.
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