Electrochemical and Solid-State Letters · 2012 · 38 citations · 18 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesThin FilmsCarrier TransportCurrent-voltage CharacteristicsMetal-oxide-semiconductor Field-effect TransistorsThin Film Electrical PropertiesThin-film MaterialsThin-film TransistorsBias Stress EffectsCarrier Transport MechanismsCharge TrappingCharge Trapping EffectsPlasma TreatmentThreshold VoltageTrap MechanismsTrapping Effects
We have investigated the dependency of alternating current (AC) stress duty ratio on the stability of indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs). As the duty ratio increases from 0.25 to 0.75, threshold voltage (VTH) shift under the AC gate bias stress was increased from 4.10 V to 5.01 V, without degradation of subthreshold slope and mobility. The dominant mechanism of VTH shift was considered the charge trapping and VTH shift along with time was well fitted to a stretched-exponential model. The VTH shift was suppressed with a reduction of trap density by employing N2O plasma treatment on the gate insulator.
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