Suppression of VT variability degradation induced by NBTI with RDF control

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variability degradation induced by negative bias temperature instability (NBTI) and its relation with random dopant fluctuation (RDF) are investigated by a special large-scale (16000 PFETs) device matrix array (DMA) TEG exclusive for NBTI variability measurements. It is clarified that V
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variability degradation is suppressed by reducing channel or halo dopant concentration. The suppression mechanism is discussed in terms of channel potential fluctuation caused by RDF.