Suppression of VT variability degradation induced by NBTI with RDF control

VT 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 VT 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.