Effect of variable body bias technique on pMOSFET NBTI recovery

A study on the negative bias temperature instability (NBTI) recovery of a pMOSFET under variable body bias (VBB) is presented. The forward body bias enhanced NBTI recovery mechanism is proposed with evidence on the VBB dependency. Further, the influence of surface potential and the gate oxide electric field on the recovery indicated that the relaxation of the positive charge and interface trap played a different role in the NBTI recovery stage. It is shown that the forward VBB technique can achieve improvement in terms of drive capability and NBTI lifetime.