A study of NBTI by the statistical analysis of the properties of individual defects in pMOSFETS

Capture and emission of positive charge in individual defects has been studied using small area pMOSFETs. Analysis techniques similar to the ones used in RTS studies of nMOSFETs have been employed, with the difference that the capture process has been stimulated by stress pulses. We found that the recoverable part of the NBTI effect can be fully explained by capture and emission of these defects. As a consequence, a couple of previously used approaches trying to explain NBTI have to be discarded. The individual capture and emission time constants are widely spread over many orders of magnitude and are thermally activated with activation energies between 0.5 and 1.0 eV.