Towards Understanding Interaction Between Hot Carrier Ageing and PBTI

Early works on device ageing often focus on one source, while devices in a circuit suffer degradation from different sources. There are only limited information on the impact of ageing from one source on ageing from a different source. This work researches into the interaction of ageing induced by Hot Carriers with that by Positive Bias Temperature Instability (PBTI). It will be shown that one can slow down the other and the ageing can be substantially overestimated without considering their interaction. Although a PBTI after Hot Carrier Ageing (HCA) will increase the degradation, a HCA following a PBTI can result in a reduction in ageing for long channel devices. The defect responsible for their interaction will be explored.