HCI Temperature sense effect from 180nm to 28nm nodes

A lot of efforts were made to take into account self-heating to improve aging models for hot carrier induced degradation. As a general approach, MOS transistor parameter drift measured at various stress voltages was renormalized to a common junction temperature using an apparent activation energy. We found that such an approach can induce significant errors since the temperature sense effect can represent up to 50% of the apparent measured Ea value. The error was attributed to temperature sense effect on measured drift, which was consistent with Vth and mobility models.