Self-heating effect in FinFETs and its impact on devices reliability characterization

摘要

The impact of self-heating effect (SHE) on device reliability characterization, such as BTI, HCI, and TDDB, is extensively examined in this work. Self-heating effect and its impact on device level reliability mechanisms is carefully studied, and an empirical model for layout dependent SHE is established. Since the recovery effect during NBTI characterization is found sensitive to self-heating, either changing VT shift as index or adopting μs-delay measurement system is proposed to get rid of SHE influence. In common HCI stress condition, the high drain stress bias usually leads to high power or self-heating, which may dramatically under-estimate the lifetime extracted. The stress condition Vg = 0.6∼0.8Vd is suggested to meet the reasonable operation power and self-heating induced temperature rising. Similarly, drain-bias dependent TDDB characteristics are also under-estimated due to the existence of SHE and need careful calibration to project the lifetime at common usage bias.