On the Generation and Recovery of Interface Traps in MOSFETs Subjected to NBTI, FN, and HCI Stress

摘要

A common framework for interface-trap (N{sub}(IT)) generation involving broken ≡ Si-H and ≡ Si-O bonds is developed for negative bias temperature instability (NBTI), Fowler-Nordheim (FN), and hot-carrier injection (HCI) stress. Holes (from inversion layer for pMOSFET NBTI, from channel due to impact ionization, and from gate poly due to anode-hole injection or valence-band hole tunneling for nMOSFET HCI) break ≡ Si-H bonds, whose time evolution is governed by either one-dimensional (NBTI or FN) or two-dimensional (HCI) reaction-diffusion models. Hot holes break ≡ Si-O bonds during both FN and HCI stress. Power-law time exponent of N{sub}(IT) during stress and recovery of N{sub}(IT) after stress are governed by relative contribution of broken ≡ Si-H and = Si-O bonds (determined by cold- and hot-hole densities) and have important implications for lifetime prediction under NBTI, FN, and HCI stress conditions.