摘要
This letter discusses the hot carrier stress (HCS) degradation mechanisms for different gate voltages ( V ) in FinFET devices, and finds the abnormal relationship between HCS degradation and body current under high V . According to the distributions of lifetime (τ)- I and τ -drain current (I ), it is found that the τ under the high V is related to the I instead of the I . In addition, as the V increases from low to middle to high values, the HCS degradation mechanism exhibits single vibrational excitation, electron-electron scattering, and multiple vibrational excitation (MVE) models, respectively. Therefore, the HCS degradation mechanism at higher V is not dominated by the traditional impact ionization but by the carrier concentration of the channel. Finally, according to the results of fitting MVE model, the reason for breaking the Si-H bonds to form dangling bonds is the bending vibrational mode.