Influence of fin number on hot-carrier injection stress induced degradation in bulk FinFETs

In this paper, hot-carrier injection (HCI) stress has been used to investigate the reliability of n-channel FinFET devices with different fin numbers. Threshold voltage (VTH) shift, subthreshold swing and transconductance variation were extracted to evaluate the degradation of the device under stress. FinFET devices with fewer fins show more serious performance degradation due to hot-carrier injection stress. It is suggested that the existing of coupling effect between neighboring fins reduces the inversion charge density and equivalent electric field in multi-fin devices, which causes better reliability than single-fin devices.