Caution: Abnormal Variability Due to Terrestrial Cosmic Rays in Scaled-Down FinFETs

The variability due to the displacement damage defect is investigated for various bulk FinFET technology nodes. A random displacement damage from point to clustered defects is introduced by natural terrestrial radiation in arbitrary locations in the silicon channel region. Energy level, position, and size of the defect clusters are considered as variables, and the impact on device performance is investigated for various technology nodes with the aid of the TCAD simulation. It is found that even a displacement defect can cause significant device degradation as the technology node scales down beyond the 10-nm node. Particularly, the abnormal variability may become an issue at sub-6-nm node due to a limited volume of the fin width and the comparable size of the cluster defect.