An Analytical Model for Deposited Charge of Single Event Transient (SET) in FinFET

Abstract

With feature size scaling down, the effect of single event transient (SET) on the reliability of circuits is necessary to be considered. The bipolar amplification effect plays a key role in the charge collection of SET of nano-meter FinFET devices. It is important taking into account the bipolar amplification to calculate deposited charge, which is always obtained by a linear model dependency on linear energy transfer (LET) and silicon film thickness. Based on radiation-induced generation rate model and genetic arithmetic, an accurate analytical for the deposited charge of SET in FinFET is proposed. The effects of LET, volume of particle hit, characteristic radius and decay time of Gaussian function on the deposited charge are analyzed by the proposed model. The dependence of the device structure on the deposited charge is also discussed by the model. The results indicate that the presented model agrees with TCAD well. Compared with TCAD, the proposed model has an average relative error 0.002% while the linear model has an average relative error 50.5% for LET ranging from 3 to 110 MeV·cm²/mg. Due to large sensitive volume of the particle hit in source and drain areas, the deposited charge has two maxima in source and drain areas and a minimum round the gate-drain junction of fin. The deposited charge increases with the characteristic radius and decay time decrease and the relative error between TCAD and the proposed model represent a reduction trend.