Elastic relaxation in intrinsically-strained Fins: Simulations, physical and electrical characterization

Abstract

Elastic relaxation after Fin formation in intrinsically-strained materials was presented. Reported simulations are correlated with NBD strain measurements and are consistent with length dependence of drain current in sSOI FinFETs. Stress in the Fin's channel region depends on Fin length and height. dingle layer structured Fins are much more resistant to elastic relaxation than dual layer structured Fins, due to overall structure height. On dual layer structure Fins, significant relaxation is expected for LFin shorter than 750nm, while single layer structured Fins do not relax significantly until 300nm. For transistor layout, elastic relaxation effects should be modeled or circumvented. Fin Length effects need to be added to other layout effects in Spice models.