Characteristics of the SiN Uniaxial Strained NMOSFET with Channel Fluorine Implantation

Abstract

Channel fluorine implantation (CFI) has been successfully integrated with silicon nitride contact etch stop layer (SiN CESL) to further improve the channel hot electron stress (CHES) and constant voltage stress (CVS) reliability of n-channel metal-oxide-semiconductor field-effect-transistor with HfO2/SiON gate stack. Although the improvement of transconductance, drain current and subthreshold swing due to the fluorine passivation is screened out by the effect of uniaxial tensile strain, the result clearly demonstrates that integrating the CFI process in the SiN CESL-strained device can further suppress the CHES- and CVS-induced threshold voltage shift.