Strained-Si nMOSFET with a raised source/drain structure

Abstract

In this paper, electrical characteristics for strained-Si n-channel metal-oxide-semiconductor field-effect-transistors (nMOSFETs) combining raised source/drain (RSD) structure and cobalt silicide have been studied using the devices with various gate pattern areas (W × L). A strained-Si device with RSD structure provides an additional driving current enhancement (up to 12%) for large-area devices (W × L = 10 × 10 μm 2 ) compared to a strained-Si device without RSD. Further improvement of 24% for device areas down to W × L = 0.15 × 0.15 μm 2 indicates that obvious pattern effects exist in strained-Si without RSD case, which is mainly due to the formation of silicide agglomeration at the source/drain (S/D) region and is responsible for the increased S/D resistance.