Investigation and Analysis of Mismatching Properties for Nanoscale Strained MOSFETs

Abstract

This paper investigates and analyzes the matching properties of nanoscale strained MOSFETs under various bias conditions. Through a comprehensive comparison between coprocessed strained and unstrained PMOSFETs, the impact of process-induced uniaxial strain on the matching performance of MOS devices has been assessed and analyzed. Our examination indicates that, in the low-gate-voltage-overdrive (vertical bar V(gst)vertical bar) regime, the normalized drain current mismatch (sigma(Delta I(d))/I(d)) of the strained device is almost the same as that of the unstrained one at a given transconductance to drain current ratio (g(m)/I(d)). In the high vertical bar V(gst)vertical bar linear regime, the sigma(Delta I(d))/I(d) for the strained device is smaller than that of the unstrained one because of its smaller normalized current factor mismatch. In the high vertical bar V(gst)vertical bar saturation regime, the improvement in the sigma(Delta I(d))/I(d) for the strained device is further enhanced because of the reduced critical electric field at which the carrier velocity becomes saturated.