Dependence of Channel Width and Length on MOSFET Matching for 0.18 um CMOS Technology

Abstract

Mismatch characterization has been performed on 0.18 μm CMOS technology for a wide range of dimensions for both N and P MOSFETs. It is the first time that a great number of dimensions has been tested : this allows to show the evolution of mismatch parameter AVt with both length and width. Matching degradation for short devices is related to the increase of effective channel doping level associated to the larger pocket influence. The effect of lateral isolation on the distribution of polysilicon grain size and orientation could explain mismatch decrease for narrow channel devices.