Experimental study on carrier transport mechanism in ultrathin-body SOI nand p-MOSFETs with SOI thickness less than 5 nm

Abstract

The electrical characteristics of ultrathin-body SOI CMOSFETs with SOI thickness ranging from 2.3 nm to 8 nm are intensively investigated. As a result, it is demonstrated, for the first time, that electron mobility increases as SOI thickness decreases, when SO, thickness is in the range from 3.5 nm to 4.5 nm. In addition, it is demonstrated that, when SOI thickness is thinner than 4 nm, slight (even atomic-level) SOI thickness fluctuations have a significant impact on threshold voltage, gate-channel capacitance, and carrier mobility of ultrathin-body CMOSFETs.