Understanding charge traps for optimizing Si-passivated Ge nMOSFETs

Abstract

For the first time, two different types of electron traps are clearly identified in Ge nFETs with Type-A controlled by the HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layer thickness and Type-B by the Si growth induced Ge segregation. Only Type-B are responsible for mobility degradation and they do not saturate with stress time, while the opposite applies to Type A. A PBTI model is proposed and validated for the long term prediction.