Impact of Fermi level pinning inside conduction band on electron mobility of In<inf>x</inf>Ga<inf>1−x</inf>As MOSFETs and mobility enhancement by pinning modulation

Abstract

We clarified that Fermi levels at InGaAs MOS interfaces are pinned inside conduction band (CB) and that this pinning severely degrades the effective mobility. Also, the energy position of the Fermi level pinning (FLP) is found to be tunable. It is experimentally shown that the increase in the difference between the FLP position and the CB minimum (CBM) leads to high mobility at high N <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> region. Also, possible physical origin for this FLP is proposed.