Origin of High Mobility in InSnZnO MOSFETs

Abstract

The origins of higher mobility characteristics of In-Sn-Zn-O (InSnZnO) MOSFETs than those of conventional In-Ga-Zn-O (InGaZnO) MOSFETs were investigated. Comprehensive analyses of temperature and surface carrier concentration ( ${N} _{s}$ ) dependence of mobility revealed the aspects of potential profile around mobility edge ( ${E} _{c}$ ) in InSnZnO MOSFET. Incorporated Sn atoms were found to increase the potential fluctuation around ${E} _{c}$ at low ${N} _{s}$ compared to conventional InGaZnO MOSFET, but enhance the overlapping of electron orbitals of cations with In atoms, which results in mobility improvement by band transport.

Keywords

• Oxide semiconductor
• mobility
• InSnZnO
• InGaZnO
• BEOL