Effects of fluorine based double plasma treatment on electrical and reliability characteristics of Ge pMOSFETs

Abstract

In order to reduce bombardment or chemical etching damage of Ge pMOSFET treated by F-based plasma, an additional O2 or/and N2 plasma treatment was applied on the high-k gate dielectric in this work. The sample treated by F-based plasma followed with O2 and N2 plasma exhibits a lower off-state current, gate leakage current, sub-threshold swing and interface trap density simultaneously; meanwhile, the on-state current and carrier mobility are similar. Also, the better uniformity and reliability characteristics can be achieved. A F-based double plasma treatment is a promising technique to effectively passivate oxide traps and enhance performance of Ge MOSFETs without EOT degradation.