Low threshold voltage and high drive current poly-silicon thin film transistors using Ytterbium metal gate and LaAlO3 dielectric

Abstract

We have demonstrated high-performance metal-gate/high-k Ytterbiuni/LaAlO3 low-temperature poly-Si (LTPS) thin film transistors (TFTs) that have both high drive current capability and high voltage operation. The high drive current is due to the combined effect of low work-function Ytterbium metal gate and high gate capacitance by high-k LaAlO3 dielectric. The high breakdown voltage is also due to the high-k LaAlO3 dielectric to give larger physical thickness at the same equivalent oxide thickness (EOT). The good reliability and full process compatibility are the other important merits for Ytterbium/LaAlO3 device.