Lanthanide and Ir-based dual metal-gate/HfAlON CMOS with large work-function difference

Abstract

Metallic diffusion through high-K HfO(2), caused by high temperature metal-nitride decomposition, was reduced by using robust HfAlON. Useful dual effective work-function (phi(m,eff)) of 4.25 and 5.15 eV are obtained in TaTb(0.2)N/HfAlON and Ir/HfAlON at 1.7nm EOT. Good dual phi(m,eff) of 4.15 and 4.9 eV are also obtained in Yb(x)Si/HfAlON and Ir(x)Si/HfAlON FUSI-gates by reduced metal diffusion at lower temperature.