Specific Contact Resistivity Reduction Through Ar Plasma-Treated TiO2-x Interfacial Layer to Metal/Ge Contact

Abstract

We demonstrate contact resistivity reduction by inserting an Ar plasma-treated TiO2-x heavily doped interfacial layer to metal/semiconductor contact to overcome a Fermi-level pinning problem on germanium (Ge). A specific contact resistivity of 3.16x10(-3) Omega.cm(2) on moderately doped n-type Ge substrate (6 x 10(16)cm(-3)) was achieved, exhibiting x584 reduction from Ti/Ge structure, and x11 reduction from Ti/undoped TiO2/Ge structure. A novel doping technique for TiO2 interfacial layer at low temperature using Ar plasma was presented to lower S/D contact resistance in Ge n-MOSFET.