1.5×10−9 Ωcm2 Contact resistivity on highly doped Si:P using Ge pre-amorphization and Ti silicidation

Abstract

Record-low contact resistivity (pc) for n-Si, down to 1.5×10−9 Q-cm2, is achieved on Si:P epitaxial layer. We confirm that Ti silicidation reduces the pc for n-Si, while an additional Ge pre-amorphization implantation (PAI) before Ti silicidation further extends the pc reduction. In situ doped Si:P with P concentration of 2×1021 cm−3 is used as the substrate, and dynamic surface anneal (DSA) boosts P activation. In addition, TiOx based metal-insulator-semiconductor (MIS) contact is also studied on Si:P but is found to suffer from low thermal stability.