Interface electronic structure and Schottky-barrier height in Si/NiSi(010) and Si/PtSi(010) heterostructures: A first-principles theoretical study

Abstract

Nickel monosilicide (NiSi) and Platinum monosilicide (PtSi) are highly promising for applications as contact materials in micro- and nanoelectronic devices. In this article, the interface electronic structure and Schottky barriet height in Si/NiSi(010) and Si/PtSi(010) heterostructures are explored using first-principles density functional theory. Variations in Schottky barrier in Si/NiSi(010) and Si/PtSi(010) systems and workfunctions of NiSi(010), PtSi(010) surfaces due to interface defects are also estimated. In Si/NiSi(010) system, resonance interface states decaying sharply in Si away from the interface are found at ∼8.5 eV below the Fermi energy. On the other hand, localized interface states decaying sharply in Si as well as PtSi away from the interface are found at ∼8.5 eV below the Fermi energy in Si/PtSi(010) system. The Schottky barrier heights in Si/NiSi and Si/PtSi systems are also obtained using MIGS empirical model and bond polarization model and compared with available experimental data and those obtained from first-principles method.