1Department of Microelectronics, Xi'an Jiaotong University, Xi'an 7100492Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA3Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA
Fermi Level Unpinning and Schottky Barrier Modification by Ti, Sc and V Incorporation at NiSi2/Si Interface
1Department of Microelectronics, Xi'an Jiaotong University, Xi'an 7100492Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA3Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA
摘要A new method is proposed to modify the Schottky barrier height (SBH) for nickel silicide/Si contact. Chemical and electrical properties for NiSi2/Si interface with titanium, scandium and vanadium incorporation are investigated by first-principles calculations. The metal/semiconductor interface states within the gap region are greatly decreased, which is related to the diminutions of junction leakage when Ti-cap is experimentally used in nickel silicide/Si contact process. It leads to an unpinning metal/semiconductor interface. The SBH obeys the Schottky-Mott theory. Compared to Ti substitution, the SBH for electrons is reduced for scandium and increases for vanadium.
Abstract：A new method is proposed to modify the Schottky barrier height (SBH) for nickel silicide/Si contact. Chemical and electrical properties for NiSi2/Si interface with titanium, scandium and vanadium incorporation are investigated by first-principles calculations. The metal/semiconductor interface states within the gap region are greatly decreased, which is related to the diminutions of junction leakage when Ti-cap is experimentally used in nickel silicide/Si contact process. It leads to an unpinning metal/semiconductor interface. The SBH obeys the Schottky-Mott theory. Compared to Ti substitution, the SBH for electrons is reduced for scandium and increases for vanadium.
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