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An experimental study is presented to probe the interface barriers of dopant-segregated silicide–Si diodes with internal photoemission. The spatial information of the interface dipoles, which is believed to be the cause of the effective Schottky barrier height (SBH) modification, is extracted from the field dependence of the barrier heights. A clear difference between the dopant segregation (DS) junctions and a pure Schottky junction is found: Boron DS modifies the effective SBH by forming a \p^+\- \n junction while arsenic DS forms a “Shannon” junction with a fully depleted 1.5-nm doping depth in front of the silicide. [ABSTRACT FROM AUTHOR]

Complete gate silicidation has recently been demonstrated as an excellent technique for the integration of metal gates into MOSFETs. From the various silicide gate materials NiSi has been shown to be the most scalable. In this paper, a versatile method for controlling the workfunction of an NiSi gate is presented. This method relies on doping the poly-Si with various impurities prior to silicidation. The effect of various impurities including B, P, As, Sb, In, and Al is described. The segregation of the impurities from the poly-Si to the silicide interface during the silicidation step is found to cause the NiSi workfunction shift. The effect of the segregated impurities on gate capacitance, mobility, local workfunction stability, and adhesion is studied. [ABSTRACT FROM AUTHOR]