Interfacial Resistive Properties of Nickel Silicide Thin Films to Doped Silicon

Improved means of electrical access to nanotechnology devices and accurate nanoscale characterization of electrical properties of ultrathin layers constituting such electrical contacts is of utmost interest to nanoelectronics researchers. This paper reports on the characterization of interfacial resistive properties of ohmic contacts to doped silicon, incorporating thin films of nickel silicide. Silicon doping was achieved by carefully designed ion implantation of antimony (for n-type) and boron (for p-type). Cross Kelvin resistor test structures were used to extract the specific contact resistivity SCR values for the different ohmic contacts fabricated. SCR values, which are quantitative characteristics of interfacial resistive properties, as low as 5.0 x10-9 Omega cm2 for contacts to antimony-doped silicon and 3.5 x10-9 Omega cm2 to boron-doped silicon were estimated. These experimental results, representing the lowest such values measured, were based on a rigorous evaluation technique and verified by finite element modeling.