Metallurgical properties and electrical characteristics of palladium silicide-silicon contacts

Abstract The fabrication, metallurgical properties, and electrical characteristics of palladium silicide (Pd 2 Si) contacts to n -type Si have been investigated. Pd 2 Si/Si contacts are similar in electrical and metallurgical behavior to PtSi/Si contacts, but can be fabricated at much lower temperatures. Pd was found to react readily with Si at 200°C to form a silicide phase which was identified as Pd 2 Si from X-ray diffraction analysis. The electrical resistivity of the silicide is 40 × 10 −6 Ω cm as determined from sheet resistivity measurements. The barrier height at the Pd 2 Si/Si interface was determined from differential capacitance measurements to be 0.745±0.015 V. Current-voltage measurements and activation energy analysis gave barrier heights within this same range. Contact resistance measurements were made on contacts to Si surfaces with phosphorus doping levels of 2×10 20 /cm 3 . Resistance values obtained are comparable to both theoretical predictions and measurements reported on PtSi and Al contacts to Si.