Comparison Of The Work Function Of Pt-Ru Binary Metal Alloys Extracted From Mos Capacitor And Schottky-Barrier-Diode Measurements

This paper describes a systematic comparison of work function for the Pt-Ru binary-alloy metals, extracted from capacitance-voltage (C-V) characteristics of MOS capacitors and the current-voltage (C-V) and (C-V) characteristics of Schottky-barrier diodes. Our results indicate that the work function of the Pt-Ru binary-alloy system can be tuned over the wide range of 4.8-5.2 eV. Furthermore, the results indicate that the change of film properties, i.e., resistivity, work function, and crystal structure, with composition is consistent with the equilibrium-phase diagram and that the work function in the face-centered cubic and the hexagonal-close-pack single-phase regions is only weakly dependent on composition while a strong dependence is observed in the intermediate compositional range. It is also observed that work-function values obtained from the Schottky I-V analysis are significantly lower than those extracted from the MOS C-V data. © 2007 IEEE