The bias-temperature effect in a rectifying Nb/C₆₀/p-Si structure: evidence for mobile negative charges in the solid C₆₀film

Abstract

Solid C60 film was grown on a p-type Si substrate and a rectifying Nb/C60/p-Si structure was prepared. Capacitance-voltage (C-V) measurements showed that for temperatures above 260 K the C-V curve of the Nb/Co60/p-Si structure shifted along the voltage axis depending on biasing conditions. We analysed this effect to reveal the existence of mobile negative charges in the C60 layer and determine the density of the mobile charges.