Size-dependent Schottky barrier height in self-assembled gold nanoparticles

Au nanocluster/6H-SiC Schottky contacts were electrically characterized by conductive atomicforce microscopy, collecting a high number of current-voltage I-V curves. The main observedresult is the Schottky barrier height SBH dependence on the cluster size. The SBH increases from1.35±0.01 to 1.77±0.01 eV when the cluster size increases from 1.5 to 6.8 nm and it tends,asymptotically, to the theoretical SBH of the macroscopic contact Au/SiC 1.9 eV. This behavioris interpreted considering the thermoionic transport theory through the Au cluster/SiC barriercoupled with the concept of ballistic transport within few electron quantum dots.