Electrical Properties of Self-Assembled Nano-Schottky Diodes

A bottom-up methodology to fabricate a nanostructured material by Au nanoclusters on 6H-SiC surface is illustrated.Furthermore, a methodology to control its structural properties by thermal-induced self-organization of the Au nanoclustersis demonstrated. To this aim, the self-organization kinetic mechanisms of Au nanoclusters on SiC surface were experimentallystudied by scanning electron microscopy, atomic force microscopy, Rutherford backscattering spectrometry and theoreticallymodelled by a ripening process. The fabricated nanostructured materials were used to probe, by local conductive atomic forcemicroscopy analyses, the electrical properties of nano-Schottky contact Au nanocluster/SiC. Strong efforts were dedicated tocorrelate the structural and electrical characteristics: the main observation was the Schottky barrier height dependence of thenano-Schottky contact on the cluster size. Such behavior was interpreted considering the physics of few electron quantum dotsmerged with the concepts of ballistic transport and thermoionic emission finding a satisfying agreement between the theoreticalprediction and the experimental data. The fabricated Au nanocluster/SiC nanocontact is suggested as a prototype of nano-Schottkydiode integrable in complex nanoelectronic circuits.