Pd/Au/SiC Nanostructured Diodes for Nanoelectronics: Room Temperature Electrical Properties

Pd/Au/SiC nanostructured Schottky diodes were fabricated embedding Au nanoparticles (NPs) at the metal-semiconductor interface of macroscopic Pd/SiC contacts. The Au NPs mean size was varied controlling the temperature and time of opportune annealing processes. The electrical characteristics of the nanostructured diodes were studied as a function of the NPs mean size. In particular, using the standard theory of thermoionic emission, we obtained the effective Schottky barrier height (SBH) and the effective ideality factor observing their dependence on the annealing time and temperature being the signature of their dependence on the mean NP size. Furthermore, plotting the effective SBH as a function of the effective ideality factor we observe a linear correlation, indicating that the Au NPs act as lateral inhomogeneities in the Schottky diodes according to the Tung's model. Therefore, we can control the size, fraction of covered area, and surface density of such intentionally introduced inhomogeneities. The application of the Tung's model for the electronic transport in inhomogeneous Schottky contacts allow us to obtain, in particular, the homogeneous SBH. These nanostructured diodes are proposed as possible components of integrated complex nanoelectronic devices.