Mechanism Of Dc Conduction In Silicon Nanoparticles Network

The current-transport mechanism of silicon nanoparticles dispersed in linseed oil have been investigated using I-V measurement on their metal-nanocomposite-metal structures. The conductivity of the nanocomposite was observed to depend largely on the ratio of nc-Si to linseed oil binder used to form the composite. The critical concentration for DC conductance was found to be about 70-80 wt.% nc-Si in the oil. The conductivity however does not scale with further increase in the particle concentration, which as such cannot be explained completely in terms of percolation theory only. An analysis of the effect of the concentration of nc-Si in the binder matrix, as well as the applied electric field strength from the I-V measurement, revealed that the current-transport consisted of a combination of transport mechanism usually associated with charge transport in dielectric materials. Main electrical characteristics, such as transitional voltage (V-trans), critical voltages (V-tr) and barrier height (phi(FN)), were derived from the analysis of different plots of I-V data using the Fowler-Nordheim (FN), Richardson-Schottky (RS)/Poole-Frenkel (PF) emission as well as the Space Charge Limited Current (SCLC) models.