Experimental evidence of giant fluctuations in the electrical response of very thin SnO/sub 2/ films

Abstract

A simple comb structure provided with p/sup +/ silicon temperature sensor and Al electrodes predeposited on Si/SiO/sub 2/ substrates has been used to study the room temperature time-dependent voltage response of undoped and Sb doped SnO/sub 2/ sol-gel derived thin films as a function of injected constant current. Giant voltage fluctuations were revealed for input currents higher than a certain threshold that varied as a function of film technology and surface topography. The results were qualitatively interpreted in terms biased percolation model.