Electrical characterization of aluminum thin films on etched PCB substrate

Abstract

Thermal evaporation in a vacuum is employed in the deposition of aluminum thin film on an etched PCB substrate using the Kinney Vacuum Coating System. The thin film’s resistance as a function of length was studied. The resistance was found to vary linearly with length. The sheet resistivity was measured using the 4-point probe. The resistivity value was 0.458 Ω-cm². The thin film underwent SEM and AFM scanning. The scans showed that the coating had a porous surface morphology with thickness ranging from 0.3-1.9 μm. The thin film has a potential application as a variable resistor, strain gauge and gas sensor.