Temperature dependent current transport in Schottky diodes of nano structured ZnO grown on Si by magnetron sputtering

Nano-structured ZnO thin-film is grown by dc-magnetron sputtering on Si substrates using a sintered ZnO target. As grown film is characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). About 165 nm thick ZnO film is revealed with highly oriented, nano-structured columnar grains. Nickel (Ni) Schottky diodes are fabricated and characterized by current-voltage (I-V), capacitance-voltage (C-V) and temperature dependent current-voltage (I-V-T) measurements. Charge transport mechanism is studied from the I-V measurements performed in the temperature range from 300-400K. Both reverse and forward currents increased with temperature. Increase in barrier height along with a decrease in ideality factor with increasing temperature indicates thermionic field emission is the dominant charge transport mechanism in our devices.