Influence of Annealing Temperature on Electronic and Dielectric Properties of ZrO2 Thin Films on Si

Zirconium oxide (ZrO2) films were deposited on (100) silicon substrates by DC reactive magnetron sputtering of zirconium target at an oxygen partial pressure of 6x 10(-2) Pa. The as-deposited films were annealed in air for 1 hour at different temperatures in the range 773 - 1173 K. The influence of annealing temperature on the structural properties of ZrO2 films and the electrical properties like Capacitance-Voltage and Current-Voltage of the capacitors of the type Al/ZrO2/p-Si were studied. The capacitance and dielectric constant of the capacitors were found to increase with increase in annealing temperature from 773 to 973 K, however, with further increase in annealing temperature to 1173 K they were found to decrease. In addition, the leakage current density was decreased from 1x 10(-6) to 4x 10(-7) A/cm(2) at 1V gate bias voltage and the electrical conduction mechanism was dominated by Schottky emission for all the films in lower electric fields.