Structural and electrical characteristics of R.F. magnetron sputtered ZnO films

We investigated the effects of both bottom electrodes and processing parameters on the physical and electrical properties of ZnO films deposited by R.F. magnetron sputtering. We found that the preferential c-axis growth of deposited ZnO films depends on the type of bottom electrode: Both Al and Au bottom electrodes enhance the growth of c-axis orientation in ZnO films, while no clear evidence for any preferential growth was observed in case of Cu and Si. The resistivity of ZnO films deposited on Au and Al bottom electrodes was greater than 10⁶ Ω cm. The ranges of dielectric constant of Al/ZnO and Au/ZnO samples were 8-14 and 13-16, respectively. Dissipation factors change from 0.02 to 0.05. In general, as c-axis orientation enhances, dielectric constant and dissipation factor increase and decrease, respectively.