Electrical properties of ZrO2 thin films

Abstract Electrical properties of sputtered ZrO2 thin films have been studied using impedance spectroscopy, isothermal transient ionic current and current–voltage measurements. ZrO2 have different dielectric properties when fresh, i.e. newly deposited, or aged. A fresh sample can arbitrarily show two different behaviors consisting of a d.c. conductivity with a relaxation peak superimposed on it. The d.c. conductivity shows either of two different values. The aged sample has a lower d.c. conductivity and the relaxation peak is found at much lower frequencies. Fresh samples of ZrO2 also show switching behavior which aged samples never do. Analyses of current–voltage characteristics indicate hopping as the main conduction process.