Doped ZrO2 for future lead free piezoelectric devices

The ferroelectric and piezoelectric properties of doped ZrO2 prepared by chemical solution deposition (CSD) are investigated. Doping with different elements such as Mg, In, La, and Y leads to a stabilization of the constricted hysteresis. As shown in a previous work, for the constricted hysteresis of ZrO2, the piezoelectric response is significantly larger compared to ZrO2 with a normal hysteresis. The Mg doped ZrO2 shows a strong temperature and cycle stability. For the piezoelectric properties, a magnesium concentration of 7% shows the largest piezoelectric response with a piezoelectric coefficient of >10 pm/V, as well as the best cycle stability. Due to thicker films, which can be realized by the CSD technique, the shown doped ZrO2 films are a promising candidate for energy related applications such as piezoelectric energy harvesting as well as for microelectromechanical systems.