Sputtered Piezoelectric Films as Materials for Flexible Devices and Sensors: A Review

The demand for innovative and versatile technologies in wearable electronics has catalyzed research into functional materials that can seamlessly integrate with complex and curved surfaces. Recent advances in sputtering technology have not only enabled precise control over the thin-film composition and crystal structure on various substrates, including flexible ones, but also made it easier to optimize a sensor's performance for specific applications. Piezoelectric thin films produced by sputtering techniques are recognized for their exceptional electromechanical properties and offer a promising approach for developing low-cost, high-performance flexible sensors. These sensors have a wide range of applications, from wearable devices to environmental monitoring. In this article, we present and discuss the use of sputtered piezoelectric thin films as materials for flexible devices and sensors. The growth of these thin films through sputtering, their piezoelectric properties, and the sensor fabrication processes are detailed, with a focus on challenges that remain to be addressed. We also discuss the difficulties in optimizing film performance while ensuring mechanical durability, emphasizing the importance of material engineering. Additionally, the broad spectrum of applications for flexible devices and sensors is highlighted.