Tuning of large piezoelectric response in nanosheet-buffered lead zirconate titanate films on glass substrates

TL;DR

This paper introduces a novel method to grow well-oriented PZT thin films on glass substrates using nanosheet seed layers and optimized deposition conditions, significantly enhancing piezoelectric response compared to previous approaches.

Contribution

The study presents a new approach combining nanosheet seed layers and controlled deposition frequency to achieve high piezoelectric response in PZT films on glass.

Findings

Achieved a piezoelectric response of 280 pm/V, nearly tripling previous records.

Demonstrated that reduced clamping correlates with increased piezoelectric response.

Validated the method's effectiveness through microscopy and analytical calculations.

Abstract

Renewed interest has been witnessed in utilizing the piezoelectric response of $PbZr_{0.52}Ti_{0.48}O_{3}$ (PZT) films on glass substrates for applications such as data storage and adaptive optics. Accordingly, new methodologies are being explored to grow well-oriented PZT thin films to harvest a large piezoelectric response. However, thin film piezoelectric response is significantly reduced compared to intrinsic response due to substrate induced clamping, even when films are well-oriented. Here, a novel method is presented to grow preferentially (100)-oriented PZT films on glass substrates by utilizing crystalline nanosheets as seed layers. Furthermore, increasing the repetition frequency up to 20 Hz during pulsed laser deposition helps to tune the film microstructure to hierarchically ordered columns that leads to reduced clamping and enhanced piezoelectric response evidenced by transmission electron microscopy and analytical calculations. A large piezoelectric response of 280 pm/V is observed in optimally tuned structure which almost triples the highest reported piezoelectric response on glass. To confirm that the clamping compromises the piezoelectric response, denser films are deposited using a lower repetition frequency and a $BiFeO_{3}$ buffer layer resulting in significantly reduced piezoelectric responses. This paper demonstrates a novel method for PZT integration on glass substrates without compromising the large piezoelectric response.