Fabrication of Lead Zirconate Titanate Piezoelectric Thin Films through Sol-Gel Deposition

Overview

Stevens Institute of Technology Considering the popularity of lead zirconate t itanate (PZT) for its desirable piezoelectric properties, this study was focused on the fabrication of PZT thin films with improved qualities and reduced cracks. PZT thin film recipes were developed and tested by optimizing the thickness and heating/cooling processes of the film and without utilizing a seed-layer. Thin films were deposited through the sol-gel method and spin-coated onto a substrate. The films then underwent pyrolysis and annealing to remove organics and crystallize. Light microscopy and image processing were used to analyze the quality of the thin films by measuring the average area of the largest crack-free regions in each thin film. It was found that multi-layered PZT thin films contained less cracks but exhibited rougher surfaces. It was also found that raising pyrolysis temperatures gradually to annealing temperature was optimal to decrease thermal stress and the amount of cracks. Upon observing the films directly after pyrolysis, it was concluded that the annealing stage was a major source of the film cracks and should be improved to decrease the amount of cracks. A completely crack-free PZT thin film was not fabricated, but future work should focus on improving the annealing stage, improving multi-layered thin films, and testing piezoelectric properties of fabricated thin films.