Optimization in the Design and Fabrication of a PZT Piezoelectric Micromachined Ultrasound Transducer (PMUT)

摘要

This paper presents an optimized way of lead zirconate titanate (PZT) deposition in orderto selectively grow three different (100/001), (110), and (111) crystal orientation in two differentthickness ranges, thinner and thicker than 400 nm. The thickness of the PZT layer is also optimizedto not diminish the generated bending moment more than 10%. A 1μm PZT layer with (100/001)dominant crystal orientation and highly columnar crystal structure is deposited and used in thefabrication of a circular PMUT. The PMUT has a 410 μm diameter and resonates at 462 kHz withthe displacement of 1200 nm/V.