Low frequency Piezoelectric Micromachined Ultrasonic Transducers optimized for concrete structures.

Development of piezoelectric micromachined ultrasonic transducers

Piezoelectric micromachined ultrasonic transducers (pMUTs) are an example of the application of MEMS technology to ultrasound generation and detection, which is expected to offer many advantages over conventional transducers. In this work, we investigate pMUTs through novel design and fabrication methods. A finite element (FE) model, with original tools to measure device performance, was develo...

High Frequency and High Fill Factor Piezoelectric Micromachined Ultrasonic Transducers Based on Cavity Soi Wafers

This paper presents a high frequency and high fill factor piezoelectric micromachined ultrasonic transducer (PMUT) array, which is fabricated with a simple and CMOS compatible process based on commercially available cavity SOI wafers. This 2-mask process eliminates the need for through-wafer etching and enables 10× higher fill factor and thereby higher acoustic performance. PMUTs based on both ...

Silicon micromachined ultrasonic immersion transducers

Broadband transmission of ultrasound in water using capacitive, micromachined transducers is reported. Transmission experiments using the same pair of devices at 4, 6, and 8 MHz with a signal-to-noise ratio greater than 48 dB are presented. Transmission is observed from 1 to 20 MHz. Better receiving electronics are necessary to demonstrate operation beyond this range. Furthermore, the same pair...

Micromachined piezoelectric ultrasonic transducer with ultra-wide frequency bandwidth

Defect Imaging by Micromachined Ultrasonic Air Transducers

dynamic ranges in excess of 100 dB are attainable in pulseecho operation using commercially available discrete mmponents. Transmission experiments through aluminum and composite plates verify more than 100 dB dynamic range and demonstrate the ability of cMUTs to image defects in air at 2.5 MHz. W e also present a variation on cMUT design which improves the useful bandwidth of the device, permit...