This work presents a promising ultrasound wearable technology based on a piezoelectric transducer, realized on flexible highly oriented Aluminum Nitride, with significant mechanical displacement in spite of being attached on a rigid support. Circular membranes with different radius sizes, based on 1-μm-thick AlN thin film as the active piezoelectric layer, are designed, fabricated, and characterized. The AlN is deposited on kapton HN substrate with a low sputtering deposition temperature that allows the integration and the compatibility with flexible electronics. Mechanical and thermal stability of kapton makes this polyimide based sheet a potential substrate for flexible piezoelectric thin film technology. The actuation at low voltage (1-10 V) of the AlN membranes is studied in air in the range of ultrasound frequencies, from 0 Hz up to 2 MHz; the voltage amplitude, the shape and displacement of the flexure mode (0, 1) is studied by a Laser Doppler Vibrometer to characterize the mechanical properties of the device. © 2014 Elsevier B.V. All rights reserved.
Piezoelectric ultrasonic transducer based on flexible AlN
Mastronardi V. M.
;Amato M.;De Vittorio M.;
2014-01-01
Abstract
This work presents a promising ultrasound wearable technology based on a piezoelectric transducer, realized on flexible highly oriented Aluminum Nitride, with significant mechanical displacement in spite of being attached on a rigid support. Circular membranes with different radius sizes, based on 1-μm-thick AlN thin film as the active piezoelectric layer, are designed, fabricated, and characterized. The AlN is deposited on kapton HN substrate with a low sputtering deposition temperature that allows the integration and the compatibility with flexible electronics. Mechanical and thermal stability of kapton makes this polyimide based sheet a potential substrate for flexible piezoelectric thin film technology. The actuation at low voltage (1-10 V) of the AlN membranes is studied in air in the range of ultrasound frequencies, from 0 Hz up to 2 MHz; the voltage amplitude, the shape and displacement of the flexure mode (0, 1) is studied by a Laser Doppler Vibrometer to characterize the mechanical properties of the device. © 2014 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
