TY - JOUR
T1 - Fluid compressional properties sensing at microscale using a longitudinal bulk acoustic wave transducer operated in a pulse-echo scheme
AU - Yanez, Jesus
AU - Uranga, Arantxa
AU - Barniol, Nuria
N1 - Publisher Copyright:
© 2021 The Authors
PY - 2022/2/1
Y1 - 2022/2/1
N2 - Acoustic devices have been widely used as smart chemical and biochemical sensors since they are sensitive to mechanical, chemical, optical or electrical perturbations on their surfaces; making them a reliable option for noninvasive detection of changes in physical properties of liquid samples for real-time applications. Here we present a longitudinal acoustic wave device for study of compressional properties of liquids in microfluidic systems, with the particularity of pulse-echo mode of operation. We have studied at a microscale the interaction between longitudinal acoustic waves and the compressional properties of liquid samples, interrogating the fluids with short pulses of ultrasound at GHz, finding a direct relationship between the magnitude of the bulk modulus or the specific acoustic impedance of liquids and the amplitude of the output voltage produced by acoustic echoes received by the aluminum nitride transducer. Analytical expressions and FEM simulations support the detection mechanism, while applications such as classification of liquids and detection of concentration change in solutions experimentally demonstrate the method. This contribution overcomes current restrictions of film acoustic resonators such as fragility of operation in liquid environments, high manufacturing cost or limitations regarding narrow microchannels; offering an alternative to applications that demand ultra-low consumption, miniaturization, versatility (it offers multi-frequency operation in 1 – 10 GHz range) and ease of readout (peak voltage).
AB - Acoustic devices have been widely used as smart chemical and biochemical sensors since they are sensitive to mechanical, chemical, optical or electrical perturbations on their surfaces; making them a reliable option for noninvasive detection of changes in physical properties of liquid samples for real-time applications. Here we present a longitudinal acoustic wave device for study of compressional properties of liquids in microfluidic systems, with the particularity of pulse-echo mode of operation. We have studied at a microscale the interaction between longitudinal acoustic waves and the compressional properties of liquid samples, interrogating the fluids with short pulses of ultrasound at GHz, finding a direct relationship between the magnitude of the bulk modulus or the specific acoustic impedance of liquids and the amplitude of the output voltage produced by acoustic echoes received by the aluminum nitride transducer. Analytical expressions and FEM simulations support the detection mechanism, while applications such as classification of liquids and detection of concentration change in solutions experimentally demonstrate the method. This contribution overcomes current restrictions of film acoustic resonators such as fragility of operation in liquid environments, high manufacturing cost or limitations regarding narrow microchannels; offering an alternative to applications that demand ultra-low consumption, miniaturization, versatility (it offers multi-frequency operation in 1 – 10 GHz range) and ease of readout (peak voltage).
KW - AlN
KW - Bulk acoustic wave
KW - HBAR
KW - Microfluidics
KW - Piezoelectric
KW - Pulse-echo
KW - Time-of-flight
KW - Ultrasonic microsensors
UR - http://www.scopus.com/inward/record.url?scp=85121615757&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/9ae423cd-9dc6-3a51-8993-4fe63d953805/
U2 - 10.1016/j.sna.2021.113334
DO - 10.1016/j.sna.2021.113334
M3 - Article
AN - SCOPUS:85121615757
SN - 0924-4247
VL - 334
JO - Sensors and Actuators A: Physical
JF - Sensors and Actuators A: Physical
M1 - 113334
ER -