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Piezoelectric Sensors : Towards Next-generation of Selfpowering Smart Sensor Systems
ELECTRICAL AND COMPUTER SYSTEMS ENGINEERING
Dr Tridib Saha Lecturer PhD
Research expertise : Piezoelectric Materials , Acoustic Wave Devices , Sensors , Instrumentation , Nanotechnology
E : tridib . saha @ monash . edu T : + 603 5514 4948
Piezoelectric sensors utilize the ability to directly convert any mechanical stress to electricity , and are extensively used in a wide range of physical , chemical and biological sensors . Based on the same property , piezoelectric materials have shown great promise as mechanical energy harvesters to power the next generation of low-power electronics . This type of energy scavenging offers a great potential for prolonging the finite power capacity of batteries in wireless sensor networks , implantable biosensors , remote and mobile environmental sensors , and recently popularized wearable smart devices . Our research addresses the challenges in design and low-power instrumentation of piezoelectric sensor systems that simultaneously function as sensors and energy harvesters . Our current focus is towards wearable sensors for detection of human exposure to UV radiation , and alternate power sources for such wearable devices .
Displacement profile of piezoelectric UV sensor
Resonant ZnO Nanostructure Integrated Flexible SAW Sensors for Healthcare Wearable Sensing Applications
Dr Ajay Achath Mohanan Lecturer , PhD
Research expertise : Surface Acoustic Wave ( SAW ) sensors , ZnO nanostructures , RF magnetron sputtering , Hydrothermal growth
E : ajay . mohanan @ monash . edu T : + 603 5514 6252
Flexible surface acoustic wave ( SAW ) devices integrated with resonant zinc oxide ( ZnO ) nanostructures as sensing media can realize highly sensitive healthcare wearable sensors in future with potential applications for real-time monitoring of vital signs such as pulse rate , blood pressure and breathing patterns , as well as sensing toxic gases and UV radiation . Further , the structural flexibility and tiny device footprint of flexible SAW sensors along with their ability to be interrogated wirelessly and passively using an onboard antenna make these sensors convenient to be attached to the human body for sensing purposes with minimal obstruction to daily activities .
Our research deals with design and fabrication of highperformance flexible ZnO / polymer layered flexible SAW devices , followed by on-chip integration of resonant ZnO nanorods as sensing medium on these devices . ZnO nanorods of precisely tuned dimensions could be grown on the surface of the SAW device through continuous flow hydrothermal method operated under surface reaction-limited zone .
Photoconduction in ZnO nanowirebased UV sensor
FESEM image of 4-micron thick reactive-RF magnetron sputtered c-axis oriented ZnO thin film grown on Si ( 100 ) substrate for SAW propagation .
FESEM image of ZnO nanowalls grown using hydrothermal method on SAW device electrodes for humidity sensing applications .
R E S E A R C H E R P R O F I L E 2022 / 2023