Nanotechnology-Enabled Ultrasound Transducers

Ultrasound transducer is a core component for transductions between acoustic energy and electrical energy in numerous applications including medical imaging, therapy, human health monitoring and non-destructive testing (NDT). The rapid advancement of nanotechnology in recent years has opened up new prospects for ultrasound transducers. The integration of nanomaterials and nanofabrication techniques with ultrasound transducers offers ample opportunities for enhancing transducer performances and opening up new applications. The objective of this review is to provide the state-of-the-art advancement of nanotechnology-enabled ultrasound transducers, with a focus on nanomaterials applied in both piezoelectric transducers and optoacoustic transducers, as well as fabrication techniques of nanostructured materials for ultrasound transducers. Firstly, nanomaterials and nanofabrication techniques for both piezoelectric transducers and optoacoustic transducers are reviewed and summarized. Representative nanotechnology-enabled ultrasound transducers for biomedical and NDT applications are then examined. Finally, a discussion of major challenges and future research directions of nanotechnology-enabled ultrasound transducers are presented.