Piezoelectric micromachined ultrasound array transducer with 31 channels for photoacoustic imaging

Photoacoustic imaging (PAI) is a non-invasive medical imaging technique that has been studied by many research groups. It surpasses the penetration-depth limits of optical imaging and is able to provide functional imaging for tumor-vascular interactions and hemoglobin oxygenation mapping. The imaging quality is dominated by the transducer performance; thus, the transducer plays an important role. In this study, we examined a piezoelectric micromachined ultrasound transducer (pMUT) array with 10 MHz resonant frequency for PAI systems. pMUTs can be used with array or endoscopic probes due to their small size by bulk micromachining process. Additionally, their receiving sensitivity and power efficiency are higher than those of general thickness-mode piezoelectric transducers.