ultrasonic transducer;
polymer transducer;
PVDF;
high frequency imaging;
MEMS;
minimally invasive procedures;
D O I:
10.1016/S0924-4247(02)00323-0
中图分类号:
TM [电工技术];
TN [电子技术、通信技术];
学科分类号:
0808 ;
0809 ;
摘要:
Spherically focused, high frequency (30-50 MHz) ultrasonic imaging transducers are fabricated using poly(vinylidene) difluoride (PVDF) film and a membrane deflection technique that is compatible with CMOS microelectronics fabrication. Micromachined ultrasonic transducers with 0.75-2.00 mm-diameter apertures and f-numbers of 1.30-2.45 are fabricated and characterized. The transducers exhibit focused radiation patterns with 50 mum axial resolution and 51-92 mum lateral resolution and bandwidths of 80-110% around center frequency values. A miniature preamplifier hybrid circuit, which is designed to be mounted within the transducer housing, is fabricated and characterized to reveal a low noise level of 5.3 nV/rootH(z). Tissue imaging capabilities of the micromachined ultrasonic transducers are demonstrated through successful imaging of human cadaveric aorta. (C) 2003 Elsevier Science B.V. All rights reserved.