Integration Of Ultrasonic Sensor Array Design And Testing

Ultrasound Imaging has extensive applications in medicine, non-destructive testing,mapping of submarine topography, wreck salvage underwater. But conventional ultrasoundimaging system has large volume, high cost and it is not convenient to use, which limited itsscope of application. Improving levels of integration of the imaging system, cutting costs，increasing performance, reducing the volume and Increasing speed of ultrasound imaging isthe future of ultrasound imaging research. The design and integrated manufacturing ofpiezoresistive ultrasonic transducer is studied based on ultrasound imaging’s application.At first，structure of MEMS piezoresistive transducer is designed. To use Finite elementanalysis to analysis the sensitivity and resonance frequency of structure, and to realizeoptimization of the structure, different size structure has been analysised.150K,75K,68Kand34K micro sensing beam structure is designed, and the cantilever structure withcorresponding frequency is designed too, theoretical simulation shows that, compared withthe structure of cantilever beam its sensitivity improved by an average of8.9db. The sensorsignal amplification circuit is designed, it can amplify and filter the signal.According to the ultrasound imaging theory which based on piezoresistive transducerarray and relevant processing technology, the parameters of the transducer, such as distance,Number and angular resolution, has been designed. Analysis relation between the angle ofresolution and reference direction.We preliminaryly try to integrate many transducers in one wafer, which will provide thebasis for design of Small volume, low cost and high resolution Imaging system. Package ofbare chip is designed for connecting to the circuit and protecting bare chip. Package of thetransducer and circuit is designed. We have simulate and analysis effect of acoustic windowand acoustic characteristics of the package used in the water.In the end, we have tested the resistance, sensitivity and resonance frequency consistencyof the transducer, The results show that the array parameters is consistent. And test thedirectivity of the transducer unit and array. Data is Acquisition by transducer array. Direction of Multiple target can be known synchronously through digital beam forming technology. Weuse transducer array for imaging and have some progress.