Development of a Polymer Based Capacitance Ultrasonic Transducer Array

• Main Authors: Yi-Ze Chen, 陳奕澤
• Other Authors: Da-Chen Pang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/36130296133886542237

碩士 === 國立高雄應用科技大學 === 機械與精密工程研究所 === 101 === In this research a bistatic type polymer-based capacitive micromachined ultrasonic transducer (CMUT) is developed. The numbers of projectors and receivers of the bistatic CMUT can be selected based on our needs. The bistatic CMUT has a variety of choices in operation and is demonstrated for surface roughness measurements. The membranes of the bistatic CMUT are separated into two groups with a full transmission/ full reception, majority transmission/ majority reception, majority transmission/ minority reception, minority transmission/ majority reception, minority transmission/ minority rece membrane ratio of two to one. The bistatic CMUT can be operated at five different modes: ption. It can strengthen projectors or receivers based on target scattering condition. The adhesion process of polymer-based CMUT is carefully analyzed to improve its quality. This study focuses on three critical factors: release layer, adhesive stress and adhesive temperature. It does not only correct failure of adhered surfaces between membrane and side wall but also decrease thermal stress in the membrane. The final yield of bistatic CMUT is 25% which is twice better than the past. The basic characteristics of the bistatic CMUT are tested. The sandpapers with surface roughness Rq varying from 25μm to 162μm can be identified at any mode. The minority transmission/ majority reception mode is found to obtain better energy efficiency. The current bistatic CMUT has disadvantages of short operation life and low production yield and requires further study before applying for large sensor array. Keywords：Capacitive Micromachined Ultrasonic Transducer (CMUT), Bistatic, Roughness