Micro-electro-mechanical systems capacitive ultrasonic transducer with a higher electromechanical coupling coefficient

Micro & nano letters

article

Jing Miao¹  Wenjiang Shen²  Changde He³  Chenyang Xue¹  Jijun Xiong¹ 

[1] National Key Laboratory for Electronic Measurement Technology, North University of China;Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences;Key Laboratory of Instrumentation Science and Dynamic Measurement, Ministry of Education

关键词: silicon;    elemental semiconductors;    silicon-on-insulator;    wafer bonding;    electromechanical effects;    ultrasonic transducers;    capacitive transducers;    micromechanical devices;    micromachining;    vibrations;    membranes;    finite element analysis;    reliability;    capacitance;    electromechanical coupling coefficient;    capacitive micromachined ultrasonic transducer;    impedance matching;    propagation medium;    microelectromechanical system capacitive ultrasonic transducer;    silicon on insulator;    wafer bonding;    optimum geometric dimensions;    membrane mechanical vibration;    electrical characteristics;    finite-element analysis;    operation mode;    device safety;    device reliability;    equivalent stress;    operation-collapse voltage;    bottom electrodes;    glass substrate surface;    parallel parasitic capacitance;    Si;    SiO2;   

DOI  :  10.1049/mnl.2015.0186

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

One of the key components in anesthesia delivery system is face mask. The anatomical face mask is also called as face piece and is designed to fit the contour of patient face and deliver the anesthetic gases. Wide ranges of masks are available in the market. Different varieties of masks have been evolved after understanding the difficulties of typical anatomical face mask.[1] Truly speaking these masks are typical anatomical masks with some modification to overcome the problem. [2] Transparent mask is one of the innovative ideas which are developed with the main intention of identification of patient condition viz, bleeding from the mouth, vomitus or oral secretions and cyanosis. The transparent mask though it has many advantages it is not free from disadvantages. Iatrogenic injury to patient due to use of damaged masks and or infections are common. Hence maximum care should be taken to prevent these. [2] In this report we share our experience. A transparent silicon mask was fallen on the ground accidentally while shifting the patient from operation table to transportation trolley. Surprisingly it was not noticed by any one, as the attending anesthesiologist and attendants were busy in shifting the patient. While doing the anesthesia machine check for next case we could notice the face mask was missing. After 15minutes of search and close look in operation theatre we could identify the mask as it was fallen on the ground. The silicon transparent mask and the floor color were almost similar (Figure 1) and hence it was very difficult to identify with distance. The face mask consists of three parts namely, body, mount and the edge. We recommend the masks with either colored rim or colored mount (Figure 2 & 3) so that mask can be easily identified.

【 授权许可】

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