Design and Performance Analysis of Capacitive Micromachined Ultrasonic Transducer Linear Array

Abstract

An ultrasonic transducer is a key component to achieve ultrasonic imaging. This paper designs a new type of Microelectromechanical Systems (MEMS) based capacitive ultrasonic transducer and a linear array based on the transducer. Through directivity analysis, it can be found that its directivity is weak due to the small size of the designed transducer, but the directivity of the designed linear array is very strong. In order to further suppress the sidelobe interference and improve the resolution of the imaging system and imaging quality, the Dolph-Chebyshev weighting method and the Taylor weighting method are used to process −40dB sidelobe suppression, and satisfactory results are obtained, which can meet actual requirements.

Design Analysis and Human Tests of Foil-Based Wheezing Monitoring System for Asthma Detection

“…It results in a high resonance frequency (in the kHz range) diaphragm with small output signals [19]. Thus, they require signal amplification circuits, which introduce additional noise in the system that must be reduced by added signal conditioning circuits [20,21]. The compromise of using a higher resonance frequency diaphragm is made so that the sensor can respond to the large audible frequency range of an average human (20 Hz-20 kHz).…”

Investigation and analysis of the influence of excitation signal on radiation characteristics of capacitive micromachined ultrasonic transducer

“…Compared with traditional piezoelectric ultrasonic transducers, The CMUT has significant advantages in improving bandwidth, improving imaging resolution, reducing size, reducing costs, achieving mass production and so on (Oralkan et al 2002;Fouan and Bouakaz 2016;Sautto et al 2017;Greenlay and Zemp 2017;Wang et al 2014). And it has a broad application prospects in 3D medical ultrasound imaging (Bhuyan et al 2013), intracardiac ultrasound detection (ICUS) (Nikoozadeh et al 2009), intravascular ultrasound detection (IVUS) (Levent Degertekin et al 2006), tissue harmonic imaging (THI) (Legros et al 2011), high intensity focused ultrasound (HIFU) treatment (Wong et al 2007).…”

Underwater Imaging Using a 1 × 16 CMUT Linear Array

“…The ultrasonic transducer is the core component of ultrasound imaging, and currently piezoelectric micro-machined ultrasonic transducers (PMUTs) based on the piezoelectric effect are widely used [ 4 , 5 ]. However, PMUT performance in underwater and medical applications is limited by material properties and impedance matching issues [ 2 , 6 , 7 ]. Capacitive micro-machined ultrasonic transducers (CMUTs) have many advantages over conventional PMUTs, such as wide bandwidth, high mechanical-electrical conversion efficiency, and ease of integration with electronic circuits to enhance signal-to-noise ratio [ 2 , 8 , 9 , 10 , 11 , 12 ].…”

“…Capacitive micro-machined ultrasonic transducers (CMUTs) have many advantages over conventional PMUTs, such as wide bandwidth, high mechanical-electrical conversion efficiency, and ease of integration with electronic circuits to enhance signal-to-noise ratio [ 2 , 8 , 9 , 10 , 11 , 12 ]. Furthermore, CMUT membranes have low mechanical impedance, which makes them match well with air and other fluid media, and are suitable for manufacturing in large arrays [ 2 , 6 ]. These characteristics promote CMUTs as the development direction for next generation ultrasonic transducers.…”