Improvement of Sensitivity of Capacitive Micromachined Ultrasound Transducer

TL;DR

This paper introduces a novel one-generating-multiple-receiving (OGMR) method and circuit design to significantly enhance the sensitivity of a specific CMUT type, achieving nearly threefold noise ratio improvement.

Contribution

It proposes the OGMR method and a specialized circuit model to improve CMUT sensitivity without altering its resonant frequency.

Findings

Signal-noise ratio increased by 2.83 times

Simulation confirms effectiveness of OGMR method

Enhanced sensitivity in specific CMUT type

Abstract

Capacitive Micromachined Ultrasonic Transducer (CMUT) has a wild range of applications in medical detecting and imaging fields. However, operating under self-generating-self-receiving (SGSR) method usually results in poor sensitivity. But the sensitivity cannot be improved simply by increasing the resonant frequency since the frequency of a specific kind of CMUT is designed for specific usage. In this paper, based on one specific type of CMUT, mechanical model is built and simulation analysis is demonstrated. A brand-new method one-generating-multiple-receiving (OGMR) is introduced and a special circuit model has been designed to improve the signal to thermal noise ratio. By increasing the number of receiving capacitors from 1 to 8, we increased the signal-noise ratio to 2.83 times.