International Congress on Ultrasonics 2023
Beijin, China (Beijing Friendship Hotel - The City Nature)
Listen2Future at the 2023 International Congress on Ultrasonics
"Ultrasonic venting: Venting materials for packaging of air-coupled ultrasonic MEMS transducers" was presented at the 2023 International Congress on Ultrasonics in Beijin (China) by Tomás Gómez Alvarez-Arenas, from our partner CSIC.
Summary
Introducing the concept of ultrasonic venting: Use of MEMS ultrasonic air-coupled transducers, both PMUT and CMUT, is promising in industrial applications like non destructive testing (NDT), quality control, proccess control and materials characterization. Air-coupled provide the capability to perform fast and in-line inspections, completely contactless, while high frequency (>100 kHz) is critical to provide the demanded spatial and temporal resolution. However, for the packaging of the MEMS it is critical to identify suitable materials for venting, providing protection of the membrane against dust and humidity, but providing high transparency at ultrasonic frequencies. Materials already in use as acoustic vents (in MEMS microphones and speakers) are not suitable for this application, as the use of ultrasonic frequencies introduces new requirements and demands. This paper reviews these requirements, analyzes the suitability of materials used today as acoustic vents, and proposes lines of search to identify suitable materials for this application.