Ultrasonic Detection of Defects in Multilayered Ceramic Capacitors for Active Implantable Medical Devices

Published

August 8, 2011

Author(s)

Sudook A. Kim, Ward L. Johnson, Grady S. White, Roger Roberts

Abstract

Resonant ultrasound spectroscopy (RUS) was used to measure the acoustic frequencies of surface-mountable X7R multilayered ceramic capacitors (MLCC), with the aim of determining whether RUS can serve as a nondestructive method for detecting structural flaws that affect the reliability of capacitors incorporated in active implantable medical devices. Measurements were made on capacitors in the as-manufactured condition and after exposure to a variety of treatments, including elevated vibration/temperature/current, thermal shock, microindentation, and focused-ion-beam (FIB) milling of a linear flaw. Changes in RUS spectra induced by the indentations and FIB flaw were found to be comparable in magnitude to the margins of error of the measurements. However, accelerated stress and thermal shocks resulted in much more noticeable changes. These results provide preliminary evidence that RUS measurements provide a feasible basis for detecting structural flaws that are precursors to electrical failures of MLCC.

Proceedings Title

Materials and Processes for Medical Devices 2011

Conference Dates

August 8-10, 2011

Conference Location

Minneapolis, MN

Pub Type

Conferences

Keywords

active implantable medical devices, acoustic resonance, AIMD, capacitors, cracks, multilayer ceramic capacitors, NDE, nondestructive evaluation, resonant ultrasound spectroscopy, ultrasonics

Citation

Kim, S. , Johnson, W. , White, G. and Roberts, R. (2011), Ultrasonic Detection of Defects in Multilayered Ceramic Capacitors for Active Implantable Medical Devices, Materials and Processes for Medical Devices 2011, Minneapolis, MN (Accessed December 10, 2024)