Comparison between piezoelectric method and ultrasonic signal analysis for crack detection in type II multilayer ceramic capacitors
| Autor: | Yves Danto, Yves Ousten, Bernard Tregon, Laurent Bechou, Said Mejdi |
|---|---|
| Přispěvatelé: | Import, Ims |
| Rok vydání: | 1998 |
| Předmět: |
Signal processing
Materials science [SPI.NANO] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics Acoustics Short-time Fourier transform Management Science and Operations Research Piezoelectricity law.invention Capacitor symbols.namesake Transducer Fourier transform law Electronic engineering symbols Ultrasonic sensor Safety Risk Reliability and Quality Ceramic capacitor |
| Zdroj: | Quality and Reliability Engineering International. 14:91-94 |
| ISSN: | 1099-1638 0748-8017 |
| Popis: | SUMMAKY In this paper we present a comparison between two non-destructive techniques for crack detection in MLCCs. First, if a type II MLCC is biased with a DC field, the capacitor becomes temporarily 'poled' and can act as a transducer. This is induced by a residual piezoelectric effect used in the impedance spectroscopy method. Second, we used a scanning ultrasonic system working in the 10-100 MHz frequency bandwidth. To understand the ultrasonic signature, we used time-of-flight (TOF) detection with short-time Fourier transform (STFT) analysis to determine the depth and nature of defects with high accuracy. An application of digital signal processing to the characterization of defects is presented for a lot of MLCCs with cracks defects. For comparison, the same lot was tested with the piezoelectric method. The two techniques are closely correlated. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text