Research On The Defects Characterization And Software Of Micro-wave Ceramic Capacitor Based On Noise

Microwave technology is playing an increasing role in information system, such as satellite broadcasting, communication technology, military radar, etc. Micro-wave ceramic capacitor has become an indispensable basic component in electronic industry. The current situation presents higher demands on its reliability. Various defects, however, are the very root influencing factors of the reliability. At present, manufacturers rely mainly on accelerated life test to research the reliability of devices. But this method is time-consuming, destructive, and it couldn’t be employed to detect each sample. The low frequency noise is closely related to the inner material defects and damage of devices. It could be used as a parameter to characterize defects. And then this method could become a valid evaluative tool for the reliability.This paper begins with usual failure modes and inner failure mechanisms. The inner defects which lead devices to failure have been summarized. Then an in-depth research has been made to find the relationships between defects, leakage and noise. Because of the special of the samples, two plans have separately been made to measure the I-V characteristics and the noise. Depending on the noise measurement plan, a hardware circuit has been constructed and the virtual instrumentation has been employed to control the function of noise signal acquisition and analysis, and the noise measurement system is made up of those two components. After that, the designed system is employed to research the voltage property and temperature characteristic. According to the results of the Ⅰ-Ⅴ characteristic, leakage transport mechanisms in different voltage parts could be concluded. The noise experiments have been made on different batches of capacitors and voltages. Then, another two noise experiments have been made on the samples which have separately been disposed in high pressure and high temperature. In accordance with the noise measurement results, analyses have been made of the noise variation, in which the leakage transport mechanisms discussed before could be employed to explain the generation and variation of the noise.