Space charge behaviour and ion migration in a printed wiring board

We used the pulsed electroacoustic (PEA) space charge measurement system to observe copper ion migration occurring in an insulation layer of a metal-base PWB, and compared the space charge profile with ion impurities detected by ion chromatography and copper distribution observed by EPMA. We show that the space charge measurement is effective for investigating not only high-voltage insulation, but also electronic insulation.