High resolution PEA charge distribution measurement system

The pulsed electroacoustic (PEA) method is widely known to be an excellent method for the measurement of the space charge distribution which accumulates in thick dielectric materials (1-5 mm). However, because of its lower resolution in the depth direction, conventional application of this method is less suitable for thin specimens than the laser-induced pressure wave method. A new PEA measurement system which can now be applied to thin dielectric materials (<100 μm). The resolution in the depth direction is improved to less than several μm by detecting signals in a wide frequency range. In addition, the system employs a deconvolution technique with FFT in order to compensate for the frequency characteristics of the piezoelectric sensor. The new PEA measurement system is expected to be useful for quantitative and non-destructive measurement of the space charge distribution in dielectric films