@article{MellingerSinghGerhard2005, author = {Mellinger, Axel and Singh, Rajeev and Gerhard, Reimund}, title = {Fast thermal-pulse measurements of space-charge distributions in electret polymers}, issn = {0034-6748}, year = {2005}, abstract = {Space-charge depth profiles in various electret polymers have been measured in both the time and the frequency domain using thermal pulses and waves, respectively. A comparison of the two techniques on corona-charged polytetrafluoroethylene showed that the thermal-pulse method yielded similar results as the thermal-wave technique, but approximately 20-50 times faster. The article discusses sensitivity limitations as well as possible applications, including the real-time monitoring of space-charge decay under UV irradiation. (C) 2005 American Institute of Physics}, language = {en} } @article{MellingerSinghWegeneretal.2005, author = {Mellinger, Axel and Singh, Rajeev and Wegener, Michael and Wirges, Werner and Gerhard, Reimund and Lang, Sidney B.}, title = {Three-dimensional mapping of polarization profiles with thermal pulses}, issn = {0003-6951}, year = {2005}, abstract = {High-resolution, large-area three-dimensional mapping of polarization profiles in electret polymers was carried out by means of a fast thermal pulse technique with a focused laser beam. A lateral resolution of 38 mu m and a near- surface depth resolution of less than 0.5 mu m was achieved. At larger depths, fast thermal diffusion in the metal electrode rather than the laser spot size becomes the limiting factor for the lateral resolution. (c) 2005 American Institute of Physics}, language = {en} }