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Abstract
Fast rising electrical fields cause switching of a ferroelectric material and induce electron emission from its surface. Moreover, this process is strongly related to the degree of polarization change in the material. Simultaneous observation of the switching current and the electron beam pulse demonstrate that electrons are emitted due to successive partial switching and even due to switching from the remanent to the saturation polarization state. Generally it has to be distinguished between the setting free of electrons by the fast polarization inversion and the extraction of the beam. Calculations show that the field at the sample surface is strongly bent due to the grid structure of the electrode. Consequently, low energy electrons are turned off and captured by the electrode. This can be avoided by introducing an additional extraction potential. Thus significant current amplitudes were achieved also from thin ceramic emitters down to 85 μm thickness. The experimental technique is described.