To highlight the peculiarities of sintering under electric field, 8 mol% yttria‐stabilized zirconia (8YSZ) specimens were tested in a sinter‐forging apparatus equipped with laser scanners and power supply. This enables to monitor axial and radial shrinkage under controlled ac field with current limitation. Current flow results in expansion related to an increase of several hundreds of °C. This proves that the whole specimen experiences, due to Joule heating, significantly higher temperatures than its environment.

Matsuoka-type zinc oxide (ZnO) varistor material was synthesized using a conventional solid-state reaction method. X-band electron paramagnetic resonance (EPR) data revealed that Mn ions substitute in the ZnO lattice with a 2+ paramagnetic state. Co ions with either 3+ or 2+ oxidation states are only detectable at cryogenic temperatures. A Cr(3+) EPR signal was strongly suppressed or masked by a Mn(2+) signal. Photoluminescence and electrical results indicated that the varistor sample has fewer intrinsic defects and much higher resistivity as compared to undoped and metal-ion doped ZnO.

Effect of local electrical properties on the electrostatic discharge withstand capability of multilayered chip ZnO varistors J. Appl. Phys.

Patterned ceramic films with constant thickness can be processed by a soft lithographic method. By using micromolding in capillaries, the slurry is forced to flow through channels created in an elastomer stamp. After drying, layers deposited on an amorphous carbon substrate were sintered under inert atmosphere. Free‐standing ceramic structures with high aspect ratio were obtained with lateral resolution better than 1 µm. Dimensional changes were monitored in comparison to films deposited on stiff sapphire substrate. This technique enables to process a large variety of structures, from optical or electronic components to sieve and MEMS applications.

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