The co-casting process: A new manufacturing process for ceramic multilayer devices

In this work we present a simplified process chain of the conventional multilayer ceramic technology and offer a comfortable method for precise multilayer manufacturing without complex equipment. To circumvent the usual stacking and laminating of single ceramic green tapes to get multilayer devices, a Magnetically Assisted Stencil Printing (MASP) technique was developed. It enables a subsequent casting of ceramic layers and printing of electrode layers. How the co-casting process can be performed either by the use of a modified tape caster at the lab scale or by use of a precision squeegee is described in this paper. Both variants are suited for manufacturing multilayer ceramics with layer thicknesses less than 25 μm. We successfully manufactured pentalayers without cracks or de-laminations from a soft- and also a hard-PZT powder. In a previous work, we investigated sintering additives for PZT. By the use of a PZT-based low-temperature sintering powder composition, cost-effective silver inner electrodes could be realized inside the multilayer ceramics. Piezoelectric low-cost multilayer bending transducers are of particular interest for the use as generators in vibration energy harvesting systems. The proposed triplelayer beam harvests 20 μW (3.2 V) at 71 Hz and an input acceleration of 17.8 m/s2.