Faculty Member: Prof. Rick Ubic
Room-temperature fabrication (RTF) represents a major technological leap in ceramic processing techniques. This procedure has the potential to save a significant amount of money due to the large amount of time and energy required to operate a furnace at the high temperatures needed for conventional sintering. It may even be possible to tailor this procedure to allow for 3D printing of ferroelectric devices; however, one of the problems with this technique is that it typically produces pellets with greater porosity (~10-20%) than those produced via conventional sintering (~<4%), which inherently results in a decrease in capacitance. Another drawback is that the final pellets contain two phases, the ferroelectric material and the binder, which also results in a decrease in capacitance. Thus, these are two very important challenges that need to be addressed in order to effectively use the RFT method to produce capacitors that are comparable with those produced via conventional high-temperature sintering. The primary goal of this project is to explore different binder materials to increase the density of ceramic pellets while simultaneously decreasing the amount of binder material that is needed to produce them.
Role of Participant(s):
Ferroelectric pellets (i.e., capacitors) will be fabricated using the RTF procedure. In particular, perovskite ceramics in the Pb(ZrxTi1-x)O3 (PZT) series will be synthesized using a solid-state mixed-oxide technique. These PZT ceramics will be characterized for phase-purity via X-ray diffraction and the particle sizes of these powders will be measured via laser particle-size analysis. Dense pellets of these compounds will then be made by coating the particles and mixing them in an aqueous solution with different binding compounds (e.g., Li2MoO4, V2O5, etc.) before pressing them into pellets. The pellets will then be dried in a drying oven and metalized with a thin film of silver. The capacitance of these pellets will be measured at temperatures ranging from 25°C – 150°C using an LCR meter and temperature chamber.