Some strategies to (co)-sinter refractory functional oxides at low temperature by spark plasma sintering
March 10-15, 2019
The sintering at high temperatures (1000-1400°C) of refractory oxides widely used in electronic devices, raises several issues related to defects, chemistry, microstructure and interface control. Reducing sintering temperatures below 900°C is a major challenge in particular when high relative densities, optimal microstructure and the control of reactivity at interfaces (grain boundaries, multi-materials) are mandatory. In this context, we propose to highlight some strategies focused on interfaces and phases control through two different illustrations of our recent works. The first one is focused on Micro-Electromechanical System (MEMS) energy harvesters (EH) using piezoelectric materials. We will show the potentiality of SPS to co-sinter in one step and below 900°C complex devices such as screen-printed PbZrTiO3 in sandwich between two gold electrodes and supported on a stainless steel substrate. Here, the sintering aids in the pastes should be removed if possible or adapted for good adhesion, and delamination and bending of the multilayer EH must be avoided. We also intent to get rid of the annealing process after the SPS sintering. The second illustration reports on the ambitious goal to sinter zirconia ceramics at temperatures below 400°C. Recently, the exploration of non-equilibrium sintering, through transient liquid phase, hydrated precursors, or by using solvent assisted sintering, Flash sintering and Spark Plasma Sintering has been investigated to sinter ZnO and thermodynamically unstable materials at very low temperature [2-5]. Here, our approach is based on the use of specific precursors and deals with the control of transient non-equilibrium phases to find the driving force to establish the most favorable pathway for enhanced densification.
. M. I. Rua-Taborda, O. Santawitee, A. Phongphut, B. Chayasombat, C. Thanachayanont, S. Prichanont, C. Elissalde, J. Bernard, H. Debéda, "Printed PZT Thick Films Implemented for Functionalized Gas Sensors", Key Engineering Materials, 777,158, 2018
.B. Dargatz, J. Gonzalez Julian, M. Bram, P. Jakes, A. Besmehn, L. Schade, R. Röder, C. Ronning and O. Guillon, “FAST/SPS sintering of nanocrystalline zinc oxide—Part I: Enhanced densification and formation of hydrogen-related defects in presence of adsorbed water, J. Eur. Ceram Soc. 36, 1207, 2016
. S. Funahashi, J. Guo, H. Guo, K. Wang, A. L. Baker, K. Shiratsuyu, and C. A. Randall, "Demonstration of the cold sintering process study for the densification and grain growth of ZnO ceramics," Journal of the American Ceramic Society, 100, 546, 2017.
. Luo J., “The scientific questions and technological opportunities of Flash sintering: from a case study of ZnO to others ceramics”, Scripta Mater., 146, 260, 2018
. T. Herisson de Beauvoir, A Sangregorio, I. Cornu, C. Elissalde and M. Josse, “Cool-SPS: an opportunity for low temperature sintering of thermodynamically fragile materials” J. Mater. Chem. C, 6, 2229, 2018
Catherine Elissalde, U-Chan Chung, Mario Maglione, Graziella. Goglio, Michaël Josse, Hélène Debéda Debéda, and Maria-Isabel Rua-Taborda, "Some strategies to (co)-sinter refractory functional oxides at low temperature by spark plasma sintering" in "Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities", Rishi Raj, University of Colorado, USA Olivier Guillon, Forschungzentrum Jülich, Germany Hidehiro Yoshida, National Institute for Materials Science, Japan Eds, ECI Symposium Series, (2019). https://dc.engconfintl.org/efe_advancedmaterials_ii/55