resumo
We report on the fabrication of multiscale three-dimensional (3D) micropatterning of Ba-0.5(Zr0.2Ti0.8)O-3 - (0.5)(Ba0.7Ca0.3)TiO3 (BZT- BCT) electroceramic material using soft lithographic PDMS moulds. The ceramic microcomponents were successfully consolidated by Epoxy Gel Casting from stable aqueous suspension of BZT-BCT material. A successful aqueous processing of electroceramic material was employed with surface protection of powder particles against hydrolysis as considerably an important parameter to achieve high solid loading suspension with pseudoplastic behaviour suitable for casting in micro scale moulds. The process to obtain micro sized pattern of material was divided in two steps: (i) production of high quality SU-8 master moulds and the respective negative replicas in PDMS (soft mould) by photolithography and soft mould replication, respectively; (ii) casting the soft moulds by stable high solid loading BZT-BCT suspensions in presence of gelation agents followed by de -moulding, drying and sintering. The resulting green micropattern structures show interesting features, including complex structures with a periodic variations through their length and, multiscale array of hexagonal shaped pillars of different aspect ratios (AR) (max AR approximate to 8 with approx 320 mu m of height and side length 40 mu m) with smooth side wall features along height. The green pillar arrays were further sintered to show the suitability of aqueous processing of material and proposed casting method. (C) 2017 Elsevier Ltd. All rights reserved.
palavras-chave
CERAMIC MICROCOMPONENTS; LITHOGRAPHY
categoria
Materials Science
autores
Kaushal, A; Olhero, SM; Singh, B; Bhardwaj, C; Sharma, I; Bdikin, I; Button, T; Ferreira, JMF
nossos autores
Ajay Kaushal
Bolseiro de pós-Doutoramento
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)
Susana Maria Henriques Olhero
Professor Auxiliaragradecimentos
Authors, Ajay Kaushal and Budhendra Singh thanks to the Foundation for Science and Technology of Portugal (FCT) for the financial support the grant references SFRH/BPD/77598/2011 and SFRH/BPD/76184/2011, respectively. The support of CICECO, University of Aveiro is also acknowledged.