Results of experiments on application of various interlayers between LTCC (Low Temperature Cofired Ceramics) substrate and thick-film PZT (Lead Zirconate - Titanate) are described in this work. Thick-film intermediate layers were based on several dielectric materials: TiN, Al₂O₃, SiC, TiO₂, SiC, YSZ, BN. Seven screen printable pastes were prepared on the base of powders of mentioned materials with addition of glass and organic vehicle. The substrates were made of 951 (DuPont), CeramTapeGC (CeramTec) and HL2000 (Heraeus) LTCC tapes. Sandwich type transducers, consisting of barrier layer, gold bottom electrode, PZT layer and silver top electrode were prepared and characterized. Basic piezoelectric parameters – permittivity, effective charge constant (d_33(eff)) and remanent polarization were determined. The best properties were obtained for substrates made of 951. In general, interlayers based on TiO₂, SiC and Al₂O₃ improved permittivity and charge constant comparing to bare substrates. For example, for 951 substrate the PZT layer exhibited d_33(eff) equal to 160, 215, 250 and 230 pC/N for bare substrate, TiO₂ interlayer, SiC interlayer and Al₂O₃ interlayer, respectively. In case of CeramTape GC substrates determined permittivity was equal to 215, 245, 235 and 275 for bare substrate, TiO₂ interlayer, SiC interlayer and Al₂O₃ interlayer, respectively. In case of TiN and BN materials the parameters were considerably deteriorated.

Date Published: 10 November 2016
PDF: 7 pages
Proc. SPIE 10161, 14th International Conference on Optical and Electronic Sensors, 101610C (10 November 2016); doi: 10.1117/12.2244195

Published in SPIE Proceedings Vol. 10161:
14th International Conference on Optical and Electronic Sensors
Piotr Jasiński, Editor(s)