Structure and microwave dielectric behaviour of low-temperature-fired Li2Zn1−xCoxTi3O8 (x = 0–0.07) ceramics for low temperature co-fired ceramic applications
- 10 Downloads
Low-temperature-fired Li2Zn1−xCoxTi3O8 (x = 0, 0.03, 0.04, 0.05, 0.06, 0.07) ceramics with 1.5 wt% Li2O–B2O3–SiO2–CaO–Al2O3 (LBSCA) glass as sintering aid were attained through a traditional solid-state-reaction method, and the relationship between their structures and microwave dielectric properties were thoroughly investigated. X-ray diffraction patterns revealed that the solid solutions composed of Li2ZnTi3O8 and Li2CoTi3O8 were produced. The main peaks were identified with the cubic spinel phase of the Li2(Zn,Co)Ti3O8. Co substitution successfully lowered the sintering temperature of Li2ZnTi3O8 to approximately 900 °C and accelerated its densification when LBSCA glass was used as the sintering aid. The cobalt content considerably influenced grain homogeneity, grain size and dielectric polarizability, as well as the variation in relative permittivity (εr) and quality factor (Q × f). When x = 0.04, Li2Zn0.96Co0.04Ti3O8 ceramic sintered at 900 °C had the most uniform grain size and exhibited optimum microwave dielectric properties, having a relative permittivity of 21.61, Q × f of 79,100 GHz and temperature coefficient of resonance frequency (τf) of − 12.3 ppm/°C. Thus, it showed potential for low temperature co-fired ceramic applications.
This work was supported by the National Natural Science Foundation of China under Grant Nos. U1809215, 51772047 and 61871069. Science and technology support program of Sichuan Province under Grant Nos. 2018GZ0320, 2016JQ0016 and 19ZDYF0529. And “111” Project under Grant No. T2018001.
- 6.T. Sebastian, Dielectric Materials for Wireless Communications (Elseivier Publishers, Oxford, 2008)Google Scholar
- 28.H.W. Chen, H. Su, H.W. Zhang, Low temperature sintering and microwave dielectric properties of the LBSCA-doped (Zn0.95Co0.05)2SiO4 ceramics. J. Mater. Sci.: Mater. Electron. 26, 2820–2823 (2015)Google Scholar
- 31.T. Lei, J. Chen, Z. Xu, H. Su, Y. Li, X. Tang, Microwave dielectric properties of the low-temperature-fired Li2ZnTi3O8–Li2TiO3 ceramics for LTCC applications. J. Mater. Sci.: Mater. Electron. 29, 14705–14709 (2018)Google Scholar