Processing strategy and composite regulation on dielectric performance in Li2O–Al2O3–B2O3 dielectric systems using SrTiO3

Siyu Xiong, Deqin Chen, Xiaowei Zhu, Guobin Zhu, Hongxiang Xiao*, Weiping Gong, Laijun Liu, Jibran Khaliq, Chunchun Li*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

In this paper, we investigated the effect of processing parameters and composite regulation on the structure and property relationship of lightweight low-permittivity Li2O–Al2O3–B2O3 dielectric system. Li2BAlO4 ceramic and (1 − x)Li2BAlO4–xSrTiO3 ceramics were synthesized using a conventional solid-state reaction method. Thermodynamic analysis, sintering temperature, phase formation, crystal structure, and microwave dielectric properties were investigated. Thermal analysis revealed a melting temperature of 847°C, suggesting a comparatively low temperature for the sintering of Li2BAlO4 ceramics. Li2BAlO4 crystalized into a monoclinic structure with P21/c space group, with [Al2B2O8] rings connected by [BO3] triangles and [AlO4] tetrahedra through Al–O–Al bridges. Dense Li2BAlO4 ceramics with a relative density of ∼97.7% were sintered at 750°C and had optimal microwave dielectric properties with relative permittivity (εr) of 5.13, quality factor (Q × f) of 22 610 GHz, and the temperature coefficient of resonance frequency (τf) of −112.5 ppm/°C. The 0.88Li2BAlO4–0.12SrTiO3 composite ceramic has excellent microwave dielectric properties with εr = 8.83, Q × f = 14 000 GHz, τf = 4.6 ppm/°C. The ceramics also demonstrated an inert behavior with silver electrodes proving its application in low-temperature cofired ceramic (LTCC) technology.

Original languageEnglish
Pages (from-to)1-11
Number of pages11
JournalJournal of the American Ceramic Society
Early online date5 May 2024
DOIs
Publication statusE-pub ahead of print - 5 May 2024

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