Crystal structure, Raman spectra and microwave dielectric properties of novel low-temperature cofired ceramic Li4GeO4

摘要

A low-permittivity and low-loss ceramic, Li4GeO4, was fabricated via solid state reaction route. XRD showed that a single orthorhombic Li4GeO4 phase with olivine structure was prepared over the sintering temperature range of 660-740 degrees C. Dense ceramic sintered at 720 degrees C revealed excellent microwave properties, with epsilon(r) similar to 6.99, Q x f similar to 47,813 GHz (at 15.5 GHz), and tau(f) similar to - 159.2 ppm/degrees C. The microwave dielectric performances were analyzed with the intrinsic characteristics of crystal structure by ionic polarizability and Raman spectra. Additionally, the Li4GeO4 ceramic showed good chemical compatibility with Ag sintered at 720 degrees C. In the low-temperature cofired ceramic (LTCC) application, aforesaid results manifested that Li4GeO4 ceramic was considered as a potential candidate. (C) 2021 Elsevier B.V. All rights reserved.