Novel Low‐Firing Microwave Dielectric Ceramic LiCa₃MgV₃O₁₂ with Low Dielectric Loss

Abstract

Novel low temperature firing microwave dielectric ceramic LiCa3MgV3O12 (LCMV) with garnet structure was fabricated by the conventional solid‐state reaction method. The phase purity, microstructure, and microwave dielectric properties were investigated. The densification temperature for the LCMV ceramic is 900°C. LCMV ceramic possessed εr = 10.5, Qu × f = 74 700 GHz, and τf = −61 ppm/°C. Furthermore, 0.90LiCa3MgV3O12–0.10CaTiO3 ceramic sintered at 925°C for 4 h exhibited good properties of εr = 12.4, Qu × f = 57 600 GHz, and τf = 2.7 ppm/°C. The LCMV ceramic could be compatible with Ag electrode, which makes it a promising ceramic for LTCC technology application.

Preparation, crystal structure, and dielectric characterization of Li2W2O7ceramic at RF and microwave frequency range

“…Generally, the dielectric properties at microwave frequency region could be affected by several factors, including crystal structure and extrinsic factors such as pore, density, second phases, grain sizes and impurities. [17][18][19][20] In the present work, it is proposed that the main factor affecting the relative permittivity and quality factor is densification. Similar results were reported in Li 2 O-WO 3 system.…”

Microwave dielectric properties of low temperature sintering Ca5Mn4(VO4)6 ceramics

“…Phase constitution was confirmed by the XRPD and Raman results. For Ca 5 Mn 4 (VO 4 ) 6 , it is seemed that its e r is mainly affected by relative density, while its Q 9 f seems to be mainly dominated by intrinsic (packing fraction) and extrinsic (relative density) factors. The typical values of e r = 11.2, Q 9 f = 33 800 GHz (at 10.5 GHz), and s f = -70 ppm/°C were obtained for Ca 5 Mn 4 (VO 4 ) 6 ceramic at 875°C/ 5 h, wherwas the serious chemical reaction between Ca 5 Mn 4 (VO 4 ) 6 and Ag substantially affected its commercial viability for LTCC applications.…”

“…The current trend is to develop genuine low firing ceramics and the most recent investigations have explored the applicability of garnet structure compounds containing vanadium element, which show some interesting physical properties such as dielectric and luminescence [5][6][7][8][9][10]. In our previous work, the Ca 5 A 4 (VO 4 ) 6 (A = Mg, Zn, Co) ceramics sintered at below 900°C exhibited good microwave dielectric properties [11,12].…”

Microwave dielectric properties of CaV2O6 ceramics with low dielectric loss

“…Recently extensive efforts were made in V 2 O 5 -based compounds to identify novel microwave dielectric ceramic systems suitable for LTCC substrate applications since they possess low or even ultra-low sintering temperature and excellent microwave dielectric properties [3][4][5][6][7]. According to CaO-V 2 O 5 phase diagram, the melting point of CaV 2 O 6 is about 775°C [8].…”