A new type of spinel ceramic for CBGA package

High thermal conductivity with HITCE are highly required for microwave dielectric ceramics for CBGA electronic packaging applications. In this work, AAl2O4-x wt. % (Li2CO3-Al2O3-SiO2) (A = Zn, Mg) ceramics with spinel structure were synthesized through a conventional solid-state reaction method. The coefficient of thermal expansion of the ceramics are much higher than spinel ceramics because of the addition of Li2CO3-Al2O3-SiO2 additive. Meanwhile, the high thermal conductivity ceramics are also obtained due to the high thermal conductivity of its spinel structure and dense microstructure. Especially, ZnAl2O4-5 wt. % (Li2CO3-Al2O3-SiO2) compound exhibits thermal conductivity of 13.531 W/mK, TCE value of 8.65x10-6 K-1 (30-490 degrees C), dielectric constant of 8.40 and dielectric loss of 4.40x10-4. And MgAl2O4-10 wt. % (Li2CO3Al2O3-SiO2) compound exhibits thermal conductivity of 16.8 W/mK, TCE value of 8.9x10-6 K-1 (30-500 degrees C), dielectric constant of 7.89 and dielectric loss of 8.90x10-3. The excellent thermal and dielectric properties give it a great potential in Ceramic Ball Grid Array electronic packaging applications. (c) 2023 Elsevier B.V. All rights reserved.