ZHOU Kun ^{1, 2}, HUANG Zuzhi ^{1, 2}, HU Sijia ^{1, 2}, YING Siqi ^{1, 2}, YANG Dan ¹, LI Deliang ³, DUO Shuwang ^{1, 2}, SHI Jiang ^{1, 2}
(1. School of Materials and Energy, Jiangxi Science and Technology Normal University, Nanchang 330000, Jiangxi, China; 2. Jiangxi Province Key Laboratory of Surface Engineering, Nanchang 330000, Jiangxi, China; 3. Asset and Laboratory Management Office, Jiangxi Science and Technology Normal University, Nanchang 330000, Jiangxi, China)

Abstract: Ultra-low temperature co-fired ceramic (ULTCC) technology represents a promising avenue in the realm of electronic substrate materials. Li₂O-Al₂O₃-B₂O₃glass-ceramics, characterized by their remarkably low sintering temperature, emerges as a novel and viable material for ULTCC applications. The Li₂O-Al₂O₃-B₂O₃parent glass was synthesized via a high-temperature melting and water quenching process. A comprehensive study was conducted to elucidate the impact of Al₂O₃ on structural and dielectric properties of the Li₂O-Li₂O-Al₂O₃-B₂O₃ composite ceramics. For this study, differential scanning calorimetry (DSC), X-ray diffraction (XRD), hot stage microscopy (HSM) and scanning electron microscopy (SEM) were employed. It is revealed that an escalation in the Al₂O₃ content resulted in a marked reduction in the precipitation of the primary crystalline phases, Li₃AlB₂O₆ and Li(AlB₂O₅), within the composite materials after post-sintering at 600 ℃. Concurrently, there was a progressive diminution in the Q×f value, accompanied by an upward trend in the dielectric constant. Notably, when the Al₂O₃ proportion reached 10 wt.%, the volumetric density of the composite material, post-sintering at 600 ℃, was quantified at 2.14 kg·m⁻³, with a dielectric constant of 4.7 at 7.4 GHz and a Q×f value of 19662 GHz. These attributes underscore the potential utility of this material within the ULTCC domain.
Key words: ULTCC; alumina; aluminoborate glass ceramics; dielectric properties