Simultaneously enhanced thermal conductivity and dielectric properties of borosilicate glass-based LTCC with AlN and h-BN additions

Microwave devices with reduced dielectric loss and electronic components with increased integration density necessitate the higher performance of electronic packaging materials. The h-BN/AlN/CaCO3-MgO-B2O3-SiO2 -Li2CO3 glass composites were prepared via tape-casting and then sintered by pressureless and hot-pressing, respectively. The thermal conductivity of pressureless sintered composite was increased to 6.55 W/(m center dot K) by incorporating 3 wt% h-BN, and the thermal expansion of 4.47 ppm/K was achieved along with low dielectric constant of 5.76 and dielectric loss of 7.02 x 10(-4) at 24 GHz. In contrast, the hot-pressing sintered composite containing 4 wt% h-BN exhibited higher thermal conductivity of 10.3 W/(m center dot K) and lower dielectric loss of 4.77 x 10(-4). The microstructure characterization indicated the construction of heat conduction networks, and XRD analysis illustrated the formation of crystallization in the glass. Such low-temperature co-fired ceramic (LTCC) with high thermal conductivity and low dielectric loss would be a promising candidate for electronic packaging and 5G communication applications.

Automated summary

The h-BN/AlN/CaCO3-MgO-B2O3-SiO2-Li2CO3 glass composites, prepared by tape-casting and sintering, exhibit low dielectric loss and high thermal conductivity. The pressureless sintered composite with 3 wt% h-BN achieves a thermal conductivity of 6.55 W/(m·K) and a low dielectric loss of 7.02 x 10(-4) at 24 GHz. The hot-pressing sintered composite with 4 wt% h-BN demonstrates a higher thermal conductivity of 10.3 W/(m·K) and a lower dielectric loss of 4.77 x 10(-4). These composites show promising potential for electronic packaging and 5G communication applications.