Influence of hBN content on dielectric properties of calcium silicate for high-frequency substrate application

We report a method for the fabrication of multilayer calcium silicate (Sc) ceramic composite containing 1, 3, and 5 wt. $$\%$$ of hexagonal boron nitride (hBN). The multilayer ceramic tapes were engineered using aqueous tape casting, laminating process, and pressureless sintering at 1050  $$^{\circ }$$ C in an argon atmosphere. The structural and dielectric properties of the multilayer hBN-doped Sc ceramic tapes were investigated through several characterization techniques. We observed a stable behavior of the relative dielectric constants (1.99–2.22 range) for the multilayer hBN-doped Sc ceramic tapes at high-frequency regime. Also, we verified a considerable reduction of the dielectric losses of around 20 $$\times $$ as the amount of hBN increases. Our results show that multilayer hBN-doped Sc ceramic tapes are promising candidates for high-frequency substrate applications.