High-k and ultra-low-loss BADCy/Ni0.5Ti0.5NbO4 composites for PCB application fabricated by cold isostatic pressing and vacuum assisted infiltration processes

A simple method, which include cold isostatic pressing and vacuum assisted infiltration, that can significantly improve the filler content, was employed to fabricate Bisphenol-A cyanate ester resin (BADCy)/Ni0.5Ti0.5NbO4 composites with high-k and ultra-low-loss. Results show that briquetting pressure and sintering temperature for fabricating Ni0.5Ti0.5NbO4 porous preforms have a great influence on the properties of BADCy/Ni0.5Ti0.5NbO4 composites. The optimal process for the fabrication of BADCy/Ni0.5Ti0.5NbO4 composites is fixing the briquetting pressure at 90 MPa and sintering temperature at 700 °C. The dielectric constant and loss of the composites are 22.79 and 4.17 × 10−3 at 9041 MHz, respectively. Properties of this kind of composites can meet the requirements for high-k and ultra-low-loss PCB application.