In high-frequency PCB substrates, vinyl-silanes mediate the critical interface between silica fillers and epoxy molding compounds. By reducing interfacial polarization through controlled hydroxyl group passivation, these coupling agents achieve dielectric losses below 0.002 at 10 GHz. Emerging applications in heterogenous integration utilize photoactive silanes to pattern adhesion layers at chiplet boundaries, enabling sub-10μm interconnects with thermal cycling reliability exceeding 3000 cycles (-55°C to 125°C).