Vishay EFI offers a variety of substrates for custom thin film solutions. The three substrates mainly used in our custom solutions are Alumina (Al2O3), Aluminum Nitride (AlN) and Beryllium Oxide (BeO) either lapped, as-fired or polished surface finishes. Alumina is a cost-effective solution that is commonly used for its surface quality and high frequency performance.
For power applications and when high thermal conductivity is needed, AlN and BeO substrates are optimal. Important factors to consider when choosing a substrate include dielectric constant, surface finish, loss tangent, thermal conductivity, coefficient of thermal expansion and cost. Vishay EFI produces on substrates that range in thickness from 5 mils to 60 mils and range in size from 20 x 20 mils to 4.50 in x 4.50 in.