High Performance EMI Shielding Materials and Spraying Process Parameters for High Frequency FCBGA Application

In order to apply silver (Ag) epoxy composites to the FCBGA, we investigated how a variety condition of Ag epoxy composites such as curing temperature, Ag contents, and film thickness effects the electrical resistivity of shielding layer formed by Ag epoxy composites and the series resistance of FCBGA package's daisy chain connected by shielding layer. The resistivity and the series-resistance were more affected by the curing temperature than the curing time. It was found that the optimized Ag contents was 91~92%. With the 91~92% Ag contents, the resistivity showed 3.5×10^5 ?·cm and 21m? of the series-resistance of daisy chain, respectively. We found that the tendency of the resistivity was the same to that of series-resistance of daisy chain. Additionally, we investigated the electrical properties of AgCu epoxy composites.