RF Property Variations on Plastic Packaging Due to Molding Compound Effects

We compared the RF behaviors on a typical plastic packaging (100-lead PQFP) due to molding compound effects in this study. To this end, a testing fixture was first designed to cooperate the measurement on an Agilent 4287A RLC meter. The PQFP samples, both with and without molding compounds, were prepared afterward. Inductances and capacitances on the leads of the testing samples under microwave frequency operations were next measured and compared, respectively. It is concluded from the first measurements that the molding compound in a packaging will raise the capacitance values but it will not affect to the inductance of a packaging lead to bond wire under RF frequency.