Improved shielding performance using high permeability electroplated thin films in printed circuit boards

Abstract

The application of electroplated magnetic materials for improved shielding of inductive coil structures produced using printed circuit board (PCB) technology is demonstrated. In this way, the range of shielding materials available for use in PCB as a replacement for ferrite is increased, so that a wider range of applications can be addressed and practical issues associated with the need for attachment and brittleness of ferrite are eliminated. A comparison of shielding performance of four different soft magnetic alloys is presented. The performance of different thicknesses and permeability of electroplated materials is compared in terms of coil inductance and shielding effectiveness (SE). Simulations and measurements show that the proposed alloy materials can provide inductance enhancement of inductive coils in PCB by a factor of over 1.4, while matching the SE levels of ferrite. © 2011 IEEE.