Millimeter wave electromagnetic interference shielding by coating expanded polystyrene particles with a copper film using magnetron sputtering

Expanded polystyrene (EPS) particles were coated with copper by magnetron sputtering in order to produce a material suitable for electromagnetic interference (EMI) shielding. Field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray analysis (EDS) results demonstrated the effectiveness of successful copper deposition. The EMI shielding effectiveness (SE) of the Cu-coated EPS particles was measured to be 14–39 dB over a frequency range of 80–110 GHz, suggesting that Cu-coated EPS particles can be used as an effective lightweight millimeter wave EMI shielding material.