<p>Sputtering is an effective technique for coating various substrates. However, the high energy involved can cause damage to polymers. In this study, polyphenylene sulfide (PPS), an engineering plastic known for its excellent thermal properties, was coated with Cu to impart electrical conductivity. To activate the PPS surface and improve Cu adhesion, oxygen plasma treatment was applied prior to deposition; its effect on deposition and electrical properties was examined. The plasma treatment facilitated the attachment of oxygen species to the PPS surface, which significantly enhanced the copper deposition rate. Notably, electrical conductivity increased by a factor of 10¹² during sputtering, with conductivity being 1.75 times greater after plasma treatment compared to untreated samples. Additionally, no detectable deterioration in the thermal or mechanical properties of the PPS was observed. These findings suggest that the plasma-assisted sputtering process enhances the electrical conductivity of PPS and has the potential to broaden its industrial applications.</p>