Toshihiro Yokogawa, Ichiro Takano
With the increasing functionality of mobile devices, their components are required to operate reliably at high frequencies. Consequently, the selection of materials for printed circuit boards has become limited, and polytetrafluoroethylene (PTFE) has emerged as a promising candidate due to its low dielectric loss. In this study, we investigated the surface chemical state affecting the adhesion between PTFE and Cu thin films by varying the irradiation angle and dose of H3+ ion beams to PTFE. The ion irradiation was performed at incident angles of 0°, 45°, and 60° with an acceleration voltage of 10 kV. The primary objective of this work was to examine the surface morphology and chemical states of PTFE after irradiation, which are closely related to its adhesion properties. At irradiation angles of 45° and 60°, temporary surface smoothing was observed at specific irradiation dose. XPS measurement also revealed a decrease in water contact angle, indicating increased hydrophilicity associated with the formation of surface C-H bonds.