フェムト秒レーザ還元直接描画法による非平面基板上への Cu 微細構造形成

抄録

We proposed direct-writing process of Cu-based micropatterns using a combined process of spray-coating and femtosecond laser reduction of CuO nanoparticle (NP) solutions. When CuO NP solution was spray-coated on glass planar substrates in 5 s, the thickness of the center of the circular CuO NP film was 10.4 μm. The crystallinity of the micropatterns which were written by luster scanning of laser focal spot were evaluated. The micropatterns were formed at the pulse energy of 0.54 nJ and scan pitch of 5 μm, with various scan speed. When scan speed were 5mm/s and 1mm/s, the Cu-rich and Cu₂O-rich micropatterns were formed respectively. Finally, we applied this process for the fabrication of Cu-based micropatterns on nonplanar substrates. The glass tube with the diameter of 9 mm was used as the nonplanar substrates. The spray-coating time duration was 5 s. Cu-rich and Cu₂O-rich micropatterns with electrical conductivity were successfully formed by controlling the laser scan speed on nonplanar substrates.