[19p-A404-1~19] 3.7 Laser processing

△ [19p-A404-18] Effect of Silver on Photopolymerization in Femtosecond-Laser-Based Fabrication of PDMS/Silver Composite Microstructure

〇Akito Katayama¹, Yasutaka Nakajima², Mitsuhiro Terakawa^1,2 (1.Keio Univ., 2.Grad. Sch. Keio Univ.)

Keywords:femtosecond laser, PDMS, laser direct writing

In this study, we investigate the effect of silver on femtosecond-laser-based fabrication of PDMS/silver composite microstructures. For the investigation, we compared the fabrication threshold and line widths of PDMS/silver composite and PDMS line structures fabricated by femtosecond laser irradiation of a PDMS/silver ions mixture and a PDMS solution for each. The fabrication threshold and line widths of the structures were obtained by changing laser power. The fabrication threshold of PDMS/silver composite structures was lower than that of PDMS structures, which suggested that simultaneous photopolymerization and photoreduction could be induced at lower laser power in comparison with photopolymerization. This could be related with silver nanoseeds which could be generated during the formation of PDMS/silver composite structures. Besides, at the same laser power the line width of the PDMS/silver composite line structure was narrower than that of the PDMS line structure, which could be attributed to silver ions in the mixture. We expect this novel approach of the formation mechanism of the polymer/metal composite structures will lead to investigation of the relation between values such as irradiation conditions, the amount of silver in a fabricated structure, and the structural size. This study will also contribute to fabrication of polymer/metal composite structures with desired optical/electrical properties and functions.