Shigeru KATAYAMA^1,2,*, Mika HORIIKE^2,3, Masakatsu URAIRI², Kazuyuki HIRAO³ and Naoto TSUTSUMI^1,*

¹Department of Polymer Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-8585, Japan
²Core Technology Center, Nitto Denko Corporation, 1-1-2 Shimohozumi, Ibaraki, Osaka 567-8680, Japan
³Photon Craft Project, Japan Science and Technology Corporation, Keihanna Plaza Super-Lab. 2-6, 1-7 Hikaridai, Seika-cho, Kyoto 619-0237, Japan

(Received December 16, 2002; Accepted April 18, 2003)

The upheaval structure on the surface of polymer induced by the irradiation of a near-infrared (NIR) femto-second laser pulse in polymer bulk was investigated. Copolymers, such as poly(acrylonitrile-styrene) (AS) and poly(acrylonitrile-butadiene-styrene-methyl methacrylate) (ABSM) produced upheaval structures with a flattop just like the crater of a volcano, whereas homopolymers with relatively high glass transition temperature (T_g), such as polycarbonate (PC) and polyether imide (PEI) were more often formed a bell-shaped upheaval structure. A micro-lens effect was observed for the bell-shaped upheaval structure, but that effect was not observed in the case of copolymers with a flattop structure. Replication of the bell-shaped upheaval structure in PC was carried out by electroforming (non-electrolytic plating of Ni and the following electrolytic plating of Ni) and potting approximately 30 wt% THF solution of AS copolymer. A micro-scale bell-shaped upheaval structure in PC induced by a laser pulse was replicated using a Ni mother mold with suitable precision, and the replicated bell-shaped structure also showed a micro-lens effect.

Key words: femto-second laser, induced structure, replication, electroforming molding

^*To whom all correspondence should be addressed.