Application of Dopant-Induced Laser Ablation to Site-Selective Modification of Sea-Island Structures of Polystyrene-black-poly(4-vinylpyridine) Films

摘要

Dopant-induced laser ablation was applied to thin polystyrene-black-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer films doped selectively with tetrakis(4-carboxyphenyl)porphine (TCPP) into the nanoscale spherical domain of P4VP-island parts. Under dry-film conditions, the ablation of the island parts was not induced. On the other hand, in methanol solvent, only the P4VP-island parts doped with TCPP were ablated selectively. The dopant-induced laser ablation is attributed to the fact that the P4VP-island parts are in the swollen state, where P4VP chains cross-linked by TCPP-dopant molecules exist with a high density in methanol. This is the first report concerning the site-selective laser ablation of diblock copolymer films.