Interactions of pulsed UV-laser with polymer surfaces: Periodic structures, functional group alignment and diamond deposition

Pulsed, polarized UV-laser irradiation of polymers at 266 and 355 nm with Nd:YAG laser source gave rise not only to periodic structures of 100 nm dimension but also functional group alignments in periodic structures which were studied with a polarized reflected FT-IR spectrophotometer. The results arising from interferance of scattered light on the surface and incoming polarized pulsed laser beams were demonstrated with poly(ethylene terephthalate), polyimides, polysulfones, polystyene and doped polyimides films. Images of polymer periodic structures were transferred to silicon surfaces by series of reactive ion etchings. Si patterns with 100 nm line and spacing with vertical wall profile were fabricated in a large area. On such Si surfaces diamond crystals were deposited from polymer plumes generated by ArF excimer laser irradiated in 193 nm on poly(methyl methacrylate). The diamond crystals deposited in this way have a very sharp Raman peak at 1332.9 cm(-1) with FWHM = 1.2 cm(-1) to 14 cm(-1) depending on location on the substrate Si wafer.