title: Influence of pyrene grafting on PMMA nanosecond laser ablation at 248 nm.
abstract: In this work, we investigate the effects of KrF nanosecond laser ablation on poly(methyl methacrylate) (PMMA) in combination with pyrene. Three materials containing PMMA were studied: (1) one doped with pure pyrene, (2) one doped with methyl 3-(1-pyrenyl)propanoate (so called alkylpyrene derivative thereafter), and (3) one grafted with pyrene. This last new material was developed by covalently bonding pyrene molecules to PMMA side-chains. A comparative study was undertaken to determine and compare the respective properties of the PMMA dye containing pyrene during nanosecond laser ablation at 248 nm. Cavities were etched for each material with up to 20 pulses for fluences between 0.03 and 1.7 J/cm(2) in samples containing 1, 2, and 4 mol % chromophore. The threshold fluences and the effective absorption coefficients were obtained. It was observed that effective absorption coefficients increased and threshold fluences decreased with the chromophore percentages in each kind of sample. Ablation parameters were not significantly modified when the dopant was changed from pyrene to the alkylpyrene derivative. On the other hand, when pyrene molecules were grafted on the polymer, the threshold fluences decreased, whereas the effective absorption coefficients became similar at fluences above 0.6 J/cm(2).
authors.affiliation: LP3 UMR 7341 and §CINaM UMR 7325, Aix Marseille Université, CNRS , 13288, Marseille, France.
authors.forename: Emeric
authors.initials: E
authors.lastname: Biver
authors.forename: Marco
authors.initials: M
authors.lastname: Berta
authors.forename: Anthony
authors.initials: A
authors.lastname: D'Aléo
authors.forename: Trang
authors.initials: T
authors.lastname: Phan
authors.forename: Sébastien
authors.initials: S
authors.lastname: Maria
authors.forename: Frédéric
authors.initials: F
authors.lastname: Fages
authors.forename: Didier
authors.initials: D
authors.lastname: Gigmes
authors.forename: Marc
authors.initials: M
authors.lastname: Sentis
authors.forename: Philippe
authors.initials: P
authors.lastname: Delaporte