title: Nonlinear microscopy techniques for assessing the UV laser polymer interactions.
abstract: A new diagnostic approach for assessing the in-depth laser induced modifications upon ultraviolet polymer irradiation is presented. The methodology relies on the observation of morphological alterations in the bulk material (Paraloid B72) by using third harmonic generation. This non destructive methodology allows the detailed and accurate imaging of the structurally laser modified zone extent in the vicinity of the irradiated area. Additionally, for the first time, the visualization and quantitative determination of the contour of the laser-induced swelling/bulk material interface is reported. The observed polymer surface swelling following single-pulse KrF laser irradiation at sub-ablation fluences is interpreted in the context of a model for laser-induced bubble formation due to droplet explosion mechanism.
authors.affiliation: Institute of Electronic Structure and Laser, Foundation for Research and Technology (FORTH), P.O. Box 1385, Heraklion, 71110, Greece. selimis@iesl.forth.gr
authors.forename: Alexandros
authors.initials: A
authors.lastname: Selimis
authors.forename: George J
authors.initials: GJ
authors.lastname: Tserevelakis
authors.forename: Sotiria
authors.initials: S
authors.lastname: Kogou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Pouli
authors.forename: George
authors.initials: G
authors.lastname: Filippidis
authors.forename: Natalia
authors.initials: N
authors.lastname: Sapogova
authors.forename: Nikita
authors.initials: N
authors.lastname: Bityurin
authors.forename: Costas
authors.initials: C
authors.lastname: Fotakis