title: High aspect ratio taper-free microchannel fabrication using femtosecond Bessel beams.
abstract: We present a systematic study of femtosecond laser microchannel machining in glass using nondiffracting Bessel beams. In particular, our results identify a source and focusing parameter working window where high aspect ratio taper-free microchannels can be reproducibly produced without sample translation. With appropriate source parameters, we machine channels of 2 microm diameter and with aspect ratios up to 40. We propose the filamentation stability of the Bessel beam propagation as the critical factor underlying the controlled and reproducible results that have been obtained.
authors.affiliation: FEMTO-ST Institute, Department of Optics P.M. Duffieux, UMR CNRS 6174, Université de Franche-Comté, Besançon, France.
authors.forename: M K
authors.initials: MK
authors.lastname: Bhuyan
authors.forename: F
authors.initials: F
authors.lastname: Courvoisier
authors.forename: P-A
authors.initials: PA
authors.lastname: Lacourt
authors.forename: M
authors.initials: M
authors.lastname: Jacquot
authors.forename: L
authors.initials: L
authors.lastname: Furfaro
authors.forename: M J
authors.initials: MJ
authors.lastname: Withford
authors.forename: J M
authors.initials: JM
authors.lastname: Dudley
mesh_terms: D004867:Equipment Design / Q000379:methods; D005898:Glass / Q000737:chemistry* / Q000528:radiation effects*; D007834:Lasers; D007909:Lenses; D008422:Materials Testing; D011829:Radiation Dosage; D013499:Surface Properties