title: Morphological investigation at the front and rear surfaces of fused silica processed with femtosecond laser pulses in air.
abstract: Different responses for the front (entrance) and the rear (exit) surfaces of fused silica processed with femtosecond laser pulses at 807 nm were observed under tight focusing conditions (NA = 0.4). The morphology of the surface in the beam path is highly sensitive to the focus position. By adjusting the focus position, we can produce not only a submicrometer cavity but also a submicrometer bubble. We achieved higher-quality micromachining and a better spatial resolution (400 nm) by focusing the laser beam at the rear surface rather than at the front surface.
authors.forename: Zhaoxin
authors.initials: Z
authors.lastname: Wu
authors.forename: Hongbing
authors.initials: H
authors.lastname: Jiang
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Zhang
authors.forename: Quan
authors.initials: Q
authors.lastname: Sun
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Qihuang
authors.initials: Q
authors.lastname: Gong