Surface processing of PMMA and metal nano-particle resist by sub-micrometer focusing of coherent extreme ultraviolet high-order harmonics pulses

We demonstrate sub-micrometer processing of two kinds of thin films, polymethyl methacrylate (PMMA) and metal nano-particle resist, by focusing high-order harmonics of near-IR femtosecond laser pulses in the extreme ultraviolet (XUV) wavelength region (27.2-34.3 nm) on the thin film samples using an...

Full description

Saved in:
Bibliographic Details
Published in:Optics letters 2020-05, Vol.45 (10), p.2926-2929
Main Authors: Sakaue, Kazuyuki, Motoyama, Hiroto, Hayashi, Ryosuke, Iwasaki, Atsushi, Mimura, Hidekazu, Yamanouchi, Kaoru, Shibuya, Tatsunori, Ishino, Masahiko, Dinh, Thanh-Hung, Ogawa, Hiroshi, Higashiguchi, Takeshi, Nishikino, Masaharu, Kuroda, Ryunosuke
Format: Article
Language:English
Subjects:
Ablation
Chain scission
Cleavage
Femtosecond pulses
Fluence
Harmonics
Horizontal orientation
Nanoparticles
Polymethyl methacrylate
Thin films
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We demonstrate sub-micrometer processing of two kinds of thin films, polymethyl methacrylate (PMMA) and metal nano-particle resist, by focusing high-order harmonics of near-IR femtosecond laser pulses in the extreme ultraviolet (XUV) wavelength region (27.2-34.3 nm) on the thin film samples using an ellipsoidal focusing mirror. The ablation threshold fluences for the PMMA sample and the metal nano-particle resist per XUV pulse obtained by the accumulation of 200 XUV pulses were determined to be 0.42 / and 0.17 / , respectively. The diameters (FWHM) of a hole created by the ablation on the PMMA film at the focus were 0.67 µm and 0.44 µm along the horizontal direction and the vertical direction, respectively. The fluence dependence of the Raman microscope spectra of the processed holes on the PMMA sample showed that the chemical modification, in which = double bonds are formed associated with the scission of the PMMA polymer chains, is achieved by the irradiation of the XUV pulses.
ISSN:0146-9592
1539-4794
DOI:10.1364/ol.392695