MeV ion beam lithography of biocompatible halogenated Parylenes using aperture masks
Publisher DOI
Abstract
Parylenes are poly(p-xylylene) polymers that are widely used as moisture barriers and in biomedicine because of their good biocompatibility. We have investigated MeV ion beam lithography using 16O+ ions for writing defined patterns in Parylene-C, which is evaluated as a coating material for the Cochlear Implant (CI) electrode array, a neuroprosthesis to treat some forms of deafness. Parylene-C and -F on silicon and glass substrates as well as 50 μm thick PTFE were irradiated to different fluences (1×1013-1×10161×1013-1×1016 1 MeV 16O+ ions cm−2) through aperture masks under high vacuum and a low pressure (<10−3 mbar) oxygen atmosphere. Biocompatibility of the irradiated and unirradiated surfaces was tested by cell-counting to determine the proliferation of murine spiral ganglion cells. The results reveal that an oxygen ion beam can be used to pattern Parylene-C and -F without using a liquid solvent developer in a similar manner to PTFE but with a ∼25× smaller removal rate. Biocompatibility tests showed no difference in cell adhesion between irradiated and unirradiated areas or ion fluence dependence. Coating the Parylene surface with an adhesion-promoting protein mixture had a much greater effect on cell proliferation.
Date Issued
2015
Publication Type
Article
Subject(s)
Language(s)
en
Author(s)
Whitlow, Harry J. | |
Norarat, Rattanaporn | |
Jeanneret, Patrick | |
Guibert, Edouard | |
Bergamin, Maxime | |
Fiorucci, Gianni | |
Homsy, Alexandra | |
Laux, Edith | |
Keppner, Herbert |
Journal
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Publisher
Elsevier
ISSN
0168-583X
Access(Rights)
restricted