Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9818208 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2005 | 6 Pages |
Abstract
We have investigated the mechanism of high rate erosion which is observed when polytetrafluoroethylene (PTFE) is exposed to MeV protons in an oxygen rich atmosphere (e.g. air). Using currents of the order of nA, it is possible to create holes with depths of millimetres and diameter defined by the beam area on the surface with exposure times of minutes. This is not observed in atmospheres of nitrogen, helium or argon nor in vacuum. We propose that the erosion is a result of the formation of a stable gaseous compound following beam induced decomposition of the PTFE (possibly an acyl fluoride) which does not re-deposit in the hole. We present the results of experiments leading to this hypothesis and propose a method for fabricating three-dimensional structures in PTFE with micrometre feature size. This process is the subject of an international patent application.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
G.W. Grime, C.J. Sofield, I. Gomez-Morilla, R. Gwilliam, M.D. Ynsa, O. Enguita,