What is the Difference Between Electron Beam Deposition & Magnetron Sputtering?
March 27, 2019
By Dan Fiore, Director of Business Development
A regular question we
get here at NACL is “what is the difference between electron beam and Magnetron
Sputter deposition. Both processes have their advantages and disadvantages
depending on the coating type, substrate material, application, and test requirements
(both mechanical and optical). This quick post should help outline the
technologies and help you make an educated decision in which process is most
beneficial for your program.
Electron Beam Vacuum Deposition (E-Beam)
When utilizing an electron
beam deposition process (E-Beam), source materials in a coating chamber are
either vaporized using heating or electron-beam bombardment of powder or
granular substances. The subsequent vapor condenses upon the optical surfaces,
and via precision computer control of heating, vacuum levels, substrate location,
and rotation during the deposition process result in conformal optical coatings
of pre-specified optical thicknesses. E-Beam coatings can be enhanced using an Ion
Beam to assist the deposition procedure. In an ion assisted coating, an ion
beam within the vacuum chamber is aimed at the substrates and the substrates
are bombarded with this ion beam prior to deposition of the evaporative
materials. The result of this bombardment is an increase in the adhesion energy
of the material to the substrate which creates an optical coating with a denser
and more robust bond that may also less stress.
E-Beam coatings are
advantageous for polymeric coating due to its simplicity and flexibility. E-Beam coatings also process in a more rapid fashion in a batch
scenario as compared to Magnetron Sputtered coatings which make them ideal for
high volume commercial applications. An additional benefit of E-Beam coatings
is a wider array of less expensive evaporative materials. Magnetron sputter
targets are traditionally far more expensive than the evaporative materials
used in the E-Beam process.
Magnetron sputtering is a deposition
technology involving a vapor/gas plasma which is produced and confined to the
same space as the desired deposition material or the evaporative target. The
surface of the target is bombarded by high-energy ions within the plasma, and
the atoms which come free from the target bombardment process travel through
the vacuum chamber in order to be deposited onto a substrate. When the loose
atoms are deposited onto the desired substrate, they form a thin-film.
Magnetron sputtering is advantageous
as it doesn’t require evaporation or melting of source materials, allowing for
exotic material experimentation and novel coating film applications.
North American Coating
Laboratories utilizes E-Beam coating technology as we have found it is
perfectly tailored to our primary expertise which is applying high-performance optical
coatings to polymeric optical elements at room temperature. Magnetron Sputter
coating has many advantages, but our custom designed processes benefit greatly
from the low energy, quick cycle times of the E-Beam coating process.
We’d love to chat more
about your program and see if our coating solutions are a fit for your
application. Please give us a call so we can help you with your decision as to
which process is most beneficial for your program.