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Remanufacturing and Advanced Machining
Removal of material on the atomic scale by sputtering is used in ion beam figuring (IBF) for production of ultra-precise optical surfaces, such as spheres, aspheres,
and free forms on lenses and mirrors. Aside from finishing of optical components,
an IBF process can also be employed on molds used to produce optical lenses
(Zeuner and Kontke, 2012). Usually, diameters of machined optics can be from 5
up to 2,000 mm, though recently even 1 mm diameters became possible to process.
By means of the ion beam etching technology (IBE), feature sizes from < 100 nm
up to > 10 μm can be smoothed (Schaefer, 2018). Arnold and Pietag (2015) reported
application of ion beam figuring to further reduction of peak-to-valley (PV) sphericity error from the current 50 nm to values less than 10 nm PV with a multi-axis ion
beam figuring machine dedicated to deterministic correction of silicon spheres.
Ion beam sputtering, also called ion beam deposition (IBD), is a thin-film deposition process that uses an ion source to sputter a target material (metal or dielectric).
A typical configuration of an IBD system consists of an ion source, a target, and a
substrate. An advanced ion beam source utilizes an electron gun, so the electron
beam strikes the surface of a target and produces free ions or clusters. Sputtered species (cations, anions, or neutral particles) cool down when flying around the vacuum
chamber and deposit onto a substrate to create either a metallic or dielectric film.
Preheating substrates may improve overall performance (Kafle, 2020). When a second ion gun is used to assist the deposition by bombarding the growing film, the
method is called ion beam-assisted deposition (IBAD). Dual ion beam sputtering
can improve adhesion, density, control of stoichiometry, and low optical absorption
in thin films, while low-energy reactive ion beam bombardment can increase the
rate of compound formation, control the stoichiometry, and improve adhesion of a
deposited thin film (Teixeira et al., 2011).
The main advantages of IBD methods are attributed to the fact that the ion beam
is monoenergetic, i.e., ions possess equal energy, and highly collimated. As such,
it enables extremely precise thickness control and deposition of very dense, highquality films (Kafle, 2020).
Among novel methods based on the local sputtering of photoresist sidewalls during ion beam etching, ion beam etching redeposition is worth noting (Desbiolles
et al., 2019). This method using local sputter-redeposition is able to manufacture
multi-material 3D nanostructures of various shapes, profiles, heights, thicknesses,
and complexity. The process is simple and uses standard microprocessing tools only,
but complex nanostructures such as nanochannels, multi-material nanowalls, and
suspended networks can be successfully fabricated with features of sub-100-nm
dimensions and an unprecedented freedom in material choice. This provides an
alternative to traditional nanofabrication techniques, as well as new opportunities
for biosensing, nanofluidics, nanophotonics, and nanoelectronics.
Ion implantation is an effective technological tool for introducing single impurities into the surface layer of a substrate in order to modify or change the near-surface
chemical composition, affecting surface physical and chemical properties of materials. The degree of material surface modification depends on individual chemical and
structural properties and on implantation parameters, such as the type and energy
of an implant, current density in the ion beam, and substrate temperature. The most
critical parameter is ion dose F 0 , measured in ion/cm 2 , which determines quantity
Remanufacturing and Advanced Machining
Removal of material on the atomic scale by sputtering is used in ion beam figuring (IBF) for production of ultra-precise optical surfaces, such as spheres, aspheres,
and free forms on lenses and mirrors. Aside from finishing of optical components,
an IBF process can also be employed on molds used to produce optical lenses
(Zeuner and Kontke, 2012). Usually, diameters of machined optics can be from 5
up to 2,000 mm, though recently even 1 mm diameters became possible to process.
By means of the ion beam etching technology (IBE), feature sizes from < 100 nm
up to > 10 μm can be smoothed (Schaefer, 2018). Arnold and Pietag (2015) reported
application of ion beam figuring to further reduction of peak-to-valley (PV) sphericity error from the current 50 nm to values less than 10 nm PV with a multi-axis ion
beam figuring machine dedicated to deterministic correction of silicon spheres.
Ion beam sputtering, also called ion beam deposition (IBD), is a thin-film deposition process that uses an ion source to sputter a target material (metal or dielectric).
A typical configuration of an IBD system consists of an ion source, a target, and a
substrate. An advanced ion beam source utilizes an electron gun, so the electron
beam strikes the surface of a target and produces free ions or clusters. Sputtered species (cations, anions, or neutral particles) cool down when flying around the vacuum
chamber and deposit onto a substrate to create either a metallic or dielectric film.
Preheating substrates may improve overall performance (Kafle, 2020). When a second ion gun is used to assist the deposition by bombarding the growing film, the
method is called ion beam-assisted deposition (IBAD). Dual ion beam sputtering
can improve adhesion, density, control of stoichiometry, and low optical absorption
in thin films, while low-energy reactive ion beam bombardment can increase the
rate of compound formation, control the stoichiometry, and improve adhesion of a
deposited thin film (Teixeira et al., 2011).
The main advantages of IBD methods are attributed to the fact that the ion beam
is monoenergetic, i.e., ions possess equal energy, and highly collimated. As such,
it enables extremely precise thickness control and deposition of very dense, highquality films (Kafle, 2020).
Among novel methods based on the local sputtering of photoresist sidewalls during ion beam etching, ion beam etching redeposition is worth noting (Desbiolles
et al., 2019). This method using local sputter-redeposition is able to manufacture
multi-material 3D nanostructures of various shapes, profiles, heights, thicknesses,
and complexity. The process is simple and uses standard microprocessing tools only,
but complex nanostructures such as nanochannels, multi-material nanowalls, and
suspended networks can be successfully fabricated with features of sub-100-nm
dimensions and an unprecedented freedom in material choice. This provides an
alternative to traditional nanofabrication techniques, as well as new opportunities
for biosensing, nanofluidics, nanophotonics, and nanoelectronics.
Ion implantation is an effective technological tool for introducing single impurities into the surface layer of a substrate in order to modify or change the near-surface
chemical composition, affecting surface physical and chemical properties of materials. The degree of material surface modification depends on individual chemical and
structural properties and on implantation parameters, such as the type and energy
of an implant, current density in the ion beam, and substrate temperature. The most
critical parameter is ion dose F 0 , measured in ion/cm 2 , which determines quantity