Process Hierarchy

If you are interested in this process, either by itself or as part of a longer processing sequence, please send us email at engineering@mems-exchange.org or call us at (703) 262-5368
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  Nickel LIGA (fully released structures) (PMMA)
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  1 Titanium E-beam evaporation
Materialtitanium
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  2 Gold E-beam evaporation
Materialgold
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  3 Titanium DC sputtering
Materialtitanium
  4 Titanium surface treatment
Depth100 nmMaterialtitanium
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  5 X-ray photolithography (front-front align) (PMMA)
  5.1 PMMA resist sheet bonding
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  5.2 Surface fly-cutting
Materialphotoresist (category)
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  5.3 X-ray front-front align
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  5.4 X-ray exposure
MaterialPMMA
  5.5 Photoresist develop (PMMA)
MaterialPMMA
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  6 Plating preparation (descum)
MaterialSU-8
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  7 Nickel electroplating (sulfamate)
Materialnickel
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  8 X-ray flood exposure w/o mask (PMMA)
MaterialPMMA
  9 Photoresist develop (PMMA)
MaterialPMMA
  10 Titanium wet etch
Materialtitanium
Process characteristics:
Nickel thickness
Nickel thickness*
must be 0 .. 500 µm
0 .. 500 µm
Resist thickness
Resist thickness*
must be 0 .. 1000 µm
0 .. 1000 µm
Gold thickness 0.1 µm
Mold deviation across height 2 µm
Mold height uniformity 10 µm
Mold sidewall roughness 200 nm
Release layer thickness 3 µm
Smallest feature size 5 µm
Titanium thickness 0.01 µm
Wafer size
Wafer size
Comments:
  • This LIGA process is used to
    make Ni structures that are
    completely released from the
    handling substrate at the end
    of the process.
  • Application examples: Gear
    wheels and microsprings.
  • Pricing available upon request.
  • Process requires an X-ray
    mask. Please refer to
    'Mask-making' section.
  • Process is confined to a 2"
    diameter area.