AU etch 200

Gold Etchant

General Information

Au etch 200 is a non-hazardous, cyanide-free, slightly alkaline etchant for Au. The etchant is used for the wet-chemical patterning of Au layers with selectivity to metals like Pt, Ni, Cr, Ti, Al. Common areas of use for semiconductor fabrication or microsystem technology.


  • Low undercut (in the range of the layer thickness), minimum feature size < 1μm
  • Selectivity to many materials, e.g. common metals used in electroplating industry
  • Available in different purity grades
  • Compatible to resist masking
  • Not hazardous substance and easy to handle


Au-etch-200 is compatible/etches selective to following materials:

  • Resists: common Novolak as masking resist (e.g. AZ® Photoresist)
  • Metals: no attack on Cr, Pt, Ni, Ti, Ta, Al; Cu is attacked
  • Semiconductor materials: Si, SiO2, Si3N4
    (further information an request)

Etching rate

Under normal condition, the etching rate is around 40nm/min (at 50°C). The mixed etching solution is stable over time and can be used multiple times depending on the requirements of application. It is recommended to dispose the solution at the latest, when the etching rate has changed by 20%.

Technical Data Sheet:

For further information please refer to the technical data sheet:
> AU etch 200 (TDS)
Wet Etching
> Wet etching metals

Sales Volumes, Purity Grade and Shipping

Available Sales Units:

  • Bottles á 5 L or 1 L 

Our typical lead time is 1-3 working days within Germany, lead times to other countries on request. On demand, in urgent cases our etchants can be shipped within 24 hours to a destination inside Germany.

Please send us your request.

e-mail: sales(at)
phone: +49 (0)731 977 343 0
fax: +49 (0)731 977 343 29

Thank you very much for your interest!

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