Metal Etchant


Au (Gold) Etchant

AT-409 is an etchant exclusively developed for Au (Gold) deposition of semiconductor wafer. AT-409 is a neutral type etchant which has only few or no reactivity to other metal except gold, so the product is mainly used for wafer pattern etching. Its application method is simple, residue is not left on the wafer surface after treatment, and its quality is outstanding without damage on patterns. AT-409 is developed considering effects on human body and environment, and does not corrode material and facilities.


• As an eco-friendly etchant, it minimizes effects on human body, environment, and facility
• Minimum reactivity to other metal except gold
• Provides outstanding product quality without residue on the wafer surface after etching
• Simple application method → excellent productivity
• Etching rate is controllable by controlling temperature and concentration [E/R: 100Å / sec (60℃)]

[ Properties and method ]

Appearance Dark brown transparent liquid Concentration Original/undiluted
Odor Unique odor Temp. Room temp. ~ 60℃
pH(10%) 7.0 ± 0.5 Method Dipping, spray
S/G (g/ml) 0.95 ± 0.02 Packing 20L (pail)  /  200L (drum)

[ Processing procedure ]

[ Etching result ]

Before After