Cr-mask Etching

 

Cerium ammonium nitrate Ce-(NH4)2-(NO3)6	200g
Acetic acid (glacial) CH3COOH 98%	35ml
Adding Deionized Water	-
total	1000ml

Dissolve the acid in 700ml of DI water.

Then add the Ceric ammonium nitrate and stir for about 10min until the solution is almost clear.

Now add the remaining water to make 1000ml.

 

If the water has not been acidic before the adding the ceric ammonium nitrate then a precipitate is formed which cannot be removed by filtering.

 

The etchant should be filtered before use.

 

Any drying of blanks during processing should be avoided.

 

Rinse at least 2 minutes in running DI water or 50sec DI water spray after etching.