Summer 1990
Superior Fine Line Etchants
With the advent of tighter pollution control requirements,
manufacturers are looking for improved processes that will not
only perform the necessary functions in the manufacturing
operation, but will also be easier to waste treat and will require
lower capital equipment expenditures to meet pollution
requirements.
Among the processes that meet the above requirements is
hydrogen peroxide-sulfuric acid based etchants to replace ferric
chloride and alkaline etchants used for final etching.
Peroxide-sulfuric etchants are relatively new. These etchants
offer several advantages in terms of reduced waste treatment,
improved atmosphere in the etching room, and considerable
savings when recovery of the etched copper is employed.
Michael Carano, Electrochemicals