Try 10 mls ammonium hydroxide (ammonia)
     10 mls water
     10 drops 35% hydrogen peroxide
swab on the section 5-8 times with a cotton-tipped swab and rinse
immediately with cold water.  If you immediately dip the section in an
antitarnish, you can keep the copper from staining.  If you need better
contrast between the copper and the solder (for photographs) you can
dip the section in 25% v/v nitric acid prior to the antitarnish - this will turn
the solder dark.

The etch solution will last for only an hour or two before it no longer is
effective.

>>> "Eltek Ltd. - Process Engineering"
<[log in to unmask]> 03/19/98 07:11am >>>
Hi !
What is the composition of solution for microetching  of crosssections to
show the borders between copper layers ?
Edward Szpruch
Eltek Ltd - Israel
Tel  972 3 9395050
Fax 972 3 9309581
E-mail :  [log in to unmask]

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