Hello again,

I'm not sure about the purpose of your experiment.  If the purpose is to
test the adhesion of photo resist, immersion won't tell you much.  If you
want to study the etch rate, this works.  You might be able to get the
relationship curve of etch rate versus Cu++ concentration in the etchant
over time.  Just remember the curve shapes like a bell.  The etch rate
is very slow in fresh etchant.  As the Cu++ builds up, the etch rate picks
up.  After certain point etch rate goes down due to high Cu++.  That's
where you want to replenish.  Let me know if you need more information.

Yu-Shan Han
Lead One Technology, Inc.
(206)368-8429

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Meigs, Jonathan
Sent: Wednesday, May 26, 1999 11:53 AM
To: [log in to unmask]
Subject: Re: [TN] Ammoniacal Etchant Recipe


Thanks for the replies, and the reminder to be specific.
I would much prefer to immerse the samples for etching (they are about 3" by
5").

If necessary, I could build a small spray etcher, I suppose, but maintaining
temperature of a small volume of etchant recirculating after spray might be
a challenge.

Any recommendations are most welcome, and again thank you for the advice.

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