netneut -- The Home Page of the Finishing Industry
A website for Serious Education, promoting Aloha,
& the most FUN smiley you can have in metal finishing has been free for 22 years,
but without net neutrality we could soon
cease to exist. Do us a solid, click on
the banner, and contact congress today!
topic 5952

Pitting on Pattern-Plated Copper Traces


We are seeing severe pitting on the pattern-plated copper traces, mostly near to the etches.

Our pretreatment process consists of acid cleaner, microetch & acid dip. ( etch rate 15 microinch ) we are not using anode bags but we have anode shield.

The fine line job is being affected by pitting issue. Ground area do not have any pitting problem. two months ago, we did carbon treatment for our copper bath. circulation pumps are all ok. ( no air leakage at the suction side ) we are using phosporised anode ball.

Oil free air supply is coming to our line.

Kindly help me to solve this issue.


- Singapore


The most likely cause, assuming the chemical parameters are all ok, is photoresist residues/incomplete development. Take a close look at the sidewalls of the resist and the copper surface after the developer. You might take a panel after development and microetch it, then look at the base of the resist sidewalls. If the surface was not etched, then you know you have an imaging/developer problem.

James Totter
James Totter, CEF
- Tallahassee, Florida



As Mr. Totter described, one part of the problem is in the developer. By creating sticky side walls of the resist, small bubbles attach to it easier. There is a lot of actions one can do to help minimize the problem.

1. Keep the last rinse in the developer under a pH of 7. (To terminate "after developing" )

2. Minimize the use of anti foam and maybe try another brand.

3. Run the circ. pumps in the plating bath only when not producing (depends on how heavy production pressure is).

4. Introduce a wetting agent in the pre dip (leveler)

5. Check the leveler content in the plating bath. If its too low it might increase the problem.

Peter Fogelqvist
- Sweden

This public forum has 60,000 threads. If you have a question in mind which seems off topic to this thread, you might prefer to Search the Site

ADD a Q or A to THIS thread START a NEW THREADView This Week's HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2017     -    Privacy Policy
How Google uses data when you visit this site.