Think & Tinker, Ltd.
P.O. Box 1606, Palmer Lake, CO 80133
Tel: (719) 488-9640, Fax: (866) 453-8473
Sales: Sales@ThinkTink.com, Support: Support@ThinkTink.com
Tin/Lead Electroplating Module
-Operation/Panel vs. Pattern III
- Carefully inspect the substrate for deep scratches and nicks that might impair the quality of the finished circuit.
- Format the drilling stack to minimize burr formation during drilling.
- Drill the through-holes and mounting holes, and mill/router any slot or cavity that is to be plated.
- Activate the hole-walls.
- While the ink is curing, take a few minutes to analyze the electrolyte (both the tin/lead and acid copper baths). If you have a hull cell, this is a good time to run a test to insure that the organic components of the bath (which are very difficult to test directly) are in balance and present in the proper concentrations.
- After the ink is cured, thoroughly clean both sides of the panel.
- To protect the conductive ink in the holes, it is a good idea to deposit at least 0.0002" (2 tenths, 5 microns) of copper onto the hole walls which will prevent damage during dry-film processing. To deposit the required protective layer, through-hole plate the panel with acid copper for 5 minutes to 10 minutes.
- Rinse the board thoroughly in deionized water before proceeding.
- Clean the board.
- Laminate both sides of the board with a plating grade photoresist.
- Image (and develop) both sides of the board with the desired positive circuit patterns.
Make sure to leave 0.75" bands of bare copper along each side of the board (on both sides) to act as robber bars and to provide convenient connection points for the cathode clamps.
- Dip the board into a 10% solution of sulfuric acid to make sure that no residual developing solution remains in the traces or through-holes and to minimize the introduction of contaminants into the copper plating tank.
- Attach the cathode clamp to the board, making certain that both copper surfaces have good electrical contact to the negative terminal of the plating power supply. (see fig. 9).
- Turn the power supply on.
- Lower the board into the copper plating tank.
- Swish the board gently back and forth to drive any trapped air bubbles out of the through holes.
- Turn on the air compressor and adjust the air flow until a uniform blanket of agitation roils the top of the bath on both sides of the board. You only need about 2 CFM (Cubic Feet per Minute) of air flow per square foot of bath surface.
- Slowly ramp up the current (take about 20 sec.) to the value C calculated above.
- Plate the board for ½ the total copper plating time (TC, refer to your copper plating manual for the method of calculating this value).
Sales: 1-(719) 488-9640 Tech Support: 1-(719) 488-9640 Fax: 1-(866) 453-8473
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Updated 2/13/2014 8:36:58 AM