Showing papers on "Electroless nickel plating published in 1967"

High speed additive circuit process

Abstract: A HIGH SPEED ADDITIVE CIRCUIT PROCESS FOR MANUFACTURE OF CIRCUIT LINES UPON A POLYESTER OR POLYIMIDE SUBSTRATE, INCLUDING THROUGH-HOLES THEREIN, COMPRISING THE STEPS OF CLEANING, SENSITIZING, ACTIVATING, PRINTING A NEGATIVE FACSIMILE, OF THE FINAL DESIRED PATTERN OVER THE ACTIVATED SURFACE, HEAT SETTING, ELECTROLESS NICKEL PLATING, CURING, AND FINAL CONDUCTIVE COATING BY FLOW SOLDERING. ONLY ONE STEP MAY EXCEED ONE MINUTE IN TIME. TEMPERATURES AND TIME AT TEMPERATURE DETAILS ARE INCLUDED. CONDUCTIVE LINES AS FINE AS 2 MILS WIDE ON 4 MIL CENTERS MAY BE MADE BY THIS PROCESS.

Room temperature electroless nickel plating bath

Abstract: A PROCESS FOR DEPOSITING NICKEL ONTO A SUBSTRATE FROM A ROOM TEMPERATURE ELECTROLESS PLATING BATH; THE BATH INITIALLY INCLUDES (I) A NICKEL SALT, (II) SODIUM HYPOPHOSPHITE, (III) SODIUM PYROPHOSPHATE, AND (IV) AMMONIUM HYDROXIDE. THE CONCENTRATION OF AMMONIUM HYDROXIDE IS CHOSEN SO AS TO ADJUST THE PH OF THE BATH TO AN INITIAL VALUE (BETWEEN 9.0 AND 11.5) CORRESPONDING TO THE DESIRED PLATING RATE. A STRONG BASE SUCH AS SODIUM HYDROXIDE IS THEN ADDED TO INCREASE THE PH OF THE BATH ABOVE THE INITIAL VALUE WITHOUT SUBSTANTIALLY AFFECTING THE PLATING RATE. IN USE, THE PH OF THE BATH DECREASES, BUT THE PLATING RATE REMAINS RELATIVELY UNAFFECTED SO LONG AS THE PH DOES NOT DROP BELOW THE INITIAL VALUE SET BY THE AMMONIUM HYDROXIDE. THIS PERMITS WIDER TOLERANCES IN PH CONTROL OF THE BATH AND ALLEVIATES THE NEED FOR ADDING AN ACCURATELY CONTROLLED AMOUNT OF HYDROXYL ION WHEN THE BATH IS REGENERATED.