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Injection-Molded Inner Plane Circuit Board

IP.com Disclosure Number: IPCOM000102564D
Original Publication Date: 1990-Dec-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 39K

Publishing Venue

IBM

Related People

Mirre, MW: AUTHOR

Abstract

Disclosed is a simple method of manufacturing the substrate of an inner plane circuit board by combining insert injection molding and multiple shot injection molding.

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Injection-Molded Inner Plane Circuit Board

       Disclosed is a simple method of manufacturing the
substrate of an inner plane circuit board by combining insert
injection molding and multiple shot injection molding.

      The process begins with the insert injection molding. The
insert is the desired inner plane circuit pattern. Referring to the
cross-section view shown in the figures, the circuit can be made of
conductive foil 10 overlaid on a polymer film 11 (equal or similar to
the molding polymer compound) or of similar make up.  The circuit
pattern is placed into the mold and closed.  The molding resin 12 is
then injected into the mold, covering one side of the circuit insert
10.  This molding can include via holes to 13 or through 14 the inner
plane circuitry.  These would be created via details in the mold.

      The other side of the inner plane is covered with resin 15 by
using a second injection from a molding machine.  This can be
accomplished on a traditional two-shot molding machine and retracting
cavity mold or by removing the inner plane/resin combination from the
first mold and placing it in a second mold and molding machine.

      Circuitry can be placed on the outer surface of the circuit
board and into the via holes by using a mask and plasma treatment
process or a variety of other methods.  The method, however, can be
dependent on the resin used in molding.