Dennis James Mattson

US Patent:

6365057, Apr 2, 2002

Filed:

Nov 1, 1999

Appl. No.:

09/431445

Inventors:

Donald A. Whitehurst - Minneapolis MN
Dennis D. Mattson - Minnetonka MN
Paul D. Wyatt - St. Paul MN
Charles Ring - Eagle Bend MN
Michael J. Dufresne - Shoreview MN
Jose F. Brenes - St. Paul MN
Bruce A. Finger - St. Paul MN
David R. Zeipelt - Forest Lake MN

Assignee:

BMC Industries, Inc. - Minneapolis MN

International Classification:

H05K 300

US Classification:

216 13, 216 20

Abstract:

A process for the formation of an article having multiple electrical circuits comprises: providing a first sub-element comprising in sequence a first metal layer of copper in electrical contact with a second metal layer of aluminum in electrical contact with a third metal layer of copper; etching an electrical circuit design in the first metal layer and in a separate etch step, etching away at least 10%, but less than 100% of the second metal layer to provide electrical connections between the first metal layer and the third metal layer; etching an electrical circuit design into the third metal layer; adhering an etched surface comprising the circuit design of the first or third metal layer to a first surface of a support layer to form a circuit board. The process may etch the first and third metal layers simultaneously or sequentially. After adhering an etched surface comprising the circuit design of the first or third metal layer to a support layer to form a circuit board, an additional step may be performed, which additional step is selected from the group consisting of; a) adhering an etched surface of a second tri-metal subelement to a second surface of the support layer and b) adhering a second support layer to said third or first metal layer, respectively, and adhering an etched surface of a second tri-metal subelement to the second support layer.