The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 1989
Filed:
Jun. 28, 1985
David J Lando, Allentown, PA (US);
Frederick R Wight, Jr, West Millington, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
Printed circuit boards having a plurality of circuit layers are produced using a specific processing sequence. A copper-clad substrate is first patterned in a desired configuration to produce the first layer of the printed circuit board. The patterned metallization is then covered with a specifically formalated energy sensitive material. The energy sensitive material is delineated in a desired pattern and developed to uncover portions of the underlying metallization pattern. The entire substrate is blanket-cured to produce a rigid layer having openings in appropriate places. The openings are metallized and a second copper pattern is produced on the cured polymer by conventional metallization and lithographic techniques. If desired, the process is repeated until a suitable number of copper patterned levels are obtained.