Lift off process for conductor foil layer

Abstract

A flex-circuit or a rigid printed circuit board is formed by depositing an adhesive pattern on a top surface of a substrate. The adhesive pattern corresponds to a copper foil pattern to be formed for interconnecting electronic components. A thin copper foil is then laminated over the substrate to adhere the foil to the adhesive pattern. The foil is then peeled off the substrate such that the foil overlying the adhesive pattern remains, and the foil that is not overlying the adhesive pattern is removed. In one embodiment, the foil is cut or weakened along the edges of the adhesive pattern to minimize tearing of the foil. The foil may be first affixed to a sheet for increased mechanical integrity, prior to the foil being laminated over the substrate, followed by kiss-cutting the foil while on the sheet to avoid tearing of the foil during the lift-off step.

Dependencies are inferred from the claim text.