Process for high density interconnection of substrates and integrated circuit chips containing sensitive structures
AssigneeMartin Marietta Corporation
InventorsHerbert S. Cole, Theresa A. Sitnik-Nieters, Bernard Gorowitz
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Abstract
In a method for preserving an air bridge structure on an integrated circuit chip used in an overlay process, a patternable protective layer is applied for providing mechanical strength to prevent deformation during subsequent processing. A polymeric film layer is applied over the chip and protective layer, and interconnections are fabricated through the polymeric film layer. The polymeric film layer is removed from the area over the air bridge structure. The patternable protective layer is then removed, leaving the resultant structure with an undamaged air bridge which is free of residue.
Claims30
A method for preserving a sensitive structure on an integrated circuit chip which, when exposed to polymer lamination, would deform, having chip pads thereon and supported by a substrate, comprising the steps of:
- applying a solvent-removable protective layer over said sensitive structure to support said structure on all sides, wherein said protective layer does not significantly change solubility characteristics upon exposure to temperatures of about 260.degree. C.;
- applying a high density interconnect polymeric layer over said chip and said substrate;
- providing at least one via in said polymeric film layer aligned with a predetermined one of said chip pads;
- providing a pattern of electrical conductors on said polymeric film layer extending through said at least one via and interconnecting said chip in a circuit;
- removing said polymeric film layer from the area over said sensitive structure;
- and
- removing said solvent-removable protective layer.
A method for preserving an air bridge structure on an integrated circuit chip having chip pads thereon, comprising the steps of:
- applying a solvent-removable protective layer over said air bridge structure to support said structure on all sides, wherein said protective layer does not significantly change solubility characteristics upon exposure to temperatures of about 260.degree. C.;
- positioning said chip on a substrate;
- applying a polymeric film layer over said chip and said substrate;
- providing vias in said polymeric film layer aligned with predetermined ones of said chip pads;
- providing a pattern of electrical conductors on said polymeric film layer extending through said vias for interconnecting said chip in a circuit;
- removing said polymeric film layer from the area over said air bridge structure;
- and
- removing said protective layer.
A method for preserving an air bridge structure on an integrated circuit chip having chip pads, comprising the steps of:
- applying a solvent-removable protective layer over said air bridge structure to support said structure on all sides, wherein said protective layer does not significantly change solubility characteristics upon exposure to temperatures of about 260.degree. C.;
- positioning said chip in a substrate;
- applying a polymeric film layer over said chip and said substrate;
- providing vias in said polymeric film layer aligned with predetermined ones of said chip pads;
- providing a pattern of electrical conductors on said polymeric film layer extending through said vias for interconnecting said chip in a circuit;
- removing said polymeric film layer from the area over said air bridge structure;
- and
- removing said protective layer.
Dependencies are inferred from the claim text.