Design of high density structures with laser etch stop
AssigneeInternational Business Machines Corporation
InventorsCharles R. Davis, Frank D. Egitto, Eugene R. Skarvinko
Life of this patent
Estimating the term…
Abstract
A multi-layer electronic circuit package including at least one electrically conductive plane, a first organic polymeric dielectric material having a first optical absorbency to an ablating wavelength of laser light, and a second organic polymeric dielectric material having a second optical absorbency to the ablating wavelength of laser light. The first and second optical absorbencies being different from each other. A first layer of one of the organic polymeric materials overlays at least one surface of the at least one electrically conductive plane and a second layer of a different organic polymeric material with a different optical absorbency to the material in the first layer overlays the first layer.
Claims7
A method of forming a multi-layer electronic circuit package, wherein at least one layer of the multi-layer package includes an electrically conductive plane with an organic, polymeric dielectric deposited on major surfaces thereof, said method comprising the steps of:
- a) depositing a first layer of a first organic polymeric dielectric material on a major surface of the conductive plane, said first organic polymeric material having a first optical absorbency to an ablating wavelength of laser light;
- b) forming circuitization, including lands, on said first layer of organic, dielectric material;
- c) depositing a second layer of a second organic, polymeric dielectric material atop said circuitized first layer, said second organic polymeric material having a second optical absorbency different than said first optical absorbency of said first layer at a laser ablating wavelength;
- and
- d) laser ablating a via through said second layer to said circuitization at said laser ablating wavelength.
Dependencies are inferred from the claim text.