Laser-assisted liquid-phase etching of copper conductors
AssigneeMicroelectronics and Computer Technology Corporation
InventorsRobert F. Miracky, Kantesh Doss, Bryan Seppala
Life of this patent
Estimating the term…
Abstract
A process for laser-assisted liquid phase etching of copper conductors which includes the use of a solution of sulfuric acid and hydrogen peroxide in contact with an integrated circuit substrate and the provision of a laser beam to select substrate areas having copper conductors to be etched. Also disclosed is an apparatus for the laser-assisted etching.
Claims19
A process for laser-assisted liquid-phase etching of copper conductors, comprising the steps of:
- immersing a substrate having copper conductor lines on a dielectric in an etchant solution comprising sulfuric acid and hydrogen peroxide;
- and
- irradiatig select copper lines at select areas with a focused laser beam to etch said lines at said select areas.
A copper etchant solution for etching copper in monolithic medium film multi-chip substrates, comprising about two percent per volume sulfuric acid and about one percent per volume hydrogen peroxide.
An apparatus for laser-assisted liquid-phase etching of integrated circuit copper conductors, comprising:
- means for providing a visible wavelength laser beam;
- shuttering means for shuttering said laser beam;
- a beam expander;
- a sample holder for receiving and retaining a workpiece;
- a microscope head positioned adjacent said workpiece;
- means for positioning during operation said microscope head relative to said workpiece;
- a first port having one end attached to said microscope head for receivng said laser beam and introducing said beam into said microscope head;
- a second port also attached to said microscope head for mounting a video camera;
- a third port also attached to said microscope head for introducing illumination to said sample holder;
- and
- computer means for positioning said sample holder in its x-y plane relative to said microscope head.
Dependencies are inferred from the claim text.