Plasma etch method for forming metal-fluoropolymer residue free vias

Abstract

A plasma etch method for forming a patterned silicon containing dielectric layer within a microelectronics fabrication. There is first provided a plasma reactor chamber. There is then fixed within the plasma reactor chamber a microelectronics fabrication. The microelectronics fabrication comprises: (1) a substrate employed within the microelectronics fabrication; (2) a metal layer formed over the substrate; (3) a silicon containing dielectric layer formed upon the metal layer; and (4) a patterned photoresist layer formed upon the silicon containing dielectric layer. There is then etched through use of a plasma etch method at a first plasma reactor chamber pressure while employing the patterned photoresist layer as a photoresist etch mask layer the silicon containing dielectric layer to form a patterned silicon containing dielectric layer while reaching and etching the metal layer to form an etched metal layer. The plasma etch method employs an etchant gas composition comprising a fluorine containing etchant gas. Finally, there is pumped the plasma reactor chamber to a second plasma reactor chamber pressure lower than the first plasma reactor chamber pressure for a time sufficient to attenuate formation of a metal-fluoropolymer residue layer upon the etched metal layer.