Method for fabricating bulbous-shaped vias

A method for fabricating vias on a substrate having a surface, comprising:

• disposing an etch-stop layer on said surface;
• disposing, adjacent to said etch-stop layer, a polymerizable fluid composition;
• contacting said polymerizable fluid composition with a mold with said polymerizable fluid composition conforming to a profile of said mold;
• subjecting said polymerizable fluid composition to conditions to polymerize said polymerizable fluid composition, forming a polymerized layer having a solidified indentation including a nadir and shoulders spaced-apart form said nadir, with said etch-stop layer being positioned between said surface and said polymerized layer;
• and
• defining an opening to said surface of said substrate by removing material disposed on said substrate, with said material including a sub-section of said polymerized layer positioned proximate to said solidified indentation and a sub-portion of said etch-stop layer in superimposition with said nadir.

A method for fabricating vias on a substrate having a surface, comprising:

• disposing an etch-stop layer on said surface;
• disposing a planarization layer onto said etch-stop layer;
• disposing, on said planarization layer, a polymerizable fluid composition;
• contacting said polymerizable fluid composition with a mold having a relief structure, with said polymerizable fluid composition conforming to a profile of said relief structure;
• subjecting said polymerizable fluid composition to conditions to polymerize said polymerizable fluid composition, forming a polymerized layer having a solidified bi-level indentation including a nadir and shoulders spaced-apart from said nadir, with said etch-stop layer being positioned between said surface and said polymerized layer, said etch-stop, planarization and polymerized layers, defining a composite layer;
• anisotropically etching said composite layer to form a relief pattern in said planarization layer, with said relief pattern matching a contour of said solidified bi-level indentation and having relief shoulders and a relief nadir, spaced-apart therefrom;
• selectively etching said relief pattern to expose a sub-portion of said etch-stop layer in superimposition with said relief nadir;
• and
• removing said sub-portion to expose a region of said surface in superimposition therewith.

A method for fabricating vias on a substrate having a surface, comprising:

• disposing, adjacent to said substrate, a planarization layer;
• forming, on said planarization layer, a polymerized layer having a bi-level indentation;
• and
• etching said polymerized layer and said planarization layer to expose and form a relief pattern in said planarization layer, with said relief pattern having a curved bulb extending from a region of said planarization layer proximate to said polymerized layer and terminating in a narrow waist.