Methods of forming metal layer structures in semiconductor devices

A method of forming a semiconductor device, comprising:

• forming a first plurality of hard mask lines over a material layer on a substrate, the first plurality of hard mask lines extending along a first direction;
• forming a spacer material layer over the first plurality of hard mask lines, resulting in a second plurality of trenches extending along the first direction, each of the second plurality of trenches having sidewalls formed of the spacer material layer, wherein the second plurality of trenches tracks the first plurality of hard mask lines;
• forming a antireflective layer over the second plurality of trenches;
• forming a first line-shaped opening in the antireflective layer;
• filling the first line-shaped opening with a fill material, wherein the first line-shaped opening extends along the first direction;
• etching the spacer material layer to expose the first plurality of hard mask lines;
• removing the first plurality of hard mask lines;
• after removing the first plurality of hard mask lines, transferring a pattern of the spacer material layer and the fill material onto the material layer, resulting in trenches tracking the pattern;
• and
• filling the trenches with a conductive material.

A method of forming a semiconductor device, comprising:

• providing a workpiece having a substrate, a material layer over the substrate, and a hard mask layer over the material layer;
• patterning the hard mask layer, thereby forming a first plurality of hard mask lines;
• forming a spacer material layer over the first plurality of hard mask lines, resulting in a second plurality of trenches that tracks the first plurality of hard mask lines;
• forming an antireflective layer over the spacer material layer, including over the second plurality of trenches;
• forming an L-shaped opening in the antireflective layer, wherein the L-shaped opening includes a first line portion and a second line portion perpendicular to the first line portion, wherein the first line portion extends parallel to and is over one of the second plurality of trenches;
• filling the L-shaped opening with a fill material;
• etching the spacer material layer to expose the first plurality of hard mask lines;
• removing the first plurality of hard mask lines;
• after removing the first plurality of hard mask lines, transferring a pattern of the spacer material layer and the fill material onto the material layer, resulting in trenches tracking the pattern;
• and
• filling the trenches with a conductive material.