Semiconductor device with a metal line and method of forming the same

A method of forming a metal line in a semiconductor device, comprising:

• forming a first insulation layer and a first etch stop layer on a conductive layer, and forming a first photosensitive layer pattern on the first etch stop layer;
• forming a first opening for a via hole by etching the first etch stop layer using the first photosensitive layer pattern as a mask;
• forming a second insulation layer and a second etch stop layer on the first insulation layer and the first etch stop layer, and forming a second photosensitive layer pattern on the second etch stop layer;
• forming a second opening for an inter-connection groove by etching the second etch stop layer using the second photosensitive layer pattern as a mask;
• simultaneously forming the inter-connection groove and the via hole by etching the first insulation layer and the second insulation layer using the second etch stop layer and the first etch stop layer as a mask;
• and
• forming a metal line by filling the inter-connection groove and the via hole with conductive materials.

A method of forming a metal line in a semiconductor device, comprising:

• sequentially forming a first etch stop layer, a first insulation layer, and a second etch stop layer on a conductive layer;
• forming a first photosensitive layer pattern having a first opening on the second etch stop layer;
• etching the second etch stop layer by using the first photosensitive layer pattern as a mask to a degree that the first insulation layer is exposed, and then removing the first photosensitive layer pattern;
• sequentially forming a second insulation layer and a third etch stop layer on the first insulation layer and the second etch stop layer, and forming a second photosensitive layer pattern having a second opening on the third etch stop layer;
• etching the third etch stop layer by using the second photosensitive layer pattern as a mask to a degree that the second insulation layer is exposed, and removing the second photosensitive layer pattern;
• forming an inter-connection groove and a via hole by sequentially etching the first insulation layer using the third etch stop layer and the second etch stop layer as a mask;
• forming a spacer insulation layer on an entire surface of a substrate including the inter-connection groove and the via hole;
• forming a spacer at both sidewalls of the inter-connection groove and the via hole by performing an etch back process using the thickness of the spacer insulation layer as a target;
• forming a via hole by additionally etching the first insulation layer to a degree that the first etch stop layer is exposed;
• simultaneously forming the inter-connection groove and the via hole by removing the first etch stop layer, the second etch stop layer, the third etch stop layer, and the spacer insulation layer;
• and
• forming a metal line by performing a CMP process for polishing conductive materials which fill in the inter-connection groove and the via hole.