Abstract: A method of forming a dual damascene line structure suitable for forming a fine pattern is disclosed in the present invention. The method for forming a dual damascene line structure on a substrate includes sequentially depositing an inter-metal dielectric and a first hard mask over the substrate, partially removing the first hard mask to have a positive trench pattern using a first photoresist pattern as a mask, forming a second hard mask having a substantially different etch selectivity from the first hard mask on the partially removed portion of the first hard mask, selectively removing the first hard mask to have a negative via hole pattern using a second photoresist pattern as a mask, partially removing the inter-metal dielectric to have a via hole pattern using the first hard mask as a mask, and forming a trench and a via hole by removing the exposed first hard mask and selectively etching the inter-metal dielectric using the second hard mask.

Abstract: A method of forming a dual damascene line structure suitable for forming a fine pattern is disclosed in the present invention. The method for forming a dual damascene line structure on a substrate includes sequentially depositing an inter-metal dielectric and a first hard mask over the substrate, partially removing the first hard mask to have a positive trench pattern using a first photoresist pattern as a mask, forming a second hard mask having a substantially different etch selectivity from the first hard mask on the partially removed portion of the first hard mask, selectively removing the first hard mask to have a negative via hole pattern using a second photoresist pattern as a mask, partially removing the inter-metal dielectric to have a via hole pattern using the first hard mask as a mask, and forming a trench and a via hole by removing the exposed first hard mask and selectively etching the inter-metal dielectric using the second hard mask.