Patent ID: 7196002
Filing Date: 2007-03-27
Classification: H01L

Abstract:
1. A method of forming a dual damascene structure, comprising: providing a substrate with an etch stop layer formed thereabove; forming a dielectric layer above the etch stop layer; forming an anti-reflective coating layer above the dielectric layer; forming a first patterned photoresist layer above the anti-reflective coating layer, the first patterned photoresist layer having a via hole pattern; etching through the via hole pattern in the anti-reflective coating layer, the dielectric layer, and the etch stop layer to form a via hole, wherein the etch stop layer in the via hole is completely removed in the same etching step; filling the via hole with a sacrificial via fill layer; forming a second patterned photoresist layer above the sacrificial via fill layer, the second patterned photoresist layer having a trench pattern; etching the trench pattern into the sacrificial via fill layer, the anti-reflective coating layer, and the dielectric layer to form a trench, wherein the trench is not substantially adjacent to the etch stop layer; removing the sacrificial via fill layer in the via hole; and forming a conductive layer in the via hole and trench.