Process for forming a dual damascene structure

摘要

The invention describes a method for forming a dual damascene structure. An etch stop layer (150) is formed on a dielectric layer (140). A second dielectric layer (160) is formed on the etch stop layer (150) and an ARC layer (170) is formed the second dielectric layer. A first trench (185) and a second trench (195) are then simultaneously formed in the first and second dielectric layers (140) and (160) respectively.