Patent ID: 6579791
Filing Date: 2003-06-17
Classification: H01L

Abstract:
A method of fabricating a dual damascene opening, comprising the sequential steps of:providing a structure having a first low-k material layer formed thereover; forming a first stop layer over the first low-k material layer; forming a second low-k material layer over the first stop layer; forming a second stop layer over the second low-k material layer; etching: the second stop layer; the second low-k material layer; the first stop layer; and the first low-k material layer to form a via opening exposing a portion of the structure; forming a photoresist layer over the second stop layer and filling the via opening; the photoresist layer having a treated upper portion including a central trench pattern area that is wider than, and substantially centered over, the via opening; the treated upper portion of the photoresist layer preventing any effects to the underlying photoresist layer so that the underlying photoresist layer does not deleteriously interact with the first or second low-k material layer; removing: the central trench pattern area of the upper treated portion of the photoresist and the photoresist under the central trench pattern area to form a trench pattern opening exposing a portion of the second stop layer under the removed central trench pattern area; and the photoresist layer within the via opening while leaving a portion of the photoresist layer within the via opening overlying the portion of the structure that was exposed by the via opening; and transferring the trench pattern opening to the second stop layer and the second low-k material layer to form a trench substantially centered over the remaining via opening and completing the dual damascene opening.