Patent ID: 6828251
Filing Date: 2004-12-07
Classification: C04B,H01L

Abstract:
A method for plasma etching with etching selectivity for a low-K carbon containing dielectric material layer and underlying etch stop layer comprising the steps of:providing a substrate comprising a low-K carbon containing dielectric material layer overlying a nitride containing etch stop underlayer; providing a photoresist layer overlying the low-K carbon containing dielectric material layer; defining a pattern comprising the photoresist layer such that a portion of the low-K carbon containing dielectric material layer is exposed for etching; and, carrying out a first plasma etching process by introducing a gas comprising fluorocarbons, nitrogen, and oxygen at a nitrogen to oxygen ratio of at least about 10 and a fluorine to carbon ratio within a range of about 2 to about 3 into the etch chamber to etch through a thickness portion of the low-K carbon containing dielectric material layer.