US 2002/0173157 A1 · Dual damascene method employing composite low dielectric constant dielectric layer having intrinsic etch stop characteristics

Abstract

Within a dual damascene method for forming a contiguous patterned conductor interconnect and patterned conductor stud layer within a corresponding trench contiguous with a corresponding via formed through a dielectric layer formed of a comparatively low dielectric constant dielectric material, the dielectric layer is, prior to dual damascene etching, formed of a patterned first dielectric layer having formed thereupon a blanket second dielectric layer. The patterned first dielectric layer is formed of a first dielectric material and the blanket second dielectric layer is formed of a second dielectric material, where each of the first dielectric material and the second dielectric material has a dielectric constant of less than about 4.0, but wherein the first dielectric material serves as an intrinsic etch stop when dual damascene etching the dielectric layer.

Claims15

Dependent claims

A method for forming an aperture through a dielectric layer comprising:

providing a substrate;
forming upon the substrate a patterned first dielectric layer formed of a first dielectric material having a first dielectric constant of less than about 4.0, the patterned first dielectric layer defining a via;
forming upon the patterned first dielectric layer and filling the via a blanket second dielectric layer formed of a second dielectric material having a second dielectric constant of less than about 4.0;
forming over the blanket second dielectric layer a patterned mask layer which defines the location of a trench to be formed through the blanket second dielectric layer, where an areal dimension of the trench is greater than and at least in part overlapping an areal dimension of the via;
and
etching, while employing the patterned mask layer in conjunction with an anisotropic etch method, the blanket second dielectric layer to form an aperture comprising:
the trench;
and
at least a portion of the via, where the patterned first dielectric layer provides an intrinsic etch stop within the anisotropic etch method.

6 more elements

A method for forming a patterned conductor layer within an aperture through a dielectric layer comprising:

providing a substrate;
forming upon the substrate a patterned first dielectric layer formed of a first dielectric material having a first dielectric constant of less than about 4.0, the patterned first dielectric layer defining a via;
forming upon the patterned first dielectric layer and filling the via a blanket second dielectric layer formed of a second dielectric material having a second dielectric constant of less than about 4.0;
forming over the blanket second dielectric layer a patterned mask layer which defines the location of a trench to be formed through the blanket second dielectric layer, where an areal dimension of the trench is greater than and at least in part overlapping an areal dimension of the via;
etching, while employing the patterned mask layer in conjunction with an anisotropic etch method, the blanket second dielectric layer to form an aperture comprising:
the trench;
and
at least a portion of the via, where the patterned first dielectric layer provides an intrinsic etch stop within the anisotropic etch method;
and
forming within the aperture a contiguous patterned conductor interconnect and patterned conductor stud layer.

7 more elements

Dependencies are inferred from the claim text.

Dual damascene method employing composite low dielectric constant dielectric layer having intrinsic etch stop characteristics

Life of this patent

Dual damascene method employing composite low dielectric constant dielectric layer having intrinsic etch stop characteristics

Life of this patent

Abstract

Claims15