US 2021/0280465 A1 · Structurally Stable Self-Aligned Subtractive Vias

Abstract

Techniques for forming self-aligned subtractive top vias using a via hardmask supported by scaffolding are provided. In one aspect, a method of forming top vias includes: forming metal lines on a substrate using line hardmasks; patterning vias in the line hardmasks; filling the vias and trenches in between the metal lines with a via hardmask material to form via hardmasks and a scaffolding adjacent to and supporting the via hardmasks; removing the line hardmasks; and recessing the metal lines using the via hardmasks to form the top vias that are self-aligned with the metal lines. The scaffolding can also be placed prior to patterning of the vias in the line hardmasks. A structure formed in accordance with the present techniques containing top vias is also provided.

Claims20

Dependent claims

A method of forming top vias, the method comprising the steps of:

forming metal lines on a substrate using line hardmasks;
patterning vias in the line hardmasks;
filling the vias and trenches in between the metal lines with a via hardmask material, wherein the via hardmask material filling the vias comprises via hardmasks, and wherein the via hardmask material filling the trenches in between the metal lines comprises a scaffolding adjacent to and supporting the via hardmasks;
removing the line hardmasks;
and
recessing the metal lines using the via hardmasks to form the top vias that are self-aligned with the metal lines.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/813,682Filed 9 Mar 2020

Published

9 Sep 2021

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

H10W 20/069
Of conductive parts of the interconnections: by forming self-aligned vias or self-aligned contact plugs
H10P 50/71
Etching of wafers, substrates or parts of devices: using masks for conductive or resistive materials
H10W 20/063
Of conductive parts of the interconnections: by forming conductive members before forming protective insulating material
H10W 20/0633
By forming conductive members before forming protective insulating material: using subtractive patterning of the conductive members

Structurally Stable Self-Aligned Subtractive Vias

Life of this patent

Structurally Stable Self-Aligned Subtractive Vias

Life of this patent

Abstract

Claims20