Interconnects separated by a dielectric region formed using removable sacrificial plugs

Patent metadata

Field	Value
Publication number	US-10896874-B2
Application number	US-201916363585-A
Country	US
Kind code	B2
Filing date	Mar 25, 2019
Priority date	Mar 25, 2019
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

Structures that include interconnects and methods of forming structures that include interconnects. A first interconnect is formed in a first trench in an interlayer dielectric layer, and a second interconnect in a second trench in the interlayer dielectric layer. The second interconnect is aligned along a longitudinal axis with the first interconnect. A dielectric region is arranged laterally arranged between the first interconnect and the second interconnect. The interlayer dielectric layer is composed of a first dielectric material, and the dielectric region is composed of a second dielectric material having a different composition than the first dielectric material.

First claim

What is claimed is:

1. A structure comprising:
an interlayer dielectric layer;
a first interconnect feature in a first interconnect opening in the interlayer dielectric layer;
a second interconnect feature in a second interconnect opening in the interlayer dielectric layer, the second interconnect feature aligned along a longitudinal axis with the first interconnect feature; and
a dielectric region laterally arranged between a portion of the first interconnect feature and a portion of the second interconnect feature,
wherein the portion of the first interconnect feature and the portion of the second interconnect feature are separated along the longitudinal axis by a spacing equal to a dimension of the dielectric region, the first interconnect feature and the second interconnect feature have a first width in a direction transverse to the longitudinal axis, and the dielectric region has a second width that is substantially equal to the first width, the interlayer dielectric layer is comprised of a first dielectric material, and the dielectric region is comprised of a second dielectric material having a different composition than the first dielectric material.

2. The structure of claim 1 wherein the first interconnect opening includes a first trench, the first interconnect feature includes a first interconnect in the first trench, the second interconnect opening includes a second trench, and the second interconnect feature includes a second interconnect in the second trench.

3. The structure of claim 2 wherein the first interconnect opening further includes a first via opening and the second interconnect opening further includes a second via opening, the first interconnect feature includes a first via in the first via opening, and the second interconnect feature includes a second via in the second via opening.

4. The structure of claim 3 wherein the dielectric region is arranged over a portion of the interlayer dielectric layer, and the portion of the interlayer dielectric layer is arranged laterally between the first via and the second via.

5. The structure of claim 4 wherein the first via has a side surface in direct contact with the portion of the interlayer dielectric layer, and the second via has a side surface in direct contact with the portion of the interlayer dielectric layer.

6. The structure of claim 3 further comprising:
a metallization level including a third interconnect and a fourth interconnect; and
a cap layer between the metallization level and the interlayer dielectric layer,
wherein the first via and the first via opening penetrate through the cap layer to the third interconnect, and the second via and the second via opening penetrate through the cap layer to the fourth interconnect.

7. The structure of claim 2 wherein the portion of the first interconnect feature is the first interconnect, and the portion of the second interconnect feature is the second interconnect.

8. The structure of claim 1 wherein the first dielectric material has a dielectric constant of less than or equal to 2.5, and the second dielectric material has a dielectric constant of greater than or equal to 3.9.

9. The structure of claim 1 wherein the first dielectric material has a dielectric constant of less than or equal to 2.5, and the second dielectric material is silicon nitride.

10. The structure of claim 1 wherein the dielectric region is arranged directly between the portion of the first interconnect feature and the portion of the second interconnect feature.

11. The structure of claim 1 wherein the portion of the first interconnect feature is in direct contact with the dielectric region, and the portion of the second interconnect feature is in direct contact with the dielectric region.

12. The structure of claim 1 wherein the first interconnect feature includes a first interconnect and a first via in the first interconnect opening, the second interconnect feature includes a second interconnect and a second via in the second interconnect opening, the first interconnect and the first via are in direct contact with the dielectric region, and the second interconnect and the second via are in direct contact with the dielectric region.

13. The structure of claim 12 wherein the dielectric region has a length, the first interconnect and the second interconnect are separated by a first spacing equal to the length, and the first via and the second via are separated by a second spacing equal to the length.

Assignees

• Globalfoundries Inc

Inventors

• Ning Guoxiang
• Xie Ruilong
• Sun Lei

Classifications

• H10W20/435

  Cross-sectional shapes or dispositions of interconnections · CPC title

• H10W20/085 Primary

  involving intermediate temporary filling with material · CPC title

• H10W20/056

  by filling conductive material into holes, grooves or trenches · CPC title

• H10W20/47

  comprising two or more dielectric layers having different properties, e.g. different dielectric constants · CPC title

• H10W20/071

  of dielectric parts thereof · CPC title