Self aligned buried power rail

Patent metadata

Field	Value
Publication number	US-2020006112-A1
Application number	US-201916568902-A
Country	US
Kind code	A1
Filing date	Sep 12, 2019
Priority date	Apr 7, 2017
Publication date	Jan 2, 2020
Grant date	—

Abstract

The present disclosure relates to semiconductor structures and, more particularly, to self-aligned buried power rail structures and methods of manufacture. The method includes: forming at least one fin structure of a first dimension in a substrate; forming at least one fin structure of a second dimension in the substrate; removing at least a portion of the at least one fin structure of the second dimension to form a trench; filling the trench with conductive metal to form a buried power rail structure within the trench; and forming a contact to the buried power rail structure.

First claim

What is claimed:

1 . A structure comprising:
a partial fin structure of substrate material; a buried power rail comprising conductive metal fill material aligned with and over the partial fin structure; and a contact to the buried power rail.

2 . The structure of claim 1 , wherein a space between the buried power rail and neighboring fin structures is substantially equal to fin to fin spacing.

3 . The structure of claim 1 , wherein the buried power rail is a metal fill material over a liner of conductive barrier material.

4 . The structure of claim 3 , wherein the liner of conductive barrier material is a multi-layer liner.

5 . The structure of claim 4 , wherein the multi-layer liner comprises a first dielectric film to isolate electrically the substrate material and a single or bi-layer of barrier material.

6 . The structure of claim 5 , wherein the single or bi-layer of barrier material is one of TaN, TiN, Co or Ru.

7 . The structure of claim 5 , wherein the metal fill material is a high melting temperature metal.

8 . The structure of claim 1 , wherein the buried power rail is partially recessed within the partial fin structure of substrate material.

9 . The structure of claim 3 , further comprising a capping material on exposed surfaces of the metal fill material and the liner.

10 . The structure of claim 9 , further comprising a gap fill material on the capping material.

11 . The structure of claim 10 , wherein the gap fill material is recessed and the contact is within the recessed gap fill material contacting to the buried power rail.

Assignees

• Globalfoundries Inc

Inventors

• Licausi Nicholas V
• Bouche Guillaume
• Liebmann Lars W

Classifications

• H10W20/427

  Power or ground buses · CPC title

• H10W20/20

  Interconnections within wafers or substrates, e.g. through-silicon vias [TSV] · CPC title

• H10W20/021 Primary

  of interconnections within wafers or substrates · CPC title

• H01L27/10879

  Electricity · mapped topic

• H01L27/0886

  Electricity · mapped topic