Methods used in the fabrication of integrated circuitry

Patent metadata

Field	Value
Publication number	US-10971500-B2
Application number	US-201916433966-A
Country	US
Kind code	B2
Filing date	Jun 6, 2019
Priority date	Jun 6, 2019
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A method used in fabrication of integrated circuitry comprises forming metal material outwardly of a substrate. At least a majority (i.e., up to and including 100%) of the metal material contains ruthenium in at least one of elemental-form, metal compound-form, or alloy-form. A masking material is formed outwardly of the ruthenium-containing metal material. The masking material comprises at least one of nine specifically enumerated materials or category of materials. The masking material is used as a mask while etching through an exposed portion of the ruthenium-containing metal material to form a feature of integrated circuitry that comprises the ruthenium-containing metal material.

First claim

The invention claimed is:

1. A method used in fabrication of integrated circuitry, comprising:
forming a conductive material outwardly of a substrate, the conductive material having a first thickness and comprising a refractory metal nitride other than RuN;
forming metal material outwardly of and in direct physical contact with the conductive material; at least a majority of the metal material containing ruthenium in at least one of elemental-form, metal compound-form, or alloy-form;
forming a masking material outwardly of the ruthenium-containing metal material, the masking material having a second thickness at least twice the first thickness and comprising at least one of:
a refractory metal, other than ruthenium, that is in at least one of elemental-form or alloy-form;
a refractory metal nitride other than RuN;
a refractory metal oxide other than RuO 2 and RuO 4 ;
a refractory metal silicide other than Ru 2 Si, Ru 4 Si 3 , RuSi, and Ru 2 Si 3 ;
a refractory metal carbide other than RuC;
aluminum in at least one of elemental-form or alloy-form;
AlN x ;
AlO x ; or
AlC x ; and

in an absence of additional material over the masking material, using the masking material as a mask while etching an exposed portion of the ruthenium-containing metal material to form a feature of integrated circuitry that comprises the ruthenium-containing metal material, the etching using an etch chemistry comprising an inert gas in combination with at least one feed gas selected from O 2 and Cl 2 .

2. The method of claim 1 wherein the masking material comprises the refractory metal other than ruthenium that is in at least one of elemental-form or alloy-form.

3. The method of claim 1 wherein the masking material comprises the refractory metal nitride other than RuN.

4. The method of claim 1 wherein the masking material comprises the refractory metal oxide other than RuO 2 and RuO 4 .

5. The method of claim 1 wherein the masking material comprises the refractory metal silicide other than Ru 2 Si, Ru 4 Si 3 , RuSi, and Ru 2 Si 3 .

6. The method of claim 1 wherein the masking material comprises the refractory metal carbide other than RuC.

7. The method of claim 1 wherein the masking material comprises the aluminum in at least one of elemental-form or alloy-form.

8. The method of claim 1 wherein the masking material comprises the AlN x .

9. The method of claim 1 wherein the masking material comprises the AlO x .

10. The method of claim 1 wherein the masking material comprises the AlC x .

11. The method of claim 1 wherein the masking material comprises one of hafnium, titanium, tantalum, or tungsten.

12. The method of claim 1 wherein the masking material comprises TiN.

13. The method of claim 1 comprising removing all remaining of the masking material after the removing the exposed portion of the ruthenium-containing material.

14. The method of claim 1 wherein the masking material comprises the same refractory metal nitride as that of the conductive material.

15. The method of claim 14 wherein the refractory metal nitride comprises TiN.

16. The method of claim 1 wherein the masking material comprises a different refractory metal nitride than that of the conductive material.

17. The method of claim 1 wherein the masking material during the etching consists essentially of the at least one of:
the refractory metal other than ruthenium that is in at least one of elemental-form or alloy-form;
the refractory metal nitride other than RuN;
the refractory metal oxide other than RuO 2 and RuO 4 ;
the refractory metal silicide other than Ru 2 Si, Ru 4 Si 3 , RuSi, and Ru 2 Si 3 ;
the refractory metal carbide other than RuC;
aluminum in at least one of elemental-form or alloy-form;
AlN x ;
AlO x ; or
AlC x .

18. The method of claim 17 wherein the masking material has a minimum thickness of at least 100 Angstroms.

19. The method of claim 1 wherein the feature comprises a horizontally-elongated conductive line.

20. The method of claim 1 wherein the metal material consists essentially of ruthenium in at least one of elemental-form, metal compound-form, or alloy-form.

21. The method of claim 1 wherein the metal material consists of ruthenium in at least one of elemental-form, metal compound-form, or alloy-form.

22. A method used in fabrication of integrated circuitry, comprising:
forming metal material outwardly of a substrate; at least a majority of the metal material containing ruthenium in at least one of elemental-form, metal compound-form, or alloy-form;
forming a masking material outwardly of the ruthenium-containing metal material, the masking material comprising at least one of:
a refractory metal, other than ruthenium, that is in at least one of elemental-form or alloy-form;
a refractory metal nitride other than RuN;
a refractory metal oxide other than RuO 2 and RuO 4 ;
a refractory metal silicide other than Ru 2 Si, Ru 4 Si 3 , RuSi, and Ru 2 Si 3 ;
a refractory metal carbide other than RuC;
aluminum in at least one of elemental-form or alloy-form;
AlN x ;
AlO x ; or
AlC x ;

forming a carbon mask outwardly of the masking material; and
using the carbon mask and masking material as a mask while etching removing an exposed portion of the ruthenium-containing metal material to form a feature of integrated circuitry that comprises the ruthenium-containing metal material, the etching using an etch chemistry comprising an inert gas in combination with at least one feed gas selected from O 2 and Cl 2 .

23. A method of forming a conductive line structure of integrated circuitry, comprising:
forming a vertical stack comprising a first refractory metal nitride other than RuN, a metal material vertically outward of first the refractory metal nitride, and an insulator material vertically outward of the metal material; at least a majority of the metal material containing ruthenium in at least one of elemental-form, metal compound-form, or alloy-form;
forming a masking material vertically outward of and directly against the insulator material, the masking material comprising at least one of:
a refractory metal, other than ruthenium, that is in at least one of elemental-form or alloy-form, the refractory metal being selected from the group consisting of chromium, manganese, zirconium, molybdenum, technetium, ruthenium, rhodium, hafnium, tungsten, rhenium, osmium, or iridium;
a second refractory metal nitride other than RuN, the refractory metal nitride comprising a refractory metal selected from group consisting of vanadium, chromium, manganese, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, hafnium, tungsten, rhenium, osmium, or iridium;
a refractory metal oxide other than RuO 2 and RuO 4 ;
a refractory metal silicide other than Ru 2 Si, Ru 4 Si 3 , RuSi, and Ru 2 Si 3 ;
a refractory metal carbide other than RuC;
aluminum in at least one of elemental-form or alloy-form;
AlN x ;
AlO x ; or
AlC x ; and

using the masking material as a mask while etching an exposed portion of the insulator material, the ruthenium-containing metal material, and the first refractory metal nitride to form a conductive line structure comprising the insulator material, the ruthenium-containing metal material, and the first refractory metal nitride, the etching using an etch chemistry comprising an inert gas in combination with at least one feed gas selected from O 2 and Cl 2 .

Assignees

• Micron Technology Inc

Inventors

• Rui Ying
• Liu Tong
• Lee Yi Fang
• Colombo Davide
• Borsari Silvia
• Johnson Austin

Classifications

• H10W20/0633

  using subtractive patterning of the conductive members · CPC title

• H10W20/031

  of conductive parts of the interconnections · CPC title

• H10W20/425

  Barrier, adhesion or liner layers · CPC title

• H10W20/063

  by forming conductive members before forming protective insulating material · CPC title

• H10P50/71

  using masks for conductive or resistive materials · CPC title