Conductive structures, wordlines and transistors

Patent metadata

Field	Value
Publication number	US-9972628-B1
Application number	US-201615349808-A
Country	US
Kind code	B1
Filing date	Nov 11, 2016
Priority date	Nov 11, 2016
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

Some embodiments include a conductive structure which has a first conductive material having a work function of at least 4.5 eV, and a second conductive material over and directly against the first conductive material. The second conductive material has a work function of less than 4.5 eV, and is shaped as an upwardly-opening container. The conductive structure includes a third conductive material within the upwardly-opening container shape of the second conductive material and directly against the second conductive material. The third conductive material is a different composition relative to the second conductive material. Some embodiments include wordlines, and some embodiments include transistors.

First claim

We claim:

1. A conductive structure, comprising:
a first conductive material having a work function of at least 4.5 eV;
a second conductive material over and directly against the first conductive material, and having a work function of less than 4.5 eV; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material;
the third conductive material being a different composition relative to the second conductive material; and
wherein the first conductive material comprises one or more of TiN, TaN and WN; where the formulas indicate primary constituents rather than specific stoichiometries.

2. A conductive structure, comprising:
a first conductive material having a work function of at least 4.5 eV;
a second conductive material over and directly against the first conductive material, and having a work function of less than 4.5 eV; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; and
wherein the second conductive material comprises one or more of WSiCN, TiSiN, WSiN, TiSiCN and TiAlN; where the formulas indicate primary constituents rather than specific stoichiometries.

3. The conductive structure of claim 2 wherein the third conductive material comprises one or more of Ir, Ru, Rh, Ti and W.

4. A conductive structure, comprising:
a first conductive material having a work function of at least 4.5 eV;
a second conductive material over and directly against the first conductive material, and having a work function of less than 4.5 eV; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; wherein the third conductive material comprises one or more of Ir, Ru, Rh, Ti and W; and
wherein the third conductive material further comprises one or more of Al, C, N and Si.

5. The conductive structure of claim 4 extending into a recess within a semiconductor material.

6. The conductive structure of claim 4 extending into a recess within a semiconductor material, and being spaced from the semiconductor material by dielectric material.

7. A conductive structure, comprising:
a first conductive material having a work function of at least 4.5 eV;
a second conductive material over and directly against the first conductive material, and having a work function of less than 4.5 eV; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; and
wherein the first conductive material is part of a conductive block which includes a fourth conductive material in combination with the first conductive material; the conductive block having an outer peripheral surface which includes an upper surface; the upper surface comprising regions of the first and fourth conductive materials, and the second conductive material being over and directly against the upper surface of the conductive block; all portions of the outer peripheral surface of the conductive block besides the upper surface only comprising the first conductive material.

8. The conductive structure of claim 7 wherein the third and fourth conductive materials are a same composition as one another.

9. A wordline, comprising:
a first conductive material comprising one or both of TaN and WN; where the formulas indicate primary constituents rather than specific stoichiometries;
a second conductive material over and directly against the first conductive material, and having a work function of less than a work function of the first conductive material; the second conductive material being shaped as an upwardly-opening container; and
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material.

10. A wordline, comprising:
a first conductive material comprising one or more of TiN, TaN and WN; where the formulas indicate primary constituents rather than specific stoichiometries;
a second conductive material over and directly against the first conductive material, and having a work function of less than a work function of the first conductive material; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; and
wherein the second conductive material comprises one or more of WSiCN, TiSiN, WSiN, TiSiCN and TiAlN; where the formulas indicate primary constituents rather than specific stoichiometries.

11. The wordline of claim 10 wherein the third conductive material comprises one or more of Ir, Ru, Rh, Ti and W.

12. A wordline, comprising:
a first conductive material comprising one or more of TiN, TaN and WN; where the formulas indicate primary constituents rather than specific stoichiometries;
a second conductive material over and directly against the first conductive material, and having a work function of less than a work function of the first conductive material; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; wherein the third conductive material comprises one or more of Ir, Ru, Rh, Ti and W; and
wherein the third conductive material further comprises one or more of Al, C, N and Si.

13. A wordline, comprising:
a first conductive material comprising one or more of TiN, TaN and WN; where the formulas indicate primary constituents rather than specific stoichiometries;
a second conductive material over and directly against the first conductive material, and having a work function of less than a work function of the first conductive material; the second conductive material being shaped as an upwardly-opening container;
a third conductive material within the upwardly-opening container shape of the second conductive material and being directly against the second conductive material; the third conductive material being a different composition relative to the second conductive material; and
wherein the first conductive material comprises TiN, the second conductive material comprises WSiCN and/or TiSiN, and the third conductive material consists of W and/or Ti; where the formulas indicate primary constituents rather than specific stoichiometries.

14. A transistor, comprising:
a gate r

Assignees

• Micron Technology Inc

Inventors

• Goswami Jaydeb
• Bian Zailong
• Hu Yushi
• Blomiley Eric R
• Guha Jaydip
• Gehrke Thomas

Classifications

• H10W20/4446

  Refractory-metal alloys · CPC title

• H10W20/435 Primary

  Cross-sectional shapes or dispositions of interconnections · CPC title

• H10W20/425

  Barrier, adhesion or liner layers · CPC title

• H01L29/4236

  Electricity · mapped topic

• H01L29/0847

  Electricity · mapped topic