Capacitors having dielectric regions that include multiple metal oxide-comprising materials

• US 8,861,179 B2
• Filed: 08/29/2012
• Issued: 10/14/2014
• Est. Priority Date: 06/12/2009
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Krishnan, Rishikesh, Smythe, John, Bhat, Vishwanath, Rocklein, Noel, Srinivasan, Bhaskar, Hull, Jeff, Carlson, Chris
• Primary Examiner(s): Sinclair, David M
• Application Number:
  US13/597,708
• Publication Number:
  US 20120320494A1
• Time in Patent Office: 776 Days
• Field of Search: 361/312, 361/313, 361/320, 361/322
• US Class Current: 361/313
• CPC Class Codes: H01G 4/10 Metal-oxide dielectrics H01G4/085 takes precedence
• CPC Class Codes: H01L 28/56 the dielectric comprising two or more layers, e.g. comprising buffer layers, seed layers, gradient layers
• CPC Class Codes: H10B 12/00 Dynamic random access memory [DRAM] devices

Abstract

Capacitors and methods of forming capacitors are disclosed, and which include an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode. A capacitor dielectric region is received between the inner and the outer conductive metal capacitor electrodes and has a thickness no greater than 150 Angstroms. Various combinations of materials of thicknesses and relationships relative one another are disclosed which enables and results in the dielectric region having a dielectric constant k of at least 35 yet leakage current no greater than 1×10⁻⁷ amps/cm² at from −1.1V to +1.1V.

Claims

1. A capacitor comprising:

an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode; and

a capacitor dielectric region received between the inner and the outer conductive metal capacitor electrodes and having a thickness no greater than 150 Angstroms, the capacitor dielectric region comprising;

an optional first Al₂O₃-comprising material outward of the inner electrode, the optional first Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

a first material outward of the inner electrode and outward of the optional first Al₂O₃-comprising material if the optional first Al₂O₃-comprising material is present, the first material comprising at least one of ZrO₂ or HfO₂, the first material having a thickness of from 20 Angstroms to 50 Angstroms;

an optional second Al₂O₃-comprising material outward of the first material comprising at least one of ZrO₂ or HfO₂, the optional second Al₂O₃-comprising material having a thickness of from 0 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the first material that comprises the at least one of ZrO₂ or HfO₂ and outward of the optional second Al₂O₃-comprising material if the optional second Al₂O₃-comprising material is present, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second material outward of the TiO₂-comprising material, the second material comprising at least one of ZrO₂ or HfO₂, the second material having a thickness of from 10 Angstroms to 40 Angstroms, a sum of the thicknesses of the first material and the second material totaling no more than 70 Angstroms;

an optional third Al₂O₃-comprising material outward of the second material comprising at least one of ZrO₂ or HfO₂, the optional third Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

the capacitor dielectric region having in combination a dielectric constant k of at least 35 and leakage current no greater than 1×

10<sup>−

7</sup> amps/cm² at from −

1.1V to +1.1V; and

the capacitor dielectric region comprising the optional third Al₂O₃-comprising material, the capacitor dielectric region being void of each of the optional first and second Al₂O₃-comprising materials.

2. The capacitor of claim 1 wherein the first material comprises ZrO₂.

3. The capacitor of claim 1 wherein the first material comprises HfO₂.

4. The capacitor of claim 1 wherein the second material comprises ZrO₂.

5. The capacitor of claim 1 wherein the second material comprises HfO₂.

6. The capacitor of claim 1 wherein the capacitor dielectric region has a dielectric constant k of at least 40.

7. The capacitor of claim 1 wherein the capacitor dielectric region has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

8. The capacitor of claim 1 wherein the capacitor dielectric region has a dielectric constant k of at least 40 and has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

9. The capacitor of claim 1 wherein the first material comprises ZrO₂ and HfO₂.

10. The capacitor of claim 1 wherein the second material comprises ZrO₂ and HfO₂.

11. The capacitor of claim 1 wherein the first material comprises ZrO₂ and HfO₂ and the second material comprises ZrO₂ and HfO₂.

12. The capacitor of claim 1 wherein the first material is in direct physical touching contact with the inner electrode.

13. The capacitor of claim 1 wherein the third Al₂O₃-comprising material is in direct physical touching contact with the outer electrode.

14. A capacitor comprising:

an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode; and

a capacitor dielectric region received between the inner and the outer conductive metal capacitor electrodes and having a thickness no greater than 150 Angstroms, the capacitor dielectric region comprising;

an optional first Al₂O₃-comprising material outward of the inner electrode, the optional first Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

a first material outward of the inner electrode and outward of the optional first Al₂O₃-comprising material if the optional first Al₂O₃-comprising material is present, the first material comprising at least one of ZrO₂ or HfO₂, the first material having a thickness of from 20 Angstroms to 50 Angstroms;

an optional second Al₂O₃-comprising material outward of the first material comprising at least one of ZrO₂ or HfO₂, the optional second Al₂O₃-comprising material having a thickness of from 0 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the first material that comprises the at least one of ZrO₂ or HfO₂ and outward of the optional second Al₂O₃-comprising material if the optional second Al₂O₃-comprising material is present, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second material outward of the TiO₂-comprising material, the second material comprising at least one of ZrO₂ or HfO₂, the second material having a thickness of from 10 Angstroms to 40 Angstroms, a sum of the thicknesses of the first material and the second material totaling no more than 70 Angstroms;

an optional third Al₂O₃-comprising material outward of the second material comprising at least one of ZrO₂ or HfO₂, the optional third Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

the capacitor dielectric region having in combination a dielectric constant k of at least 35 and leakage current no greater than 1×

10<sup>−

7</sup> amps/cm² at from −

1.1V to +1.1V; and

the capacitor dielectric region comprising the optional third Al₂O₃-comprising material, the capacitor dielectric region being void of the optional first Al₂O₃-comprising material and comprising the optional second Al₂O₃-comprising material.

15. The capacitor of claim 14 wherein the capacitor dielectric region has a dielectric constant k of at least 40.

16. The capacitor of claim 14 wherein the capacitor dielectric region has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

17. The capacitor of claim 14 wherein the capacitor dielectric region has a dielectric constant k of at least 40 and has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

18. A capacitor comprising:

an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode; and

a capacitor dielectric region received between the inner and the outer conductive metal capacitor electrodes and having a thickness no greater than 150 Angstroms, the capacitor dielectric region comprising;

an optional first Al₂O₃-comprising material outward of the inner electrode, the optional first Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

a first material outward of the inner electrode and outward of the optional first Al₂O₃-comprising material if the optional first Al₂O₃-comprising material is present, the first material comprising at least one of ZrO₂ or HfO₂, the first material having a thickness of from 20 Angstroms to 50 Angstroms;

an optional second Al₂O₃-comprising material outward of the first material comprising at least one of ZrO₂ or HfO₂, the optional second Al₂O₃-comprising material having a thickness of from 0 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the first material that comprises the at least one of ZrO₂ or HfO₂ and outward of the optional second Al₂O₃-comprising material if the optional second Al₂O₃-comprising material is present, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second material outward of the TiO₂-comprising material, the second material comprising at least one of ZrO₂ or HfO₂, the second material having a thickness of from 10 Angstroms to 40 Angstroms, a sum of the thicknesses of the first material and the second material totaling no more than 70 Angstroms;

an optional third Al₂O₃-comprising material outward of the second material comprising at least one of ZrO₂ or HfO₂, the optional third Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

the capacitor dielectric region having in combination a dielectric constant k of at least 35 and leakage current no greater than 1×

10<sup>−

7</sup> amps/cm² at from −

1.1V to +1.1V; and

the capacitor dielectric region being void of the optional third Al₂O₃-comprising material, the capacitor dielectric region comprising each of the optional first and second Al₂O₃-comprising materials.

19. The capacitor of claim 18 wherein the capacitor dielectric region has a dielectric constant k of at least 40.

20. The capacitor of claim 18 wherein the capacitor dielectric region has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

21. The capacitor of claim 18 wherein the capacitor dielectric region has a dielectric constant k of at least 40 and has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

22. A capacitor comprising:

an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode; and

a capacitor dielectric region received between the inner and the outer conductive metal capacitor electrodes and having a thickness no greater than 150 Angstroms, the capacitor dielectric region comprising;

an optional first Al₂O₃-comprising material outward of the inner electrode, the optional first Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

a first material outward of the inner electrode and outward of the optional first Al₂O₃-comprising material if the optional first Al₂O₃-comprising material is present, the first material comprising at least one of ZrO₂ or HfO₂, the first material having a thickness of from 20 Angstroms to 50 Angstroms;

an optional second Al₂O₃-comprising material outward of the first material comprising at least one of ZrO₂ or HfO₂, the optional second Al₂O₃-comprising material having a thickness of from 0 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the first material that comprises the at least one of ZrO₂ or HfO₂ and outward of the optional second Al₂O₃-comprising material if the optional second Al₂O₃-comprising material is present, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second material outward of the TiO₂-comprising material, the second material comprising at least one of ZrO₂ or HfO₂, the second material having a thickness of from 10 Angstroms to 40 Angstroms, a sum of the thicknesses of the first material and the second material totaling no more than 70 Angstroms;

an optional third Al₂O₃-comprising material outward of the second material comprising at least one of ZrO₂ or HfO₂, the optional third Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

the capacitor dielectric region having in combination a dielectric constant k of at least 35 and leakage current no greater than 1×

10<sup>−

7</sup> amps/cm² at from −

1.1V to +1.1V; and

the capacitor dielectric region being void of the optional third Al₂O₃-comprising material, the capacitor dielectric region comprising the optional first Al₂O₃-comprising material and being void of the optional second Al₂O₃-comprising material.

23. The capacitor of claim 22 wherein the capacitor dielectric region has a dielectric constant k of at least 40.

24. The capacitor of claim 22 wherein the capacitor dielectric region has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

25. The capacitor of claim 22 wherein the capacitor dielectric region has a dielectric constant k of at least 40 and has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

26. A capacitor comprising:

an inner conductive metal capacitor electrode and an outer conductive metal capacitor electrode; and

a capacitor dielectric region received between the inner and the outer conductive metal capacitor electrodes and having a thickness no greater than 150 Angstroms, the capacitor dielectric region comprising;

an optional first Al₂O₃-comprising material outward of the inner electrode, the optional first Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

a first material outward of the inner electrode and outward of the optional first Al₂O₃-comprising material if the optional first Al₂O₃-comprising material is present, the first material comprising at least one of ZrO₂ or HfO₂, the first material having a thickness of from 20 Angstroms to 50 Angstroms;

an optional second Al₂O₃-comprising material outward of the first material comprising at least one of ZrO₂ or HfO₂, the optional second Al₂O₃-comprising material having a thickness of from 0 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the first material that comprises the at least one of ZrO₂ or HfO₂ and outward of the optional second Al₂O₃-comprising material if the optional second Al₂O₃-comprising material is present, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second material outward of the TiO₂-comprising material, the second material comprising at least one of ZrO₂ or HfO₂, the second material having a thickness of from 10 Angstroms to 40 Angstroms, a sum of the thicknesses of the first material and the second material totaling no more than 70 Angstroms;

an optional third Al₂O₃-comprising material outward of the second material comprising at least one of ZrO₂ or HfO₂, the optional third Al₂O₃-comprising material having a thickness of from 0 Angstroms to 10 Angstroms;

the capacitor dielectric region having in combination a dielectric constant k of at least 35 and leakage current no greater than 1×

10<sup>−

7</sup> amps/cm² at from −

1.1V to +1.1V; and

the capacitor dielectric region being void of the optional first Al₂O₃-comprising material, the capacitor dielectric region being void of the optional third Al₂O₃-comprising material, the capacitor dielectric region comprising the optional second Al₂O₃-comprising material, the at least one of ZrO₂ or HfO₂ of the second material being in direct physical touching contact with the outer electrode.

27. The capacitor of claim 26 wherein the capacitor dielectric region has a dielectric constant k of at least 40.

28. The capacitor of claim 26 wherein the capacitor dielectric region has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

29. The capacitor of claim 26 wherein the capacitor dielectric region has a dielectric constant k of at least 40 and has leakage current no greater than 5×

10<sup>−

8</sup> amps/cm² at from −

1.1V to +1.1V.

30. The capacitor of claim 26 wherein the at least one of ZrO₂ or HfO₂ of the first material is in direct physical touching contact with the inner electrode.

31. The capacitor of claim 26 wherein the capacitor dielectric region has a thickness no greater than 100 Angstroms.

32. The capacitor of claim 31 wherein the capacitor dielectric region has a thickness no greater than 75 Angstroms.

33. The capacitor of claim 26 wherein the second Al₂O₃-comprising material is in direct physical touching contact with the TiO₂-comprising material.