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

• US 8,310,807 B2
• Filed: 06/12/2009
• Issued: 11/13/2012
• Est. Priority Date: 06/12/2009
• Status: Expired due to Fees

• 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:
  US12/483,474
• Publication Number:
  US 20100315760A1
• Time in Patent Office: 1,250 Days
• Field of Search: 361/311, 361/312, 361/313, 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;

a first Al₂O₃-comprising material outward of the inner electrode, the first Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

a ZrO₂-comprising material outward of the first Al₂O₃-comprising material, the ZrO₂-comprising material having a thickness of from 30 Angstroms to 70 Angstroms;

a second Al₂O₃-comprising material outward of the ZrO₂-comprising material, the second Al₂O₃-comprising material having a thickness of from 2 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the second Al₂O₃-comprising material, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms; and

a sum of the thicknesses of the first Al₂O₃-comprising material, the ZrO₂-comprising material, and the second Al₂O₃-comprising material totals no more than 70 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.

2. The capacitor of claim 1 wherein the capacitor dielectric region has a thickness no greater than 100 Angstroms.

3. The capacitor of claim 2 wherein the capacitor dielectric region has a thickness no greater than 75 Angstroms.

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

5. 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.

6. The capacitor of claim 1 wherein the first Al₂O₃-comprising material is in direct physical touching contact with the inner electrode.

7. The capacitor of claim 1 wherein the ZrO₂-comprising material is in direct physical touching contact with the first Al₂O₃-comprising material.

8. The capacitor of claim 1 wherein the ZrO₂-comprising material is not in direct physical touching contact with the first Al₂O₃-comprising material.

9. The capacitor of claim 8 comprising an Al_xZr_yO_z-comprising material received between the first Al₂O₃-comprising material and the ZrO₂-comprising material, the first Al₂O₃-comprising material and the ZrO₂-comprising material being in direct physical touching contact with the Al_xZr_yO_z-comprising material.

10. The capacitor of claim 1 wherein the second Al₂O₃-comprising material is in direct physical touching contact with the ZrO₂-comprising material.

11. The capacitor of claim 1 wherein the second Al₂O₃-comprising material is not in direct physical touching contact with the ZrO₂-comprising material.

12. The capacitor of claim 11 comprising an Al_xZr_yO_z-comprising material received between the ZrO₂-comprising material and the second Al₂O₃-comprising material, the ZrO₂-comprising material and the second Al₂O₃-comprising material being in direct physical touching contact with the Al_xZr_yO_z-comprising material.

13. The capacitor of claim 1 wherein the TiO₂-comprising material is in direct physical touching contact with the outer electrode.

14. The capacitor of claim 1 wherein the TiO₂-comprising material is in direct physical touching contact with the second Al₂O₃-comprising material.

15. The capacitor of claim 1 wherein the TiO₂-comprising material is not in direct physical touching contact with the second Al₂O₃-comprising material.

16. The capacitor of claim 15 comprising a Ti_xAl_yO_z-comprising material received between the second Al₂O₃-comprising material and the TiO₂-comprising material, the second Al₂O₃-comprising material and the TiO₂-comprising material being in direct physical touching contact with the Ti_xAl_yO_z-comprising material.

17. The capacitor of claim 1 wherein the second Al₂O₃-comprising material is of different composition from that of the first Al₂O₃-comprising material.

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;

a first Al₂O₃-comprising material outward of the inner electrode, the first Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

a TiO₂-comprising material outward of the first Al₂O₃-comprising material, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second Al₂O₃-comprising material outward of the TiO₂-comprising material, the second Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

an Al_xZr_yO_z-comprising material received between at least one of a) the first Al₂O₃-comprising material and the TiO₂-comprising material, and b) the second Al₂O₃-comprising material and the TiO₂-comprising material; and

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.

19. The capacitor of claim 18 wherein the Al_xZr_yO_z-comprising material is received between the first Al₂O₃-comprising material and the TiO₂-comprising material.

20. The capacitor of claim 18 wherein the Al_xZr_yO_z-comprising material is received between the second Al₂O₃-comprising material and the TiO₂-comprising material.

21. The capacitor of claim 18 wherein Al_xZr_yO_z-comprising material is received between the first Al₂O₃-comprising material and the TiO₂-comprising material, and Al_xZr_yO_z-comprising material is received between the second Al₂O₃-comprising material and the TiO₂-comprising material.

22. The capacitor of claim 18 wherein the second Al₂O₃-comprising material has a thickness of from 4 Angstroms to 7 Angstroms.

23. The capacitor of claim 18 wherein the capacitor dielectric region has a thickness no greater than 100 Angstroms.

24. The capacitor of claim 23 wherein the capacitor dielectric region has a thickness no greater than 75 Angstroms.

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

26. 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.

27. The capacitor of claim 18 wherein the second Al₂O₃-comprising material is of different composition from that of the first Al₂O₃-comprising material.

28. 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;

a first Al₂O₃-comprising material outward of the inner electrode, the first Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

a TiO₂-comprising material outward of the first Al₇O₃-comprising material, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second Al₂O₃-comprising material outward of the TiO₂-comprising material, the second Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

a ZrO₂-comprising material outward of the second Al₂O₃-comprising material, the ZrO₂-comprising material having a thickness of from 30 Angstroms to 70 Angstroms;

a third Al₂O₃-comprising material outward of the ZrO₂-comprising material, the third Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms; and

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.

29. 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 ZrO₂-comprising 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 ZrO₂-comprising material having a thickness of from 30 Angstroms to 70 Angstroms;

a second Al₂O₃-comprising material outward of the ZrO₂-comprising material, the second Al₂O₃-comprising material having a thickness of from 2 Angstroms to 16 Angstroms;

a TiO₂-comprising material outward of the second Al₂O₃-comprising material, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a third Al₂O₃-comprising material outward of the TiO₂-comprising material, the third Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms; and

a sum of the thicknesses of the optional first Al₂O₃-comprising material if present, the ZrO₂-comprising material, and the second Al₂O₃-comprising material totals no more than 70 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.

30. The capacitor of claim 29 wherein the capacitor dielectric region comprises the optional first Al₂O₃-comprising material outward of the inner electrode and inward of the ZrO₂-comprising material.

31. The capacitor of claim 29 wherein the capacitor dielectric region is void of the optional first Al₂O₃-comprising material outward of the inner electrode and inward of the ZrO₂-comprising material.

32. 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 33 Angstroms, the capacitor dielectric region comprising;

a first Al₂O₃-comprising material outward of the inner electrode, the first Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms;

a TiO₂-comprising material outward of the first Al₂O₃-comprising material, the TiO₂-comprising material having a thickness of from 40 Angstroms to 80 Angstroms;

a second Al₂O₃-comprising material outward of the TiO₂-comprising material, the second Al₂O₃-comprising material having a thickness of from 2 Angstroms to 10 Angstroms, the second Al₂O₃ comprising material being of different composition from that of the first Al₂O₃-comprising material; and

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.