Electroless deposition of doped noble metals and noble metal alloys

• US 20020098711A1
• Filed: 02/27/2002
• Published: 07/25/2002
• Est. Priority Date: 08/31/2000
• Status: Active Grant

• Current Assignee: Rita J. Klein
• Original Assignee: Rita J. Klein
• Inventors: Klein, Rita J.
• Granted Patent: US 6,693,366 B2
• Time in Patent Office: Days
• US Class Current: 438/758
• CPC Class Codes: C23C 18/165 Multilayered product layered product B32B
• CPC Class Codes: C23C 18/44 using reducing agents
• CPC Class Codes: H01L 21/288 from a liquid, e.g. electrolytic deposition
• CPC Class Codes: H01L 21/7687 Thin films associated with contacts of capacitors
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material
• CPC Class Codes: H01L 28/65 comprising a noble metal or a noble metal oxide, e.g. platinum (Pt), ruthenium (Ru), ruthenium dioxide (RuO2), iridium (Ir), iridium dioxide (IrO2)
• CPC Class Codes: H01L 28/75 comprising two or more layers, e.g. comprising a barrier layer and a metal layer
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor

Abstract

A method for forming an oxidation barrier including at least partially immersing a semiconductor device structure in an electroless plating bath that includes at least one metal salt and at least one reducing agent. The reaction of the at least one metal salt with the at least one reducing agent simultaneously deposits metal and a dopant thereof. The oxidation barrier may be used to form conductive structures of semiconductor device structures, such as a capacitor electrode, or may be formed adjacent conductive or semiconductive structures of semiconductor device structures to prevent oxidation thereof. The oxidation barrier is particularly useful for preventing oxidation during the formation and annealing of a dielectric structure from a high dielectric constant material, such as Ta₂O₅ or BST.

Claims

1. A semiconductor device structure comprising:

a substrate with an active device region thereon; and

at least one layer comprising a doped metal or a doped metal alloy disposed over said substrate,

said at least one layer configured and located on said substrate so as to prevent oxygen diffusion into said active device region.

2. The semiconductor device structure of claim 1, wherein said metal or said metal alloy comprises at least one of platinum, rhodium, iridium, ruthenium, and palladium.

3. The semiconductor device structure of claim 1, wherein said at least one layer comprises at least a portion of an electrode of a capacitor structure.

4. The semiconductor device structure of claim 1, wherein said at least one layer covers said active device region.

5. The semiconductor device structure of claim 1, further comprising:

a dielectric layer over said at least one layer.

6. The semiconductor device structure of claim 5, wherein said dielectric layer comprises at least one of Ta₂O₅ and barium strontium titanate.

7. The semiconductor device structure of claim 5, wherein said dielectric layer contacts said at least one layer.

8. The semiconductor device structure of claim 5, wherein said dielectric layer is separated from said at least one layer by a conductive layer.

9. The semiconductor device structure of claim 1, wherein said doped metal or doped metal alloy is boron doped.

10. The semiconductor device structure of claim 10, wherein boron comprises about 0.1% to about 5.0% by weight of said doped metal or said doped metal alloy.

11. The semiconductor device structure of claim 1, wherein said doped metal or doped metal alloy is phosphorus-doped.

12. The semiconductor device structure of claim 1, wherein said at least one layer has a thickness of about 100 Å

.

13. The semiconductor device structure of claim 1, wherein said at least one layer has a thickness of about 500 Å

.

15. The oxidation resistant semiconductor device structure of claim 14, wherein said first conductive or semiconductive component comprises a bottom electrode of a capacitor.

16. The oxidation resistant semiconductor device structure of claim 14, wherein said second conductive component comprises a top electrode of a capacitor.

17. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer is disposed between said first conductive or semiconductive component and said second conductive component.

18. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer is disposed on said second conductive component.

19. The oxidation resistant semiconductor device structure of claim 14, wherein said doped metal or metal alloy comprises at least one of platinum, rhodium, iridium, ruthenium, and palladium.

20. The oxidation resistant semiconductor device structure of claim 14, further comprising a dielectric layer above said at least one oxidation barrier layer.

21. The oxidation resistant semiconductor device structure of claim 20, wherein said dielectric layer comprises at least one of Ta₂O₅ and barium strontium titanate.

22. The oxidation resistant semiconductor device structure of claim 14, wherein said dielectric layer contacts said at least one oxidation barrier layer.

23. The oxidation resistant semiconductor device structure of claim 14, wherein said dielectric layer is separated from said at least one oxidation barrier layer by said second conductive component.

24. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer comprises at least one layer of boron-doped metal or metal alloy.

25. The oxidation resistant semiconductor device structure of claim 24, wherein boron comprises about 0.1% to about 5.0% by weight of the oxidation barrier layer.

26. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer comprises at least one layer of phosphorus-doped metal or metal alloy.

27. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer has a thickness of about 100 Å

.

28. The oxidation resistant semiconductor device structure of claim 14, wherein said at least one oxidation barrier layer has a thickness of about 500 Å

.

30. The stacked capacitor of claim 29, wherein said doped metal or said doped metal alloy comprises at least one of platinum, rhodium, iridium, ruthenium, and palladium.

31. The stacked capacitor of claim 29, wherein at least one layer of said oxygen diffusion barrier covers said active device region.

32. The stacked capacitor of claim 29, wherein said at least one dielectric layer comprises at least one of Ta₂O₅ and barium strontium titanate.

33. The stacked capacitor of claim 29, wherein said at least one dielectric layer contacts said oxygen diffusion barrier.

34. The stacked capacitor of claim 29, wherein said dielectric layer is separated from said oxygen diffusion barrier by said conductive layer.

35. The stacked capacitor of claim 29, wherein said doped metal or said doped metal alloy is doped with boron.

36. The stacked capacitor of claim 35, wherein said boron comprises about 0.1% to about 5.0% of the weight of said doped metal or said doped metal alloy.

37. The stacked capacitor of claim 29, wherein said doped metal or said doped metal alloy is doped with phosphorus.

38. The stacked capacitor of claim 29, wherein said at least one layer has a thickness of about 100 Å

.

39. The stacked capacitor of claim 29, wherein said at least one layer has a thickness of about 500 Å

.

14. An oxidation resistant semiconductor device structure comprising:

a substrate having a first conductive or semiconductive component thereon;

a second conductive component above said first conductive or semiconductive component; and

at least one oxidation barrier layer comprising a doped metal or a doped metal alloy adjacent said second conductive component.

29. A stacked capacitor structure comprising:

a substrate including an active device region;

an oxygen diffusion barrier comprising at least one layer of doped metal or doped metal alloy;

a conductive layer above said active device region and proximate said oxygen diffusion barrier; and

at least one dielectric layer above said first conductive layer.

40. An electroless plating bath for depositing a conductive layer on a semiconductor device structure, comprising an aqueous metal solution including at least one metal salt and at least one reducing agent that will deposit a doped conductive layer that prevents oxygen diffusion when contacted with a semiconductor device structure.

41. The electroless plating bath of claim 40, wherein said at least one metal salt comprises a salt of at least one of platinum, rhodium, iridium, ruthenium, and palladium.

42. The electroless plating bath of claim 40, wherein said at least one reducing agent includes at least one of dimethylamineborane, potassium borohydride, sodium borohydride, and hydrzine.

43. The electroless plating bath of claim 40, further comprising a complexing agent.