Electronic apparatus having a core conductive structure within an insulating layer

• US 7,504,674 B2
• Filed: 08/29/2005
• Issued: 03/17/2009
• Est. Priority Date: 08/05/2003
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Farrar, Paul A.
• Primary Examiner(s): Ngo; Ngan
• Assistant Examiner(s): LIU, BENJAMIN T
• Application Number:
  US11/215,367
• Publication Number:
  US 20060006548A1
• Time in Patent Office: 1,296 Days
• Field of Search: 257/751, 257/753, 257/758, 257/762, 257/773, 257/774, 257/E23.144, 257/E23.145, 257/E23.154, 257/E23.155, 257/767, 257/E23.011, 257/E23.146
• US Class Current: 257/213
• CPC Class Codes: H01L 21/76801 characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 21/76825 by exposing the layer to particle radiation, e.g. ion implantation, irradiation with UV light or electrons etc. plasma treatment H01L21/76826
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76849 the layer being positioned on top of the main fill metal
• CPC Class Codes: H01L 21/76859 by ion implantation
• CPC Class Codes: H01L 21/76867 characterized by methods of formation other than PVD, CVD or deposition from a liquids PVD H01L21/2855; CVD H01L21/28556; deposition from liquids H01L21/288
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 21/76874 for electroless plating
• CPC Class Codes: H01L 21/76879 by selective deposition of conductive material in the vias, e.g. selective C.V.D. on semiconductor material, plating plating on semiconductors in general H01L21/288

Abstract

Electronic devices are constructed by a method that includes forming a first conductive layer in an opening in a multilayer dielectric structure supported by a substrate, forming a core conductive layer on the first conductive layer, subjecting the core conductive layer to a H₂ plasma treatment, and depositing a capping adhesion/barrier layer on the core conductive layer after the H₂ plasma treatment. The multilayer dielectric structure provides an insulating layer for around the core conducting layer. The H₂ plasma treatment removes unwanted oxide from the surface region of the core conducting layer such that the interface between the core conducting layer and the capping adhesion/barrier is substantially free of oxides.

Claims

1. An electronic device comprising:

an insulating layer; and

a conductive structure within the insulating layer, the conductive structure including;

a first conducting layer structured as two conductive layers;

a core conductor disposed on and within the first conducting layer; and

a capping layer disposed on and covering the core conductor and the first conducting layer, the capping layer being a conductor, the capping layer in contact with at least a center portion of the core conductor and a top portion of the two conductive layers of the first conducting layer such that contact with the first conducting layer is limited to the top portion and inner surfaces of the first conducting layer, the inner surfaces containing the core conductor, the capping layer having at least one property from a group of an adhesion property and a barrier property, wherein an interface between the capping layer and the core conductor is substantially free of an oxide.

2. The electronic device of claim 1, wherein a top surface of the core conductor is substantially at a level with a top surface of the insulating layer.

3. The electronic device of claim 1, wherein the two conductive layers are structured as a first layer and a seed layer, the first layer having at least one property from the group of an adhesion property and a barrier property.

4. The electronic device of claim 3, wherein the first layer includes a refractory metal, a compound of nitrogen and a tantalum alloy, or a compound of nitrogen and a tungsten alloy.

5. The electronic device of claim 1, wherein the core conductor includes copper, silver, a copper alloy, or a silver alloy.

6. The electronic device of claim 1, wherein the capping layer includes titanium, zirconium, hafnium, or nitrides of titanium, zirconium, or hafnium.

7. The electronic device of claim 1, wherein the capping layer has a thickness ranging from about 5 Å

to about 40 Å

.

8. The electronic device of claim 1, wherein the insulating layer includes a polymer layer, a foamed polymer layer, or a fluorinated polymer layer.

9. The electronic device of claim 1, wherein the insulating layer includes a polyimide layer, a foamed polyimide layer, or a fluorinated polyimide layer.

10. The electronic device of claim 1, wherein the insulating layer includes an oxide layer, a fluorinated oxide layer, a silicon dioxide layer, or an aerogel layer.

11. The electronic device of claim 1, wherein the insulating layer is disposed on a dielectric structure having a via to connect to lower level metallizations or devices in a substrate.

12. The electronic device of claim 1, wherein a portion of the insulating layer includes an opening between the core conductor and another conductor to provide an air bridge structure.

13. The electronic device of claim 1, wherein the conductive structure includes a wiring structure in an integrated circuit.

14. The electronic device of claim 1, wherein the conductive structure includes a wiring structure in a memory device.

15. The electronic device of claim 1, wherein the conductive structure includes a wiring structure in a controller coupled to an integrated circuit in an electronic system.

16. The electronic device of claim 1, wherein the core conductive structure essentially consists of aluminum, silver, gold, or combinations thereof, the core conductive structure having a hydrogen-plasma treated surface to provide the interface between the capping layer and the core conductor substantially free of an oxide.

17. An integrated circuit comprising:

one or more active devices in a substrate; and

a wiring structure coupled to at least one of the active devices, at least a portion of the wiring structure including;

a first level via in a first insulator layer;

a first conducting layer formed over and connecting to the first level via in the first insulator layer, the first conducting layer structured as two conductive layers;

a core conductor disposed on and within the first conducting layer; and

a capping layer disposed on and covering the core conductor and the first conducting layer, the capping layer being a conductor, the capping layer in contact with at least a center portion of the core conductor and a top portion of the. two conductive layers of the first conducting layer such that contact with the first conducting layer is limited to the top portion and inner surfaces of the first conducting layer, the inner surfaces containing the core conductor, the capping layer, the first conducting layer, and the core conductor being within a second insulator layer, the capping layer having at least one property from a group of an adhesion property and a barrier property, wherein an interface between the capping layer and the core conductor is substantially free of an oxide.

18. The integrated circuit of claim 17, wherein the two conductive layers are structured as a first layer and a seed layer, the first layer having at least one property from a group of an adhesion property and a barrier property.

19. The integrated circuit of claim 18, wherein the first layer includes a refractory metal, a compound of nitrogen and a tantalum alloy, or a compound of nitrogen and a tungsten alloy.

20. The integrated circuit of claim 17, wherein the core conductor includes copper, silver, a copper alloy, or a silver alloy.

21. The integrated circuit of claim 17, wherein the capping layer includes titanium, zirconium, hafnium, or nitrides of titanium, zirconium, or hafnium.

22. The integrated circuit of claim 17, wherein the capping layer has a thickness ranging from about 5 Å

to about 40 Å

.

23. The integrated circuit of claim 17, wherein the second insulator layer includes a polymer layer, a foamed polymer layer, or a fluorinated polymer layer.

24. The integrated circuit of claim 17, wherein the second insulator layer includes a polyimide layer, a foamed polyimide layer, or a fluorinated polyimide layer.

25. The integrated circuit of claim 17, wherein the second insulator layer includes an oxide layer, a fluorinated oxide layer, or an aerogel layer.

26. The integrated circuit of claim 17, wherein a top surface of the core conductor is substantially at a level with a top surface of the second insulator layer.

27. The integrated circuit of claim 17, further including a gap between two or more core conductors to provide an air bridge structure.

28. A memory device comprising:

an array of memory cells in a substrate; and

a wiring structure in the substrate coupling to the array of memory cells, at least a portion of the wiring structure including;

a first level via in a first insulator layer;

a first conducting layer formed over and connecting to the first level via in the first insulator layer, the first conducting layer structured as two conductive layers;

a core conductor disposed on and within the first conducting layer; and

a capping layer disposed on and covering the core conductor and the first conducting layer, the capping layer being a conductor, the capping layer in contact with at least a center portion of the core conductor and a top portion of the two conductive layers of the first conducting layer such that contact with the first conducting layer is limited to the top portion and inner surfaces of the first conducting layer, the inner surfaces containing the core conductor, the capping layer, the first conducting layer, and the core conductor being within a second insulator layer, the capping layer having at least one property from a group of an adhesion property and a barrier property, wherein an interface between the capping layer and the core conductor is substantially free of an oxide.

29. The memory device of claim 28, wherein the two conductive layers are structured as a first layer and a seed layer, the first layer having at least one property from a group of an adhesion property and a barrier property.

30. The memory device of claim 29, wherein the first layer includes a refractory metal, a compound of nitrogen and a tantalum alloy, or a compound of nitrogen and a tungsten alloy.

31. The memory device of claim 28, wherein the core conductor includes copper, silver, a copper alloy, or a silver alloy.

32. The memory device of claim 28, wherein the capping layer includes titanium, zirconium, hafnium, or nitrides of titanium, zirconium, or hafnium.

33. The memory device of claim 28, wherein the capping layer has a thickness ranging from about 5 Å

to about 40 Å

.

34. The memory device of claim 28, wherein the second insulator layer includes a polymer layer, a foamed polymer layer, or a fluorinated polymer layer.

35. The memory device of claim 28, wherein the second insulator layer includes a polyimide layer, a foamed polyimide layer, or a fluorinated polyimide layer.

36. The memory device of claim 28, wherein the second insulator layer includes an oxide layer, a fluorinated oxide layer, or an aerogel layer.

37. The memory device of claim 28, wherein a top surface of the core conductor is substantially at a level with a top surface of the second insulator layer.

38. An electronic system comprising:

a controller; and

one or more integrated circuits coupled to the controller, at least one integrated circuit having a wiring structure with at least a portion of the wiring structure including;

an insulating layer;

a conductive structure within the insulating layer, the conductive structure having;

a first conducting layer structured as two conductive layers;

a core conductor disposed on and within the first conducting layer; and

a capping layer disposed on and covering the core conductor and the first conducting layer, the capping layer being a conductor, the capping layer in contact with at least a center portion of the core conductor and a top portion of the two conductive layers of the first conducting layer such that contact with the first conducting layer is limited to the top portion and inner surfaces of the first conducting layer, the inner surfaces containing the core conductor, the capping layer having at least one property from a group of an adhesion property and a barrier property, wherein an interface between the capping layer and the core conductor is substantially free of an oxide.

39. The electronic system of claim 38, wherein a top surface of the core conductor is substantially at a level with a top surface of the insulating layer.

40. The electronic system of claim 38, wherein the two conductive layers are structured as a first layer and a seed layer, the first layer having at least one property from a group of an adhesion property and a barrier property.

41. The electronic system of claim 40, wherein the first layer includes a refractory metal, a compound of nitrogen and a tantalum alloy, or a compound of nitrogen and a tungsten alloy.

42. The electronic system of claim 38, wherein the core conductor includes copper, silver, a copper alloy, or a silver alloy.

43. The electronic system of claim 38, wherein the capping layer includes titanium, zirconium, hafnium, or nitrides of titanium, zirconium, or hafnium.

44. The electronic system of claim 38 wherein the capping layer has a thickness ranging from about 5 Å

to about 40 Å

.

45. The electronic system of claim 38, wherein the insulating layer includes a polymer layer, a foamed polymer layer, or a fluorinated polymer layer.

46. The electronic system of claim 38, wherein the insulating layer includes a polyimide layer, a foamed polyimide layer, or a fluorinated polyimide layer.

47. The electronic system of claim 38, wherein the insulating layer includes an oxide layer, a fluorinated oxide layer, a silicon dioxide layer, or an aerogel layer.

48. The electronic system of claim 38, wherein the insulating layer is disposed on a dielectric structure having a via to connect to lower level metallizations or devices in a substrate.

49. The electronic system of claim 38, wherein the controller includes a processor.

50. The electronic system of claim 38, wherein the electronic system includes a computer.