Electromechanical memory array using nanotube ribbons and method for making same

• US 6,919,592 B2
• Filed: 07/25/2001
• Issued: 07/19/2005
• Est. Priority Date: 07/25/2001
• Status: Expired due to Term

• Current Assignee: Nantero Incorporated
• Original Assignee: Nantero Incorporated
• Inventors: Brock, Darren K., Segal, Brent M., Rueckes, Thomas
• Primary Examiner(s): COLEMAN, WILLIAM D
• Application Number:
  US09/915,093
• Publication Number:
  US 20030021966A1
• Time in Patent Office: 1,455 Days
• Field of Search: 257/208, 257/209, 257/317, 257/320, 257/331, 257/343, 257/773, 438/668, 438/52, 438/283
• US Class Current: 257/209
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11C 13/025 using fullerenes, e.g. C60, or nanotubes, e.g. carbon or silicon nanotubes
• CPC Class Codes: G11C 2213/16 Memory cell being a nanotube, e.g. suspended nanotube
• CPC Class Codes: G11C 2213/81 Array wherein the array conductors, e.g. word lines, bit lines, are made of nanowires
• CPC Class Codes: G11C 23/00 Digital stores characterised by movement of mechanical parts to effect storage, e.g. using balls; Storage elements therefor
• CPC Class Codes: H01H 1/0094 Switches making use of nanoelectromechanical systems [NEMS]
• CPC Class Codes: H01L 21/76838 characterised by the formation and the after-treatment of the conductors etching for patterning the conductors H01L21/3213
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices
• CPC Class Codes: Y10S 977/724 Devices having flexible or movable element
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/796 for electrical or electronic purpose
• CPC Class Codes: Y10S 977/856 including etching/cutting
• CPC Class Codes: Y10S 977/888 Shaping or removal of materials, e.g. etching
• CPC Class Codes: Y10S 977/943 Information storage or retrieval using nanostructure
• CPC Class Codes: Y10T 428/24893 including particulate material
• CPC Class Codes: Y10T 428/24917 including metal layer

Abstract

Electromechanical circuits, such as memory cells, and methods for making same are disclosed. The circuits include a structure having electrically conductive traces and supports extending from a surface of the substrate, and nanotube ribbons suspended by the supports that cross the electrically conductive traces, wherein each ribbon comprises one or more nanotubes. The electro-mechanical circuit elements are made by providing a structure having electrically conductive traces and supports, in which the supports extend from a surface of the substrate. A layer of nanotubes is provided over the supports, and portions of the layer of nanotubes are selectively removed to form ribbons of nanotubes that cross the electrically conductive traces. Each ribbon includes one or more nanotubes.

Claims

1. An electromechanical circuit, comprising:

a structure having electrically conductive traces and supports extending from a surface of a substrate; and

nanotube ribbons suspended by the supports that cross the electrically conductive traces, wherein each ribbon has a cross-sectional area that is substantially rectangular.

2. The circuit of claim 1 wherein the electrically conductive traces are doped silicon traces.

3. The circuit of claim 1 wherein the electrically conductive traces are nanotubes.

4. The circuit of claim 1 wherein the electrically conductive traces are ribbons of nanotubes.

5. The circuit of claim 1 wherein the supports are rows of material and wherein the traces are substantially parallel to the rows.

6. The circuit of claim 5 wherein the traces are separated from the supports.

7. The circuit of claim 5 wherein the traces contact the supports.

8. The circuit of claim 1 wherein the supports are made from silicon nitride.

9. The circuit of claim 1 wherein the electrically conductive traces are over a layer of insulating material to electrically isolate the traces relative to one another.

10. The circuit of claim 1 wherein the electrically conductive traces are each over insulating material to electrically isolate the traces.

11. The circuit of claim 1 wherein ribbons are of a non-woven fabric of nanotubes.

12. The circuit of claim 1 wherein the ribbons are substantially a monolayer of nanotubes.

13. An electromechanical circuit, comprising:

a structure having electrically conductive traces and supports extending from a surface of a substrate; and

nanotube ribbons suspended by the supports that cross the electrically conductive traces, wherein each ribbon is flat.

14. The circuit of claim 13 wherein the electrically conductive traces are doped silicon traces.

15. The circuit of claim 13 wherein the electrically conductive traces are nanotubes.

16. The circuit of claim 13 wherein the electrically conductive traces are ribbons of nanotubes.

17. The circuit of claim 13 wherein the supports are rows of material and wherein the traces are substantially parallel to the rows.

18. The circuit of claim 13 wherein the traces are separated from the supports.

19. The circuit of claim 13 wherein the traces contact the supports.

20. The circuit of claim 13 wherein the supports are made from silicon nitride.

21. The circuit of claim 13 wherein the electrically conductive traces are over a layer of insulating material to electrically isolate the traces relative to one another.

22. The circuit of claim 13 wherein the electrically conductive traces are each over insulating material to electrically isolate the traces.

23. The circuit of claim 13 wherein ribbons are of a non-woven fabric of nanotubes.

24. The circuit of claim 13 wherein the ribbons are substantially a monolayer of nanotubes.

25. An electromechanical circuit, comprising:

a structure having electrically conductive traces and supports extending from a surface of a substrate; and

nanotube ribbons suspended by the supports that cross the electrically conductive traces, wherein each ribbon comprises a plurality of nanotubes.

26. The circuit of claim 25 wherein the electrically conductive traces are doped silicon traces.

27. The circuit of claim 25 wherein the electrically conductive traces are nanotubes.

28. The circuit of claim 25 wherein the electrically conductive traces are ribbons of nanotubes.

29. The circuit of claim 25 wherein the supports are rows of material and wherein the traces are substantially parallel to the rows.

30. The circuit of claim 25 wherein the traces are separated from the supports.

31. The circuit of claim 25 wherein the traces contact the supports.

32. The circuit of claim 25 wherein the supports are made from silicon nitride.

33. The circuit of claim 25 wherein the electrically conductive traces are over a layer of insulating material to electrically isolate the traces relative to one another.

34. The circuit of claim 25 wherein the electrically conductive traces are each over insulating material to electrically isolate the traces.

35. The circuit of claim 25 wherein ribbons are of a non-woven fabric of nanotubes.

36. The circuit of claim 25 wherein the ribbons are substantially a monolayer of nanotubes.