Nonvolatile Nanotube Diodes and Nonvolatile Nanotube Blocks and Systems Using Same and Methods of Making Same

• US 20090184389A1
• Filed: 01/20/2009
• Published: 07/23/2009
• Est. Priority Date: 05/09/2005
• Status: Active Grant

• Current Assignee: Nantero Incorporated
• Original Assignee: Nantero Incorporated
• Inventors: RUECKES, Thomas, BERTIN, Claude L., GHENCIU, Eliodor G., MANNING, H. Montgomery
• Granted Patent: US 9,287,356 B2
• Time in Patent Office: Days
• US Class Current: 257/476
• 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 11/56 using storage elements with more than two stable states represented by steps, e.g. of voltage, current, phase, frequency
• CPC Class Codes: G11C 13/0007 comprising metal oxide memory material, e.g. perovskites
• CPC Class Codes: G11C 13/003 Cell access
• CPC Class Codes: G11C 13/004 Reading or sensing circuits or methods
• CPC Class Codes: G11C 13/0069 Writing or programming circuits or methods
• CPC Class Codes: G11C 13/0097 Erasing, e.g. resetting, circuits or methods
• CPC Class Codes: G11C 13/025 using fullerenes, e.g. C60, or nanotubes, e.g. carbon or silicon nanotubes
• CPC Class Codes: G11C 2013/009 Write using potential difference applied between cell electrodes
• CPC Class Codes: G11C 2213/19 Memory cell comprising at least a nanowire and only two terminals
• CPC Class Codes: G11C 2213/35 Material including carbon, e.g. graphite, grapheme
• CPC Class Codes: G11C 2213/71 Three dimensional array
• CPC Class Codes: G11C 2213/72 Array wherein the access device being a diode
• CPC Class Codes: G11C 2213/75 Array having a NAND structure comprising, for example, memory cells in series or memory elements in series, a memory element being a memory cell in parallel with an access transistor
• CPC Class Codes: G11C 2213/79 Array wherein the access device being a transistor
• CPC Class Codes: H01L 21/8221 Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 2224/80001 by connecting a bonding area directly to another bonding area, i.e. connectorless bonding, e.g. bumpless bonding
• CPC Class Codes: H01L 23/5256 comprising fuses, i.e. connections having their state changed from conductive to non-conductive
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688
• CPC Class Codes: H01L 29/0665 : the shape of the body defining a nanostructure nanotechnology per se B82B
• CPC Class Codes: H01L 29/0673 : oriented parallel to a substrate
• CPC Class Codes: H01L 29/0676 : oriented perpendicular or at an angle to a substrate
• CPC Class Codes: H01L 29/068 : comprising a junction
• CPC Class Codes: H01L 29/125 : Quantum wire structures
• CPC Class Codes: H01L 29/1606 : Graphene
• CPC Class Codes: H01L 29/861 : Diodes
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00011 : Not relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H10B 63/00 : Resistance change memory devices, e.g. resistive RAM [ReRAM] devices
• 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: H10K 85/221 : Carbon nanotubes

Abstract

A non-volatile nanotube switch and memory arrays constructed from these switches are disclosed. A non-volatile nanotube switch includes a conductive terminal and a nanoscopic element stack having a plurality of nanoscopic elements arranged in direct electrical contact, a first comprising a nanotube fabric and a second comprising a carbon material, a portion of the nanoscopic element stack in electrical contact with the conductive terminal. Control circuitry is provided in electrical communication with and for applying electrical stimulus to the conductive terminal and to at least a portion of the nanoscopic element stack. At least one of the nanoscopic elements is capable of switching among a plurality of electronic states in response to a corresponding electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack. For each electronic state, the nanoscopic element stack provides an electrical pathway of corresponding resistance.

Claims

1. A non-volatile nanotube switch, comprising:

a conductive terminal;

a nanoscopic element stack having a plurality of nanoscopic elements arranged in electrical contact, a first of the nanoscopic elements comprising a nanotube fabric and a second of the nanoscopic elements comprising a carbon material, at least a portion of the nanoscopic element stack in electrical contact with at least a portion of the conductive terminal;

control circuitry in electrical communication with and for applying electrical stimulus to the conductive terminal and to at least a portion of the nanoscopic element stack,

wherein at least one of the nanoscopic elements is capable of switching among a plurality of electronic states in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack; and

wherein for each electronic state, the nanoscopic element stack provides an electrical pathway of corresponding resistance.

2. The switch of claim 1 wherein the nanotube fabric includes a multi-layered nanotube fabric having a thickness of approximately 5 to 500 nm

3. The switch of claim 1 wherein the nanotube fabric includes a substantially single-layered nanotube fabric having a thickness of approximately 1 to 5 nm

4. The switch of claim 1 wherein the carbon material comprises one or more allotropes of carbon.

5. The switch of claim 4 wherein the one or more allotropes of carbon includes at least one of amorphous carbon, graphene, graphite, diamond, fullerenes, and nanoscopic carbon particles.

6. The switch of claim 1 wherein the carbon material forms an electrically conductive interface between the nanotube fabric and the conductive terminal.

7. The switch of claim 1 wherein the nanoscopic element stack includes a third nanoscopic element comprising a nanotube fabric.

8. The switch of claim 1 wherein an interface element is interposed between the conductive terminal and the nanoscopic element stack, the interface element selected to provide a predetermined electrically resistive pathway between the conductive terminal and the nanoscopic element stack.

9. The switch of claim 8 wherein the interface element comprises at least one of SiO, SiN, alumina, silicon, germanium, another dielectric material, and another semiconductor material.

10. The switch of claim 1 wherein the first nanoscopic element comprising nanotube fabric is substantially interposed between the conductive terminal and the second nanoscopic element comprising carbon material.

11. The switch of claim 1 wherein the second nanoscopic element comprising carbon material is substantially interposed between the conductive terminal and the first nanoscopic element comprising nanotube fabric.

12. The switch of claim 1 wherein the conductive terminal comprises an electrically conducting material including at least one of W, TiN, WN, TiCN, Ru, Ti, Cr, Al, AlCu, Au, Pd, Ni, Cu, Mo, Ag, In, Ir, Pb, Sn, TiAu, TiCu, TiPd, PbIn, TiW, a conductive nitride, a conductive oxide, and a conductive silicide.

13. The switch of claim 1 wherein the nanotube fabric further includes nanoscopic particles comprising one or more of Si, Ge, Cu, W, Ti and other non-carbon ions.

14. The switch of claim 1 wherein for a first of the plurality of electronic states, the nanoscopic element stack has an electrical resistance between approximately 100 kΩ

and 1 MΩ

.

15. The switch of claim 1 wherein for a second of the plurality of electronic states, the nanoscopic element stack has an electrical resistance of approximately 100 MΩ

.

16. The switch of claim 1 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a voltage of less than approximately 5 volts.

17. The switch of claim 1 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a SET current of approximately 1-3 μ

A.

18. The switch of claim 1 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a RESET current of approximately 10-50 μ

A.

19. The switch of claim 1 further comprising a second conductive terminal, wherein the nanoscopic element stack is substantially interposed between the conductive terminal and the second conductive terminal.

20. The switch of claim 1, wherein the carbon material and the conductive terminal are physically separated by an insulating material and wherein the first of the nanoscopic elements comprises a nanotube fabric trace forming an electrically conductive pathway between the carbon material and the conductive terminal.

21. A non-volatile nanotube memory array, comprising:

a plurality of nanotube switches, each switch having a conductive terminal and a nanoscopic element stack;

wherein the nanoscopic element stack comprises a plurality of nanoscopic elements arranged in electrical contact, a first of the nanoscopic elements comprising a nanotube fabric and a second of the nanoscopic elements comprising a carbon material, at least a portion of the nanoscopic element stack in electrical contact with at least a portion of the conductive terminal;

control circuitry in electrical communication with and for applying electrical stimulus to one or more of the plurality of nanotube switches;

wherein in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the one or more of the plurality of switches, a portion of the corresponding nanoscopic element stack switches among a plurality of electronic states; and

wherein, for each electronic state, the corresponding nanoscopic element stack provides an electrical pathway of corresponding resistance.

22. The switch of claim 21 wherein the nanotube fabric includes a multi-layered nanotube fabric having a thickness of approximately 5 to 500 nm

23. The switch of claim 21 wherein the nanotube fabric includes a substantially single-layered nanotube fabric having a thickness of approximately 1 to 5 nm

24. The switch of claim 21 wherein the carbon material comprises one or more allotropes of carbon.

25. The switch of claim 21 wherein the carbon material forms an electrically conductive interface between the nanotube fabric and the conductive terminal.

26. The switch of claim 21 wherein an interface element is interposed between the conductive terminal and the nanoscopic element stack, the interface element selected to provide a predetermined electrically resistive pathway between the conductive terminal and the nanoscopic element stack.

27. The switch of claim 26 wherein the interface element comprises at least one of SiO, SiN, alumina, silicon, germanium, another dielectric material, and another semiconductor material.

28. The switch of claim 21 wherein the first nanoscopic element comprising nanotube fabric is substantially interposed between the conductive terminal and the second nanoscopic element comprising carbon material.

29. The switch of claim 21 wherein the second nanoscopic element comprising carbon material is substantially interposed between the conductive terminal and the first nanoscopic element comprising nanotube fabric.

30. The switch of claim 21 wherein the nanotube fabric further includes nanoscopic particles comprising one or more of Si, Ge, Cu, W, Ti and other non-carbon ions.

31. The switch of claim 21 wherein for a first of the plurality of electronic states, the nanoscopic element stack has an electrical resistance between approximately 100 k Ω

and 1 MΩ

.

32. The switch of claim 21 wherein for a second of the plurality of electronic states, the nanoscopic element stack has an electrical resistance of approximately 100 MΩ

.

33. The switch of claim 21 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a voltage of less than approximately 5 volts.

34. The switch of claim 21 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a SET current of approximately 1-3 μ

A.

35. The switch of claim 21 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a RESET current of approximately 10-50 μ

A.

36. A non-volatile nanotube memory array, comprising:

an array of conductive terminals;

a nanoscopic element stack having a plurality of nanoscopic elements arranged in electrical contact, a first of the nanoscopic elements comprising a substantially planar nanotube fabric and a second of the nanoscopic elements comprising a substantially planar carbon material conformally disposed in relation to the first nanoscopic element, at least a portion of the nanoscopic element stack in electrical contact with at least a portion of the conductive terminal;

control circuitry in electrical communication with and for applying electrical stimulus to one or more selected conductive terminals and to at least a portion of the nanoscopic element stack,

wherein in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the one or more selected conductive terminals and the portion of the nanoscopic element stack, the portion of the nanoscopic element stack switches among a plurality of electronic states; and

wherein, for each electronic state, the nanoscopic element stack provides an electrical pathway of corresponding resistance.

37. The memory array of claim 36 wherein the nanotube fabric includes a multi-layered nanotube fabric having a thickness of approximately 5 to 500 nm

38. The memory array of claim 36 wherein the nanotube fabric includes a substantially single-layered nanotube fabric having a thickness of approximately 1 to 5 nm

39. The memory array of claim 36 wherein the carbon material comprises one or more allotropes of carbon.

40. The memory array of claim 39 wherein the one or more allotropes of carbon includes at least one of amorphous carbon, graphene, graphite, diamond, fullerenes, and nanoscopic carbon particles.

41. The memory array of claim 36 wherein the carbon material forms an electrically conductive interface between the nanotube fabric and the selected conductive terminal.

42. The memory array of claim 36 wherein the nanoscopic element stack includes a third nanoscopic element comprising a substantially planar nanotube fabric conformally disposed in relation to one of the first and second nanoscopic elements.

43. The memory array of claim 36 wherein an interface element is interposed between the selected conductive terminal and the nanoscopic element stack, the interface element selected to provide a predetermined electrically resistive pathway between the selected conductive terminal and the nanoscopic element stack.

44. The memory array of claim 43 wherein the interface element comprises at least one of SiO, SiN, alumina, silicon, germanium, another dielectric material, and another semiconductor material.

45. The memory array of claim 36 wherein the nanotube fabric is substantially interposed between the conductive terminals and the carbon material.

46. The memory array of claim 36 wherein the carbon material is substantially interposed between the conductive terminals and the nanotube fabric.

47. The memory array of claim 36 wherein the conductive terminals comprise an electrically conducting material including at least one of W, TiN, WN, TiCN, Ru, Ti, Cr, Al, AlCu, Au, Pd, Ni, Cu, Mo, Ag, In, Ir, Pb, Sn, TiAu, TiCu, TiPd, PbIn, TiW, a conductive nitride, a conductive oxide, and a conductive silicide.

48. The memory array of claim 36 wherein the nanotube fabric further includes nanoscopic particles comprising one or more of Si, Ge, Cu, W, Ti and other non-carbon ions.

49. The memory array of claim 36 wherein for a first of the plurality of electronic states, the portion of the nanoscopic element stack has an electrical resistance between approximately 100 kΩ

and 1 MΩ

.

50. The memory array of claim 36 wherein for a second of the plurality of electronic states, the portion of the nanoscopic element stack has an electrical resistance of approximately 100 MΩ

.

51. The memory array of claim 36 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a voltage of less than approximately 5 volts.

52. The memory array of claim 36 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a SET current of approximately 1-3 μ

A.

53. The memory array of claim 36 wherein the plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack comprises a RESET current of approximately 10-50 μ

A.

54. The memory array of claim 36, wherein the nanoscopic element stack is patterned to form a nanoscopic element trace having defined lithographic dimensions.

55. A non-volatile nanotube switch, comprising:

a conductive terminal;

a nanoscopic element stack having a first nanoscopic elements comprising a nanotube fabric and a second of the nanoscopic elements comprising an interface layer, at least a portion of the nanoscopic element stack in electrical contact with at least a portion of the conductive terminal;

control circuitry in electrical communication with and for applying electrical stimulus to the conductive terminal and to at least a portion of the nanoscopic element stack,

wherein the first nanoscopic elements is capable of switching among a plurality of electronic states in response to a corresponding plurality of electrical stimuli applied by the control circuitry to the conductive terminal and the portion of the nanoscopic element stack; and

wherein, for each electronic state, the nanoscopic element stack provides an electrical pathway of corresponding resistance.

56. The switch of claim 55 wherein the interface layer comprises one or more polycrystalline materials that at least partially penetrates the nanotube fabric.

57. The switch of claim 55 wherein the interface layer comprises at least one of Ge, W, Wn, TiN, TiCN.

58. The switch of claim 57 wherein the interface layer is formed from the selective etching of a sacrificial material layer.

59. The switch of claim 55 wherein the interface layer is constructed and arranged to substantially increase the resistance corresponding to the electrical pathway of the nanoscopic element stack.

60. The switch of claim 55 wherein the interface layer comprises a layer of Ge having a thickness between approximately 5 and 250 nm.

61. The switch of claim 55 wherein the nanoscopic element stack is in physical and electrical contact with a nanoscopic semiconductor element.

62. The switch of claim 61 wherein the nanoscopic semiconductor element comprises one of the anode and the cathode of a semiconductor diode.

63. A non-volatile nanotube switch, comprising:

a pair of conductive terminals;

a nonwoven fabric article having a plurality of nanotubes forming an electrical network, the plurality of nanotubes having a plurality of defects selected to provide pre-determined electrical characteristics of the network, the article electrically interposed between the pair of conductive terminals;

control circuitry in electrical communication with and for applying electrical stimulus to the pair of conductive terminals,

wherein the article is capable of switching among a plurality of electronic states in response to a corresponding plurality of electrical stimuli from the control circuitry; and

wherein, for each electronic state, the nonwoven fabric article provides an electrical pathway of corresponding resistance.

64. The switch of claim 63 wherein the nanotubes comprise a selected composition of single walled nanotubes and multi-walled nanotubes.

65. The switch of claim 64 wherein the proportion of single walled nanotubes to multi-walled nanotubes is selected to increase the quantity of defects comprising the plurality of defects.

66. The switch of claim 63 wherein the plurality of defects is formed from chemical treatments comprising at least one of sulfuric acid and nitric acid.

67. The switch of claim 63 wherein the plurality of defects is formed from ion implantation treatments.

68. The switch of claim 67 wherein the ion implantation provides ions that partially permeate the nonwoven fabric article.

69. The switch of claim 63 wherein the plurality of electrical stimuli from the control circuitry comprises a voltage of less than approximately 5 volts.

70. The switch of claim 63 wherein the plurality of electrical stimuli from the control circuitry comprises a SET current of approximately 1-3 μ

A and a RESET current of approximately 10-50 μ

A.