Deposition of gate metallization for active matrix liquid crystal display (AMLCD) applications

• US 20030194825A1
• Filed: 04/10/2002
• Published: 10/16/2003
• Est. Priority Date: 04/10/2002
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Maydan, Dan, Law, Kam, Harshbarger, William Reid, Shang, Quan Yuan
• Application Number:
  US10/119,631
• Publication Number:
  US 20030194825A1
• Time in Patent Office: Days
• US Class Current: 438/30
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 29/66757 Lateral single gate single channel transistors with non-inverted structure, i.e. the channel layer is formed before the gate
• CPC Class Codes: H01L 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate

Abstract

A method of gate metal layer deposition using a cyclical deposition process for thin film transistor applications is described. The cyclical deposition process comprises alternately adsorbing a metal-containing precursor and a reducing gas on a substrate. Thin film transistors, such as a bottom-gate transistor or a top-gate transistor, including a gate layer, may be formed using such cyclical deposition techniques.

Claims

1. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate having a dielectric layer deposited over source regions and drain regions formed thereon; and

depositing a gate metal layer on the dielectric layer using a cyclical deposition process comprising a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas to a process chamber and modulating the flow of the inert gas with an alternating period of exposure to one of either a metal-containing precursor and a reducing gas.

2. The method of claim 1 wherein the gate metal layer comprises a material selected from the group consisting of aluminum (Al), tungsten (W), chromium (Cr) and molybdenum (Mo).

3. The method of claim 1 wherein the metal-containing precursor comprises a compound selected from the group consisting of dimethyl aluminum hydride (DMAH), tungsten hexafluoride (WF₆), tungsten hexacarbonyl (W(CO)₆) and chromium tetrachloride (CrCl₄).

4. The method of claim 1 wherein the reducing gas comprises a gas selected from the group consisting of silane (SiH₄), disilane (Si₂H₆), dichlorosilane (SiCl₂H₂), ammonia (NH₃), hydrazine (N₂H₄), monomethyl hydrazine (CH₃N₂H₃), dimethyl hydrazine (C₂H₆N₂H₂), t-butyl hydrazine (C₄H₉N₂H₃), phenyl hydrazine (C₆H₅N₂H₃), 2,2′

-azoisobutane ((CH₃)₆C₂N₂) ethylazide (C₂H₅N₃), borane (BH₃), diborane (B₂H₆), triborane (B₃H₉), tetraborane (B₄H₁₂), pentaborane (B₅H₁₅), hexaborane (B₆H₁₈), heptaborane (B₇H₂₁), octaborane (B₈H₂₄), nanoborane (B₉H₂₇) and decaborane (B₁₀H₃₀).

5. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate;

depositing a gate metal layer on the substrate using a cyclical deposition process comprising a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas to a process chamber and modulating the flow of the inert gas with an alternating period of exposure to one of either a metal-containing precursor and a reducing gas;

defining one or more gates in the gate metal layer; and

forming source regions and drain regions over the one or more gates defined in the gate metal layer.

6. The method of claim 5 wherein the gate metal layer comprises a material selected from the group consisting of aluminum (Al), tungsten (W), chromium (Cr) and molybdenum (Mo).

7. The method of claim 5 wherein the metal-containing precursor comprises a compound selected from the group consisting of dimethyl aluminum hydride (DMAH), tungsten hexafluoride (WF₆), tungsten hexacarbonyl (W(CO)₆) and chromium tetrachloride (CrCl₄).

8. The method of claim 5 wherein the reducing gas comprises a gas selected from the group consisting of silane (SiH₄), disilane (Si₂H₆), dichlorosilane (SiCl₂H₂), ammonia (NH₃), hydrazine (N₂H₄), monomethyl hydrazine (CH₃N₂H₃), dimethyl hydrazine (C₂H₆N₂H₂), t-butyl hydrazine (C₄H₉N₂H₃), phenyl hydrazine (C₆H₅N₂H₃), 2,2′

-azoisobutane ((CH₃)₆C₂N₂), ethylazide (C₂H₅N₃), borane (BH₃), diborane (B₂H₆), triborane (B₃H₉), tetraborane (B₄H₁₂), pentaborane (B₅H₁₅), hexaborane (B₆H₁₈), heptaborane (B₇H₂₁), octaborane (B₈H₂₄), nanoborane (B₉H₂₇) and decaborane (B₁₀H₃₀).

9. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process comprising a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas to a process chamber and modulating the flow of the inert gas with an alternating period of exposure to one of either a metal-containing precursor and a reducing gas.

10. The method of claim 9 wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration.

11. The method of claim 9 wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration.

12. The method of claim 9 wherein the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

13. The method of claim 9 wherein at least one period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

14. The method of claim 9 wherein the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

15. The method of claim 9 wherein at least one period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

16. The method of claim 9 wherein a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

17. The method of claim 9 wherein at least one period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

18. The method of claim 9 wherein a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

19. The method of claim 9 wherein at least one period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

20. The method of claim 9 wherein the gate metal layer comprises a material selected from the group consisting of aluminum (Al), tungsten (W), chromium (Cr) and molybdenum (Mo).

21. The method of claim 9 wherein the metal-containing precursor comprises a compound selected from the group consisting of dimethyl aluminum hydride (DMAH), tungsten hexafluoride (WF₆), tungsten hexacarbonyl (W(CO)₆) and chromium tetrachloride (CrCl₄).

22. The method of claim 9 wherein the reducing gas comprises a gas selected from the group consisting of silane (SiH₄), disilane (Si₂H₆), dichlorosilane (SiCl₂H₂), ammonia (NH₃), hydrazine (N₂H₄), monomethyl hydrazine (CH₃N₂H₃), dimethyl hydrazine (C₂H₆N₂H₂), t-butyl hydrazine (C₄H₉N₂H₃), phenyl hydrazine (C₆H₅N₂H₃), 2,2′

-azoisobutane ((CH₃)₆C₂N₂), ethylazide (C₂H₅N₃), borane (BH₃), diborane (B₂H₆), triborane (B₃H₉), tetraborane (B₄H₁₂), pentaborane (B₅H₁₅), hexaborane (B₆H₁₈), heptaborane (B₇H₂₁), octaborane (B₈H₂₄), nanoborane (B₉H₂₇) and decaborane (B₁₀H₃₀).

23. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, and wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration.

24. The method of claim 23 wherein the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

25. The method of claim 23 wherein at least one period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

26. The method of claim 23 wherein the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

27. The method of claim 23 wherein at least one period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

28. The method of claim 23 wherein a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

29. The method of claim 23 wherein at least one period of flow of the inert gas between the period of exposure to the metal-containing precursor and the reducing gas during each deposition cycle of the cyclical deposition process has a different duration.

30. The method of claim 23 wherein a period of flow of the inert gas between the period of exposure to the reducing gas and the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

31. The method of claim 23 wherein at least one period of flow of the inert gas between the period of exposure to the reducing gas and the metal-containing precursor for one or more deposition cycles of the cyclical deposition process has a different duration.

32. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, and wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration.

33. The method of claim 32 wherein the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

34. The method of claim 32 wherein at least one period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

35. The method of claim 32 wherein the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

36. The method of claim 32 wherein at least one period of exposure to the reducing gas during one or more deposition cycle of the cyclical deposition process has a different duration.

37. The method of claim 32 wherein the period of flow of the inert gas between the period of exposure to the metal-containing precursor and the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

38. The method of claim 32 wherein at least one period of flow of the inert gas between the period of exposure to the metal-containing precursor and the reducing gas during each deposition cycle of the cyclical deposition process has a different duration.

39. The method of claim 32 wherein the period of flow of the inert gas between the period of exposure to the reducing gas and the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

40. The method of claim 32 wherein at least one period of flow of the inert gas between the period of exposure to the reducing gas and the metal-containing precursor for one or more deposition cycles of the cyclical deposition process has a different duration.

41. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration, and wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, the period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and the period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration during each deposition cycle of the cyclical deposition process.

42. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration, and wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, the period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and the period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration during one or more deposition cycles of the cyclical deposition process.

43. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration, and wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, the period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and the period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration during each deposition cycle of the cyclical deposition process.

44. A method of forming a transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process, wherein the cyclical deposition process includes a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas in a process chamber and modulating the flow of the inert gas with alternating periods of exposure to one of a metal-containing precursor and a reducing gas, wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration, and wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, the period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and the period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the silicon-containing precursor has a different duration during one or more deposition cycles of the cyclical deposition process.

45. A method of forming a gate metal layer on a substrate, comprising:

providing a substrate; and

depositing a gate metal layer on the substrate using a cyclical deposition process comprising a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas to a process chamber and modulating the flow of the inert gas with an alternating period of exposure to one of either a metal-containing precursor and a reducing gas.

46. The method of claim 45 wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration.

47. The method of claim 45 wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration.

48. The method of claim 45 wherein the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

49. The method of claim 45 wherein at least one period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

50. The method of claim 45 wherein the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

51. The method of claim 45 wherein at least one period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

52. The method of claim 45 wherein a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

53. The method of claim 45 wherein at least one period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

54. The method of claim 45 wherein a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

55. The method of claim 45 wherein at least one period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

56. The method of claim 45 wherein the gate metal layer comprises a material selected from the group consisting of aluminum (Al), tungsten (W), chromium (Cr) and molybdenum (Mo).

57. The method of claim 45 wherein the metal-containing precursor comprises a compound selected from the group consisting of dimethyl aluminum hydride (DMAH), tungsten hexafluoride (WF₆), tungsten hexacarbonyl (W(CO)₆) and chromium tetrachloride (CrCl₄).

58. The method of claim 45 wherein the reducing gas comprises a gas selected from the group consisting of silane (SiH₄), disilane (Si₂H₆), dichlorosilane (SiCl₂H₂), ammonia (NH₃), hydrazine (N₂H₄), monomethyl hydrazine (CH₃N₂H₃), dimethyl hydrazine (C₂H₆N₂H₂), t-butyl hydrazine (C₄H₉N₂H₃), phenyl hydrazine (C₆H₅N₂H₃), 2,2′

-azoisobutane ((CH₃)₆C₂N₂), ethylazide (C₂H₅N₃), borane (BH₃), diborane (B₂H₆), triborane (B₃H₉), tetraborane (B₄H₁₂), pentaborane (B₅H₁₅), hexaborane (B₆H₁₈), heptaborane (B₇H₂₁), octaborane (B₈H₂₄), nanoborane (B₉H₂₇) and decaborane (B₁₀H₃₀).

59. A transistor for use in an active matrix liquid crystal display (AMLCD), comprising:

a substrate a gate metal layer formed thereon, the gate metal layer is formed using a cyclical deposition process comprising a plurality of cycles, wherein each cycle comprises establishing a flow of an inert gas to a process chamber and modulating the flow of the inert gas with an alternating period of exposure to one of either a metal-containing precursor and a reducing gas.

60. The transistor of claim 59 wherein the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor each have the same duration.

61. The transistor of claim 59 wherein at least one of the period of exposure to the metal-containing precursor, the period of exposure to the reducing gas, a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas, and a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor has a different duration.

62. The transistor of claim 59 wherein the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

63. The transistor of claim 59 wherein at least one period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

64. The transistor of claim 59 wherein the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

65. The transistor of claim 59 wherein at least one period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

66. The transistor of claim 59 wherein a period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas during each deposition cycle of the cyclical deposition process has the same duration.

67. The transistor of claim 59 wherein at least one period of flow of the inert gas between the period of exposure to the metal-containing precursor and the period of exposure to the reducing gas for one or more deposition cycle of the cyclical deposition process has a different duration.

68. The transistor of claim 59 wherein a period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor during each deposition cycle of the cyclical deposition process has the same duration.

69. The transistor of claim 59 wherein at least one period of flow of the inert gas between the period of exposure to the reducing gas and the period of exposure to the metal-containing precursor for one or more deposition cycle of the cyclical deposition process has a different duration.

70. The transistor of claim 59 wherein the gate metal layer comprises a material selected from the group consisting of aluminum (Al), tungsten (W), chromium (Cr) and molybdenum (Mo).

71. The transistor of claim 59 wherein the metal-containing precursor comprises a compound selected from the group consisting of dimethyl aluminum hydride (DMAH), tungsten hexafluoride (WF₆), tungsten hexacarbonyl (W(CO)₆) and chromium tetrachloride (CrCl₄).

72. The transistor of claim 59 wherein the reducing gas comprises a gas selected from the group consisting of silane (SiH₄), disilane (Si₂H₆), dichlorosilane (SiCl₂H₂), ammonia (NH₃), hydrazine (N₂H₄), monomethyl hydrazine (CH₃N₂H₃), dimethyl hydrazine (C₂H₆N₂H₂), t-butyl hydrazine (C₄H₉N₂H₃), phenyl hydrazine (C₆H₅N₂H₃), 2,2′

-azoisobutane ((CH₃)₆C₂N₂), ethylazide (C₂H₅N₃), borane (BH₃), diborane (B₂H₆), triborane (B₃H₉), tetraborane (B₄H₁₂), pentaborane (B₅H₁₅), hexaborane (B₆H₁₈), heptaborane (B₇H₂₁), octaborane (B₈H₂₄), nanoborane (B₉H₂₇) and decaborane (B₁₀H₃₀).