Method of eliminating residual carbon from flowable oxide fill

• US 20040152342A1
• Filed: 02/04/2003
• Published: 08/05/2004
• Est. Priority Date: 02/04/2003
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Li, Li, Li, Weimin
• Granted Patent: US 7,205,248 B2
• Time in Patent Office: Days
• US Class Current: 438/789
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02282 liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/31612 on a silicon body
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264

Abstract

Methods of forming an oxide layer such as high aspect ratio trench isolations, and treating the oxide substrate to remove carbon, structures formed by the method, and devices and systems incorporating the oxide material are provided.

Claims

1. A method of treating a carbon-containing oxide layer disposed on a semiconductive substrate, comprising the step of:

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

2. The method of claim 1, wherein the oxide layer comprises a fill within a gap in the substrate.

3. The method of claim 2, wherein the gap comprises an aspect ratio of about 7:

1 to about 10;

1.

4. The method of claim 2, wherein the oxide layer comprises a trench isolation area.

5. A method of treating a carbon-containing oxide layer disposed on a semiconductive substrate, comprising the step of:

exposing the oxide layer to an oxygen plasma to reduce the carbon in the oxide layer by at least about 80%.

6. A method of treating a carbon-containing oxide layer disposed on a semiconductive substrate, comprising the step of:

exposing the oxide layer to an oxygen plasma for at least about 10 seconds at a substrate temperature of up to about 800°

C.

7. The method of claim 6, wherein the oxide layer is exposed to the oxygen plasma at a substrate temperature of about 20 to about 450°

C.

8. The method of claim 6, wherein the oxide layer is exposed to the oxygen plasma for at least about 100 seconds.

9. A method of treating a carbon-containing oxide layer in a semiconductive substrate, comprising the step of:

exposing the oxide layer to an oxygen plasma for a time effective to reduce carbon in the oxide layer to a non-detectable level.

10. The method of claim 9, wherein the carbon is reduced by at least about 50%.

11. The method of claim 9, wherein the oxide layer is exposed to the oxygen plasma for at least about 100 seconds at a substrate temperature of up to about 800°

C.

12. A method of treating a carbon-containing flowable oxide layer, comprising the step of:

exposing the oxide layer to an oxygen plasma at a temperature of up to about 800°

C., and a time effective to eliminate a substantial amount of carbon from the oxide layer.

13. A method of treating a carbon-containing oxide layer disposed on a semiconductive substrate, comprising the step of:

depositing the oxide layer as a flowable oxide to fill a gap within the substrate; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

14. A method of treating an oxide layer disposed on a semiconductive substrate, comprising the steps of:

depositing an organosilane and an oxygen source gas by chemical vapor deposition onto the substrate to form a carbon-containing flowable oxide layer; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

15. A method of treating an oxide layer disposed on a semiconductive substrate, comprising the steps of:

depositing trimethylsilane and ozone by chemical vapor deposition to form a carbon-containing flowable oxide layer within a gap in the substrate; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

16. A method of treating a substrate, comprising the step of:

heating the substrate comprising a carbon-containing flowable oxide layer in a reaction chamber to a temperature of up to about 800°

C.;

maintaining a pressure within the reaction chamber at about 0.1 to about 20 torr; and

exposing the substrate to an oxygen plasma for a time effective to eliminate a substantial amount of carbon from the oxide layer.

17. The method of claim 16, wherein the step of exposing is conducted to reduce the amount of carbon in the oxide layer by at least about 80%.

18. The method of claim 16, further comprising:

forming the oxygen plasma in a downstream plasma system; and

flowing the oxygen plasma into the reaction chamber.

19. The method of claim 16, further comprising:

flowing an oxygen gas into the reaction chamber; and

forming the oxygen plasma within the chamber.

20. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

21. The method of claim 20, wherein the step of depositing comprises chemical vapor deposition of an organosilane and an oxygen source gas.

22. The method of claim 21, wherein the organosilane is selected from the group consisting of methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, diethylsilane, and Si_xC_yH_z where x is 1-2, y is 1-6, and z is 4-20.

23. The method of claim 21, wherein the oxygen source gas is selected from the group consisting of ozone, hydrogen peroxide vapor, nitrous oxide, and nitric oxide.

24. The method of claim 21, wherein the step of depositing comprises spin applying a flowable oxide material.

25. The method of claim 20, wherein the oxide layer is deposited to fill a gap in the substrate.

26. The method of claim 25, wherein the gap comprises an aspect ratio of about 7:

1 to about 10;

1.

27. The method of claim 25, wherein the oxide layer comprises a trench isolation area.

28. The method of claim 20, wherein the step of exposing comprises:

heating the substrate in a reaction chamber to a temperature of up to about 800°

C.

29. The method of claim 28, wherein the substrate is heated to a temperature of about 20 to about 450°

C.

30. The method of claim 28, wherein the substrate is heated to a temperature of about 50 to about 200°

C.

31. The method of claim 28, wherein the substrate is heated to a temperature of about 125°

C.

32. The method of claim 20, wherein the step of exposing comprises remotely forming the oxygen plasma and flowing the oxygen plasma into the reaction chamber.

33. The method of claim 20, wherein the step of exposing comprises flowing an oxygen gas into the reaction chamber, and forming the oxygen plasma within the chamber.

34. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

35. The method of claim 34, further comprising, prior to the exposing step, the step of heating the substrate to a temperature of up to about 800°

C.

36. The method of claim 34, wherein the depositing step comprises chemical vapor deposition of an organosilane and an oxygen source gas.

37. The method of claim 36, wherein the depositing step comprises chemical vapor deposition of trimethylsilane and ozone.

38. The method of claim 34, wherein the depositing step comprises spin applying a flowable oxide material.

39. The method of claim 34, wherein the oxide layer is deposited to fill a gap in the substrate.

40. The method of claim 39, wherein the gap comprises an aspect ratio of about 7:

1 to about 10;

1.

41. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate by chemical vapor deposition of trimethylsilane and ozone; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

42. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate;

heating the substrate to a temperature of up to about 20-450°

C.; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

43. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon to fill a gap in the substrate; and

exposing the oxide layer to an oxygen plasma to substantially eliminate carbon from the oxide layer.

44. The method of claim 43, wherein the gap has an aspect ratio of about 7:

1 to about 10;

1.

45. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate;

forming an oxygen plasma in a downstream plasma system;

flowing the oxygen plasma into the reaction chamber; and

exposing the oxide layer to the oxygen plasma to substantially eliminate carbon from the oxide layer.

46. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon on the substrate;

forming an oxygen plasma in the reaction chamber; and

exposing the oxide layer to the oxygen plasma to substantially eliminate carbon from the oxide layer.

47. A method of forming an oxide layer on a semiconductor substrate, comprising the steps of:

spin applying a layer of flowable oxide comprising carbon to fill a gap within the substrate disposed in a reaction chamber;

providing an oxygen plasma in the reaction chamber; and

exposing the oxide layer to the oxygen plasma to reduce the carbon content of the oxide layer to a non-detectable level.

48. The method of claim 47, wherein the carbon content is reduced by at least about 80%.

49. The method of claim 47, wherein the exposing step comprises exposing the oxide layer to the oxygen plasma for at least about 100 seconds at a substrate temperature of about 20 to about 450°

C.

50. A method of filling an opening in a substrate, comprising the steps of:

depositing a layer of flowable oxide to fill the opening; and

exposing the oxide to an oxygen plasma to substantially eliminate carbon from the oxide layer.

51. The method of claim 50, wherein the depositing step comprises chemical vapor deposition of an organosilane and an oxygen source gas.

52. The method of claim 50, wherein the depositing step comprises chemical vapor deposition of trimethylsilane and ozone.

53. The method of claim 50, wherein the depositing step comprises spin applying a flowable oxide material.

54. The method of claim 50, wherein the opening comprises an aspect ratio of about 7:

1 to about 10;

1.

55. The method of claim 50, wherein the opening comprises a trench.

56. The method of claim 50, wherein the carbon is reduced to a non-detectable level.

57. The method of claim 50, wherein the carbon is reduced by at least about 80%.

58. The method of claim 50, wherein the exposing step comprises exposing the oxide layer to the oxygen plasma for at least about 10 seconds at a substrate temperature of up to about 800°

C.

59. The method of claim 50, wherein the exposing step comprises exposing the oxide layer to the oxygen plasma for at least about 100 seconds at a substrate temperature of up to about 20 to about 450°

C.

60. A method of filling an opening in a substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon by chemical vapor deposition of trimethylsilane and ozone to fill the opening; and

exposing the oxide to an oxygen plasma for at least about 100 seconds at a substrate temperature of about 20 to about 450°

C. to reduce carbon in the oxide layer to at about 10% or less.

61. A method of filling an opening in a substrate, comprising the steps of:

depositing a layer of flowable oxide comprising carbon to partially fill the opening;

depositing a layer of high density plasma oxide to fill the opening; and

exposing the oxide layer to an oxygen plasma to reduce the carbon in the oxide layer by at least about 80%.

62. A method of filling a high aspect ratio opening in a substrate, the opening having an aspect ratio of about 7:

1 to about 10;

1, the method comprising the steps of;

depositing a layer of flowable oxide to fill the opening; and

exposing the oxide to an oxygen plasma for at least about 10 seconds at a substrate temperature of up to about 800°

C. to reduce carbon in the oxide layer by at least about 80%.

63. A method of filling a high aspect ratio opening in a substrate, the opening having an aspect ratio of about 7:

1 to about 10;

1, the method comprising the steps of;

depositing trimethylsilane and ozone by chemical vapor deposition to form a carbon-containing flowable oxide fill within the opening; and

exposing the oxide fill to an oxygen plasma for at least about 10 seconds at a substrate temperature of up to about 800°

C. to reduce residual carbon in the oxide fill by at least about 80%.

64. The method of claim 63, wherein the substrate is disposed within a reaction chamber, and the exposing step comprises flowing an oxygen source into a plasma within the reaction chamber.

65. The method of claim 63, wherein the substrate is disposed within a reaction chamber, and the exposing step comprises remotely forming the oxygen plasma and flowing the oxygen plasma into the reactor chamber.

66. An oxide fill disposed on a semiconductor substrate, and comprising a flowable oxide material treated with an oxygen plasma such that carbon in the oxide material is non-detectable.

67. An oxide fill disposed on a semiconductor substrate, and comprising an oxygen plasma treated flowable oxide material having a carbon content of less than about 10%.

68. An oxide fill disposed within an opening in a semiconductor substrate, and comprising an oxygen plasma treated flowable oxide material having substantially no voids and a carbon content of less than about 10%.

69. The oxide fill of claim 68, disposed within a deep trench in the semiconductor substrate.

70. An oxide fill disposed within an opening in a semiconductor substrate, the opening having an aspect ratio of about 7:

1 to about 10;

1;

the fill comprising an oxygen plasma treated flowable oxide material such that the fill comprises substantially no voids and a carbon content of less than about 10%.

71. An oxide fill disposed within an opening in a semiconductor substrate, and comprising an oxygen plasma treated flowable oxide material formed by chemical vapor deposition of an organosilane and an oxygen source gas, the fill having substantially no voids and a carbon content of less than about 10%.

72. An oxide fill disposed within an opening in a semiconductor substrate, and comprising an oxygen plasma treated flowable oxide material formed by chemical vapor deposition of an trimethylsilane and ozone, the fill having substantially no voids and a carbon content of less than about 10%.

73. An oxide fill disposed within an opening in a semiconductor substrate, and comprising an oxygen plasma treated flowable oxide material having substantially no voids and a carbon content of less than about 10%, the fill comprising a layer of a flowable oxide and an overlying layer of a high density plasma oxide.

74. A semiconductor device, comprising:

a substrate; and

an oxide material disposed on the substrate, the oxide material comprising an oxygen plasma treated flowable oxide formed by chemical vapor deposition of organosilane and an oxygen source gas, the oxide material having a carbon content of less than about 10%.

75. The device of claim 74, wherein the oxide material forms a trench isolation structure.

76. A semiconductor device, comprising:

a substrate; and

an oxygen plasma treated flowable oxide material disposed on the substrate, wherein carbon is non-detectable within the oxide material.

77. A semiconductor device, comprising:

a substrate; and

an oxygen plasma treated, flowable oxide material disposed on the substrate, the oxide material formed by chemical vapor deposition of an organosilane and an oxygen source gas, and comprising substantially no carbon.

78. A semiconductor device, comprising:

a substrate; and

an oxygen plasma treated, spin applied flowable oxide material disposed on the substrate, the oxide material comprising substantially no carbon.

79. A semiconductor device, comprising:

a substrate; and

an oxide fill disposed within an opening in the substrate, the fill comprising an oxygen plasma treated flowable oxide material formed by chemical vapor deposition of trimethylsilane and ozone, the fill having substantially no voids and substantially no carbon.

80. An integrated circuit supported by a substrate, and comprising:

an oxide layer disposed on the substrate, the oxide layer comprising an oxygen plasma treated flowable oxide and having a carbon content of less than about 10%.

81. An integrated circuit supported by a substrate, and comprising:

an oxide layer disposed on the substrate, the oxide layer comprising an oxygen plasma treated flowable oxide formed by chemical vapor deposition of an organosilane and an oxygen source gas, and having a carbon content of less than about 10%.

82. An integrated circuit supported by a substrate, and comprising:

an oxide layer disposed on the substrate, the oxide layer comprising an oxygen plasma treated flowable oxide formed by chemical vapor deposition of trimethylsilane and ozone, and having a carbon content of less than about 10%.

83. An integrated circuit supported by a substrate, and comprising:

an oxide layer disposed on the substrate, the oxide layer comprising an oxygen plasma treated, spin applied flowable oxide having a carbon content of less than about 10%.

84. An integrated circuit supported by a substrate, and comprising:

an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated flowable oxide and having a carbon content of less than about 10%.

85. The integrated circuit of claim 84, wherein the oxide fill is formed by chemical vapor deposition of an organosilane and an oxygen source gas.

86. The integrated circuit of claim 85, wherein the oxide fill is formed by chemical vapor deposition of trimethylsilane and ozone.

87. The integrated circuit of claim 84, wherein the oxide fill comprises a spin applied flowable oxide.

88. The integrated circuit of claim 84, wherein the oxide fill disposed in the opening comprises a trench isolation structure.

89. The integrated circuit of claim 84, wherein the opening has an aspect ratio of about 7:

1 to about 10;

1.

90. An electronic system, comprising:

a processor; and

an integrated circuit in communication with the processor, the integrated circuit comprising a substrate and an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated flowable oxide having a carbon content of less than about 10%.

91. The system of claim 90, wherein the integrated circuit is a memory circuit.

92. The system of claim 90, wherein the memory circuit is a DRAM memory circuit.

93. An electronic system, comprising:

a processor; and

an integrated circuit in communication with the processor, the integrated circuit comprising a substrate and an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated flowable oxide formed by chemical vapor deposition of an organosilane and an oxygen source gas, and having a carbon content of less than about 10%.

94. An electronic system, comprising:

a processor; and

an integrated circuit in communication with the processor, the integrated circuit comprising a substrate and an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated flowable oxide formed by chemical vapor deposition of trimethylsilane and ozone, and having a carbon content of less than about 10%.

95. An electronic system, comprising:

a processor; and

an integrated circuit in communication with the processor, the integrated circuit comprising a substrate and an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated flowable oxide having a carbon content of less than about 10%, the fill comprising a layer of a flowable oxide and an overlying layer of a high density plasma oxide.

96. An electronic system, comprising:

a processor; and

an integrated circuit in communication with the processor, the integrated circuit comprising a substrate and an oxide fill disposed in an opening in the substrate, the oxide fill comprising an oxygen plasma treated, spin applied flowable oxide having a carbon content of less than about 10%.