Method of depositing organosillicate layers

• US 6,531,398 B1
• Filed: 10/30/2000
• Issued: 03/11/2003
• Est. Priority Date: 10/30/2000
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Gaillard, Frederic, Nemani, Srinivas D., Yieh, Ellie, Fisher, Paul
• Primary Examiner(s): Powell, William A.
• Application Number:
  US09/702,600
• Time in Patent Office: 862 Days
• Field of Search: 438/692, 438/723, 438/743, 438/745, 438/756, 438/780, 438/781, 438/789, 427/489, 427/492, 427/497, 427/503, 427/509, 427/515, 427/577, 427/578, 427/579, 427/249.15, 427/255.37, 427/255.6
• US Class Current: 438/692
• CPC Class Codes: C23C 16/401 containing silicon
• 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 21/02208 the precursor containing a compound comprising Si
• 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/31612 on a silicon body
• CPC Class Codes: H01L 21/76801 characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
• CPC Class Codes: H01L 21/7681 involving one or more buried masks
• CPC Class Codes: H01L 21/76828 thermal treatment
• CPC Class Codes: H01L 21/76835 Combinations of two or more different dielectric layers having a low dielectric constant H01L21/76832 takes precedence

Abstract

A method of forming an organosilicate layer is disclosed. The organosilicate layer is formed by applying an electric field to a gas mixture comprising an organosilane compound and an oxygen-containing gas. The organosilicate layer is compatible with integrated circuit fabrication processes. In one integrated circuit fabrication process, the organosilicate layer is used as an intermetal dielectric layer. In another integrated circuit fabrication process, the organosilicate layer is incorporated into a damascene structure.

Claims

1. A method of thin film deposition, comprising:

positioning a substrate in a deposition chamber;

providing a gas mixture to the deposition chamber, wherein the gas mixture comprises an organosilane compound and an oxygen-containing gas; and

applying an electric field to the gas mixture in the deposition chamber to form an organosilicate layer on the substrate.

2. The method of claim 1 wherein the organosilane compound has a general formula Si_aC_bH_cO_d where a has a range between 1 and 2, b has a range between 1 and 10, c has a range between 6 and 30, and d has a range between 0 and 6.

3. The method of claim 2 wherein the organosilane compound is selected from the group of methylsilane (SiCH₆), dimethylsilane (SiC₂H₈), trimethylsilane (SiC₃H₁₀), tetramethylsilane (SiC₄H₁₂), methoxysilane (SiCH₆O), dimethyldimethoxysilane (SiC₄H₁₂O₂), diethyldiethoxysilane (SiC₈H₁₈O₂), dimethyldiethoxysilane (SiC₆H₁₆O₂), diethyldimethoxysilane (SiC₆H₁₆O₂), hexamethyldisiloxane (Si₂C₆H₁₈O), bis(methylsilano)methane (Si₂C₃H₁₂), 1,2-bis (methylsilano) ethane (Si₂C₄H₁₄), and combinations thereof.

4. The method of claim 1 wherein the oxygen-containing gas is selected from the group of nitrous oxide (N₂O), oxygen (O₂), ozone (O₃) carbon monoxide (CO), carbon dioxide (CO₂), and combinations thereof.

5. The method of claim 1 wherein the electric field applied to the gas mixture in the deposition chamber is a radio frequency (RF) power.

6. The method of claim 5 wherein the RF power is within the range of about 1 watts/cm² to about 500 watts/cm².

7. The method of claim 1 wherein the deposition chamber is maintained at a pressure between about 1 torr to about 500 torr.

8. The method of claim 1 wherein the organosilane compound is provided to the deposition chamber at a flow rate in a range of about 50 sccm to about 1000 sccm.

9. The method of claim 1 wherein the oxygen-containing gas is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 1000 sccm.

10. The method of claim 1 wherein the ratio of the oxygen-containing gas to the organosilane compound is about 1:

1 to about 1;

5.

11. The method of claim 1 wherein the deposition chamber is maintained at a temperature between about 50°

C. to about 500°

C.

12. The method of claim 1 wherein the organosilicate layer is formed on the substrate at a rate greater than about 0.1 microns per minute.

13. The method of claim 1 further comprising the step of annealing the organosilicate layer formed on the substrate.

14. The method of claim 13 wherein the annealing step is performed at a temperature between about 200°

C. to about 500°

C.

15. The method of claim 13 wherein the annealing step is performed in an atmosphere comprising one or more gases selected from the group of nitrogen (N₂), hydrogen (H₂), and oxygen (O₂).

16. The method of claim 13 wherein the annealing step is performed for a time less than about 30 minutes.

17. A method forming an organosilicate layer on a substrate, comprising:

positioning a substrate in a deposition chamber;

providing a gas mixture to the deposition chamber, wherein the gas mixture comprises an organosilane compound and an oxygen-containing gas; and

applying an electric field to the gas mixture in the deposition chamber to form an organosilicate layer on the substrate.

18. The method of claim 17 wherein the organosilane compound has a general formula Si_aC_bH_cO_d where a has a range between 1 and 2, b has a range between 1 and 10, c has a range between 6 and 30, and d has a range between 0 and 6.

19. The method of claim 18 wherein the organosilane compound is selected from the group of methylsilane (SiCH₆), dimethylsilane (SiC₂H₈), trimethylsilane (SiC₃H₁₀), tetramethylsilane (SiC₄H₁₂), methoxysilane (SiCH₆O), dimethyldimethoxysilane (SiC₄H₁₂O₂), diethyldiethoxysilane (SiC₈H₁₈O₂), dimethyldiethoxysilane (SiC₆H₁₆O₂), diethyldimethoxysilane (SiC₆H₁₆O₂), hexamethyldisiloxane (Si₂C₆H₁₈O), bis(methylsilano)methane (Si₂C₃H₁₂), 1,2-bis(methylsilano)ethane (Si₂C₄H₁₄), and combinations thereof.

20. The method of claim 17 wherein the oxygen-containing gas is selected from the group of nitrous oxide (N₂O), oxygen (O₂), ozone (O₃), carbon monoxide (CO), carbon dioxide (CO₂), and combinations thereof.

21. The method of claim 17 wherein the electric field applied to the gas mixture in the deposition chamber is a radio frequency (RF) power.

22. The method of claim 21 wherein the RF power is within the range of about 1 watts/cm² to about 500 watts/cm².

23. The method of claim 17 wherein the deposition chamber is maintained at a pressure between about 1 torr to about 500 torr.

24. The method of claim 17 wherein the organosilane compound is provided to the deposition chamber at a flow rate in a range of about 50 sccm to about 1000 sccm.

25. The method of claim 17 wherein the oxygen-containing gas is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 1000 sccm.

26. The method of claim 17 wherein the ratio of the oxygen-containing gas to the organosilane compound is about 1:

1 to about 1;

5.

27. The method of claim 17 wherein the deposition chamber is maintained at a temperature between about 50°

C. to about 500°

C.

28. The method of claim 17 wherein the organosilicate layer is formed on the substrate at a rate greater than about 0.1 microns per minute.

29. The method of claim 17 further comprising the step of annealing the organosilicate layer formed on the substrate.

30. The method of claim 29 wherein the annealing step is performed at a temperature between about 200°

C. to about 500°

C.

31. The method of claim 29 wherein the annealing step is performed in an atmosphere comprising one or more gases selected from the group of nitrogen (N₂), hydrogen (H₂), and oxygen (O₂).

32. The method of claim 29 wherein the annealing step is performed for a time less than about 30 minutes.

33. A computer storage medium containing a software routine that, when executed, causes a general purpose computer to control a deposition chamber using a layer deposition method, comprising:

positioning a substrate in a deposition chamber;

providing a gas mixture to the deposition chamber, wherein the gas mixture comprises an organosilane compound and an oxygen-containing gas; and

applying an electric field to the gas mixture in the deposition chamber to form an organosilicate layer on the substrate.

34. The computer storage medium of claim 33 wherein the organosilane compound has a general formula Si_aC_bH_cO_d where a has a range between 1 and 2, b has a range between 1 and 10, c has a range between 6 and 30, and d has a range between 0 and 6.

35. The computer storage medium of claim 34 wherein the organosilane compound is selected from the group of methylsilane (SiCH₆), dimethylsilane (SiC₂H₈), trimethylsilane (SiC₃H₁₀), tetramethylsilane (SiC₄H₁₂), methoxysilane (SiCH₆O), dimethyldimethoxysilane (SiC₄H₁₂O₂), diethyldiethoxysilane (SiC₈H₁₈O₂), dimethyldiethoxysilane (SiC₆H₁₆O₂), diethyldimethoxysilane (SiC₆H₁₆O₂), hexamethyldisiloxane (Si₂C₆H₁₈O), bis(methylsilano)methane (Si₂C₃H₁₂), 1,2-bis(methylsilano)ethane (Si₂C₄H₁₄), and combinations thereof.

36. The computer storage medium of claim 33 wherein the oxygen-containing gas is selected from the group of nitrous oxide (N₂O), oxygen (O₂), ozone (O₃), carbon monoxide (CO), carbon dioxide (CO₂), and combinations thereof.

37. The computer storage medium of claim 33 wherein the electric field applied to the gas mixture in the deposition chamber is a radio frequency (RF) power.

38. The computer storage medium of claim 37 wherein the RF power is within the range of about 1 watts/cm² to about 500 watts/cm².

39. The computer storage medium of claim 33 wherein the deposition chamber is maintained at a pressure between about 1 torr to about 500 torr.

40. The computer storage medium of claim 33 wherein the organosilane compound is provided to the deposition chamber at a flow rate in a range of about 50 sccm to about 1000 sccm.

41. The computer storage medium of claim 33 wherein the oxygen-containing gas is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 1000 sccm.

42. The computer storage medium of claim 33 wherein the ratio of the oxygen-containing gas to the organosilane compound is about 1:

1 to about 1;

5.

43. The computer storage medium of claim 33 wherein the deposition chamber is maintained at a temperature between about 50°

C. to about 500°

C.

44. The computer storage medium of claim 33 wherein the organosilicate layer is formed on the substrate at a rate greater than a bout 0.1 microns per minute.

45. The computer storage medium of claim 33 further comprising the step of annealing the organosilicate layer formed on the substrate.

46. The computer storage medium of claim 45 wherein the annealing step is performed at a temperature between about 200°

C. to about 500°

C.

47. The computer storage medium of claim 45 wherein the annealing step is performed in an atmosphere comprising one or more gases selected from the group of nitrogen (N₂), hydrogen (H₂), and oxygen (O₂).

48. The computer storage medium of claim 45 wherein the annealing step is performed a time for less than about 30 minutes.

49. A method of forming a device, comprising:

providing a substrate having conductive features formed thereon; and

forming an organosilicate layer over the conductive features, wherein the organosilicate layer is formed by applying an electric field to a gas mixture comprising an organosilane compound and an oxygen-containing gas.

50. The method of claim 49 wherein the conductive features are formed of one or more materials selected from the group consisting of copper, aluminum, tungsten, and combinations thereof.

51. The method of claim 49 wherein the organosilane compound has a general formula Si_aC_bH_cO_d where a has a range between 1 and 2, b has a range between 1 and 10, c has a range between 6 and 30, and d has a range between 0 and 6.

52. The method of claim 51 wherein the organosilane compound is selected from the group of methylsilane (SiCH₆), dimethylsilane (SiC₂H₈), trimethylsilane (SiC₃H₁₀) tetramethylsilane (SiC₄H₁₂), methoxysilane (SiCH₆O), dimethyldimethoxysilane (SiC₄H₁₂O₂), diethyldiethoxysilane (SiC₈H₁₈O₂), dimethyldiethoxysilane (SiC₆H₁₆O₂), diethyldimethoxysilane (SiC₆H₁₆O₂), hexamethyldisiloxane (Si₂C₆H₁₈O), bis(methylsilano)methane (Si₂C₃H₁₂), 1,2-bis(methylsilano) ethane (Si₂C₄H₁₄), and combinations thereof.

53. The method of claim 49 wherein the oxygen-containing gas is selected from the group of nitrous oxide (N₂O), oxygen (O₂), ozone (O₃), carbon monoxide (CO), carbon dioxide (CO₂), and combinations thereof.

54. The method of claim 49 wherein the electric field applied to the gas mixture is a radio frequency (RF) power.

55. The method of claim 54 wherein the RF power is within the range of about 1 watts/cm² to about 500 watts/cm².

56. The method of claim 49 wherein the organosilicate layer is formed in a deposition chamber maintained at a pressure between about 1 torr to about 500 torr.

57. The method of claim 56 wherein the organosilane compound is provided to the deposition chamber at a flow rate in a range of about 50 sccm to about 1000 sccm.

58. The method of claim 56 wherein the oxygen-containing gas is provided to the deposition chamber at a flow rate in a range of about 10 sccm to about 1000 sccm.

59. The method of claim 56 wherein the ratio of the oxygen-containing gas to the organosilane compound is about 1:

1 to about 1;

5.

60. The method of claim 56 wherein the deposition chamber is maintained at a temperature between about 50°

C. to about 500°

C.

61. The method of claim 49 wherein the organosilicate layer is formed over the conductive features at a rate greater than about 0.1 microns per minute.

62. The method of claim 49 further comprising the step of annealing the organosilicate layer formed on the substrate.

63. The method of claim 62 wherein the annealing step is performed at a temperature between about 200°

C. to about 500°

C.

64. The method of claim 62 wherein the annealing step is performed in an atmosphere comprising one or more gases selected from the group of nitrogen (N₂), hydrogen (H₂), and oxygen (O₂).

65. The method of claim 63 wherein the annealing step is performed for a time less than about 30 minutes.

66. A method of fabricating a damascene structure, comprising

forming a first dielectric layer on a substrate;

forming an organosilicate layer on the first dielectric layer, wherein the organosilicate layer is formed by applying an electric field to a gas mixture comprising an organosilane compound and an oxygen-containing gas;

patterning the organosilicate layer to define contacts/vias therethrough;

forming a second dielectric layer on the patterned organosilicate layer;

patterning the second dielectric layer to define interconnects therethrough, wherein the interconnects are positioned over the contacts/vias defined in the organosilicate layer;

etching the first dielectric layer to form contacts/vias therethrough; and

filling the contacts/vias and the interconnects with a conductive material.

67. The method of claim 66 wherein the first dielectric layer and the second dielectric layer are each selected from the group consisting of amorphous carbon, fluorinated amorphous carbon, parylene, fluorinated silicate glass (FSG), AF₄, BCB, silicon carbide, oxynitride, and combinations thereof.

68. The method of claim 66 wherein the conductive material filling the contacts/vias and interconnects is selected from the group consisting of copper, aluminum, tungsten, and combinations thereof.

69. The method of claim 66 wherein the organosilane compound has a general formula Si_aC_bH_cO_d where a has a range between 1 and 2, b has a range between 1 and 10, c has a range between 6 and 30, and d has a range between 0 and 6.

70. The method of claim 69 wherein the organosilane compound is selected from the group of methylsilane (SiCH₆), dimethylsilane (SiC₂H₈), trimethylsilane (SiC₃H₁₀), tetramethylsilane (SiC₄H₁₂), methoxysilane (SiCH₆O), dimethyldimethoxysilane (SiC₄H₁₂O₂), diethyldiethoxysilane (SiC₈H₁₈O₂), dimethyldiethoxysilane (SiC₆H₁₆O₂), diethyldimethoxysilane (SiC₆H₁₆O₂), hexamethyldisiloxane (Si₂C₆H₁₈O), bis(methylsilano)methane (Si₂C₃H₁₂), 1,2-bis(methylsilano)ethane (Si₂C₄H₁₄), and combinations thereof.

71. The method of claim 66 wherein the oxygen-containing gas is selected from the group of nitrous oxide (N₂O), oxygen (O₂), ozone (O₃), carbon monoxide (CO), carbon dioxide (CO₂), and combinations thereof.

72. The method of claim 66 wherein the electric field applied to the gas mixture is a radio frequency (RF) power.

73. The method of claim 72 wherein the RF power is within the range of about 1 watts/cm² to about 500 watts/cm².

74. The method of claim 66 wherein the organosilicate layer is formed in a deposition chamber maintained at a pressure between about 1 torr to about 500 torr.

75. The method of claim 74 wherein the organosilane compound is provided to the deposition chamber at a flow rate in a range of about 50 sccm to about 1000 sccm.

76. The method of claim 74 wherein the oxygen-containing gas is provided to the deposition chamber at a flow rate in a range of about 10 scam to about 1000 sccm.

77. The method of claim 74 wherein the ratio of the oxygen-containing gas to the organosilane component is about 1:

1 to about 1;

5.

78. The method of claim 74 wherein the deposition chamber is maintained at a temperature between about 50°

C. to about 500°

C.

79. The method of claim 66 wherein the organosilicate layer is formed on the first dielectric layer at a rate greater than about 0.1 microns per minute.

80. The method of claim 66 further comprising the step of annealing the organosilicate layer formed on the first dielectric layer.

81. The method of claim 80 wherein the annealing step is performed at a temperature between about 200°

C. to about 500°

C.

82. The method of claim 80 wherein the annealing step is performed in an atmosphere comprising one or more gases selected from the group of nitrogen (N₂), hydrogen (H₂), and oxygen (O₂).

83. The method of claim 80 wherein the annealing step is