Sequential pulse deposition

• US 20020110991A1
• Filed: 02/13/2001
• Published: 08/15/2002
• Est. Priority Date: 02/13/2001
• Status: Active Grant

• Current Assignee: Conversant Intellectual Property Management Inc (MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management))
• Original Assignee: Micron Technology, Inc.
• Inventors: Li, Weimin
• Granted Patent: US 6,613,656 B2
• Time in Patent Office: Days
• US Class Current: 438/347
• CPC Class Codes: C23C 16/4408 by purging residual gases from the reaction chamber or gas lines
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: H01L 21/28506 of conductive layers

Abstract

A method for growing films on substrates using sequentially pulsed precursors and reactants, system and devices for performing the method, semiconductor devices so produced, and machine readable media containing the method.

Claims

1. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber; and

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber.

2. The method according to claim 1, wherein the precursor gas is near the surface of the substrate before the reactant gas flows into the reaction chamber.

3. The method according to claim 1, further comprising flowing an inert purge gas into the chamber in between flowing the precursor gas and the reactant gas.

4. The method according to claim 1, wherein the process steps are performed in the listed order.

5. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

reacting the precursor gas with the reaction gas adjacent the substrate to deposit a layer of the film on the substrate; and

wherein flowing the reactant gas into the chamber occurs after stopping the flow of the precursor gas.

6. The method according to claim 5, wherein, if necessary, the above process is repeated until the film has a desired thickness;

and flowing precursor gas into the chamber occurs after stopping precursor gas flow into the chamber while repeating the steps.

7. The method according to claim 6, wherein flowing the precursor gas and flowing the reactant gas are performed without completely purging the remaining reactant gas and the precursor gas from the preceding steps.

8. The method according to claim 5, wherein reacting the precursor with the reactant forms a layer on the substrate at a rate greater than 100 Å

/cycle.

9. The method according to claim 5, wherein the steps are performed in the listed order.

10. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber; and

flowing an inert purge gas into the chamber in between flowing the precursor gas and the reactant gas.

11. The method according to claim 10, wherein the purge gas flows while flowing the precursor gas and the reactant gas.

12. The method according to claim 10, wherein flowing the purge gas maintains an essentially constant chamber pressure.

14. The method according to claim 13, wherein, if necessary, the above process is repeated until the film has a desired thickness, flowing N₂O gas into the chamber occurs after stopping Pt and Rh precursor gas flows into the chamber while repeating the process, and flowing the Pt and Rh precursor gases and flowing the N₂O gas are performed without completely purging the remaining N₂O gas and the Pt and Rh precursor gases from the preceding process.

15. The method according to claim 13, further comprising flowing an inert purge gas into the chamber in between flowing the Pt and Rh precursor gases and the N₂O gas.

17. The method according to claim 16, wherein CVD chemistry occurs near the surface of the substrate to deposit the film on the substrate and reduce gas phase interaction of the precursor and the reactant.

18. The method according to claim 16, wherein flowing the precursor gas and flowing the reactant gas are performed without completely purging the remaining reactant gas and the precursor gas from the preceding flowing steps.

19. The method according to claim 16, wherein flowing the precursor gas uniformly covers the steps in the substrate such that precursor material is adjacent essentially the entire surface of the step.

13. A method of forming a film on a substrate, comprising:

flowing a PT and Rh precursor gases into a reaction chamber containing the substrate;

flowing a N₂O gas into the reaction chamber; and

wherein the Pt and Rh precursor gases and the N₂O gas are sequentially pulsed into the chamber.

16. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber; and

wherein flowing precursor gas includes saturating precursor near the surface of the substrate so that steps in the substrate are generally covered by precursor.

20. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

heating the chamber to facilitate the chemical reaction of the precursor and the reactant to deposit a film on the substrate; and

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber.

21. The method according to claim 20, wherein heating the chamber includes heating the chamber to at least 100 degrees (C.).

22. The method according to claim 20, wherein heating the chamber includes heating the chamber to at least 200 degrees (C.).

23. The method according to claim 20, wherein heating the chamber includes heating the chamber to at least 300 degrees (C.).

24. The method according to claim 21, wherein the precursor and the reactant react to grow a film a rate of at least 10 Å

/cycle.

27. The method according to claim 26, wherein the precursor gas is predominately near the surface of the substrate before the reactant gas flows into the reaction chamber.

28. The method according to claim 26, further comprising flowing an inert purge gas into the chamber while flowing the precursor gas and the reactant gas.

29. The method according to claim 26, wherein the process steps are performed in the listed order.

25. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

wherein flowing the precursor gas and the reactant gas includes sequentially pulsing the precursor gas and the reactant gas into the chamber; and

wherein the precursor includes a source of at least one of a metal selected from the group consisting of rhenium, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold.

26. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

stopping flow of precursor gas;

flowing a reactant gas into the reaction chamber; and

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas.

30. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

stopping flow of the precursor gas;

flowing a reactant gas into the reaction chamber;

reacting the precursor gas with the reaction gas adjacent the substrate to deposit a layer of the film on the substrate; and

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas.

31. The method according to claim 30, wherein, if necessary to grow the film to a desired thickness, the above process steps are repeated, and flowing precursor gas into the chamber occurs simultaneously with stopping reactant gas flow when repeating the process steps.

32. The method according to claim 30, wherein purge gas flows while flowing the precursor gas and the reactant gas.

33. The method according to claim 30, wherein the precursor gas contains Pt and Rh precursors and the reactant gas contains N₂O.

34. The method according to claim 30, wherein flowing precursor gas includes saturating the precursor near the surface of the substrate so that steps in the substrate are covered by precursor.

35. The method according to claim 34, wherein saturating the precursor near the surface of the substrate includes CVD chemistry occurring predominately near the surface of the substrate to deposit the layer on the substrate in order to reduce gas phase interaction of the precursor and the reactant.

37. The method according to claim 36, wherein flowing the purge gas maintains an essentially constant chamber pressure.

39. The method according to claim 38, wherein the reactant gas is one of N₂O, O₂, and H₂.

40. The method according to claim 38, wherein, if necessary, the above process is repeated until the film has a desired thickness, flowing Pt and Rh gases into the chamber occurs after stopping reactant gas flow into the chamber while repeating the process.

41. The method according to claim 38, further comprising flowing an inert purge gas into the chamber while flowing the Pt and Rh gases and the reactant gas.

36. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas; and

flowing an inert purge gas into the chamber while flowing at least one of the precursor gas and the reactant gas.

38. A method of forming a film on a substrate, comprising:

flowing Pt and Rh gases into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber; and

wherein flowing the reactant gas occurs essentially simultaneously with stopping the flow of the Pt and Rh gases.

42. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

stopping flow of the precursor gas;

flowing a reactant gas into the reaction chamber;

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas; and

wherein flowing precursor gas includes saturating precursor near the surface of the substrate so that steps in the substrate are generally covered by precursor.

43. The method according to claim 42, wherein saturating the precursor near the surface of the substrate includes CVD chemistry occurring predominately near the surface of the substrate to deposit the film on the substrate and reduce gas phase interaction of the precursor and the reactant.

44. The method according to claim 43, wherein the above steps are repeated, and flowing the precursor gas and flowing the reactant gas are performed without completely purging the remaining reactant gas and the precursor gas from the preceding flowing steps.

46. The method according to claim 45, wherein the chamber is heated to at least 300 degrees (C).

47. The method according to claim 46, wherein the precursor and the reactant react to grow a film a rate of at least 5 Å

/cycle.

45. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

heating the chamber to facilitate the chemical reaction of the precursor and the reactant to deposit a film on the substrate; and

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas.

48. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

stopping flow of the precursor gas;

flowing a reactant gas into the reaction chamber;

wherein flowing the reactant gas into the chamber occurs essentially simultaneously with stopping the flow of the precursor gas; and

wherein the precursor includes at least one of a metal selected from the group consisting of rhenium, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold.

49. A method of forming a metal or dielectric film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate so that the precursor gas is adjacent the substrate, the precursor gas containing one of a metal and a dielectric to be deposited on the substrate;

flowing a reactant gas into the reaction chamber;

reacting the precursor gas with the reaction gas adjacent the substrate to deposit multiple atomic layers of the film during each reacting step;

repeating the above steps until the film has a desired thickness; and

the flowing of the reactant gas into the chamber occurs after stopping the flow of the precursor gas.

50. A semiconductor device, comprising:

a substrate; and

a first layer deposited on the substrate, wherein the first layer is deposited by sequentially pulsing a precursor gas and a reactant into a reaction chamber, and wherein the precursor gas and reactant react to deposit the first layer on the substrate.

51. The semiconductor device according to claim 50, wherein a second layer is deposited on the first layer, wherein the second layer of the film is deposited by sequentially pulsing a precursor gas and a reactant into the reaction chamber, and wherein the precursor gas and reactant react to deposit the second layer on the substrate.

52. The semiconductor device according to claim 51, wherein the first and second layers are made of the same material.

53. The semiconductor device according to claim 52, wherein the first and second layers are a metal.

54. The semiconductor device according to claim 53, wherein the first and second metal layers include at least one of rhenium, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold.

55. A memory device in an integrated circuit, comprising:

a substrate; and

a first layer deposited on the substrate, wherein the first layer is essentially devoid of contaminants, the first layer is deposited by sequentially pulsing a precursor gas and a reactant into a reaction chamber, and wherein the precursor gas and reactant react predominately adjacent the substrate to deposit the first layer on the substrate, the first layer being part of the memory device.

56. The memory device according to claim 55, wherein the first layer is one of a gate, source and drain of a transistor in the memory device.

58. The logic device according to claim 57, wherein the first layer is one of a gate, source, and drain in a transistor in the logic device.

60. The semiconductor device according to claim 59, wherein the first and second layers are the same material.

61. The semiconductor device according to claim 59, wherein the first and second layers include a metal.

62. The semiconductor device according to claim 59, wherein the pulse the precursor gas and the pulse of the reactant gas are separated by a time period, wherein the time period allows the precursor gas to settle adjacent the surface of the substrate.

57. A logic device in an integrated circuit, comprising:

a substrate; and

a first layer deposited on the substrate, wherein the first layer is essentially devoid of contaminants, the first layer is deposited by sequentially pulsing a precursor gas and a reactant into a reaction chamber, and wherein the precursor gas and reactant react predominately adjacent the substrate to deposit the first layer on the substrate, the first layer being part of a logic device.

59. A semiconductor device, comprising:

a substrate;

a first layer of a film deposited on the substrate, wherein the first layer is deposited by injecting a pulse of precursor gas into a chamber containing the substrate and injecting a pulse of reactant gas into the chamber, wherein the precursor and the reactant react to deposit the first layer on the substrate; and

a second layer of the film deposited on the first layer of the film, wherein the second layer is deposited by injecting a pulse of precursor gas into a chamber containing the substrate and injecting a pulse of reactant gas into the chamber, wherein the precursor and the reactant react to deposit the second layer on the first layer, and still further wherein the pulses of precursor gas and reactant gas are separate.

63. A deposition device for forming films on substrates, comprising:

a reaction chamber;

a source of precursor gas;

a source of reactant gas;

a mount for a substrate in the chamber; and

a controller for sequentially pulsing the precursor gas and the reactant gas into the chamber, the precursor gas being first pulsed into the chamber so that the precursor gas is adjacent a surface of the substrate, the reactant gas being pulsed into the chamber to react with the precursor gas to deposit a film on the surface of the substrate.

64. The deposition device according to claim 63, wherein the controller discretely pulses the precursor gas and the reactant gas into the chamber.

65. A machine readable medium having instructions stored thereon, comprising:

first instructions for causing a chemical vapor deposition reactor to initiate depositing a film on a substrate by injecting a pulse of precursor gas into a reaction chamber; and

second instructions for causing the reactor to inject a pulse of reactant gas into the reaction chamber after the pulse of precursor gas has been injected into the reaction chamber.

66. The machine readable medium according to claim 65, further comprising third instructions for causing the reactor to continue sequentially injecting pulses of precursor gas and reactant gas until the deposited film has a select thickness.

67. The machine readable medium according to claim 65, wherein the first instructions for causing a chemical vapor deposition reactor to initiate depositing a film further comprise instructions for ending the pulse of precursor gas prior to proceeding to the second instructions.

68. The machine readable medium according to claim 66, wherein the second instructions include a delay during which neither the precursor gas nor the reactant gas are injected into the reaction chamber.

69. The machine readable medium according to claim 65, further comprising third instructions for holding the chamber at a constant pressure.

70. The machine readable medium according to claim 65, wherein the first instructions cause the chemical vapor deposition reactor to inject a precursor gas having a metal constituent that will be deposited on the substrate.

71. The machine readable medium according to claim 65, further comprising third instructions for heating the reaction chamber above 300 degrees C.

72. A chemical vapor deposition system, comprising:

a chemical vapor deposition reactor;

a control system in communication with the reactor; and

a machine readable medium in communication with the control system, wherein the machine readable medium has;

first instructions for causing the chemical vapor deposition reactor to initiate depositing a film on a substrate by injecting a pulse of precursor gas into a reaction chamber, and

second instructions for causing the reactor to inject a pulse of reactant gas into the reaction chamber after the pulse of precursor gas is injected into the reaction chamber.

73. The chemical vapor deposition system according to claim 72, further comprising third instructions for causing the reactor to continue sequentially injecting pulses of precursor gas and reactant gas until the deposited film has a select thickness.

74. The chemical vapor deposition system according to claim 73, wherein the third instructions include instructions to delay injection of pulses of precursor gas until after the pulse of reactant gas ends.

75. The chemical vapor deposition system according to claim 74, wherein the first instructions include instructions to delay injection of pulses of precursor gas until after a time delay elapses after the end of the pulse of reactant gas.

76. The chemical vapor deposition system according to claim 73, wherein the second instructions include instructions to delay injection of pulses of reactant gas until after a time delay elapses after the end of the pulse of precursor gas.

77. The chemical vapor deposition system according to claim 73, wherein the control system is physically associated with the reactor.

78. The chemical vapor deposition system according to claim 77, wherein the machine readable medium is physically associated with the control system.

79. The chemical vapor deposition system according to claim 73, wherein the first instructions cause the reactor to inject a precursor gas having a metal constituent to be deposited on the substrate.

80. The chemical vapor deposition system according to claim 73, wherein the machine readable medium includes fourth instructions to heat the reactor to at least 300 degrees C.

81. The chemical vapor deposition system according to claim 73, wherein the machine readable medium includes fourth instructions to maintain a generally constant pressure in a chamber of the reaction chamber.

82. The chemical vapor deposition system according to claim 73, wherein the control system injects precursor and reactant gases to grow more than one atomic layer of the film for each pulse of precursor gas.

83. A reactor for forming films on substrates, comprising:

a reaction chamber;

a first gas source connected to the reaction chamber;

a second gas source connected to the reaction chamber;

a mount for a substrate in the reaction chamber; and

a controller sequentially activating the first gas source and the second gas source such that the first gas is in the reaction chamber adjacent the substrate prior to injecting the second gas into the reaction chamber to form a film on the substrate based on the reaction of the first and second gases in the reaction chamber.

84. A method of forming a film on a substrate, comprising:

flowing a reactant gas into the reaction chamber;

thereafter flowing a precursor gas into a reaction chamber containing the substrate; and

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber.

85. A method of forming a film on a substrate, comprising:

flowing a precursor gas into a reaction chamber containing the substrate;

flowing a reactant gas into the reaction chamber;

wherein the precursor gas and the reactant gas are sequentially pulsed into the chamber; and

wherein the amount of at least one of the precursor gas and the reactant gas exceeds the amount required to form the film on the substrate.

86. The method according to claim 85, wherein flowing the precursor gas includes reacting the precursor and reactant gases together to form the film, and thereafter flowing byproduct gas from the reaction chamber.

87. The method according to claim 86, wherein flowing the byproduct gases includes flowing the excess one of the precursor gas and the reactant gas from the reaction chamber.

88. The method according to claim 86, wherein flowing the precursor, flowing the reactant, and flowing the byproduct gas together include growing the film at a rate greater than about 5 Å

per each cycle of flowing the precursor, flowing the reactant, and flowing the byproduct gas.

89. The method according to claim 88, wherein growing the film includes growing the film at a rate of about 100 Å

per each cycle.

90. The method according to claim 85, wherein flowing the precursor gas into a reaction chamber containing the substrate includes flowing a precursor gas containing a metal component into the reaction chamber.