Chemical-mechanical planarization slurries and powders and methods for using same

1. A method for making a slurry with abrasive particles for use in chemical-mechanical planarization, the method comprising:

generating an aerosol stream, as generated the aerosol stream comprising droplets comprising a precursor for abrasive particles;

forming the abrasive particles in the aerosol stream, the abrasive particles having a weight average particle size of not greater than 3 microns;

the forming comprising heating the aerosol stream;

after the forming, making a chemical-mechanical planarization slurry incorporating the abrasive particles.

2. The method of claim 1 , wherein the abrasive particles are in single crystalline form.

3. The method of claim 1 , wherein the abrasive particles are in polycrystalline form.

4. The method of claim 1 , wherein the precursor is for and the abrasive particles comprise CeO 2 .

5. The method of claim 1 , wherein the precursor is for and the abrasive particles comprise Al 2 O 3 .

6. The method of claim 1 , wherein the precursor is for and the abrasive particles comprise SiO 2 .

7. The method of claim 1 , wherein the precursor is for and the abrasive particles comprise ZrO 2 .

8. The method of claim 1 , wherein the precursor is for and the abrasive particles comprise a member selected from the group consisting of TiO 2 , MgO, HfO 2 , MnO 2 , V 2 O 5 , SnO 2 , ZnO, Fe 2 O 3 , Fe 3 O 4 and Cr 2 O 3 .

9. The method of claim 1 , wherein the abrasive particles are composite particles.

10. The method of claim 9 , wherein the composite particles comprise an abrasive phase and a second phase dispersed throughout the abrasive phase.

11. The method of claim 9 , wherein the composite particles comprise SiO 2 and Al 2 O 3 .

12. The method of claim 9 , wherein the composite particles comprise SiO 2 and CeO 2 .

13. The method of claim 9 , wherein the composite particles comprise Al 2 O 3 and CeO 2 .

14. The method of claim 9 , wherein the composite particles comprise MnO 2 and Mn 3 O 4 .

15. The method of claim 9 , wherein the composite particles comprise at least 1 weight percent of the second phase.

16. The method of claim 15 , wherein the composite particles comprise from 2 weight percent to 50 weight percent of the second phase.

17. The method of claim 15 , wherein the composite particles comprise from 5 weight percent to 35 weight percent of the second phase.

18. The method of claim 1 , wherein the abrasive particles comprise a complex oxide.

19. The method of claim 1 , wherein the abrasive particles have a weight average particle size of not greater than 2 microns.

20. The method of claim 1 , wherein the abrasive particles have a weight average particle size of not greater than 1 micron.

21. The method of claim 20 , wherein the abrasive particles have a weight average particle size of at least 0.05 micron.

22. The method of claim 20 , wherein at least 90 weight percent of the abrasive particles are not larger than twice the weight average particle size.

23. The method of claim 1 , wherein the abrasive particles have an average crystallite size of at least 10 nanometers.

24. The method of claim 1 , wherein the abrasive particles have an average crystallite size of at least 20 nanometers.

25. The method of claim 1 , wherein the abrasive particles comprise no more than 0.1 atomic percent impurities.

26. The method of claim 1 , wherein the abrasive particles comprise no more than 0.01 atomic percent impurities.

27. The method of claim 1 , wherein the abrasive particles are substantially unagglomerated.

28. The method of claim 1 , wherein in the droplets, the precursor is dissolved in a liquid.

29. The method of claim 28 , wherein the precursor is a first precursor and the droplets comprise at least a second precursor.

30. The method of claim 29 , wherein in the droplets, the second precursor is dissolved in the liquid.

31. The method of claim 29 , wherein in the droplets, the second precursor is in the form of colloidal particles.

32. The method of claim 31 , wherein the colloidal particles comprise a material selected from the group consisting of Al 2 O 3 , SiO 2 , CeO 2 , ZrO 2 , and TiO 2 .

33. The method of claim 28 , wherein the droplets comprise from 1 to 50 weight percent of the precursor.

34. The method of claim 28 , wherein the droplets comprise from 1 to 10 weight percent of the precursor.

35. The method of claim 28 , wherein the liquid is aqueous.

36. The method of claim 28 , wherein the liquid is organic.

37. The method of claim 36 , wherein the organic liquid comprises a member selected from the group of consisting of toluene and ethylene glycol.

38. The method of claim 1 , wherein the forming comprises heating the aerosol stream in a thermal reactor.

39. The method of claim 38 , wherein the thermal reactor is a tubular furnace reactor.

40. The method of claim 38 , wherein the thermal reactor is a plasma reactor.

41. The method of claim 38 , wherein the thermal reactor is a flame reactor.

42. The method of claim 38 , wherein during the forming, the aerosol stream attains a maximum average stream temperature of greater than 800° C.

43. The method of claim 38 , wherein during the forming, the aerosol stream attains a maximum average stream from 400° C. to 1200° C.

44. The method of claim 38 , wherein during the forming, the aerosol stream attains a maximum average stream temperature of from 600° C. to 1100° C.

45. The method of claim 38 , wherein the thermal reactor comprises a heating zone, and wherein the residence time of the aerosol stream in the heating zone is less than 0.5 second.

46. The method of claim 1 , wherein the droplets have a weight average size of from 1 micron to 5 microns.

47. The method of claim 46 , wherein as generated, the aerosol stream comprises at least 1×10 6 of the droplets per cubic centimeter.

48. The method of claim 46 , wherein the generating comprises forming the droplets from a liquid feed and dispersing the droplets in a carrier gas.

49. The method of claim 48 , wherein as generated, the aerosol stream comprises greater than 0.04 milliliters of the liquid feed per liter of the carrier gas.

50. The method of claim 1 , comprising:

cooling the abrasive particles, the cooling comprising introducing a quench gas into the aerosol stream to lower the temperature of the aerosol stream.

51. The method of claim 50 , wherein during the introducing, the quench gas is introduced into the aerosol stream at a velocity greater than a thermophoretic velocity of the abrasive particles in the aerosol stream.

52. The method of claim 51 , wherein the quench gas lowers the temperature of the aerosol stream from above to below 200° C.

53. The method of claim 52 , wherein the quench gas cools the aerosol stream to a temperature of from 50° C. to 120° C.

54. The method of claim 1 , wherein the forming the abrasive particles comprises forming particles and then modifying the particles while in the aerosol stream.

55. The method of claim 54 , wherein the modifying comprises structural modification of the particles.

56. The method of claim 55 , wherein the structural modification comprises modifying the crystalline structure of the particles.

57. The method of claim 55 , wherein the structural modification comprises annealing the abrasive particles.

58. The method of claim 54 , wherein the modifying comprises compositional modification of the particles.

59. The method of claim 58 , wherein the compositional modification comprises forming on the particles a coating comprising a coating material.

60. The method of claim 59 , wherein the coating has an average thickness of not greater than 100 nanometers.

61. The method of claim 59 , wherein the coating has an average thickness of not greater than 50 nanometers.

62. The method of claim 61 , wherein the coating has an average thickness of at least 5 nanometers.

63. The method of claim 59 , wherein the coating material is non-metallic.

64. The method of claim 59 , wherein the coating material is a metal oxide.

65. The method of claim 64 , wherein the metal oxide is selected from the group consisting of Al 2 O 3 and CeO 2 .

66. The method of claim 64 , wherein the particles comprise SiO 2 and the coating material is Al 2 O 3 .

67. The method of claim 64 , wherein the particles comprise SiO 2 and the coating material is CeO 2 .

68. The method of claim 59 , wherein the coating material is organic.

69. The method of claim 68 , wherein the coating material is polymethylmethacrylate.

70. The method of claim 68 , wherein the coating material is polystyrene.

71. The method of claim 59 , wherein the coating is a monolayer.

72. The method of claim 59 , wherein the forming a coating comprises reaction of SiCl 4 .

73. The method of claim 59 , wherein the forming a coating comprises reaction of Si(OEt) 4 .

74. The method of claim 59 , wherein the forming a coating comprises reacting an organic or inorganic molecule with a surface of the particles.

75. The method of claim 59 , wherein the forming a coating comprises reacting a surface of the particles with a functionalized organo silane compound.

76. The method of claim 75 , wherein the functionalized organo silane compound is a halo-silane.

77. The method of claim 75 , wherein the functionalized organo silane compound is an amino-silane.

78. The method of claim 75 , wherein the functionalized organo silane compound is hexamethyldisilazane.

79. The method of claim 75 , wherein the functionalized organo silane compound is trimethylsilychloride.

80. The method of claim 59 , wherein the forming a coating comprises condensing a volatile coating material on the particles.

81. The method of claim 1 , wherein the slurry comprises from 0.5 to 60 weight percent of the abrasive particles.

82. The method of claim 1 , wherein the slurry comprises from 1 to 20 weight percent of the abrasive particles.

83. The method of claim 1 , wherein the slurry comprises from 7 to 15 weight percent of the abrasive particles.

84. The method of claim 1 , wherein the slurry comprises water.

85. The method of claim 1 , wherein the slurry comprises a surfactant.

86. The method of claim 85 , wherein the slurry comprises no greater than 20 weight percent of the surfactant.

87. The method of claim 85 , wherein the surfactant is selected from the group consisting of alkali sulfonates, sulfates, lignosulfonates, carboxylates and phosphates.

88. The method of claim 1 , wherein the slurry comprises an oxidizing agent.

89. The method of claim 88 , wherein the slurry comprises no greater than 20 weight percent of the oxidizing agent.

90. The method of claim 88 , wherein the oxidizing agent is selected from the group consisting of metal salts, chlorates, perchlorates, chlorites, iodates, nitrates, persulfates, peroxides, ozinated water and oxygenated water.

91. The method of claim 1 , wherein the slurry comprises a complexing agent.

92. The method of claim 91 , wherein the complexing agent is ammonia.

93. The method of claim 1 , wherein the abrasive particles are first abrasive particles and the slurry further comprises second abrasive particles of different composition.

94. The method of claim 93 , wherein the first abrasive particles comprise SiO 2 .

95. The method of claim 94 , wherein the second abrasive particles comprise CeO 2 .

96. The method of claim 1 , comprising:

providing the slurry to a polishing pad.

97. The method of claim 96 , comprising:

placing the slurry between the polishing pad and a metal layer of an integrated circuit wafer; and

removing the metal layer from the integrated circuit wafer.

98. The method of claim 1 , comprising:

applying the slurry to an integrated circuit wafer.

99. The method of claim 1 , comprising:

applying the slurry to a silicon substrate.

100. The method of claim 1 , comprising:

after the forming, cooling the aerosol stream, the cooling comprising passing the aerosol through a perforated conduit while introducing a quench gas into the perforated conduit through openings in a wall of the perforated conduit; and

wherein the generating comprises sweeping away with carrier gas the droplets from a reservoir of the flowable medium ultrasonically energized by a plurality of ultrasonic transducers underlying the reservoir.