Laser irradiation apparatus, laser irradiation method and method for manufacturing semiconductor device

• US 7,551,655 B2
• Filed: 11/29/2004
• Issued: 06/23/2009
• Est. Priority Date: 12/02/2003
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamamoto, Yoshiaki, Tanaka, Koichiro
• Primary Examiner(s): Nguyen; Dung T
• Application Number:
  US10/997,868
• Publication Number:
  US 20050115930A1
• Time in Patent Office: 1,667 Days
• Field of Search: 372/25, 372/28
• US Class Current: 372/25
• CPC Class Codes: B23K 26/0622 by shaping pulses
• CPC Class Codes: B23K 26/064 by means of optical elements, e.g. lenses, mirrors or prisms
• CPC Class Codes: B23K 26/0643 comprising mirrors
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B23K 26/0665 by beam condensation on the workpiece, e.g. for focusing
• CPC Class Codes: B23K 26/0853 Devices involving movement of the workpiece in at least in two axial directions, e.g. in a plane
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• CPC Class Codes: H01L 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02595 polycrystalline
• CPC Class Codes: H01L 21/02678 Beam shaping, e.g. using a mask
• CPC Class Codes: H01L 21/02686 Pulsed laser beam
• CPC Class Codes: H01L 21/02691 Scanning of a beam

Abstract

The object of the present invention is to provide a laser irradiation apparatus being able to enlarge the beam spot to a large degree compared with that of the CW laser, to suppress the thermal damage to the glass substrate, and to form an aggregation of crystal grains including a single crystal extending long in a scanning direction by growing the crystal continuously in the scanning direction. The laser irradiation of the present invention comprises a pulsed laser oscillator, a non-linear optical element for converting the wavelength of the laser light emitted from the pulsed laser oscillator, and an optical system for condensing the laser light whose wavelength is converted on a semiconductor film, wherein the pulsed laser oscillator has a repetition rate in the range of 10 MHz to 100 GHz.

Claims

1. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a laser light;

an optical system configured to introduce the laser light to a processing object,

wherein the pulsed laser introduced to the processing object has a pulse repetition rate of 10 MHz or more, and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

2. The laser irradiation apparatus according to claim 1 further comprising a stage for irradiating the laser light to a processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

3. The laser irradiation apparatus according to claim 1 further comprising a stage for irradiating the laser light to a processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

4. The laser irradiation apparatus according to claim 1, wherein the processing object comprises a semiconductor film.

5. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a laser light;

an optical system configured to introduce the laser light to a processing object,

wherein the pulsed laser introduced to the processing object has a pulse repetition rate from 10 MHz to 100 GHz, and

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

6. The laser irradiation apparatus according to claim 5 further comprising a stage for irradiating the laser light to a processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

7. The laser irradiation apparatus according to claim 5 further comprising a stage for irradiating the laser light to a processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

8. The laser irradiation apparatus according to claim 5, wherein the processing object comprises a semiconductor film.

9. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a laser light;

a non-linear optical element configured to convert a wavelength of the laser light; and

an optical system configured to introduce the laser light whose wavelength is converted to a processing object, and to condense the laser light whose wavelength is converted on a processing object,

wherein the pulsed laser introduced to the processing object has a pulse repetition rate of 10 MHz or more, and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

10. The laser irradiation apparatus according to claim 9, wherein the laser light whose wavelength is converted has a second harmonic.

11. The laser irradiation apparatus according to claim 9, wherein the processing object comprises a semiconductor film.

12. The laser irradiation apparatus according to claim 9 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

13. The laser irradiation apparatus according to claim 9 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

14. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a pulse laser;

a non-linear optical element configured to convert a wavelength of the laser light; and

an optical system configured to introduce the laser light whose wavelength is converted to a processing object, and to condense the laser light whose wavelength is converted on a processing object,

wherein the pulsed laser introduced to the processing object has a pulse repetition rate 10 MHz or more, and

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

15. The laser irradiation apparatus according to claim 14, wherein the laser light whose wavelength is converted has a second harmonic.

16. The laser irradiation apparatus according to claim 14, wherein the processing object comprises a semiconductor film.

17. The laser irradiation apparatus according to claim 14 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

18. The laser irradiation apparatus according to claim 14 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

19. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a pulse laser;

a non-linear optical element configured to convert a wavelength of the laser light; and

an optical system configured to introduce the laser light whose wavelength is converted to a processing object, and to condense the laser light whose wavelength is converted on a processing object,

wherein the pulsed laser oscillator has a pulse repetition rate from 10 MHz to 100 GHz; and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

20. The laser irradiation apparatus according to claim 19, wherein the laser light whose wavelength is converted has a second harmonic.

21. The laser irradiation apparatus according to claim 19, wherein the processing object comprises a semiconductor film.

22. The laser irradiation apparatus according to claim 19 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

23. The laser irradiation apparatus according to claim 19 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

24. A laser irradiation apparatus comprising:

a pulsed laser oscillator configured to supply a pulse laser;

a non-linear optical element configured to convert a wavelength of the laser light; and

an optical system configured to introduce the laser light whose wavelength is converted to a processing object, and to condense the laser light whose wavelength is converted on a processing object,

wherein the pulsed laser oscillator has a pulse repetition rate from 10 MHz to 100 GHz; and

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

25. The laser irradiation apparatus according to claim 24, wherein the laser light whose wavelength is converted has a second harmonic.

26. The laser irradiation apparatus according to claim 24, wherein the processing object comprises a semiconductor film.

27. The laser irradiation apparatus according to claim 24 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

28. The laser irradiation apparatus according to claim 24 further comprising a stage for irradiating the laser light to the processing object,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

29. A laser irradiation method comprising the step of irradiating a processing object with pulsed laser light at a pulse repetition rate of 10 MHz or more,

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

30. The laser irradiation method according to claim 29, wherein the processing object comprises a semiconductor film.

31. The laser irradiation method according to claim 29 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

32. The laser irradiation method according to claim 29 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

33. A laser irradiation method comprising the step of irradiating a processing object with pulsed laser light at a pulse repetition rate from 10 MHz to 100 GHz,

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

34. The laser irradiation method according to claim 33, wherein the processing object comprises a semiconductor film.

35. The laser irradiation method according to claim 33 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

36. The laser irradiation method according to claim 33 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

37. A laser irradiation method comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with the laser light whose wavelength is converted,

wherein a pulse repetition rate of the laser light irradiated to the processing object is 10 MHz or more,

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

38. The laser irradiation method according to claim 37, wherein the laser light whose wavelength is converted has a second harmonic.

39. The laser irradiation method according to claim 37 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

40. The laser irradiation method according to claim 37 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

43. The laser irradiation method according to claim 37, wherein the processing object comprises a semiconductor film.

41. A laser irradiation method comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with the laser light whose wavelength is converted,

wherein a pulse repetition rate of the laser light irradiated to the processing object is 10 MHz or more,

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

42. The laser irradiation method according to claim 41, wherein the laser light whose wavelength is converted has a second harmonic.

44. The laser irradiation method according to claim 41, wherein the processing object comprises a semiconductor film.

45. The laser irradiation method according to claim 41 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

46. The laser irradiation method according to claim 41 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

47. A laser irradiation method comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with the laser light whose wavelength is converted,

wherein a pulse repetition rate is from 10 MHz to 100 GHz; and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

48. The laser irradiation method according to claim 47, wherein the laser light whose wavelength is converted has a second harmonic.

49. The laser irradiation method according to claim 47, wherein the processing object comprises a semiconductor film.

50. The laser irradiation method according to claim 47 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

51. The laser irradiation method according to claim 47 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

52. A laser irradiation method comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with the laser light whose wavelength is converted,

wherein a pulse repetition rate is from 10 MHz to 100 GHz; and

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

53. The laser irradiation method according to claim 52, wherein the laser light whose wavelength is converted has a second harmonic.

54. The laser irradiation method according to claim 52, wherein the processing object comprises a semiconductor film.

55. The laser irradiation method according to claim 52 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

56. The laser irradiation method according to claim 52 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

57. A method for manufacturing a semiconductor device comprising the step of irradiating a processing object with pulsed laser light at a pulse repetition rate of 10 MHz or more,

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

58. The method for manufacturing a semiconductor device according to claim 57, wherein the processing object comprises a semiconductor film.

59. The method for manufacturing a semiconductor device according to claim 57 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

60. The method for manufacturing a semiconductor device according to claim 57 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

61. A method for manufacturing a semiconductor device comprising the step of irradiating a processing object with pulsed laser light at a pulse repetition rate from 10 MHz to 100 GHz,

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

62. The method for manufacturing a semiconductor device according to claim 61, wherein the processing object comprises a semiconductor film.

63. The method for manufacturing a semiconductor device according to claim 61 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

64. The method for manufacturing a semiconductor device according to claim 61 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

65. A method for manufacturing a semiconductor device comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with laser light whose wavelength is converted,

wherein a pulse repetition rate of the laser light irradiated to the processing object is 10 MHz or more, and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

66. The method for manufacturing a semiconductor device according to claim 65, wherein the laser light whose wavelength is converted has a second harmonic.

67. The method for manufacturing a semiconductor device according to claim 65, wherein the processing object comprises a semiconductor film.

68. The method for manufacturing a semiconductor device according to claim 65 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

69. The method for manufacturing a semiconductor device according to claim 65 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

70. A method for manufacturing a semiconductor device comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with laser light whose wavelength is converted,

wherein a pulse repetition rate of the laser light irradiated to the processing object is 10 MHz or more,

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

71. The method for manufacturing a semiconductor device according to claim 70, wherein the laser light whose wavelength is converted has a second harmonic.

72. The method for manufacturing a semiconductor device according to claim 70, wherein the processing object comprises a semiconductor film.

73. The method for manufacturing a semiconductor device according to claim 70 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

74. The method for manufacturing a semiconductor device according to claim 70 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

75. A method for manufacturing a semiconductor device comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with laser light whose wavelength is converted,

wherein a pulse repetition rate is from 10 MHz to 100 GHz; and

wherein an inequality of ct<

2nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

76. The method for manufacturing a semiconductor device according to claim 75, wherein the laser light whose wavelength is converted has a second harmonic.

77. The method for manufacturing a semiconductor device according to claim 75, wherein the processing object comprises a semiconductor film.

78. The method for manufacturing a semiconductor device according to claim 75 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

79. The method for manufacturing a semiconductor device according to claim 75 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.

80. A method for manufacturing a semiconductor device comprising the steps of:

converting a wavelength of laser light emitted from a pulsed laser oscillator using a non-linear optical element; and

irradiating a processing object with laser light whose wavelength is converted,

wherein a pulse repetition rate is from 10 MHz to 100 GHz; and

wherein an inequality of ct<

4nd is satisfied where c is a speed of light in vacuum, n is a refractive index of a substrate with the processing object formed thereover, d is a thickness of the substrate, and t is a pulse width of the laser light.

81. The method for manufacturing a semiconductor device according to claim 80, wherein the laser light whose wavelength is converted has a second harmonic.

82. The method for manufacturing a semiconductor device according to claim 80, wherein the processing object comprises a semiconductor film.

83. The method for manufacturing a semiconductor device according to claim 80 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is in the range of several tens to several thousand mm/s.

84. The method for manufacturing a semiconductor device according to claim 80 further comprising the step of irradiating the processing object mounted on a stage,

wherein a scanning speed of the stage is 100 to 2000 mm/s.