Laser material micromachining with green femtosecond pulses

• US 20060207976A1
• Filed: 01/20/2006
• Published: 09/21/2006
• Est. Priority Date: 01/21/2005
• Status: Abandoned Application

• Current Assignee: IMRA America Incorporated (Aisin Corp.)
• Original Assignee: IMRA America Incorporated (Aisin Corp.)
• Inventors: Bovatsek, James M., Arai, Alan Y., Shah, Lawrence, Yoshino, Fumiyo
• Application Number:
  US11/336,383
• Publication Number:
  US 20060207976A1
• Time in Patent Office: Days
• US Class Current: 219/121.690
• CPC Class Codes: B23K 2103/172 wherein at least one of the layers is non-metallic
• CPC Class Codes: B23K 2103/30 Organic material
• CPC Class Codes: B23K 2103/42 Plastics B23K2103/16 takes precedence
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 26/0006 taking account of the properties of the material involved B23K26/32, B23K26/40 take precedence
• CPC Class Codes: B23K 26/0624 using ultrashort pulses, i.e. pulses of 1ns or less
• CPC Class Codes: B23K 26/364 for making a groove or trench, e.g. for scribing a break initiation groove
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: C03B 33/0222 Scoring using a focussed radiation beam, e.g. laser
• CPC Class Codes: H01S 3/0057 Temporal shaping, e.g. pulse compression, frequency chirping soliton generation and propagation G02F1/3513, H01S3/063 and H01S3/108

Abstract

Various embodiments of a system described herein relate to micromachining materials using ultrashort visible laser pulses. The ultrashort laser pulses may be green and have a wavelength between about 500 to 550 nanometers in some embodiments. Additionally, the pulses may have a pulse duration of less than one picosecond in certain embodiments.

Claims

1. A method comprising:

producing a visible light beam comprising femtosecond optical pulses having a wavelength between about 490 and 550 nanometers;

micromachining a region of a surface by directing at least a portion of said visible light beam into said region of said surface.

2. The method of claim 1, wherein said visible light beam is green.

3. The method of claim 2, wherein said femtosecond optical pulses have a wavelength between about 500 and 550 nanometers.

4. The method of claim 1, wherein said femtosecond optical pulses have a pulse duration between about 200 and 500 femtoseconds.

5. The method of claim 1, wherein said femtosecond optical pulses have a pulse duration between about 300 and 700 femtoseconds in duration.

6. The method of claim 1, further comprising producing infrared light and frequency doubling said infrared light to produce said visible light beam.

7. The method of claim 6, wherein said frequency doubling comprises second harmonic generation.

8. The method of claim 6, wherein said infrared light comprises laser light of about 1040 nanometers and said visible light beam comprises laser light of about 520 nanometers.

9. The method of claim 6, further comprising pulsing said infrared light at a repetition rate between about 100 kHz to 5 MHz.

10. The method of claim 1, wherein said micromachining comprises cutting a portion of said surface.

11. The method of claim 1, wherein said micromachining comprises drilling or milling a portion of said surface.

12. The method of claim 1, wherein said micromachining comprises scribing or grooving a portion of said surface.

13. The method of claim 1, wherein said surface comprises a metal.

14. The method of claim 1, wherein said surface comprises a semiconductor.

15. The method of claim 1, wherein said surface comprises a dielectric.

16. The method of claim 15, wherein said dielectric comprises glass or quartz.

17. The method of claim 16, wherein said glass comprises borosilicate glass.

18. The method of claim 1, wherein surface comprises crystal or polymer.

19. The method of claim 1, wherein said surface comprises a thin film on a substrate.

20. The method of claim 19, wherein said thin film comprises a metal.

21. The method of claim 19, wherein said substrate comprises dielectric.

22. The method of claim 19, wherein said substrate comprises glass or crystal.

23. The method of claim 19, wherein said substrate comprises a semiconductor.

24. The method of claim 1, wherein said surface comprises alternating layers comprising different materials.

25. The method of claim 1, wherein said micromachining produces a micromachined edge that is substantially smooth.

26. The method of claim 25, wherein said micromachined edge has a surface roughness less than about 1 micrometer RMS

27. The method of claim 25, wherein said micromachined edge has a surface roughness less than about 100 nanometers RMS.

28. The method of claim 25, wherein said micromachined edge has a surface roughness less than about 10 nanometers RMS.

29. A system for micromachining, said system comprising:

a light source producing a beam of visible light comprising femtosecond pulses having a wavelength between about 490 and 550 nanometers; and

material positioned in said beam,

wherein said material is micromachined by said beam.

30. The system of claim 29, wherein said light source comprises a laser.

31. The system of claim 29, wherein said light source is configured to output a green light beam having a wavelength of between about 500 to 550 femtoseconds.

32. The system of claim 29, wherein said light source is configured to output pulses having a duration of between about 200 to 500 femtoseconds.

33. The system of claim 29, wherein said light source is configured to output pulses having a duration of between about 300 to 700 femtoseconds.

34. The system of claim 29, wherein said visible laser light source comprises an infrared laser and a frequency doubler.

35. The system of claim 34, wherein said infrared laser comprises a Yb-doped fiber laser.

36. The system of claim 35, wherein said light source further comprises a pulse stretcher, an amplifier, and a compressor.

37. The system of claim 29, wherein said micromachining comprises cutting a portion of said material.

38. The system of claim 29, wherein said micromachining comprises drilling or milling a portion of said material.

39. The system of claim 29, wherein said micromachining comprises scribing or grooving a portion of said material.

40. The system of claim 29, wherein said material comprises a metal.

41. The system of claim 29, wherein said material comprises a semiconductor.

42. The system of claim 29, wherein said material comprises a dielectric.

43. The system of claim 42, wherein said dielectric comprises glass or quartz.

44. The system of claim 43, wherein said glass comprises borosilicate glass.

45. The system of claim 29, wherein material comprises crystal or polymer.

46. The system of claim 29, wherein said material comprises a thin film on a substrate.

47. The system of claim 46, wherein said thin film comprises a metal.

48. The system of claim 46, wherein said substrate comprises dielectric.

49. The system of claim 46, wherein said substrate comprises glass or crystal.

50. The system of claim 46, wherein said substrate comprises a semiconductor.

51. The system of claim 29, wherein said material comprises alternating layers comprising different materials.

52. The system of claim 29, wherein said micromachining produces a micromachined edge that is substantially smooth.

53. The system of claim 52, wherein said micromachined edge has a surface roughness less than about 1 micrometer RMS

54. The system of claim 52, wherein said micromachined edge has a surface roughness less than about 100 nanometers RMS.

55. The system of claim 52, wherein said micromachined edge has a surface roughness less than about 10 nanometers RMS.

56. A system for performing micromachining on an object, said system comprising:

a visible laser light source that outputs a visible light beam comprising femtosecond duration optical pulses having a wavelength between about 490 and 550 nanometers and illuminates a spatial region of said object with said visible light; and

a translation system for translating said beam or said spatial region;

wherein said translation system is configured to alter the relative position of the beam and object such that said visible laser beam micromachines the object.

57. The system of claim 56, wherein said visible laser light source comprises an infrared laser and a frequency doubler.

58. The system of claim 57, wherein said infrared laser comprises a Yb-doped fiber laser.

59. The system of claim 57, wherein said infrared laser comprises a laser that operates at a wavelength of approximately 1045 nanometers and said frequency doubler comprises a nonlinear optical element that produces light having a wavelength of about 522.5 nanometer through second harmonic generation.

60. The system of claim 56, wherein said visible laser light source has a repetition rate between about 100 kHz to 5 MHz.

61. The system of claim 56, further comprising optics disposed to receive said visible light beam output from said visible laser light source and illuminate said spatial region with said visible light.

62. The system of claim 61, wherein said optics comprises a microscope objective.

63. The system of claim 56, wherein said translation system comprises a translation stage on which said object is disposed.

64. The system of claim 56, wherein said translation system comprises a movable mirror.

65. The system of claim 56, wherein said visible laser light source is configured to output optical pulses having a duration of between about 200 to 500 femtoseconds.

66. The system of claim 56, wherein said visible laser light source is configured to output optical pulses having a duration of between about 300 to 700 femtoseconds.