Systems and methods for generating laser light shaped as a line beam
View Patent ↗Systems and methods are disclosed for shaping a laser beam for interaction with a film in which the laser beam travels along a beam path and defines a short-axis and a long-axis. In one aspect, the system may include a first short-axis element having an edge positioned at a distance, d 1 , along the beam path from the film and a second short-axis element having an edge positioned at a distance, d 2 , along the beam path from the film, with d 2 <d 1 . An optic may be positioned along the beam path between the second element and the film for focusing the beam in the short-axis for interaction with the film. In another aspect, a system may be provided having a mechanism operative to selectively adjust the curvature of one or both of the edges of the short-axis element.
1. An apparatus for shaping a laser beam for interaction with a film, the beam traveling along a beam path and defining a short-axis and a long-axis, said axes being mutually orthogonal, said apparatus comprising:
a first short-axis element positioned for illumination by a portion of said beam and having an edge positioned at a distance, d 1 , along the beam path from said film;
a second short-axis element positioned for illumination by a portion of said beam and having an edge positioned at a distance, d 2 , along the beam path from said film, with d 2 <d 1 ; and
an optic positioned along the beam path between said second short-axis element and said film for focusing said beam in the short-axis for interaction with the film.
2. An apparatus as recited in claim 1 wherein said edge of said first short-axis element is aligned substantially parallel to said edge of said second short-axis element.
3. An apparatus as recited in claim 1 wherein said first short-axis element is a reflective beam dividing element.
4. An apparatus as recited in claim 1 wherein said first short-axis element is an absorptive stop.
5. An apparatus as recited in claim 1 wherein said first short-axis element is a refractive beam dividing element.
6. An apparatus as recited in claim 1 further comprising a focusing optic positioned along the beam path between a laser source and said first short-axis element.
7. An apparatus its recited in claim 1 further comprising a short-axis homogenizing optic positioned along the beam path between a laser source and said first short-axis element.
8. A sequential lateral solidification apparatus for melting an amorphous silicon film deposited on a substrate with a laser beam shaped as a line beam, the beam traveling along a beam path and defining a short-axis and a long-axis, said axes being mutually orthogonal, said apparatus comprising:
a moveable stage for holding the substrate;
a laser source generating a laser beam on said beam path;
a first short-axis element positioned for illumination by a portion of said beam and having an edge positioned at a distance, d 1 , along the beam path from said film;
a second short-axis element positioned for illumination by a portion of said beam and having an edge positioned at a distance d 2 , along the beam path from said film, with d 2 <d 1 ; and
an optic positioned along the beam path between said second short-axis element and said film for focusing said beam in the short-axis for interaction with the film.
9. An apparatus as recited in claim 8 wherein said edge of said first short-axis element is aligned substantially parallel to said edge of said second short-axis element.
10. An apparatus as recited in claim 8 wherein said first short-axis element is a reflective beam dividing element.
11. An apparatus as recited in claim 8 wherein said first short-axis element is an absorptive stop.
12. An apparatus as recited in claim 8 wherein said first short-axis element is a refractive beam dividing element.
13. An apparatus as recited in claim 8 further comprising a focusing optic positioned along the beam path between a laser source and said first short axis element.
14. An apparatus as recited in claim 8 further comprising a short-axis homogenizing optic positioned along the beam path between a laser source and said first short axis element.
15. An apparatus for shaping a laser beam for interaction with a film, the beam traveling along a beam path and defining a short-axis and a long-axis, said axes being mutually orthogonal, said apparatus comprising:
a first short-axis element positioned for illumination by a portion of said beam and having an edge;
a second short-axis element positioned for illumination by a portion of said beam and having an edge;
a mechanism adjusting the curvature of said edge of said first short-axis element; and
an optic positioned along the beam path between said first short-axis element and said film for focusing said beam in the short-axis for interaction with the film.
16. An apparatus as recited in claim 15 wherein said mechanism is operative to adjust the curvature of said edge of said first short-axis element in a plane normal to said beam path at the first short-axis element.
17. An apparatus as recited in claim 15 wherein said edge of said first short-axis element is positioned at a distance, d 1 , along the beam path from said film and said edge of said second short-axis element is positioned at a distance, d 2 , along the beam path from said film, with d 2 <d 1 .
18. An apparatus as recited in claim 15 wherein said first short-axis element is a reflective beam dividing element.
19. An apparatus as recited in claim 15 wherein said first short-axis element is an absorptive stop.
20. An apparatus as recited in claim 15 wherein said first short-axis element is a refractive beam dividing element.