Systems and methods for generating laser light shaped as a line beam

• US 20070097511A1
• Filed: 10/28/2005
• Published: 05/03/2007
• Est. Priority Date: 10/28/2005
• Status: Active Grant

• Current Assignee: CARL Zeiss SMT GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: Cymer Incorporated (ASML Holding NV)
• Inventors: Muenz, Holger, Shklover, Vitaliy, Cefalo, Albert, Knowles, David, Das, Palash
• Granted Patent: US 7,471,455 B2
• Time in Patent Office: Days
• US Class Current: 359/618
• CPC Class Codes: G02B 19/0009 having refractive surfaces only
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0052 the light source comprising a laser diode coupling into light guides using intermediate optical elements G02B6/4204; semiconductor lasers having optical devices external to the laser cavity H01S5/005
• CPC Class Codes: G02B 27/095 Refractive optical elements
• CPC Class Codes: G02B 27/0977 Reflective elements
• CPC Class Codes: G02B 27/0988 Diaphragms, spatial filters, masks for removing or filtering a part of the beam
• CPC Class Codes: G02B 7/004 Manual alignment, e.g. micromanipulators

Abstract

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, d₁, along the beam path from the film and a second short-axis element having an edge positioned at a distance, d₂, along the beam path from the film, with d₂<d₁. 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.

Claims

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, d₁, 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, d₂, along the beam path from said film, with d₂<

d₁; 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 as 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, d₁, 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, d₂, along the beam path from said film, with d₂<

d₁; 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, d₁, along the beam path from said film and said edge of said second short-axis element is positioned at a distance, d₂, along the beam path from said film, with d₂<

d₁.

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.