	US 7,575,834 B2
	Phase shifter for laser annealing
Masayuki Jyumonji, Kawasaki (Japan)
Assigned to Advanced LCD Technologies Development Center Co., Ltd., Yokohama-shi (Japan)
Filed on Mar. 20, 2006, as Appl. No. 11/276,992.
Claims priority of application No. 2005-165476 (JP), filed on Jun. 06, 2005.
Prior Publication US 2006/0275673 A1, Dec. 07, 2006
Int. Cl. G03F 1/00 (2006.01)

U.S. Cl. 430—5

7 Claims

1. A phase shifter for laser annealing which irradiates the surface to be treated with a luminous flux having a regular intensity distribution during the laser annealing, the shifter comprising:

a first transparent layer having a first refractive index in a wavelength of laser light for use;

a second transparent layer disposed on the first transparent layer and having a second refractive index which is different from the first refractive index in the wavelength of the laser light for use;

a third transparent layer disposed on the second transparent layer and having the first refractive index in the wavelength of the laser light for use; and

a spacer which is disposed between the first transparent layer and the third transparent layer along peripheral edge portions of the first and third transparent layers and which blocks the second transparent layer from the outside so as to prevent particles from entering between the first transparent layer and the third layer,

wherein a two-dimensional pattern of fine stepped portions is formed in at least one of an interface between the first transparent layer and the second transparent layer and an interface between the second transparent layer and the third transparent layer, whereby a phase difference is made between the laser light passed through the stepped portion and the laser light passed through a portion other than the stepped portion,

and wherein a thickness of the second transparent layer is selected so as to prevent interference of the laser light while the laser light passes through the second transparent layer.