US 7,579,122 B2
Method of exposure and attenuated type phase shift mask
Yukio Taniguchi, Yokomaha (Japan)
Assigned to Kabushiki Kaisha Ekisho Sentan Gijutsu Kihatsu Center, Yokohama (Japan)
Filed on Apr. 05, 2006, as Appl. No. 11/399,288.
Claims priority of application No. 2005-110119 (JP), filed on Apr. 06, 2005.
Prior Publication US 2006/0240337 A1, Oct. 26, 2006
Int. Cl. G03F 1/00 (2006.01)
U.S. Cl. 430—5 4 Claims
OG exemplary drawing
 
1. A method of exposing a surface to be exposed by using an attenuated type phase shift mask having a reference area allowing a light radiated from a light source to pass and an amplitude and phase modulation area allowing a part of said light to pass,
wherein the phase modulation amount of the amplitude and phase modulation area relative to the reference area of said attenuated type phase shift mask is {360°×n +(182° to 203°)} (n is an integer) for obtaining a light intensity distribution that is symmetrical with respect to the image plane, making on the positive side when a wavefront of a light immediately passing said phase shift mask shifts to the side of said light source, and on the negative side when the wavefront of the light immediately after passing said phase shift mask shifts to the side of said surface to be exposed.