US 7,556,896 B2
Inspection method and photomask
Kazuya Fukuhara, Tokyo (Japan); Satoshi Tanaka, Kanagawa (Japan); and Soichi Inoue, Kanagawa (Japan)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan)
Filed on Nov. 30, 2006, as Appl. No. 11/606,121.
Application 11/606121 is a division of application No. 10/615228, filed on Jul. 09, 2003, granted, now 7,186,485.
Claims priority of application No. P2002-203194 (JP), filed on Jul. 11, 2002.
Prior Publication US 2007/0071306 A1, Mar. 29, 2007
Int. Cl. G03F 9/00 (2006.01)
U.S. Cl. 430—5  [430/30; 382/145] 18 Claims
 
1. A photomask, comprising:
a transparent substrate having a first surface and a second surface opposite to the first surface;
a first aberration measurement unit disposed on a first region of the first surface;
a second aberration measurement unit disposed on a second region of the first surface, the second region away from the first region; and
a first polarizer disposed on the second surface so as to be opposite to the first aberration measurement unit.