| US 7,498,596 B2 | ||
| Exposure method that obtains, prior to exposure, reticle surface form data and measurement position error, for scanning control | ||
| Kohei Maeda, Utsunomiya (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on May 23, 2006, as Appl. No. 11/438,459. | ||
| Claims priority of application No. 2005-162718 (JP), filed on Jun. 02, 2005. | ||
| Prior Publication US 2006/0273267 A1, Dec. 07, 2006 | ||
| Int. Cl. H01L 21/027 (2006.01); G03B 27/42 (2006.01); G01N 21/00 (2006.01) | ||
| U.S. Cl. 250—559.29 [250/559.39; 356/614; 355/53; 355/55] | 2 Claims |
| 1. An exposure method for exposing a pattern of a reticle onto a plate, via a projection optical system, while synchronously
scanning the reticle and the plate, said exposure method comprising:
a first measuring step of measuring a surface shape of the reticle;
a determining step of determining an error measurement position based on a measuring result of said first measuring step;
a second measuring step of remeasuring the surface shape of the reticle without measuring the error measurement position;
and
a controlling step of controlling synchronous scanning of the reticle and the plate based on a measuring result of said second
measuring step,
wherein said first measuring step includes:
(i) a first substep for measuring a surface position of the reticle at plural measurement positions that are arranged in a
scanning direction by scanning the reticle at a scan speed used for exposure; and
(ii) a second substep for measuring the surface position of the reticle at positions that are shifted from the plural measurement
positions in the scanning direction by an equal distance by scanning the reticle in a direction opposite to that of said first
substep at the scan speed used for exposure.
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