| US 7,463,350 B2 | ||
| Method and apparatus for detecting defects of a sample using a dark field signal and a bright field signal | ||
| Hidetoshi Nishiyama, Fujisawa (Japan); Minoru Yoshida, Yokohama (Japan); Yukihiro Shibata, Fujisawa (Japan); and Shunji Maeda, Yokohama (Japan) | ||
| Assigned to Hitachi High-Technologies Corporation, Tokyo (Japan) | ||
| Filed on Nov. 05, 2004, as Appl. No. 10/981,721. | ||
| Claims priority of application No. 2003-375093 (JP), filed on Nov. 05, 2003; and application No. 2004-001603 (JP), filed on Jan. 07, 2004. | ||
| Prior Publication US 2005/0110988 A1, May 26, 2005 | ||
| Int. Cl. G01N 21/00 (2006.01) | ||
| U.S. Cl. 356—237.4 | 9 Claims |
| 1. An apparatus for detecting defects of a sample, comprising:
an illumination light source that emits pulsed ultraviolet laser light;
a polarized light splitter unit that splits each pulse of the pulsed ultraviolet laser light emitted from the illumination
light source into plural pulses of P-polarized laser light and S-polarized laser light;
an irradiating unit that selectively irradiates a sample with the split ultraviolet P-polarized and S-polarized ultraviolet
laser light split by the polarized light splitter unit from a perpendicular direction with the split S-polarized ultraviolet
laser light and from an oblique direction to the sample with the split P-polarized ultraviolet laser light;
a light detecting unit that detects light from the sample irradiated with the split polarized ultraviolet laser light by the
selected oblique irradiation of the irradiating unit with the split P-polarized ultraviolet laser and by the selected perpendicular
irradiation of the irradiating unit with the split S-polarized ultraviolet laser light; and
a defect detecting unit that detects defects of the sample by processing a signal outputted from the light detecting unit
which includes a dark field signal obtained by separately detecting the light from the sample caused by the selected oblique
irradiation with the split P-polarized ultraviolet laser light and a bright field signal obtained by separately detecting
the light from the sample caused by the selected perpendicular irradiation with the split S-polarized ultraviolet laser light.
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