| 摘要 |
PURPOSE:To provide a pattern defect inspector which can detect a defect smaller than minimum defect size detected by a conventional inspector and particularly can find out the defect near the edge of a pattern sensitively. CONSTITUTION:The pattern defect inspector, a mask 2 forming a pattern is irradiated with light by an illumination lens 4, a pattern image obtained through the mask 2 is image-formed on a light receiving element 6 by an objective lens 5. The pattern defect inspector for inspecting a defect of the pattern on the mask 2 is characterized in that an aperture 31 for modifying a ratio of opening numbers of the illumination lens 4 to the objective lens 5 in response to a kind of the pattern to be measured and a filter for regulating a degree of transmitted of light in an aperture 31 so that a quantity of light received by the light receiving element 6 may be approximately constant even if the ratio of the opening numbers is changed by comparing design data of a pattern with measured data corresponding to the pattern image light-received by the light receiving element 6 are added thereto. |
