Apparatus and method for inspecting pattern

An apparatus for inspecting defects, comprising:

• a table on which a specimen to be inspected is mounted, the table being movable in a plane;
• an ultraviolet light source for emitting ultraviolet light;
• an illuminating unit for illuminating the specimen mounted on the table with light emitted from the ultraviolet light source;
• a detecting unit for forming an image of the specimen illuminated by the illuminating unit and detecting the image with an image sensor;
• and
• an image processing unit for processing the image detected by the image sensor and outputting information about defects detected on the specimen;
• wherein the illuminating unit is disposed in a clean environment supplied with clean gas, and
• wherein a space between the specimen and the objective lens is maintained at a negative pressure.