Method and apparatus for inspecting foreign particle defects

An for inspecting a foreign particle defect, comprising:

• an illuminator which irradiates a surface of a sample with an illuminating beam;
• a detector which collects through an objective lens scattered reflected light from the surface of the sample as illuminated by the illuminator and detects the collected light with a detecting device;
• and
• a signal processor which processes a signal obtained as a result of the detection of the scattered reflected light by the detecting device of the detector so as to detect a foreign particle defect on the surface of the sample,
• wherein the detector includes a converging optical system which collects the scattered reflected light from the surface of the sample, and an aberration corrector which corrects an aberration of the converging optical system,
• wherein the illuminating beam emitted from the illuminator toward the surface of the sample is formed in a shape long in a direction, and emitted from a direction oblique to the surface of the sample, and
• wherein the converging optical system of the detector further includes an image forming magnification changer which changes an image forming magnification of the converging optical system while a position of the objective lens relatively to the detecting device is fixed.

A method for inspecting a foreign particle defect, comprising the steps of:

• irradiating a surface of a sample with an illuminating beam;
• collecting, with a converging optical system, scattered reflected light from the irradiated sample, and detecting at a desired magnification an image of the scattered reflected light as collected;
• and
• processing a signal obtained as a result of the detection of the scattered reflected light, and detecting a foreign particle defect on the surface of the sample,
• wherein the image of the scattered reflected light from the surface of the sample is detected by correcting an aberration of the converging optical system according to the desired magnification,
• wherein the irradiating step comprises forming the illuminating beam in a shape long in a direction, and emitting the illuminating beam from a direction oblique to the surface of the sample, and
• wherein the irradiating step comprises irradiating the surface of the sample with an angle from which the illuminating beam is emitted being switched between a high angle and a low angle.