Defect detector and defect detecting method

A defects inspecting apparatus, comprising:

• a scanning stage for running into a predetermined direction while mounting an inspection target substrate thereon;
• an illumination optic system for irradiating an illumination spot upon a surface of said inspection target substrate, scanning it into a direction perpendicular to the running direction of said scanning stage;
• a detecting optic system, having an image-forming optic system for condensing reflected/scattered lights, which are generated from said inspection target substrate due to scanning of the illumination spot irradiated within said illumination optic system, and for forming an image thereof, plural numbers of optical fibers receiving lights of the image of reflected/scattered lights, which is formed said image-forming optic system due to scanning of the illumination spot, and thereby for guiding, and photomultiplier tubes receiving an optical image due to the scanning of the illumination spot, guided by said plural numbers of optical fibers, and for converting it into a signal;
• and
• a signal processing system for converting the signal obtained from each of said photomultiplier tubes into a digital signal, and for detecting defects upon basis of said digital signal converted.

A defects inspecting apparatus, comprising:

• a scanning stage for running into a predetermined direction while mounting an inspection target substrate thereon;
• an illumination optic system, having plural numbers of optical modulators for modulating each of plural number of illumination light beams by frequencies, differing from each other, an optical deflector for deflecting the plural numbers of illumination light beams, which are modulate through said plural numbers of optical modulators, into a direction about normal to the running direction of said scanning stage, and a condenser optic system for condensing the plural numbers of illumination light beams, which are deflected by said deflector, upon a surface of said inspection target substrate in a form of plural numbers of illumination spots, thereby for irradiating;
• a detecting optic system, having an image-forming optic system for condensing reflected/scattered lights, which are generated from said inspection target substrate due to scanning of the plural numbers of illumination spot irradiated within said illumination optic system, and for forming an image thereof, a photo-detector for receiving lights of the image of reflected/scattered lights, which is formed said image-forming optic system due to scanning of the plural numbers of illumination spots, and for converting it into a signal;
• and
• a signal processing system, having plural numbers of synchronization detection circuits for extracting components corresponding to frequencies, each being modulated in each of said optical modulators, from the signal converted within the photo-detector of said detection optic system, and for detecting defects upon basis of signals extracted from said plural numbers of synchronization detection circuits.

A defects inspecting method, comprising the followings steps of:

• a first step for irradiating an illumination light beam upon a surface of an inspection target substrate, having circuit patterns thereon, by an illumination optic system, condensing reflected/scattered lights generated from said inspection target substrate irradiated through an objection lens, so as to form an image thereof through an image-forming system, receiving the reflected/scattered lights upon an upper-directed photo-detector, so as to convert into a first image signal, and thereby detecting defects lying on the surface of said inspection target, having the circuit patters thereon, upon basis of said first digital image signal converted;
• and
• a second step for irradiating illumination light beam upon a surface of a transparent film on the inspection target substrate through said illumination:
• optic system at a predetermined inclination angle thereto, condensing reflected/scattered lights generated from said inspection target substrate irradiated from a direction inclined so as to-flatly intersect said illumination direction, by means of the image-forming optic system so as to form an image thereof, receiving said reflected/scattered lights forming the image thereof upon a photo-detector, so as to convert it into a second image signal, and thereby detecting defects lying on the surface of the transparent film on said inspection target substrate upon basis of said second digital image signal converted.

A defects inspecting method, comprising the followings steps of:

• an illumination step for condensing and irradiating plural numbers of illumination light beams, obtained from modulation upon each of the plural numbers of illumination light beams by a frequency, differing from each other, within each of plural numbers of modulators, upon a surface of an inspection target substrate, being deflected by an optical deflector into a direction about normal to a running direction of a scanning stage, in a form of plural numbers of illumination spots;
• a detection step for condensing reflected/scattered lights, which are generated from said inspection target substrate due to scanning of the plural numbers of illumination spots irradiated in said illumination step, so as to form an image through an image-forming system, and receiving lights of the image of reflected/scattered lights due to the scanning of said plural numbers of image-formed illumination spots, upon a photo-detector, thereby converting it into a signal;
• and
• a signal processing step for extracting components corresponding to the frequencies, with which frequency the modulation is made within each of said optical modulators within each of the plural numbers of synchronization detector circuits, from the signal converted by said photo-detector, and thereby detecting defects upon basis of the signal extracted therefrom.