OPTICAL INSPECTION TOOLS INCLUDING LENS UNIT WITH AT LEAST A PAIR OF BEAM PATHS THEREIN AND METHODS OF DETECTING SURFACE DEFECTS OF A SUBSTRATE USING THE SAME

• Main Authors: JUN, CHUNG SAM, KIM, SANG HEE, LEE, DONG CHUN, KIM, IK CHUL, KIM, JONG AN
• Format: Patent
• Language: English
• Published: 02.01.2007
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

An optical inspection tools having a lens unit with at least one pair of beam paths therein and a method for detecting surface defects of a substrate using the same are provided to improve resolution of optical testing equipments by employing a first beam path and a second beam path in the lens unit having a lens module. A substrate(55) is loaded on a chuck(53). A lens unit(60) is located on an upper portion of the chuck and has at least a pair of beam paths(60a,60b). The beam paths provide directionality of a light. A camera(61) is installed on the lens unit to convert the light passing through the lens unit into an image. The pair of beam paths include at least one first beam path and at least one second beam path that are symmetrical to each other with respect to a vertical central shaft of the lens unit. The beam paths are empty spaces passing through a part of at least one of plural lenses.