METHOD FOR DETECTING SURFACE DEFECTS ON A SUBSTRATE AND DEVICE USING SAID METHOD

摘要

Method for detecting surface defects on a substrate and device using said method. This invention relates to a method for detecting surface defects, such as =slip line= type defects, on a substrate (2) designed to be used in electronics, optoelectronics or analogue, remarkable in that it comprises at least the following steps: -projection of a pattern composed of an alternation of light fringes and dark bands onto the substrate (2), so as to generate fringes reflected by the surface of the substrate (2), -relative displacement of the pattern and the substrate (2) along at least one direction, so as to displace the fringes of the pattern on the substrate (2), -acquisition of a sequence of at least three images of the pattern reflected by the substrate (2) by a sensor (8), the images corresponding to displacement of the fringes of the pattern, -determination of the gradient of the surface of the substrate (2) using displacements of fringes of the pattern, and -determination of the presence of a surface defect on the substrate (2) using variations in the gradient of the surface of the substrate (2). Another purpose of the invention relates to a device using said method.