Patent ID: 7973920
Filing Date: 2011-07-05
Classification: G01N,H01L

Abstract:
1. A defect inspection apparatus comprising: a stage that is caused to travel after a substrate to be inspected is rested thereon, the substrate having a circuit pattern formed thereon; an irradiation optical system that a beam flux emitted from a laser light source is guided to a first or second optical path, focuses the beam flux that has been guided to the first or second optical path into a slit-shaped beam being formed up by fluxes of light that are substantially parallel in a longitudinal direction, from a direction having a required inclination with respect to the surface of the substrate to be inspected, so as to irradiate the beam flux onto the surface of the substrate to be inspected; a detection optical system that uses an objective lens to converge reflected light obtained from contamination or defects present on the substrate that has been irradiated with the slit-shaped beam, and uses an image sensor to receive the reflected/scattered light that has been converged, converts the received light into a signal, and detects the signal; and an image processor that extracts, on the basis of the signal that has been detected by the image sensor of the detection optical system, a signal indicative of a defect; wherein the irradiation optical system includes: a mirror that reflects the beam flux that has been guided to the first or second optical path; and a cylindrical lens and an inclined mirror each for focusing the beam flux that has been reflected onto the mirror onto the substrate to be inspected, as the slit-shaped beam, and wherein the cylindrical lens is disposed so as to obtain a distance between an incidence surface or emitting surface thereof and the slit-shaped beam upon the substrate to be inspected to be equal to a focal distance of the cylindrical lens.