Tao-Yi Fu

TL;DR: In this paper, a transmissive substrate is illuminated by a laser through an optical system comprised of a laser scanning system, individual transmitted and reflected light collection optics and detectors collect and generate signals representative of the light transmitted by the substrate as the substrate is scanned repeatedly in one axis in a serpentine pattern.

TL;DR: In this article, an automated photomask inspection apparatus including an XY state (12) for transporting a substrate (14) under test in a serpentine path in an XY plane, an optical system (16) comprising a laser (30), a transmission light detector (34), a reflected light detector(36), optical elements defining reference beam paths and illuminating beam paths between the laser, the substrate and the detectors and an acousto-optical beam scanner (40, 42) for reciprocatingly scanning the illuminating and reference beams relative to the substrate surface, and an electronic control

TL;DR: In this paper, an illumination system for generating a light beam, passing that light beam through a fixed optical path and making it almost practically perpendicularly incident to the upper surface of an inspection substrate, transmitted light detector 34 for collecting and detecting the transmitted beams by adjusting them so as to be coaxial to that optical path, reflected light detector 36 for similarly collecting and detected reflected light, comparator for providing a compare value by mutually comparing respective electric signals, and processor for separately providing the expected value of that compare value and discriminating the coincidence between the comparison value and that expected value.

TL;DR: In this article, the authors present a method for source multiplexing illumination for mask inspection at nodes below the 22 nm, where the reflected and scattered light from the mask image is then processed for defect information.

TL;DR: In this article, the authors proposed an automatic photomask-inspecting apparatus consisting of a lighting system that generates light beams, allowing the light beams to pass a fixed light path to be incident to the surface on an inspection substrate substantially at a right angle, a transmission light detector 34 for making an adjustment so that it is coaxial to the light path and gathers and detects transmission light, a reflection light detector 36 for gathering reflection light similarly for detection and a comparator for providing a comparison value by comparing each electric signal, and a processor for judging the coincidence between a comparison