DETECTION OF CONTAMINATION, DEVICE FOR IT AND SEMICONDUCTOR MANUFACTURING LINE

• Main Authors: NOGUCHI MINORU, KENBO YUKIO
• Format: Patent
• Language: English
• Published: 16.12.1991
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

PURPOSE:To make it possible to detect easily the degree of contamination of a substrate and the presence or absence of foreign substances by a method wherein when the whole surface of the substrate is scanned with spot light, scattered light from a spot position on the substrate is detected while the generation of an unnecessary Rayleigh scattering is suppressed. CONSTITUTION:A sample 3 subjected to heating treatment is next placed on a mount stage 205 and thereafter, the height of the surface of the sample 3 is adjusted so as to coincide with the focus surface of a scattered light detection system 223. After that, while the sample 3 is rotated by a stage 204 and moreover, while the sample 3 is moved by an X stage 202 in a direction X, the whole surface of the sample is scanned with a laser beam spot. In the case foreign substances or contamination exist at a certain scanning position, a laser beam scattered by them is detected by a detector 209 via an objective lens 208 and with this detection it can be decided that the foreign substances or the contamination exist. As a vacuum chamber 201 is exhausted so as to bring its interior in a vacuum state prior to the detection of the contamination, the scattered light of the laser beam can be detected by the detector 209 in a large S/N ratio in a state that the generation of an unnecessary Rayleigh scattering is suppressed as much as possible.