Patent ID: 7397555
Filing Date: 2008-07-08
Classification: G01N

Abstract:
1. A system for inspecting a substrate comprising: a camera having a centerline, wherein the centerline is oriented toward a field of view, wherein the field of view encompasses at least a first portion of a first surface of the substrate; a light source oriented toward the field of view at a first angle β relative to the first surface of the substrate, wherein the first angle β orients the light source to emit light impinging the first surface within the field of view, the light source is further oriented at a second angle δ relative to the centerline, the second angle δ being between about 90 degrees and less than about 180 degrees, the centerline intersects the first surface at a third angle α, the third angle α being between about 20 degrees and about 33 degrees, the first angle β is selected to minimize a direct reflection of light from the first portion of the first surface to the camera, wherein the system for inspecting the substrate is included in a process chamber for applying a manufacturing process to the substrate, the manufacturing process being in addition to the inspection process; and a controller coupled to the system for inspecting the substrate, wherein the light source includes a plurality of point light sources, wherein each one of the point light sources has a corresponding selected wavelength of light output and wherein the control system includes a logic for selecting one of the plurality of light sources having the selected wavelength of light output and logic for selecting one of a plurality of intensity levels, wherein the selected wavelength of light output and the selected intensity level corresponds to the manufacturing process applied to the substrate.