Substrate thickness measurement using color metrology

摘要

A metrology system for obtaining a measurement representative of a layer thickness of a substrate includes a camera arranged to capture a color image of at least a portion of the substrate. The controller receives a color image from the camera, stores a predetermined path in at least a two-dimensional coordinate space including the first color channel and the second color channel, and represents the thickness as a function of a position on the predetermined path. Save the function that provides the value, determine the coordinates of the pixel in the coordinate space from the color data of the color image of the pixel, determine the position of the point on the predetermined path closest to the coordinates of the pixel, and A value representing the thickness is calculated from the function and position of the point on the path. [Selection] Figure 7