Optical interferometry system for measuring and the method thereof and non-transitory computer readable medium

Abstract

An optical interferometry system and associated methods are provided for interferometric measurement of topography of a sample region having a first direction in which a topographic metric is relatively uniform compared with an orthogonal direction of higher variation. A sensor having a two-dimensional array of pixels receives radiation including interference between reflections from the sample and from a tilted reference mirror. The tilt introduces, at the sensor, a gradient direction of the optical path difference (OPD), such that lines of pixels along the gradient direction correspond to positions of the sample region aligned in the direction of relative constancy. From a single captured image, an interferogram of OPD versus intensity is generated for each such line of pixels.

Images