SIGNAL PROCESSING METHOD AND SIGNAL PROCESSING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a signal processing method and a signal processing device which extract a high S/N signal from a high aspect ratio pattern, allowing highly accurate observation and length measurement.SOLUTION: The signal processing method in an embodiment comprises the steps of: scanning a pattern on a substrate with a charged particle beam; detecting secondary charged particles discharged from the substrate with detectors separated or divided into plural regions independently of each other and then outputting what have been detected as signals; and performing a filtering process. The filtering process is increased or reduced in strength depending on a function f(&thetas;) of an angle &thetas; formed by a direction in which the secondary charged particles are incident upon the detection plane and a reference axis which is any direction in plane parallel to the surface of the substrate.