Pattern dimension measurement method and charged particle beam microscope used in same

摘要

In order to provide a pattern dimension measurement method with a small measured error and excellent reproducibility even though defocus occurs and a charged particle beam microscope used in the same, in a method for applying a charged particle beam to a specimen formed with a pattern to measure a pattern dimension from a signal intensity distribution of signal charged particles from the specimen, edge index positions (X1) and (X2) on the right and left of the maximum point of signal intensity corresponding to a pattern edge are calculated by a threshold method, and a pattern edge position (Xe) is found from a mean value between the positions. Thus, it is possible to reduce the influence of defocus on the pattern edge position (Xe).

主权项

1. A pattern dimension measurement method for applying a charged particle beam to a specimen formed with a pattern to measure a pattern dimension from a signal intensity distribution of backscattered charged particles or secondary charged particles generated from the specimen, the method comprising:
calculating a first maximum point of intensity of a waveform at which the signal intensity becomes a maximum intensity at a location corresponding to a first edge of a pattern to be measured; calculating a first edge index position A based on a first threshold, the first edge index position A located to the right of the first maximum point of intensity on the waveform; calculating a first edge index position B based on a second threshold set independently from the first threshold, the first edge index position B located to the left of the first maximum point of intensity on the waveform; and calculating a first edge position of the pattern to be measured based on the first edge index position A and the first edge index position B.