Pattern evaluation method, device therefor, and electron beam device

摘要

An amount of pattern position displacement between observation images acquired by irradiating from two different directions is changed depending on beam deflection for moving an image acquisition position. In a pattern evaluation method that measures astigmatic difference or focus position displacement having a small amount of dose at a high speed using parallax caused by the tilted beam, a correction value obtained in advance by measurement is reflected in an amount of pattern position displacement between observation images obtained by irradiating from at least two different directions and generated in accordance with the amount of beam deflection for moving an image acquisition position. A processing unit calculates an amount of correction of an amount of pattern position displacement depending on beam deflection of a beam deflecting unit for moving an image acquisition position on the sample at a high speed.

主权项

1. A minute pattern evaluation method that uses a charged particle beam of a charged particle beam device including a charged particle optical system and a processing unit, the method comprising the steps of:
irradiating the sample with the charged particle beam in a direction in accordance with an optical system condition for irradiating a charged particle beam and acquiring an image; irradiating the sample with the charged particle beam in another direction in accordance with the optical system condition for irradiating a charged particle beam and acquiring another image; comparing the image and the another image to measure a pattern position displacement amount between the images, and correcting, by the processing unit, the pattern position displacement amount based on a correction amount, wherein the correction amount is calculated based on the beam deflection of the charged particle beam that moves an image acquisition position on the sample.