CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of Japanese Patent Application No. 2020-047395, filed Mar. 18, 2020, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field

The present disclosure relates to a charged particle beam apparatus.

2. Description of the Related Art

A charged particle beam apparatus that changes an incidence angle of a charged particle beam by rotating a sample around multiple rotating axes in order to process or observe the sample in three dimensions through irradiation with the charged particle beam, such as a focused ion beam, an electron beam, or the like, is known in the related art (for example, see Patent Document 1).

Document of Related Art

(Patent Document 1) Japanese Patent Application Publication No. 2016-72089

SUMMARY OF THE INVENTION

However, in the above-described charged particle beam apparatus, a center of rotation for rotation around each rotating axis may change due to, for example, mechanical precision, intersection, and the like of rotating units on the respective rotating axes. The change of the center of rotation causes a change in an irradiation position of a charged particle beam, so there is a concern that a processing position or an observation position desired at the sample may change.

The present disclosure is directed to providing a charged particle beam apparatus that is capable of limiting a change in an irradiation position of a charged particle beam by properly correcting a positional deviation caused by rotation of a sample.

According to the present disclosure, there is provided a charged particle beam apparatus including: a charged particle beam column irradiating a sample with a charged particle beam; a sample holder having a securing member for fixing the sample; a stage supporting the sample holder; a securing member rotating unit rotating the securing member around a first rotational axis and a second rotational axis parallel to a direction perpendicular to the first rotational axis, independently of the stage; a stage driving unit translating the stage three dimensionally together with the sample holder and rotating the stage together with the sample holder around a third rotational axis; and a processing device correcting an irradiation position of the charged particle beam on the sample by acquiring a correction value for correcting a change in a position of a center of rotation for rotation around at least one among the first rotational axis, the second rotational axis, and the third rotational axis, and translating the stage according to the correction value, thereby correcting an irradiation position of the charged particle beam on the sample.

In the above configuration, with positions of the center of rotation before and after rotation as a pre-rotation position and a post-rotation position, respectively, around at least one among the first rotational axis, the second rotational axis, and the third rotational axis, the correction value may be acquired by synthesizing, a vector of the pre-rotation position and a vector of the post-rotation position with respect to each reference position of rotation of the first rotational axis, the second rotational axis, and the third rotational axis.

In the above configuration, the correction value may be acquired based on the center of rotation changes its position on a predetermined closed curve.

In the above configuration, the closed curve may be an ellipse.

In the above configuration, the charged particle beam apparatus may further include a storage storing table data that shows a corresponding relationship between the correction value and an angle of rotation around each of the first rotational axis, the second rotational axis, and the third rotational axis, wherein the processing device may acquire the correction value from the table data.

In the above configuration, in addition to correction of the irradiation position for rotation around at least one among the first rotational axis, the second rotational axis, and the third rotational axis, the processing device may correct a geometric positional deviation of the sample with respect to an irradiation reference position set relative to the securing member.

In the above configuration, when the rotation around at least one among the first rotational axis, the second rotational axis, and the third rotational axis is performed during irradiation of the sample with the charged particle beam, the processing device corrects the irradiation position after the rotation is performed.

In the above configuration, in addition to the translation and the rotation around the third rotational axis, the stage driving unit may tilt the stage, together with the sample holder, around a tilt axis in an eucentric manner so that the position of a center of rotation is not changed.

According to the present disclosure, a processing device for correcting a change in a position of a center of rotation of a rotating axis for rotation of a sample is provided, thereby limiting a change in an irradiation position of a charged particle beam.

