US 7,223,983 B2 · Charged particle beam column

Abstract

The present invention provides a charged particle beam column that does not cause displacement of an image or degradation of a resolution of images when a charged particle beam is tilted at a large angle. In the charged particle beam column including an aberration corrector, a deflector is used to control the direction of incidence of the charged particle beam on a second condenser lens but the object point of a condenser lens is not shifted. Consequently, the converging charged particle beam is tilted at a large angle with respect to the surface of a specimen without the necessity of shifting the object point of an objective lens lying on the optical axis of the charged particle beam column. At this time, the aberration corrector prevents a shift of an image or degradation of a resolution derived from the tilt of the charged particle beam.

Claims11

Dependent claims

A charged particle beam column comprising:

a charged particle source that supplies a charged particle beam;
one or more condenser lenses that control the convergence angle of the charged particle beam radiated from the charged particle source and the convergent position thereof;
an objective lens that converges the charged particle beam on the surface of a specimen;
an aberration corrector that compensates both or either of chromatic aberration and spherical aberration caused by the condenser lenses and the objective lens;
a deflector that controls the direction of incidence of the charged particle beam on the aberration corrector;
and
a scanning means for scanning the surface of the specimen with the charged particle beam, wherein:
the tilted charged particle beam is converged on the surface of the specimen at a predetermined angle without the necessity of shifting the object point of the objective lens lying on the optical axis of the charged particle beam column.

5 more elements

A charged particle beam column comprising:

a charged particle source that supplies a charged particle beam;
one or more condenser lenses that control the convergence angle of the charged particle beam radiated from the charged particle source and the convergent position thereof;
an objective lens that converges the charged particle beam on the surface of a specimen;
an aberration corrector that compensates both or either of chromatic aberration and spherical aberration caused by the condenser lenses and the objective lens;
a movable aperture that limits the incident position of the charged particle beam entering the aberration corrector and the quantity of the incident charged particle beam;
and
a scanning means for scanning the surface of the specimen with the charged particle beam, wherein:
a control means for controlling the movable aperture so as to modify the direction of emission from the object point of the objective lens without shifting the object point of the objective lens lying on the optical axis, and thus routing the charged particle beam to the objective lens is included in order to converge the tilted charged particle beam on the surface of the specimen at a predetermined angle.

5 more elements

A charged particle beam column comprising:

a charged particle source that supplies a charged particle beam;
one or more condenser lenses that control the convergence angle of the charged particle beam radiated from the charged particle source and the convergent position thereof;
an objective lens that converges the charged particle beam on the surface of a specimen;
an aberration corrector that compensates both or either of chromatic aberration and spherical aberration caused by the condenser lenses and the objective lens;
a deflector that controls the direction of incidence of the charged particle beam on the aberration corrector;
a movable aperture located near and ahead of the deflector;
and
a scanning means for scanning the surface of the specimen with the charged particle beam, wherein:
the charged particle beam is tilted at an angle of 10° or more with respect to the optical axis of the charged particle beam column but the object point of the objective lens lying on the optical axis is not shifted;
and
the aberration corrector compensates aberration derived from the tilt of the charged particle beam.

8 more elements

Dependencies are inferred from the claim text.

Charged particle beam column

Life of this patent

Charged particle beam column

Life of this patent

Abstract

Claims11