Method of characterizing a detection path of a charged particle beam and a charged particle mirror

A charged particle mirror configured for characterizing a charged particle beam system according to a method of characterizing a detection path in a charged particle beam system having a primary charged particle beam, the method comprising:

• positioning a charged particle mirror having a known curved equipotential surface on a sample stage of the charged particle beam system;
• varying a reflection angle of the primary charged particle beam at the known curved equipotential surface by varying a relative mirror position of the charged particle mirror, the known curved equipotential surface being at a distance to a surface of the charged particle mirror;
• and
• recording a plurality of detector signals of at least one detector of the charged particle beam system for a plurality of relative mirror positions;
• wherein varying the relative mirror position of the charged particle mirror comprises varying at least one of a mirror position of the charged particle mirror and a primary charged particle beam position with respect to each other in at least one dimension.

A charged particle mirror, comprising:

• a substrate;
• a mirror element having a pillar recessed with respect to a surface of the substrate;
• wherein the pillar comprises one of:
• a conductive connection configured for connecting the pillar to a voltage source;
• a conductive element being configured for generating a curved equipotential surface when a voltage is applied;
• and wherein the pillar is rotationally symmetric.