Asymmetrical detector design and methodology

摘要

A charged particle detection device has an active portion for configured to produce a signal in response secondary charged particles emitted from a sample landing on the active portion. The active portion is shaped to accommodate an expected asymmetric pattern of the secondary charged particles at a detector. This abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

主权项

1. A charged particle detection device, comprising:
a detector having an active portion and an inactive portion formed on a surface of a substrate, the surface being divided into the active portion and the inactive portion, whereby the active portion and the inactive portion make up an entirety of the surface of the substrate, wherein only the active portion is configured to produce a signal in response to secondary charged particles emitted from a sample landing on the active portion, wherein the substrate is symmetric with respect to an axis through a central aperture and wherein the active portion is asymmetric with respect to the axis to, accommodate an estimated axially asymmetrical distribution of the secondary particles at the detector with respect to a beam axis of a charged particle beam optical system.