Charged particle beam apparatus and processor system

Charged particle beam apparatus comprising:

• a first back scattered electron (BSE) detector configured to detect a BSE from a sample;
• and
• a controller, wherein
• in order to determine whether a first peak included in an output signal from the first BSE detector is caused by a BSE or a dark pulse, the controller
• identifies a first pixel in a first frame corresponding to the first peak within a period of a plurality of frames as a period for the output signal from the first BSE detector, and selects a first sub signal including a first peak time corresponding to the first pixel,
• identifies, within the period, a second pixel at a pixel position same as that of the first pixel in a second frame different from the first frame, and selects a second sub signal including a second peak time corresponding to the second pixel,
• determines, when the second sub signal is present where a time difference between the first peak time of the first sub signal and the second peak time of the second sub signal is within a threshold value, that the first peak is caused by the BSE, and
• determines, when the second sub signal is not present where the time difference between the first peak time of the first sub signal and the second peak time of the second sub signal is within the threshold value, that the first peak is caused by the dark pulse.

A processor system comprising:

• one or more processors;
• and
• a memory, wherein
• the processor system
• refers to output signals from a plurality of back scattered electron (BSE) detectors configured to detect a BSE from a sample, and
• in order to determine whether a first peak included in an output signal from a first BSE detector among the plurality of BSE detectors is caused by a BSE or a dark pulse,
• acquires a first peak time of the first peak within a period,
• acquires, within the period, a second peak time of a second peak included in an output signal from a second BSE detector other than the first BSE detector among the plurality of BSE detectors,
• determines, when the second peak is present where a time difference between the first peak time and the second peak time is within a threshold value, that the first peak is caused by the BSE, and
• determines, when the second peak is not present where the time difference between the first peak time and the second peak time is within the threshold value, that the first peak is caused by the dark pulse.