Charged particle beam device

A charged particle beam device comprising:

• a cold field emitter including a tip having a sharpened distal end, a filament connected to the tip, and an auxiliary electrode covering the filament and having an opening from which the tip protrudes;
• an extraction electrode to which an extraction voltage for extracting electrons from the cold field emitter is applied;
• and
• an acceleration electrode to which an acceleration voltage for accelerating the electrons extracted from the cold field emitter is applied;
• a power supply configured to apply an auxiliary voltage Vs to the auxiliary electrode and an extraction voltage V1 to the extraction electrode;
• and
• a current detector coupled to the extraction electrode and configured to, when the tip and the filament are heated, measure a current in the extraction electrode caused by thermionic electrons emitted from the tip in a state in which −5.49V1≤Vs ≤−0.150V1+1.18, and −146/(V1−4.13)+6.40≤Vs≤0.

A charged particle beam device comprising:

• a cold field emitter including a tip having a sharpened distal end, a filament connected to the tip, and an auxiliary electrode covering the filament and having an opening from which the tip protrudes;
• an extraction electrode to which an extraction voltage for extracting electrons from the cold field emitter is applied;
• and
• an acceleration electrode to which an acceleration voltage V0 (kV) for accelerating the electrons extracted from the cold field emitter is applied;
• a power supply configured to apply an auxiliary voltage to the auxiliary electrode and an extraction voltage to the extraction electrode;
• and
• a control unit configured to control an operation of the cold field emitter, the extraction electrode, the acceleration electrode and the power supply, wherein
• the control unit is further configured to:
• control the power supply to apply the auxiliary voltage to be larger than the extraction voltage when the tip and the filament are heated;
• control the power supply to apply the acceleration voltage when the tip and the filament are heated;
• and
• control an observation stop time when the tip and the filament are heated to be V0 (sec) or shorter.

A charged particle beam device comprising:

• a cold field emitter including a tip having a sharpened distal end, a filament connected to the tip, and an auxiliary electrode covering the filament and having an opening from which the tip protrudes;
• an extraction electrode to which an extraction voltage for extracting electrons from the cold field emitter is applied;
• an acceleration electrode to which an acceleration voltage for accelerating the electrons extracted from the cold field emitter is applied;
• a control unit configured to control an operation of the cold field emitter, the extraction electrode and the acceleration electrode;
• a power supply configured to apply a positive voltage to the auxiliary electrode with respect to the tip;
• and
• a current detector coupled to the auxiliary electrode and configured to measure a current in the auxiliary electrode caused by thermionic electrons emitted from the tip and the filament, when the tip and the filament are heated, that are collected by the auxiliary electrode during application of the positive voltage by the power supply,
• wherein the control unit is configured to convert the measured current into a temperature.