Ion beam device

An ion beam device configured to irradiate a sample with an ion beam to observe or process the sample, the ion beam device comprising:

• an emitter tip having a needle-shaped end;
• an extraction electrode arranged to face the emitter tip and having an opening at a position away from the emitter tip;
• a gas supply source configured to supply a gas to the vicinity of the emitter tip;
• a voltage source configured to apply a voltage between the emitter tip and the extraction electrode, thereby irradiating the sample with an ion beam from the emitter tip;
• a detector configured to detect a secondary electron or a secondary ion emitted from the sample by irradiating the sample with the second ion beam, and
• a computer configured to detect a charged particle generated from the sample by irradiating the sample with the ion beam, thereby generating an observation image of the sample, wherein
• the gas supply source is configured to supply a gas that contains a first element having a first mass number and a second element having a second mass number larger than the first mass number,
• the voltage source is configured to perform a first mode of applying a first voltage to irradiate the sample with a first ion beam generated by ionizing the first element from the emitter tip, and a second mode of processing the sample in a thickness direction by applying a second voltage to irradiate the sample with a second ion beam generated by ionizing the second element from the emitter tip,
• the computer is configured to obtain a first observation image of a first shape formed in a first region of the sample,
• the voltage source is configured to perform the second mode when the emitter tip irradiates a second region of the sample with an ion beam after the computer obtains the first observation image, thereby forming a first hole reaching a first depth inside the sample in a second region,
• the voltage source is configured to perform the first mode on the second region after the first hole is formed,
• the computer is configured to obtain a second observation image of a second shape formed in the second region after the first hole is formed by the voltage source performing the first mode on the second region,
• the computer is configured to compare the first observation image and the second observation image, thereby obtaining a relative positional relation between the first shape and the second shape,
• the computer is configured to compare a first signal pattern of the secondary electron or the secondary ion detected by the detector and a second signal pattern of the secondary electron or secondary ion emitted from a known structure in the sample,
• the second signal pattern comprising a plurality of N peaks, each peak corresponding to a different conductor layer of a plurality of N layers of the sample, and
• the computer is configured to terminate the second mode when the first signal pattern and the second signal pattern match a predetermined termination condition indicating a depth reaching the Nth layer of the sample.