Scanning electron microscope

摘要

With a scanning electron microscope (SEM) adopting a commonly available exhaust system such as a turbo-molecular pump, an ion pump, or a rotary pump, and so forth, there is realized an apparatus capable of safely executing observation, or adsorption of a target substance that is high in rarity. Further, there is realized a safe SEM low in the risk of an electrical discharge by providing the apparatus with a probe, a means for replacing an atmosphere in a specimen chamber, with a predetermined gas, and a means for forming an image by detection of an ion current, and detection of an absorption current. Further, there is provided a means for controlling the polarity of a voltage applied to the probe. Still further, there is provided a control means for controlling a value of the voltage applied to the probe according to a degree of vacuum.

主权项

1. A scanning electron microscope provided with a specimen chamber for storing a target substance, and a vacuum pump for evacuating the specimen chamber into a vacuum, the scanning electron microscope comprising:
a gas introduction pipe for introducing a gas into the specimen chamber evacuated into a vacuum by use of the vacuum pump; a electron optical tube for detecting an ion current, the ion current being generated by amplifying a secondary electron, or a reflection electron, emitted from the target substance, upon irradiation of the target substance in the specimen chamber with a primary electron beam, in the gas; a probe for adsorbing the target substance; a probe-movable mechanism for causing the probe to be moved inside the specimen chamber; and a power supply unit for applying a voltage for generating an electrostatic adsorption force to the probe; wherein the power supply unit applies the voltage for electrostatically adsorbing the target without an electrical discharge against a degree of vacuum in the specimen chamber.