Scanning electron microscope
AssigneeDirector-General of Agency of Industrial Science and Technology
InventorsMasaki Kitagawa, Akira Ohtomo, Teruo Fujimoto
Life of this patent
Estimating the term…
Abstract
A scanning electron microscope includes a heater coil which is arranged around a sample, an electron beam which is radiated when the sample is heated, and a secondary electron generated from the sample which is attracted to a photo multiplier. In this electron microscope, a shield plate is provided having an extracting hole for extracting the secondary electron outside of the heat coil in such a manner that the extracting hole is aligned with a light axis of the electron beam. The shield plate is connected to a power source which supplies a variable voltage so that a desired voltage can be applied to the shield plate so as to shield thermal electrons.
Claims5
An electron microscope comprising:
- a heater coil arranged around a sample for heating said sample,
- an electron source for radiating an electron beam when said sample is heated,
- a photo multiplier tube to which secondary electrons generated from said sample are attracted,
- a power source for supplying a variable voltage, and
- a shield member having an extracting hole for extracting said secondary electrons outside of said heater coil in such a manner that said extracting hole is aligned with a light axis of said electron beam, said shield member being connected to said power source which supplies a variable voltage so as to apply a desired voltage to said shield member,
- wherein said heater coil is wound in such a manner that a heater coil on the left of the axis of said electron beam and a heater coil on the right of the axis of said electron beam are wound in an inverse direction.
Dependencies are inferred from the claim text.