| 摘要 |
In a charged particle beam device, such as an electron microscope, a beam generating means (101) generates a focussed charged particle beam e- that is incident on a specimen (104) in a specimen chamber (102) which holds the specimen in a gaseous environment. A pressure limiting aperture (144) provides partial gaseous isolation of the specimen chamber from the beam generating means, and is located in a lens (114) of the latter. The device includes a conduit, such as an intermediate chamber (132) in the lens, through which, in use, gas is supplied to set up a flow of gas from the region of the lens towards the specimen, thereby to prevent material released from the specimen from impinging on the pressure limiting aperture, to prevent contamination of the latter. The device can be used in a method of scanning a specimen with a charged particle beam, for example in a method of electron microscopy. |
