Patent ID: 8294097

Claim:
A charged particle beam device, comprising: a charged particle source; a charged particle optical system which includes a lens, and focuses a primary charged particle beam emitted from the charged particle source to scan a sample therewith; a detector which detects a signal particle which is generated from the sample by the scanning with the primary charged particle beam; and a control unit which controls the lens, the charged particle beam device acquiring a sample image by using a signal of the detector means, wherein: the charged particle beam device further comprises a sample chamber controlled to a low vacuum (1 Pa to 3,000 Pa); and the detector includes: a control unit which includes a positive electrode in which +300 to +500 V is applied to at least one electrode, detects light having image information by means of a light guide (optical waveguide) disposed in a vicinity of the positive electrode, converts and amplifies the light into photoelectrons by means of a photomultiplier tube coupled to the light guide, and then forms an image to thereby enable observation; and a control unit which detects, as a current signal, an ion current having image information from another electrode having a potential different from that of the electrode, and forms an image.