TEST PIECE CHAMBER DIFFERENTIAL EXHAUST APPARATUS

PROBLEM TO BE SOLVED: To greatly improve a service life of a detector detecting a secondary electron or a reflection electron even when vacuum in a test piece chamber is made low by effectively making use of a differential exhaust function in a small exhausting system regarding a test piece chamber differential exhaust apparatus of a scanning type electron microscope producing an image by detecting the discharged secondary electrons or the reflection electrodes by carrying out planar scanning while having a test piece irradiated by an electron beam which is narrow-focused. SOLUTION: The test piece differential exhaust apparatus is composed of: a plurality of steps of orifices for exhausting of the differential provided between the test piece chamber for placing the test piece and a detector for detecting the secondary electrons or the reflected reflection electrons discharged by having the test piece placed in the test piece chamber irradiated by the electron beam; and an exhausting system directly connected to a part of a plurality of orifices. COPYRIGHT: (C)2007,JPO&INPIT