Analysis Of Gas Flow In The New System Of Apertures In The Secondary Electron Scintillation Detector For ESEM

0384060 - ÚPT 2013 RIV US eng J - Journal Article
Maxa, J. - Neděla, Vilém - Jirák, J.
Analysis Of Gas Flow In The New System Of Apertures In The Secondary Electron Scintillation Detector For ESEM.
Microscopy and Microanalysis. Roč. 18, Suppl. 2 (2012), s. 1264-1265. ISSN 1431-9276. E-ISSN 1435-8115
R&D Projects: GA ČR GAP102/10/1410; GA MŠMT EE.2.3.20.0103
Institutional support: RVO:68081731
Keywords : environmental scanning electron microscope * scintillation detector * secondary electrons
Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Impact factor: 2.495, year: 2012

he scintillation detector of secondary electrons for Environmental scanning electron microscope (ESEM) is designed to be able to detect secondary electrons (SE) with high efficiency at gas pressure range from 0,01 Pa to 1000 Pa in the specimen chamber of ESEM. In the detector, see Fig. 1, the scintillator is placed in a separately pumped chamber, which is separated from the specimen chamber by two pressure-limiting apertures. The apertures reduce the gas flow through the detector and due to the accelerating voltage up to 10 kV on the scintillator prevent electric discharge (the gas pressure in the scintillator chamber must not exceed 5 Pa). The voltage on the apertures (on order of hundreds of volts) creates an electrostatic field, which helps the detected SE to pass towards the scintillator. The size of the aperture holes, their distance, the shape of the space between them as well as the speed of vacuum pump crucially influence the gas flow character and attainable decrease of gas pressure in the detector.
Permanent Link: http://hdl.handle.net/11104/0213815