Electron optical properties of a new low-energy scanning electron microscope with beam separator

0494372 - ÚPT 2019 RIV CZ eng C - Conference Paper (international conference)
Radlička, Tomáš - Kolařík, V. - Oral, Martin
Electron optical properties of a new low-energy scanning electron microscope with beam separator.
Recent Trends in Charged Particle Optics and Surface Physics Instrumentation. Proceedings of the 16th International Seminar. Brno: Institute of Scientific Instruments The Czech Academy of Sciences, 2018, s. 64-65. ISBN 978-80-87441-23-7.
[Recent Trends in Charged Particle Optics and Surface Physics Instrumentation. Skalský dvůr (CZ), 04.06.2018-08.06.2018]
R&D Projects: GA MŠMT(CZ) LO1212; GA MŠMT ED0017/01/01
Institutional support: RVO:68081731
Keywords : low energy scanning electron microscopy * beam separation * aberrations
OECD category: Electrical and electronic engineering

The low energy scanning electron microscope (SEM) which is currently at the Institute of
Scientific Instruments, suffers from low resolution and suboptimal detections systems. In the cathode lens regime, signal electrons are accelerated by the electric field between the sample and the objective lens, getting collimated. Those with low emission angles get through the bore in the BSE detector into the objective lens and cannot be detected by the available detectors now. The information about the sample provided by these electrons is lost, which limits our microscopy methods.
These two limitations are to be overcome with a new low-energy SEM, which was developed
at Delong Instruments. It consists of a field emission gun with the energy width of 0.8 eV, a magnetic condenser lens, and an electrostatic triode objective lens. The acceleration voltage is 5 kV. The sample stage can be biased at up to -5 kV to provide low landing energy without strong decrease of the resolution – the effect of the cathode lens. A beam separator is placed in front of the deflection system for the detection of the signal electrons that get to the column. In a combination with standard detectors and cathode lens, it allows detecting all
kinds of signal electrons.
Permanent Link: http://hdl.handle.net/11104/0287628