SU506084A1 - Raster mirror electron microscope - Google Patents

Description

one

This invention relates to electron microscopy.

Raster mirror electron microscopes (REEM) are known, which contain an electron beam braking and focusing system made in the form of a multielectrode immersion objective, one of the electrodes of which is the sample under study, a magnetic prism, a collector with a scintillator and a contrast aperture.

However, the known REEMs have a low signal-to-noise ratio and do not allow obtaining quantitative information about the distribution of electric and magnetic microfields on the surface of the sample under study.

In the proposed REEM, these defects are eliminated due to the fact that the microscope is equipped with a power analyzer installed between the scintillator and the magnetic prism along the secondary beam and made in the form of a three-electrode lens filter with adjustable voltage on the middle electrode, and the inlet of the power analyzer serves as a contrast aperture.

The drawing shows the scheme proposed REM.

A REEM contains an electron tip 1, {) b-1) ectvip 10 lipza 2, scintillator 3 with C15CT () pr () house, three-electrode granddaughter lens 4, magnetic prism 5, anodia diaphragm 6 and modulator 7 of the immersion objective.

REMEM works in the following way. The electron beam after passing through a deflecting prism 5 enters the field of an immersion lens, the focal distance of which is chosen (for example, by changing the voltage t / m) so that the nook falls perpendicular to the surface of

Sample 8. A multi-electrode lens ensures normal beam incidence but the entire field of view, which significantly improves the resolution of a REEM on the edge of the field of view due to the absence of tangential velocity components when approaching the sample and reflecting the primary beam from it. The specularly reflected or secondary electrons are focused on the inlet orifice — the lens aperture 4, and after passing through it, drop onto the scintillator 3 with the light guide. Further, the spgnal is amplified by a PMT and a SEM video amplifier.

Lens filter works as follows. When analyzing the secondary electrons (when the primary beam bombards the sample under test with low energy), an adjustable neutral delay Us is applied to the middle electrode of the filter lens, and the local potential of the sample area under investigation is measured by the shift of the removed delay curves. If the middle electrode is grounded, the potential distribution or electric (magnetic) microfields can be measured by image contrast (from the curves of current density distribution of reflected electrons), and the image contrast forms: Ti: i due to the shift of the reflected beam crossover as well as in the emission microscope.

Claims (1)

Invention Formula A scanning electron mirror microscope containing an electron beam braking and focusing system made in the form of a multi-electrode immersion lens, one of the electrodes of which is a test sample, a magnetic prism, a collector with a scintillator, and a contrast diaphragm, characterized in that, in order to improve the signal / ratio, to obtain quantitative information on the distribution of electric and magnetic micronols on the sample surface it is equipped with a power analyzer installed between a scintillator and a magnetic prism along the secondary beam, made in the form of a three-electrode filter lens with adjustable voltage on the middle electrode, and the inlet of the energy analyzer serves as a contrasting diaphragm.