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A high-precision angular accelerometer based on molecular–electronic transfer (MET) technology with a high dynamic range and a low level of self-noise has been developed. Its difference from the analogues is in the use of liquid (electrolyte) as the inertial mass and the use of negative feedback based on the magnetohydrodynamic effect. This article reports on the development of the angular molecular–electronic accelerometer with a magnetohydrodynamic cell for the creation of negative feedback, and the optimization of electronics for the creation of a feedback signal. The main characteristics of the angular accelerometer, such as amplitude–frequency characteristics, self-noise and Allan variance were experimentally measured. The obtained output parameters were compared to its analogues and it showed perspectives for further development in this field.

The authors report the development of a simulation tool with unique capabilities to comprehensively model a scanning electron microscope (SEM) signal. This includes electron scattering, charging, and detector settings, as well as modeling of the local and global electromagnetic fields and electron trajectories in these fields. Experimental and simulated results were compared for SEM imaging of carbon nanofibers embedded into bulk material in the presence of significant charging as well as for samples with applied potential on metal electrodes. The effect of the potentials applied to electrodes on the secondary emission was studied; the resulting SEM images were simulated. The image contrast depends strongly on the sign and the value of the potential. SEM imaging of nanofibers embedded into silicon dioxide resulted in the considerable change in the apparent dimensions of the fibers as well as tone reversal when the beam voltage was varied. The results of the simulations are in agreement with experimental results.

In semiconductor manufacturing, accurate measurement of shapes and sizes of fabricated features is required. These measurements are carried out using critical dimension scanning electron microscope (CD-SEM). Positions of edges are often unclear because of charging. Depending on the SEM setup and the pattern under measurement, the effect of charging varies. The influence of measurement conditions can be simulated and optimized. A Monte Carlo electron beam simulation tool was developed, which takes into account electron scattering and charging. CD-SEM imaging of silicon dioxide lines on silicon was studied. In the experiment, changes in the beam voltage were found to result in contrast tone reversal. The same effect was also found in simulations considering charging. The time dependence of contrast variation was studied. A good agreement between simulation and measurement was found. The simulation software proved reliable in predicting SEM images, which makes it an important instrument to optimize settings of electron beam systems.