We have constructed an eddy current shielded room from high-conductivity aluminum sheets, 1.88 cm thick. A series of measurements designed to test the performance of the room has been carried out. The results of the measurements have been compared with theoretical predictions and also with the results from similar rooms reported in the literature. In some respects the agreement is good while in other respects considerable discrepancy exists. The response time of the room to a uniform field was found to be in good agreement with theory, whereas the response to a nonuniform field was found to be much worse. We also found that the room does not shield the vertical field component as well as the horizontal components. We give the reason for this and suggest a possible solution.

This paper investigates field emission behavior from the surface of a tip that was prepared from polymer graphite nanocomposites subjected to electrochemical etching. The essence of the tip preparation is to create a membrane of etchant over an electrode metal ring. The graphite rod acts here as an anode and immerses into the membrane filled with alkali etchant. After the etching process, the tip is cleaned and analyzed by Raman spectroscopy, investigating the chemical composition of the tip. The topography information is obtained using the Scanning Electron Microscopy and by Field Emission Microscopy. The evaluation and characterization of field emission behavior is performed at ultra-high vacuum conditions using the Field Emission Microscopy where both the field electron emission pattern projected on the screen and current–voltage characteristics are recorded. The latter is an essential tool that is used both for the imaging of the tip surfaces by electrons that are emitted toward the screen, as well as a tool for measuring current–voltage characteristics that are the input to test field emission orthodoxy.

A fast position-sensitive detector was designed for the angle- and energy-selective detection of signal electrons in the scanning low energy electron microscope (SLEEM), based on a thinned back-side directly electron-bombarded charged-coupled device (CCD) sensor (EBCCD). The principle of the SLEEM operation and the motivation for the development of the detector are explained. The electronics of the detector is described as well as the methods used for the measurement of the electron-bombarded gain and of the dark signal. The EBCCD gain of 565 for electron energy 5 keV and dynamic range 59 dB for short integration time up to 10 ms at room temperature were obtained. The energy dependence of EBCCD gain and the detection efficiency are presented for electron energy between 2 and 5 keV, and the integration time dependence of the output signals under dark conditions is given for integration time from 1 to 500 ms.

The use of a thinned back-side illuminated charge coupled device chip as two-dimensional sensor working in direct electron bombarded mode at optimum energy of the incident signal electrons is demonstrated and the measurements of the modulation transfer function (MTF) and detective quantum efficiency (DQE) are described. The MTF was measured for energy of electrons 4keV using an edge projection method and a stripe projection method. The decrease of the MTF for a maximum spatial frequency of 20.8cycles∕mm, corresponding to the pixel size 24×24μm, is 0.75≈−2.5dB, and it is approximately the same for both horizontal and vertical directions. DQE was measured using an empty image and the mixing factor method. Empty images were acquired for energies of electrons from 2to5keV and for various doses, ranging from nearly dark image to a nearly saturated one. DQE increases with increasing energy of bombarded electrons and reaches 0.92 for electron energy of 5keV. For this energy the detector will be used for the angle- and energy-selective detection of signal electrons in the scanning low energy electron microscope.

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