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The edge effect, which manifests itself especially in an edge over-brightening in images formed by shallow escape depth signals, is addressed. Attempts had been made to utilize the ratio technique which was developed for suppression of other spurious contrasts in Auger micrographs; it consists in relating the Auger signal to a suitable energy filtered background signal. A systematic comparison of a quantified edge effect in both the Auger images and the energy selected background images is reported here. Surface steps on Si and W surfaces and a W terrace edge on a Si substrate were used at 3 to 20keV primary electron energy, both low and high energy Auger electrons of Si and W were registered together with a background of up to 3 keV. Results have shown that the edge effect is less pronounced with the background so that any ratioing leads to an undercorrection. The best suppression (nearly acceptable for low energies, both primary and Auger ones) is obtained when using the background between 50 and 200 eV as the reference signal.

If any not absolutely smooth and homogeneous nonconductive surface is observed in SEM, a locally variable charging appears which produces local electrical fields that destroy the image. The surface charge depends on the total electron yield σ, i.e. the number of outgoing electrons divided by the number of the incoming ones, on the primary current, resistance between the field of view and the earth, surrounding gas pressure and time. A charge balance is established between primary and emitted electron currents, the specimen current taking charges off the surface, and the charged particle bombardment from the atmosphere, which can be neglected in high vacuum, σ changes with the landing energy of primary electrons: near to zero energy, σ < 1, and the surfaces charge negatively. For nearly all materials, between two characteristic energy values E I and E II , σ exceeds unity and the charge is positive, while above E II , σ < 1 again and a negative charge appears. E I can be found usually between 80 and 300 eV and E II amounts to one or a few keV and depends on the electron impact angle. A novel method is proposed consisting in approaching one of the critical landing energies E I or E II where σ → 1 and the surface charge formation is suppressed to a level corresponding to the intensity of spontaneous discharging. The retarding field principle of low energy SEM realization, which minimizes the point resolution changes with the landing energy, makes both E I and E II equally well accessible. In order to find the critical energy without getting the specimen intensively charged, we recommend to measure, quickly enough from the point of view of the charging process duration, the time dependence of the signal in a single pixel by stepwise approaching the landing energy of the slowest change, i.e. the acceptably approximated critical energy. A model of the image signal vs. time development is presented, together with a description of algorithms and software for the critical energy measurement. The preliminary results presented confirm our basic ideas regarding the method.

The reflectance of very slow electrons from solids and its electron energy dependence are shown as characteristic for the crystal system and its spatial orientation so they can serve, e.g., to fingerprinting the orientation of grains in polycrystals. Measurements on single crystals and polycrystals are validated via electron backscatter diffraction analyses. Sensitivity of the method to fine details of crystallinity is demonstrated.

We discuss an extension to the transmission mode of the cathode-lens-equipped scanning electron microscope, enabling operation down to the lowest energies of electrons. Penetration of electrons through free-standing ultrathin films is examined along the full energy scale, and the contribution of the secondary electrons (SEs), released near the bottom surface of the sample, is shown, enhancing the apparent transmissivity of the sample to more than 100%. Provisional filtering off of the SEs, providing the dark-field signal of forward-scattered electrons, was made using an annular 3-D adjustable detector inserted below the sample. Demonstration experiments were performed on the graphene flakes and on a 3-nm-thick carbon film. Electron penetrability at the lowest energies was measured on the graphene sample.

The backscattering contrast was studied using silicon-metal-film sandwiches in which the incomplete metal layer consists of a regular array of strips. For various combinations of metals and thin film materials, data concerning contrasts of the strips in Auger emission are presented. For different configurations the Auger image contrast varies in the magnitude and even contrast reversal is observed in the dependence on the primary energy. It even varies for the different constituents of the surface films.

The importance of high resolution imaging of dopant contrast in semiconductor structures parallels the continuous increase in the degree of their integration and complexity and in the size of substrates. Some scanning electron microscopy modes show moderate contrast between differently doped areas, but its detailed interpretation remains questionable, in particular, as regards the measurement of the dopant concentration. Photoemission spectromicroscopy on silicon substrates with patterns of opposite-type dopants suggests that the p∕n contrast is primarily related to local differences in the absorption of hot electrons along their trajectory toward the surface. This explanation is also expected to be valid in the interpretation of image contrasts formed by secondary electrons or very slow backscattered electrons. Wide-field photoemission electron microscopy has proven itself a fast imaging method providing large p-n contrast and the prospect of high-level resolution.

The paper describes the physical basis and the structure of the algorithms included in the software package for automatic spectrum processing developed recently as an option to the Tesla BP 350.1 Automatic Auger electron spectrometer.

This paper describes the principles of the method of electron spectra collection based on the spectrum statistics, and its realization by a microcomputer system developed for electron spectrometer control and for data processing. Electrons passing through the bandpass energy filter are detected as pulses and counted by a 24-bit counter. Another counter collects the pulses of a reference signal; for fixed timing, the reference counter is clocked with an oscillator. Using the total secondary emission current as the reference signal, the emission fluctuations are eliminated and, finally, the signal from a second broader concentric window allows us even to eliminate the background. The measurement of the single spectrum run in any energy interval is governed by the ratio of signal to statistical noise. This value defines the binary order of the reference counter carry signal that stops the signal sample collection. In this way a constant value of signal-to-noise ratio is kept throughout the whole spectrum. The 24-bit sample is then fitted to a 16-bit window according to a preselected value of “sensitivity”. The 16-bit result is stored or accumulated in the “immediate” memory. A reduced 8-bit sample is stored and possibly displayed on a screen. To improve the signal-to-noise ratio, easily-observable fast spectrum runs are accumulated. In this case the microcomputer calculates the new measurement timing so that after the accumulation of 256 runs all bits in the selected dynamical range of measurement are statistically valid. Some results are presented to illustrate the advantages of the microcomputer controlled spectrum accumulation method with measurement time correction. They are compared with single sweep measurements obtainable with classical instruments.

This paper concerns the problem of testing the image resolution in scanned electron micrographs, namely from the point of view of the image contrast for the standard gold/carbon test specimen within the full energy scale, down to eV units. Microscopes equipped with a cathode lens are considered and experimental results are presented for three devices differing in vacuum conditions and fields surrounding the specimen. At very low energies, the contrast is shown to either invert or disappear and this ambiguity is discussed and confronted with data simulated on the basis of measured electron yields from gold and carbon. It is concluded that the observations can be explained in terms of the surface cleanliness and strength of the surrounding fields.

The 100Cr6 steel represents the traditional bearing material. the conventional full annealing process used for this ball-bearing steel took considerably longer owing to more time-consuming operations. Conventional treatment of steels includes austenitizing treatment at 780°C for 4 hours, cooling to 720°C for 8 hours, holding at 720°C for 4 hours, furnace cooling to 580°C and free cooling to room temperature. The aim of work performed is to obtain full-annnealing of 100Cr6 steel for shorter time. The procedure proposed can be considered as one possible principles of a simplified bearing parts production technology. By annealing of pipes at 700°C in the protective atmosphere the complete spheroidization of carbides occurred. It is confirmed by SEM analysis. Mechanical properties obtained are in accordance to the requirements. Results obtained in this work suggest thet the production of pipes with this procedure, including SEM analysis, will be successfully.