The time-dependent charging process of an insulating specimen under electron beam irradiation is calculated by taking into account the charge continuity equation, the Poisson equation, Ohm's law and the electron-beam-induced conductivity. The energy and the charge deposition distributions are calculated by the Monte Carlo simulation of electron trajectories taking into account the electric field distribution in the specimen. The time-dependent charge and potential distributions are obtained in the present calculation. As the electron beam energy is 10 keV and the specimen is a 1-mm-thick poly-methyl-methacrylate (PMMA) wafer, the surface potential increases to a positive value at first, and then becomes a negative one. This charging process agrees with experimental findings.

A new Monte Carlo calculation model is presented to simulate not only the primary electron behavior but also the secondary electron cascade in a specimen bombarded with an electron beam. Electrons having energy greater than 0.1 keV are treated as ‘‘fast electrons’’ and the previous single scattering Monte Carlo model is adopted. Electrons having energy smaller than 0.1 keV are treated as ‘‘slow electrons’’ and the electron cascade Monte Carlo model is used. The calculated results for the energy distribution of secondary electrons, and primary electron energy dependence of the total secondary yield and the backscattering yield are in good agreement with experimental results.

Supposing that an insulator is charged-up negatively by an accumulation of incident primary electrons, we study how much the subsequent incident electron is influenced by the charge in the specimen. We introduce a new Monte Carlo simulation model of electron scattering in a solid taking into account an electric field around the simulated electron. In a present study the incident electron energy is 20 keV, and the insulator is a poly-methyl-methacrylate wafer of 1 mm in thickness. This paper clarifies the changes in some physical quantities, e.g., the backscattering coefficient, energy deposition, etc. due to the specimen charging during an electron beam irradiation.

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A Monte Carlo calculation model is developed to simulate trajectories of primary and ionized electrons in metals. It is constructed especially for a quantitative analysis of images in the scanning electron microscope. We perform a direct simulation considering each differential scattering cross section for elastic scattering, inner-shell electron ionization, conduction band electron ionization and bulk plasmon excitation. The spatial distribution of secondary electron emission calculated is narrower than that of backscattered electron emission at the Al surface for 1 keV primary electrons, but depending on the condition, this tendency may not always be found. The spatial distributions of both secondary and backscattered electrons show the size effect, and if the specimen to be observed is smaller, the practical resolution will be better in the scanning electron microscope.

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A new Monte Carlo simulation of electron scattering has been achieved for extension to the low-energy region and to heavy elements such as Au. The Kanaya-Okayama equation, which includes adjustable parameters, is used for the calculation of energy loss instead of the Bethe equation. Further, the Mott equation, which is obtained from a more exact treatment for elastic scattering, is used instead of the screened Rutherford equation for angular scattering. The calculated results are compared with various kinds of experimental results such as the electron range, the backscattering coefficient, and the depth distribution of energy dissipation. The theoretical results are found to be in satisfactory agreement with the experimental results.

The effects of electron-elecbon interactions on the magnetic properties of alkali metals are reviewed. At the densities of the solid or liquid near the melting point, magnetic properties are well described by a genedimtion of the Stoner model. This approach &%aunts for enhancement ofthe magnetic susceptibility and deviations from the Koninga relation between the NMR Knight shift and the corresponding wnuibution to nuclear spin-lattice relaxation. When expanded by heating the liquid toward the liquid-gas critical point, the magnetic properties and optical reflectivity of caesium develop new characteristics best described by correlation enhancement of the effective mass. Behaviour of the Koninga relation deviation implies a change in the spin wrrelations from essentially ferromagnetic in the dense liquid to antiferromagnetic in the dilute mehl. The shilarity of thme effens to those observed in the high Tc supemndndng cupntes is discussed.