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The purpose of this paper is to characterize interface states in Au/InSb/InP(1 0 0) Schottky-type diodes and determine the effect of InSb surface preparation on the energy density distribution and relaxation time of the interface state. In the latter diode, InSb forms a fine restructuration layer allowing to block In atoms migration to surface. We have proceeded as follows: first, a great amount of antimony has been evaporated and, as a second step, the excess antimony is removed by heating the substrate at 300°C. The characteristic parameters of the interface states are derived from the capacitance-voltage C ( V G ), conductance–voltage G ( V G ) measured as a function of frequency and current–voltage I ( V G ) under forward biases. The mean density of interface states N ss estimated was 3.05×10 12 eV −1 cm −2 , the interface states were responsible for the non-ideal behavior of the I ( V G ) characteristics of the diodes. The relaxation times are independent of the bias and varies with N ss in the range 7.1×10 −4 s and 3.7×10 −3 s.

The percentage, η e ′ of electrons elastically reflected by a substrate is a fundamental parameter for elastic peak electron spectroscopy (EPES). A Retarding Field Analyser with its large acceptance angle can be used for this spectroscopy. However, distortion is observed in the low energy side of the recorded elastic peak, increasing with the energy of the impinging electrons, which introduces difficulty for η e measurement. To eliminate this difficulty, we propose in this paper a method to obtain η e using a reference curve. The process is applied to the study of the Ag Mo system, as well as experimental determination of the mean free path of electrons in indium samples.

The paper deals with porous Si (PSi) samples, prepared with different parameters (substrate, current density, solution, etc.) of anodization and anodic oxidation. The porosity of samples varied between 36 and 78%, their thickness was 1–5 p.m. The samples were studied in six laboratories using complementary methods. The spectra of elastic reflection coefficients r e (E p ) are characteristic of the composition and they are affected by the structure of the surface layer. They were measured with a retarding field analyser using spectrometer correction and deduced from the elastic peak versus E p primary energy. The r e (E p ) showed a dramatic decrease in the 50–100 eV range with H adatoms on the surface, produced by HF treatment. It is caused by attenuation and multiple elastic reflections of electrons on the porous surface with H adatoms. An oxidized sample showed a contrary effect, which can be explained by the elastic reflection cross-sections of Si and O in this low energy range. Valence band XPS spectra were measured with a KRATOS XSAM 800 analyser. They showed changes with HF treatment and porous structure. To avoid difficulties with STM due to the oxide, the surface topography was mapped by atomic force microscopy, resulting in 0.3–0.9 nm roughness on samples of 36% porosity.

The retarding field analyser (RFA) proved to be advantageous in electron spectroscopy due to its high luminosity and by providing LEED simultaneously with AES and EPES. RFA is very efficient for determining the inelastic mean free path of electrons by EPES. Dolinski et al measured the elastic peak by repelling the electron beam using a bias potential on the sample. In this paper a further development of this procedure is described supplying the true percentage of elastically scattered electrons collected by RFA. The percentage has been determined by our RFA with optimized bias potential of the sample for primary energies between 100 and 2000 eV. It was deduced from the high energy side of the elastic peak because the background affects the detected signal on the low energy side. The experimental curve of elastic reflection coefficient is presented for indium. The measured elastic peak is distorted by the analyser. The spectrometer response of an RFA was determined by analysing the peak shape of deflected electrons after optimization of the bias voltage of the sample. The peak shape shows asymmetry since the low energy side differs from the Gaussian like high energy side. The distortion produced by RFA is similar to that observed by Taylor. It is enhanced by the background adjacent to the elastic peak. A computer algorithm was elaborated for reconstruction of the elastic and Auger peaks. Corrected curve is presented for indium Auger peak.

Our Monte Carlo simulation for electron trajectories in the crystal used for EPES has been improved for all angular studies. The percentage of reflected electrons can be obtained for different directions of the primary beam and also for different backscattering angles. The simulation is compared with experimental results performed on a pure copper sample.