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2240. Comparison of photoelectron and X-ray spectroscopy studies of GaAs and GaP energy band structure
Classified abstracts 2236-2247
into the N b interior when heated, and no bulk N b - G e compounds were observed. J A Strozier et al, J Appl Phys, 47 (4), 1976, 1611-1615. 36 2236. Formation, structure, and orientation of gold silicide on gold surfaces. (USA) The formation of gold silicide on Au films evaporated onto Si(111) surfaces is studied by Auger electron spectroscopy (AES) and loweaergy electron diffraction (LEED). Surface condition, film thickness, deposition temperature, annealing temperature, and heating rate during annealing are varied. Several oriented crystalline silicide layers are observed. A K Green and E Bauer, J Appl Phys, 47 (4), 1976, 1284-1291. 36 2237. Rotation between SEM micrograph and electron channelling patterns. (GB) Rotation between the normal image seen in the scanning electron microscope (SEM) and electron channelling patterns (ECP) has previously been found for the deflection focus system for generating selected area ECP (SAECP). This note examines the rotation for the after-lens deflection system also used for generating SAECP and characterizes the difference between various modes of SEM use. (USA) D L Davidson, JPhys E: Scient lnstrum, 9 (5), 1976, 371-373. 36 2238. Methods of obtaining in-depth data in surface analysis. (Germany) Determination of the distribution in depth of elements and compounds is closely related with surface analysis. The normal practice is sputtering of surface layers. Recent results, however, have shown that this can seldom be achieved without artifacts. This is why alternative methods, especially non-destructive ones, are of increasing importance. These include above all tilting experiments with ESCA and the energy-dispersive X-ray spectrometer on SEM, information gained from the energy dependence of the escape depth of photo and Auger electrons, the examination of tapered sections by Auger microanalysis and backscattering of high energy ions (RIBS). Although none of these methods allows such a universal application as sputtering by ion bombardment, their possibilities as alternative and control experiments should be exploited to a greater extent. In a number of instances they also offer substantial savings in time. Von R Holm and S Storp, Vakuum-Tech, 25 (3), 1976, 73-78 (in
German). 36 2239. Methods of obtaining in-depth data in surface analysis. (Germany) Determination of the distribution in depth of elements and compounds is closely related with surface analysis. The normal practice is sputtering of surface layers. Recent results, however, have shown that this can seldom be achieved without artifacts. This is why alternative methods, expeciaUy non-destructive ones, are of increasing importance. These include above all tilting experiments with ESCA and the energy-dispersive X-ray spectrometer on SEM, information gained from the energy dependence of the escape depth of photo and Auger electrons, the examination of tapered sections by Auger microanalysis and backscattering of high energy ions (RIBS). Although none of these methods allows such a universal application as sputtering by ion bombardment, their possibilities as alternative and control experiments should be exploited to a greater extent. In a number of instances they also offer substantial savings in time. Von R Holm and S Storp, Vakuum-Tech, 25 (2), 1976, 41-47 (in
German). 36 2240. Comparison of photoelectron and X-ray spectroscopy studies of GaAs and GaP energy band structure. (USSR) Photoelectron spectra of GaAs and G a P are investigated which have been obtained in a vacuum of 10 -9 tort at excitation by ultraviolet light and X-ray radiation of the same surfaces without interruption of vacuum (Germany) G Leonhardt, Fiz Tvercl Tela, 17 (1), 1975, 3-6 (in Russian). 36 2241. Investigation of the oxygen effect on thermal emission of ions of impurity particles from platinum surface. (USSR) Using a mass spectrometer, the emission of ions from platinum surface is investigated at a residual gas pressure of 10-6 torr. Secondary ions were emitted from platinum surface under the bombardment by
2 keV Kr + ions at a current density of 5 × 10-8 A/cm 2. Ionization of neutral particles desorbed from platinum surface was performed by an 300 eV electron beam of 300/~A passing at a distance of 3 m m from platinum surface Particles of impurities of Li, C, Na, Mg, Al, K, Ca, Ti, Cr, Fe, Rb, Sr, Rh and Ba are found on platinum surface. At sufficiently high temperature the particles of impurities are desorbed both in charged and neutral states. The influence of oxygen at a pressure of 1 x 10- s torr on emission of thermal and secondary ions and desorption of neutrals is investigated. The results of experiments performed at elevated temperatures (1573 K) of platinum indicate the influence of oxygen on the diffusion flow of impurity particles from the bulk to the surface through dislocations. L P Rekova et al, Zh Tekh Fiz, 45 (3), 1975, 616-623 (in Russian). 36 2242. Energy spectra of true secondary electrons at barium adsorption on tungsten. (USSR) The influence of the Auger process on energy spectra of true secondary electrons at barium adsorption on tungsten is investigated in a quasispherical capacitor with an antidynatron grid. The Ba deposition and measurements were performed at pressures less than 10 -9 torr. I M Bronshteyn et al, Radiotekh Elektron, 20 (4), 1975, 866-869 (in
Russian). 36 2243. Decoration of mutually completing cleavage surfaces of alkali halide crystals. (USSR) Using electron microscopy observations, decoration of mutually completing surface of NaCI and LiF single crystals, cleaved in flow of gold atoms at a residual pressure of 2 × 10 -6 torr, is investigated. It is found that the mutually completing surfaces of cleavage possess different potential relief. V S Postnlkov et al, Fiz Tverd Tela, 17 (3), 1975, 946-948 (in Russian). 36 2244. Auger spectroscopy of the barium-platinum film system. (USSR) The process of formation of a Ba film on Pt at various temperatures is investigated with the aid of the Auger electron spectroscopy. It is found that at 300 K a continuous Ba film is formed while at 800 to 1000 K an island film results. N M Gnuchev et al, Fiz Tverd Tela, 15 (3), 1975, 937-939 (in Russian). 36 2245. Study of the grain boundary diffusion of iron in tungsten by means of autoradiographic and secondary-ion mass spectrometric methods. (Germany) The aim of the presented work was to determine the grain boundary diffusion coefficients of iron in polycrystalline tungsten in the temperature range 0.3 to 0.6 of the melting point of the host metal. A mathematical model has been developed and microautoradiographic and SIMS methods have been applied in order to measure the diffusion at low relative temperatures. The grain boundary diffusion of iron in polycrystalline tungsten has been determined in the temperature range of 1200 to 2300 K. The SIMS measurements were made by the Cameca IMS 300 type seco~dary ion microscope using 5.5 keV 02 + primary ions. It has been pro r'~.dthat the Arrhenius-type relationship is valid for the whole range vv.th the constant equal to 0.184-0.11 cm -2 s- t and activation energy 7740 =~ 3.70 kcal/g atom. (Hungary) L Kozma et al, Phys Star Sol (a), 26 (2), 1974, 711-720. 36 2246. Preparation of carbon replicas from transmitted GaAs foils for electron microscopical investigations. (Germany) Using an example of thin GaAs foil, the technique of preparation of carbon replica from that portion of the foil, which had been previously observed in a transmission electron microscope and subjected to microscope electron beam bombardment, is described. A Tempel, Krist und Techn, 9 (2), 1974, 137-140. 37. I N O R G A N I C CHEMISTRY, A N A L Y T I C A L CHEMISTRY, DISTILLATION, MISCELLANEOUS C H E M I C A L APPLICATIONS, OIL A N D H Y D R O C A R B O N T E C H N O L O G Y 37 2247. Precise measurement of the thermal expansion of silicon near 40°C. (USA) We report absolute measurements of the thermal-expansion coefficient of single-crystal silicon having a precision of i 0 . 2 % . Five thermal499
into the N b interior when heated, and no bulk N b - G e compounds were observed. J A Strozier et al, J Appl Phys, 47 (4), 1976, 1611-1615. 36 2236. Formation, structure, and orientation of gold silicide on gold surfaces. (USA) The formation of gold silicide on Au films evaporated onto Si(111) surfaces is studied by Auger electron spectroscopy (AES) and loweaergy electron diffraction (LEED). Surface condition, film thickness, deposition temperature, annealing temperature, and heating rate during annealing are varied. Several oriented crystalline silicide layers are observed. A K Green and E Bauer, J Appl Phys, 47 (4), 1976, 1284-1291. 36 2237. Rotation between SEM micrograph and electron channelling patterns. (GB) Rotation between the normal image seen in the scanning electron microscope (SEM) and electron channelling patterns (ECP) has previously been found for the deflection focus system for generating selected area ECP (SAECP). This note examines the rotation for the after-lens deflection system also used for generating SAECP and characterizes the difference between various modes of SEM use. (USA) D L Davidson, JPhys E: Scient lnstrum, 9 (5), 1976, 371-373. 36 2238. Methods of obtaining in-depth data in surface analysis. (Germany) Determination of the distribution in depth of elements and compounds is closely related with surface analysis. The normal practice is sputtering of surface layers. Recent results, however, have shown that this can seldom be achieved without artifacts. This is why alternative methods, especially non-destructive ones, are of increasing importance. These include above all tilting experiments with ESCA and the energy-dispersive X-ray spectrometer on SEM, information gained from the energy dependence of the escape depth of photo and Auger electrons, the examination of tapered sections by Auger microanalysis and backscattering of high energy ions (RIBS). Although none of these methods allows such a universal application as sputtering by ion bombardment, their possibilities as alternative and control experiments should be exploited to a greater extent. In a number of instances they also offer substantial savings in time. Von R Holm and S Storp, Vakuum-Tech, 25 (3), 1976, 73-78 (in
German). 36 2239. Methods of obtaining in-depth data in surface analysis. (Germany) Determination of the distribution in depth of elements and compounds is closely related with surface analysis. The normal practice is sputtering of surface layers. Recent results, however, have shown that this can seldom be achieved without artifacts. This is why alternative methods, expeciaUy non-destructive ones, are of increasing importance. These include above all tilting experiments with ESCA and the energy-dispersive X-ray spectrometer on SEM, information gained from the energy dependence of the escape depth of photo and Auger electrons, the examination of tapered sections by Auger microanalysis and backscattering of high energy ions (RIBS). Although none of these methods allows such a universal application as sputtering by ion bombardment, their possibilities as alternative and control experiments should be exploited to a greater extent. In a number of instances they also offer substantial savings in time. Von R Holm and S Storp, Vakuum-Tech, 25 (2), 1976, 41-47 (in
German). 36 2240. Comparison of photoelectron and X-ray spectroscopy studies of GaAs and GaP energy band structure. (USSR) Photoelectron spectra of GaAs and G a P are investigated which have been obtained in a vacuum of 10 -9 tort at excitation by ultraviolet light and X-ray radiation of the same surfaces without interruption of vacuum (Germany) G Leonhardt, Fiz Tvercl Tela, 17 (1), 1975, 3-6 (in Russian). 36 2241. Investigation of the oxygen effect on thermal emission of ions of impurity particles from platinum surface. (USSR) Using a mass spectrometer, the emission of ions from platinum surface is investigated at a residual gas pressure of 10-6 torr. Secondary ions were emitted from platinum surface under the bombardment by
2 keV Kr + ions at a current density of 5 × 10-8 A/cm 2. Ionization of neutral particles desorbed from platinum surface was performed by an 300 eV electron beam of 300/~A passing at a distance of 3 m m from platinum surface Particles of impurities of Li, C, Na, Mg, Al, K, Ca, Ti, Cr, Fe, Rb, Sr, Rh and Ba are found on platinum surface. At sufficiently high temperature the particles of impurities are desorbed both in charged and neutral states. The influence of oxygen at a pressure of 1 x 10- s torr on emission of thermal and secondary ions and desorption of neutrals is investigated. The results of experiments performed at elevated temperatures (1573 K) of platinum indicate the influence of oxygen on the diffusion flow of impurity particles from the bulk to the surface through dislocations. L P Rekova et al, Zh Tekh Fiz, 45 (3), 1975, 616-623 (in Russian). 36 2242. Energy spectra of true secondary electrons at barium adsorption on tungsten. (USSR) The influence of the Auger process on energy spectra of true secondary electrons at barium adsorption on tungsten is investigated in a quasispherical capacitor with an antidynatron grid. The Ba deposition and measurements were performed at pressures less than 10 -9 torr. I M Bronshteyn et al, Radiotekh Elektron, 20 (4), 1975, 866-869 (in
Russian). 36 2243. Decoration of mutually completing cleavage surfaces of alkali halide crystals. (USSR) Using electron microscopy observations, decoration of mutually completing surface of NaCI and LiF single crystals, cleaved in flow of gold atoms at a residual pressure of 2 × 10 -6 torr, is investigated. It is found that the mutually completing surfaces of cleavage possess different potential relief. V S Postnlkov et al, Fiz Tverd Tela, 17 (3), 1975, 946-948 (in Russian). 36 2244. Auger spectroscopy of the barium-platinum film system. (USSR) The process of formation of a Ba film on Pt at various temperatures is investigated with the aid of the Auger electron spectroscopy. It is found that at 300 K a continuous Ba film is formed while at 800 to 1000 K an island film results. N M Gnuchev et al, Fiz Tverd Tela, 15 (3), 1975, 937-939 (in Russian). 36 2245. Study of the grain boundary diffusion of iron in tungsten by means of autoradiographic and secondary-ion mass spectrometric methods. (Germany) The aim of the presented work was to determine the grain boundary diffusion coefficients of iron in polycrystalline tungsten in the temperature range 0.3 to 0.6 of the melting point of the host metal. A mathematical model has been developed and microautoradiographic and SIMS methods have been applied in order to measure the diffusion at low relative temperatures. The grain boundary diffusion of iron in polycrystalline tungsten has been determined in the temperature range of 1200 to 2300 K. The SIMS measurements were made by the Cameca IMS 300 type seco~dary ion microscope using 5.5 keV 02 + primary ions. It has been pro r'~.dthat the Arrhenius-type relationship is valid for the whole range vv.th the constant equal to 0.184-0.11 cm -2 s- t and activation energy 7740 =~ 3.70 kcal/g atom. (Hungary) L Kozma et al, Phys Star Sol (a), 26 (2), 1974, 711-720. 36 2246. Preparation of carbon replicas from transmitted GaAs foils for electron microscopical investigations. (Germany) Using an example of thin GaAs foil, the technique of preparation of carbon replica from that portion of the foil, which had been previously observed in a transmission electron microscope and subjected to microscope electron beam bombardment, is described. A Tempel, Krist und Techn, 9 (2), 1974, 137-140. 37. I N O R G A N I C CHEMISTRY, A N A L Y T I C A L CHEMISTRY, DISTILLATION, MISCELLANEOUS C H E M I C A L APPLICATIONS, OIL A N D H Y D R O C A R B O N T E C H N O L O G Y 37 2247. Precise measurement of the thermal expansion of silicon near 40°C. (USA) We report absolute measurements of the thermal-expansion coefficient of single-crystal silicon having a precision of i 0 . 2 % . Five thermal499