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The effect of electron bombardment on the electrophysical properties of tellurium thin films
Classified abstracts 1102-1113 23 1102. Automatic system for manufacturing electrical leads. (USSR) An improved automatic system for the manufacture of electrical leads of the type required in vacuum devices is described. The system includes devices for straightening, feeding, and cutting the currentcarrying parts of the leads and is distinguished by the fact that, in order to obtain sections of the lead in specified shapes, it is furnished with a casting device incorporating appropriately-shaped moulds. This arrangement ensures correct mutual positioning of the conductor and insulator and is simple and reliable in operation. M B Starodin, USSR Patent 180,696, Appl 12th Aug 1964, publd 26th March 1966. 23 1103. A sliding joint. (USSR) A modification of an existing sliding joint (of the type used in a mechanotron), consisting of a membrane fastened along a specified contour with a rod of circular cross section passing through the membrane, is described. In the modification proposed, the central rod is made of elliptical cross section so that the coupling as a whole has different rigidities in the mutually-perpendicular directions corresponding to the major and minor axes of the rod. G S Berlin and V A Piskun, USSR Patent 198,842, Appl 6th April 1966, publd 18th Aug 1967.
operating complexities by producing the liquid refrigerant directly from the gaseous state. The simplification is achieved by giving the refrigerating systems a common throttle in order to ensure simultaneous operation with a 180° phase shift, each refrigerating system having an auxiliary regenerator in front of the throttle. A D Suslov et al, USSR Patent 1-90,377, Appl 14th April 1965, pubM 29th Oct 1966. 28. HEATING E Q U I P M E N T AND T H E R M O M E T E R S 28 1109. Germanium resistance thermometry at temperatures below I°K. (USA) The thermometers fabricated for the range of temperatures below 1°K, use compensated germanium with. room temperature resistivity between 0.12 and 0.17 ohm cm. The resistance elements were vacuum encapsulated in black glass. G A Antcliffe et al, Rev Sci Instrum, 39 (2), 1968, 254-255. 28 1110. Method of calibrating thermocouples under vacuum. (USSR) A device is described for calibrating unusual thermocouples, such as titanium alloy-tungsten, under vacuum by means of rf heating at temperatures up to the melting point of the alloy. B Ya Borisov et al, lzmerit Tekh, No 4, 1968, 88-90 (in Russian).
24. VALVES 24 1104. Axially-symmetric electromagnetic high vacuum valve. (USSR) A detailed description is given of an electromagnetic valve with id 70 ram, sealed by an elastomer or by a low-melting point metal gasket. The pressure on the valve seat is 40 kg and its maximum lift is 40 ram. The electromagnet armature, made of steel, is located inside the vacuum space. The coil winding is normally supplied with dc current, but with supply of ac current, the entire valve is baked to 180°C by the effect of eddy currents. B Sh Berenshteyn and V V Kryachko, Pribory Tekh Eksper, 13 (1), Jan-Feb 1968, 161-163 (in Russian). 24 1105. High vacuum metallic valve with elastic loading material. (USSR) A 20 mm id valve is described in which the valve seat is coated with an elastomer and on top of this a 0.5 mm thick copper foil is attached. This metal/metal-and-einstomer sealing provides good thrusting of the seal. After 10,000 operations of the valve, no failure in the tightness was observed. S I Gendel et al, Pribory Tekh Eksper, 13 (2), March-April 1968, 163
(in Russian). 24 1106. A greaseless valve for use in mercury reservoirs. (Great Britain) A greaseless valve suitable for controlling mercury from a reservoir to a high vacuum system is described. The valve has positive absolute shut-off and is capable of fine control. Seals are based on KeI-F, Teflon, Viton and welds. The construction is adaptable for use with manometers, McLeod gauges, Toepler pumps and cut-offs. (USA) T Ishida and J Bigeleisen, J Sci Instrum, Ser 2, 1 (3), 1968, 359-360. 24 1107. Investigation of fast-acting electromagnetic gas-inlet valves.
(USA) For some plasma physics experiments it is necessary to admit a definite quantity of gas into a discharge vessel during a very short time. Valves for such operations were built, and their operation was examined with a photomultiplier and a 4 mm microwave apparatus. By measuring the pressure increase, the total number of particles admitted was determined as a function of the valve parameters. (Germany) H Brinkschulte et al, Rep IPP-I/68; 1PP-3/56, July 1967, 36 pages (Sci Tech Aerospace Reps, 6 (2), 251, N68-11155).
25. BAFFLES, TRAPS AND REFRIGERATION E Q U I P M E N T 25 1108. Apparatus for the liquefaction of gases. (USSR) A modification of a well-known gas-liquefaction system, consisting of a pair of refrigerating systems for preliminary cooling of the gas with subsequent throttling of the latter, is described. The modified version is intended to simplify constructional problems and eliminate
492
III. Vacuum applications 30. EVAPORATION AND SPUTTERING 30:16 The effect of electron bombardment on the electrophysical properties of tellurium thin films, See abstract number 1048. 30 1111. The preparation and properties of CdS films evaporated by electron bombardment. (France) In order to prepare cadmium sulphide films of the highest purity, electron beam evaporation of CdS, both in the form of polycrystals and as a compacted powder, were investigated. In each case the electrical, optical and photoelectric properties were determined. Beth polycrystal and compacted powder sources yielded films with property values identical to the bulk material. The energy levels of electron trapping centres were determined from measurements of thermally stimulated currents, space charge limited currents and decay curves. J P Sorbier et al, Le Vide, 23 (133), Jan-Feb 1968, 32-39 (in French). 30 1112. Sputtering of insulators in an rf discharge. (Great Britain) A technique for the deposition of insulating layers on suitable substrates by sputtering in a r~tdio-frequency excited discharge, is described. The sputtering equipment and vacuum system were designed to provide facilities for the direct comparison of three different methods of sustaining a glow discharge at low pressures: a two-electrode Penning system (diode); a hot cathode discharge (triode); a second rf coil, inductively coupled, directly into the gas (double rf). Deposition rates of a barium aluminosilicate glass, as a function of dc power input, are given for each method, it is shown that high rates of deposition can be obtained using the double rf system, ie rates in the region of 6.6× 10-1°mS -1 (400 •/min) were obtained for a dc power input of approximately 800 watts. Deposition rates were also investigated for a range of argon/oxygen mixtures. A detailed examination of the electrical properties of sputtered barium aluminosilicate glass thin film capacitors was made by sandwiching the dielectric layers between vacuum-deposited aluminium electrodes. Measurements of permittivity (6.15-6.4), tan (0.0017), dielectric strength ( 3 × 1 0 e V cm-t), resistivity about 1015f2cm), and temperature coefficients of capacitance (120 ppm/~'C over the ranges 25-150°C and 100 Hz-100 kHz) were found to compare closely with those of the bulk material. B A Probyn, Vacuum, 18 (5), May 1968, 253-257. 30 1113. Comparison of some physical properties of resistance-heat and electron-gun evaporated SiO films, (Great Britain) A systematic investigation has been conducted to compare the SiO films evaporated by electron-gun and resistance-heat under similar conditions. The physical properties compared are the relative
operating complexities by producing the liquid refrigerant directly from the gaseous state. The simplification is achieved by giving the refrigerating systems a common throttle in order to ensure simultaneous operation with a 180° phase shift, each refrigerating system having an auxiliary regenerator in front of the throttle. A D Suslov et al, USSR Patent 1-90,377, Appl 14th April 1965, pubM 29th Oct 1966. 28. HEATING E Q U I P M E N T AND T H E R M O M E T E R S 28 1109. Germanium resistance thermometry at temperatures below I°K. (USA) The thermometers fabricated for the range of temperatures below 1°K, use compensated germanium with. room temperature resistivity between 0.12 and 0.17 ohm cm. The resistance elements were vacuum encapsulated in black glass. G A Antcliffe et al, Rev Sci Instrum, 39 (2), 1968, 254-255. 28 1110. Method of calibrating thermocouples under vacuum. (USSR) A device is described for calibrating unusual thermocouples, such as titanium alloy-tungsten, under vacuum by means of rf heating at temperatures up to the melting point of the alloy. B Ya Borisov et al, lzmerit Tekh, No 4, 1968, 88-90 (in Russian).
24. VALVES 24 1104. Axially-symmetric electromagnetic high vacuum valve. (USSR) A detailed description is given of an electromagnetic valve with id 70 ram, sealed by an elastomer or by a low-melting point metal gasket. The pressure on the valve seat is 40 kg and its maximum lift is 40 ram. The electromagnet armature, made of steel, is located inside the vacuum space. The coil winding is normally supplied with dc current, but with supply of ac current, the entire valve is baked to 180°C by the effect of eddy currents. B Sh Berenshteyn and V V Kryachko, Pribory Tekh Eksper, 13 (1), Jan-Feb 1968, 161-163 (in Russian). 24 1105. High vacuum metallic valve with elastic loading material. (USSR) A 20 mm id valve is described in which the valve seat is coated with an elastomer and on top of this a 0.5 mm thick copper foil is attached. This metal/metal-and-einstomer sealing provides good thrusting of the seal. After 10,000 operations of the valve, no failure in the tightness was observed. S I Gendel et al, Pribory Tekh Eksper, 13 (2), March-April 1968, 163
(in Russian). 24 1106. A greaseless valve for use in mercury reservoirs. (Great Britain) A greaseless valve suitable for controlling mercury from a reservoir to a high vacuum system is described. The valve has positive absolute shut-off and is capable of fine control. Seals are based on KeI-F, Teflon, Viton and welds. The construction is adaptable for use with manometers, McLeod gauges, Toepler pumps and cut-offs. (USA) T Ishida and J Bigeleisen, J Sci Instrum, Ser 2, 1 (3), 1968, 359-360. 24 1107. Investigation of fast-acting electromagnetic gas-inlet valves.
(USA) For some plasma physics experiments it is necessary to admit a definite quantity of gas into a discharge vessel during a very short time. Valves for such operations were built, and their operation was examined with a photomultiplier and a 4 mm microwave apparatus. By measuring the pressure increase, the total number of particles admitted was determined as a function of the valve parameters. (Germany) H Brinkschulte et al, Rep IPP-I/68; 1PP-3/56, July 1967, 36 pages (Sci Tech Aerospace Reps, 6 (2), 251, N68-11155).
25. BAFFLES, TRAPS AND REFRIGERATION E Q U I P M E N T 25 1108. Apparatus for the liquefaction of gases. (USSR) A modification of a well-known gas-liquefaction system, consisting of a pair of refrigerating systems for preliminary cooling of the gas with subsequent throttling of the latter, is described. The modified version is intended to simplify constructional problems and eliminate
492
III. Vacuum applications 30. EVAPORATION AND SPUTTERING 30:16 The effect of electron bombardment on the electrophysical properties of tellurium thin films, See abstract number 1048. 30 1111. The preparation and properties of CdS films evaporated by electron bombardment. (France) In order to prepare cadmium sulphide films of the highest purity, electron beam evaporation of CdS, both in the form of polycrystals and as a compacted powder, were investigated. In each case the electrical, optical and photoelectric properties were determined. Beth polycrystal and compacted powder sources yielded films with property values identical to the bulk material. The energy levels of electron trapping centres were determined from measurements of thermally stimulated currents, space charge limited currents and decay curves. J P Sorbier et al, Le Vide, 23 (133), Jan-Feb 1968, 32-39 (in French). 30 1112. Sputtering of insulators in an rf discharge. (Great Britain) A technique for the deposition of insulating layers on suitable substrates by sputtering in a r~tdio-frequency excited discharge, is described. The sputtering equipment and vacuum system were designed to provide facilities for the direct comparison of three different methods of sustaining a glow discharge at low pressures: a two-electrode Penning system (diode); a hot cathode discharge (triode); a second rf coil, inductively coupled, directly into the gas (double rf). Deposition rates of a barium aluminosilicate glass, as a function of dc power input, are given for each method, it is shown that high rates of deposition can be obtained using the double rf system, ie rates in the region of 6.6× 10-1°mS -1 (400 •/min) were obtained for a dc power input of approximately 800 watts. Deposition rates were also investigated for a range of argon/oxygen mixtures. A detailed examination of the electrical properties of sputtered barium aluminosilicate glass thin film capacitors was made by sandwiching the dielectric layers between vacuum-deposited aluminium electrodes. Measurements of permittivity (6.15-6.4), tan (0.0017), dielectric strength ( 3 × 1 0 e V cm-t), resistivity about 1015f2cm), and temperature coefficients of capacitance (120 ppm/~'C over the ranges 25-150°C and 100 Hz-100 kHz) were found to compare closely with those of the bulk material. B A Probyn, Vacuum, 18 (5), May 1968, 253-257. 30 1113. Comparison of some physical properties of resistance-heat and electron-gun evaporated SiO films, (Great Britain) A systematic investigation has been conducted to compare the SiO films evaporated by electron-gun and resistance-heat under similar conditions. The physical properties compared are the relative