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Si films
Classified
abstracts
575-587
diameter and a heating tungsten foil with thickness of 20 pm is described. A N Kabanov et al, Proc of 9th All-Union Conf on Electron Microsc, Tbilisi 1973, 113 (in Russian). 18:30 575. Thii-lIlrn MIM system as a cold cathode. (USSR)
Thin-film system Al-&N&l is investigated in the mode of injection of hot electrons. The thin fdm Si3N4 has a high electrical strength and the top aluminium electrode with 100 8, thickness is semitransparent. The basic processes at operation of the thin-am cold cathode are formed by tunnel emission of electrons from the lower electrode in the conduction band of dielectric and by heating of electron gas by electric field. Thin-&n cold cathodes for vacuum integrated circuits and cathode ray tubes were developed and examined. G A Vorobev et al, Proc of All-Union Conf on Dielectric Electronics, FAN Tashkent 1973, 40 (in Russian). 576. Photogeneration of carriers and emission MIS structures. (USSR)
18 of hot electrons from
Operation of a thin-film system metal-insulator-semiconductor as a converter of optical signal (image) into emission of electrons into vacuum is considered. Elementary processes as photogeneration of carriers in semiconductor, their injection into dielectric, acceleration in dielectric and emission into vacuum through an ultrathin metallic electrode are discussed. F M Benson and Yu B Yankevich, Proc of AlI- Union conf on Dielectric Electronics, FAN Tashkent 1973; 29-30-(in Russian). 18 577. Destruction
of crystalline emitters by electrons. (USSR)
The results of investigation of variations in the coefficients of secondary electron emission and quantum yields of alkaline earth metal oxides at their irradiation with electrons are presented. It is found that the variations in the coefficient of secondary electron emission at room temperature are due to generation of colour centres and at elevated temneratures due to thinning of emitting oxide layer. Ways for increasing current stability of secondary emitters are proposed. A M Tyatikov, Co11of Works Dedic to 80 Annivers of Birth of Acad A A Lebedev, Mashinostroenie Leningrad 1973, 162-174 (in Russian).
II. Vacuum 25. BAFFLES
apparatus
and auxiliaries
TRAPS AND REFRIGERATION
EQUIPMENT 25
578. Cooled sorption trap. (USSR) Construction of a sorption trap with conductivity of 100 l/set and cooled with liquid nitrogen is described. Titanium plates with oxidized surface are used as sorbent. For degassing walls and for regeneration of the sorbent the trap is heated to 400°C. The trap is intended for protection of evacuated volume against vapours and cracking products of diffusion pump oils. The trap enables one to maintain pressure of less than 2 x 10T9 torr without presence of hydrocarbons. S F Grishin et al, Probl of Atomic Science and Technol, No 1, Co& Kharkov 1973, 51-54 (in Russian).
28 580. Temperature determination of thin sapphire substrates. (USA) A technique is presented which allows for a noncontact temperature
determination of thin sapphire substrates with ordinary laboratory instrumentation. The technique utilizes the property of expansion with temperature. A calibration curve of sapphire substrate temperature vs heater temperature is deduced. This calibration scheme can be used for other substrate materials which are transparent in the visible region such as fused silica, glass, and many crystals for which thermal expansion data are known. EL Paradis and A J Shuskus, J Vat Sci TechnoI, 11(4), 1974,824-825. 581. Measurement of temperature bead thermocouple. (USSR)
28 of a flow of rarefied gas by multi-
Physical bases of utilization of a multi-bead thermocouple for investigation of nonisothermal flows of rarefied gases are given. D P Lebedev and E F Andreev, Zzv VU2 Priborostr, 16 (ll), 1973, 119-l 23 (in Russian). 28 582. A vacuum furnace for growth of single crystals of alloys by the Bridgman method. (USSR)
A vacuum furnace for growth of single crystals of alloys by the Bridgman method at temperatures upto ISbOY and a vacuim of 10d3 torr is described. The oossibilitv of utilization of black bodv as an absorber of heat energy-for producing a high axial tempera&e gradient is shown. Single crystals of iron-nickel alloys with high uniformity of orientation along the whole length have been grown in the furnace. V I Karmanchuk, Rep of Kirgiz Univers Phys Sciences, No 2, 1973, 52-57 (in Russian).
Ill.
Vacuum
applications
30. EVAPORATION
AND SPUTTERING
30 583. Local heteroepitaxial films prepared by electron-beam technology. (USSR) Local heteroepitaxial Ge films on Si have been prepared by means of electron-beam technology. The dependence of quality of prepared films on technological conditions during deposition is shown. The results of investigation of structure, surface morphology and electrophysical properties of the prepared films are presented. A P Dostanko et al, Electron Obrab Mater, No 6, 1973, 61-63 (in Russian). 30 584. Formation
of phases in Ni/Si lilms. (Germany)
Formation of phases in thin Ni/Si films during annealing is investigated in an electron microscope. Subsequent electron-beam evaporation of Si and Ni was carried out in a vacuum of 10e5 torr on glass substrates with previously deposited SiOZ layer. It is found that phase transformations in the studied films are determined by kinetics of transformations and not by thermodynamic stability. U Beck et al, Krist und Techn, 8 (lo), 1973, 1125-1129 (in German). 30 585. On structure of PbTe thin 6bns. (USSR)
28. HEATING
EQUIPMENT
AND THERMOMETERS 28 intermetallic evaporation
579. Power requirements of resistance-heated sources. (USA) There is a need in the metallizing industry for a rapid method, based on sound theory, for determining the voltage and current requirements for the operation of resistance-heated intermetallic aluminium evaporation boats. This paper shows how these power requirements can be adequately predicted in terms of operating temperature, two partially reduced dimensional parameters and the resistivity of the composite material. A solution of the total heat-flow equation for a model situation with appropriate simplifications and assumptions is presented. Experimental data are fitted to this simplified equation and the resultant calculated data are presented in graphical form suitable for generating computer tabulated data for all possible boat geometries and resistivities of Sylvania Intermetallic Composites No 17 or No 18. E D Parent, J V&u Sci Technol, 11 (4), 1974, 820-823. 180
Using the method of electron diffraction, structure of thin (lOO600 A) PbTe thin films, prepared by vacuum condensation on NaCl substrates covered with carbon layers, is investigated. The deposition temperature of PbTe films was varied in the range of 300 to 570°K. E V Rakova and S A Semiletov, Kristalograf, 18 (6), 1973, 1272-1274 (in Russian). 30 586. Nucleation of defects at gallium arsenide epitaxy. (USSR)
Using the methods of replica electron microscopy, the process of nucleation of defects at early stages of GaAs thin film epitaxial growth in the svstem Ga-AsCl,-HZ is investigated in dependence on the treatment of substrate. L G Lavrenteva et al, Struct Defects in Semicon, Coil, Novosibirsk 1973, 50-53 (in Russ&). 30 587. Field effect in indium nitride. (USSR)
The field effect is investigated in indium nitride films evaporated on surface of ferroelectric ceramics of lead titanate-zirconate or barium
abstracts
575-587
diameter and a heating tungsten foil with thickness of 20 pm is described. A N Kabanov et al, Proc of 9th All-Union Conf on Electron Microsc, Tbilisi 1973, 113 (in Russian). 18:30 575. Thii-lIlrn MIM system as a cold cathode. (USSR)
Thin-film system Al-&N&l is investigated in the mode of injection of hot electrons. The thin fdm Si3N4 has a high electrical strength and the top aluminium electrode with 100 8, thickness is semitransparent. The basic processes at operation of the thin-am cold cathode are formed by tunnel emission of electrons from the lower electrode in the conduction band of dielectric and by heating of electron gas by electric field. Thin-&n cold cathodes for vacuum integrated circuits and cathode ray tubes were developed and examined. G A Vorobev et al, Proc of All-Union Conf on Dielectric Electronics, FAN Tashkent 1973, 40 (in Russian). 576. Photogeneration of carriers and emission MIS structures. (USSR)
18 of hot electrons from
Operation of a thin-film system metal-insulator-semiconductor as a converter of optical signal (image) into emission of electrons into vacuum is considered. Elementary processes as photogeneration of carriers in semiconductor, their injection into dielectric, acceleration in dielectric and emission into vacuum through an ultrathin metallic electrode are discussed. F M Benson and Yu B Yankevich, Proc of AlI- Union conf on Dielectric Electronics, FAN Tashkent 1973; 29-30-(in Russian). 18 577. Destruction
of crystalline emitters by electrons. (USSR)
The results of investigation of variations in the coefficients of secondary electron emission and quantum yields of alkaline earth metal oxides at their irradiation with electrons are presented. It is found that the variations in the coefficient of secondary electron emission at room temperature are due to generation of colour centres and at elevated temneratures due to thinning of emitting oxide layer. Ways for increasing current stability of secondary emitters are proposed. A M Tyatikov, Co11of Works Dedic to 80 Annivers of Birth of Acad A A Lebedev, Mashinostroenie Leningrad 1973, 162-174 (in Russian).
II. Vacuum 25. BAFFLES
apparatus
and auxiliaries
TRAPS AND REFRIGERATION
EQUIPMENT 25
578. Cooled sorption trap. (USSR) Construction of a sorption trap with conductivity of 100 l/set and cooled with liquid nitrogen is described. Titanium plates with oxidized surface are used as sorbent. For degassing walls and for regeneration of the sorbent the trap is heated to 400°C. The trap is intended for protection of evacuated volume against vapours and cracking products of diffusion pump oils. The trap enables one to maintain pressure of less than 2 x 10T9 torr without presence of hydrocarbons. S F Grishin et al, Probl of Atomic Science and Technol, No 1, Co& Kharkov 1973, 51-54 (in Russian).
28 580. Temperature determination of thin sapphire substrates. (USA) A technique is presented which allows for a noncontact temperature
determination of thin sapphire substrates with ordinary laboratory instrumentation. The technique utilizes the property of expansion with temperature. A calibration curve of sapphire substrate temperature vs heater temperature is deduced. This calibration scheme can be used for other substrate materials which are transparent in the visible region such as fused silica, glass, and many crystals for which thermal expansion data are known. EL Paradis and A J Shuskus, J Vat Sci TechnoI, 11(4), 1974,824-825. 581. Measurement of temperature bead thermocouple. (USSR)
28 of a flow of rarefied gas by multi-
Physical bases of utilization of a multi-bead thermocouple for investigation of nonisothermal flows of rarefied gases are given. D P Lebedev and E F Andreev, Zzv VU2 Priborostr, 16 (ll), 1973, 119-l 23 (in Russian). 28 582. A vacuum furnace for growth of single crystals of alloys by the Bridgman method. (USSR)
A vacuum furnace for growth of single crystals of alloys by the Bridgman method at temperatures upto ISbOY and a vacuim of 10d3 torr is described. The oossibilitv of utilization of black bodv as an absorber of heat energy-for producing a high axial tempera&e gradient is shown. Single crystals of iron-nickel alloys with high uniformity of orientation along the whole length have been grown in the furnace. V I Karmanchuk, Rep of Kirgiz Univers Phys Sciences, No 2, 1973, 52-57 (in Russian).
Ill.
Vacuum
applications
30. EVAPORATION
AND SPUTTERING
30 583. Local heteroepitaxial films prepared by electron-beam technology. (USSR) Local heteroepitaxial Ge films on Si have been prepared by means of electron-beam technology. The dependence of quality of prepared films on technological conditions during deposition is shown. The results of investigation of structure, surface morphology and electrophysical properties of the prepared films are presented. A P Dostanko et al, Electron Obrab Mater, No 6, 1973, 61-63 (in Russian). 30 584. Formation
of phases in Ni/Si lilms. (Germany)
Formation of phases in thin Ni/Si films during annealing is investigated in an electron microscope. Subsequent electron-beam evaporation of Si and Ni was carried out in a vacuum of 10e5 torr on glass substrates with previously deposited SiOZ layer. It is found that phase transformations in the studied films are determined by kinetics of transformations and not by thermodynamic stability. U Beck et al, Krist und Techn, 8 (lo), 1973, 1125-1129 (in German). 30 585. On structure of PbTe thin 6bns. (USSR)
28. HEATING
EQUIPMENT
AND THERMOMETERS 28 intermetallic evaporation
579. Power requirements of resistance-heated sources. (USA) There is a need in the metallizing industry for a rapid method, based on sound theory, for determining the voltage and current requirements for the operation of resistance-heated intermetallic aluminium evaporation boats. This paper shows how these power requirements can be adequately predicted in terms of operating temperature, two partially reduced dimensional parameters and the resistivity of the composite material. A solution of the total heat-flow equation for a model situation with appropriate simplifications and assumptions is presented. Experimental data are fitted to this simplified equation and the resultant calculated data are presented in graphical form suitable for generating computer tabulated data for all possible boat geometries and resistivities of Sylvania Intermetallic Composites No 17 or No 18. E D Parent, J V&u Sci Technol, 11 (4), 1974, 820-823. 180
Using the method of electron diffraction, structure of thin (lOO600 A) PbTe thin films, prepared by vacuum condensation on NaCl substrates covered with carbon layers, is investigated. The deposition temperature of PbTe films was varied in the range of 300 to 570°K. E V Rakova and S A Semiletov, Kristalograf, 18 (6), 1973, 1272-1274 (in Russian). 30 586. Nucleation of defects at gallium arsenide epitaxy. (USSR)
Using the methods of replica electron microscopy, the process of nucleation of defects at early stages of GaAs thin film epitaxial growth in the svstem Ga-AsCl,-HZ is investigated in dependence on the treatment of substrate. L G Lavrenteva et al, Struct Defects in Semicon, Coil, Novosibirsk 1973, 50-53 (in Russ&). 30 587. Field effect in indium nitride. (USSR)
The field effect is investigated in indium nitride films evaporated on surface of ferroelectric ceramics of lead titanate-zirconate or barium