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1799. Effect of the nature of the evaporation process on heat transfer during evaporation and condensation
Classified abstracts
1793--1805
J Goodman, US Patent 3,239,368 (Cl 117-93.1), 8 Mar 1966, Appl
26 Apr 1962; 5 pages. 3O 1793. Evaporated and recrystallized cadmium sulphide layers. K W Boer et ai, J ApplPhys, 37 (7), 1966, 2664-2678.
(USA)
30 1794. Sputtering yields of several semiconducting compounds under argon ion bombardment. (USA) Sputtering yields of single crystals of SiC, lnSb, GaAs, GaP, CdS, and PbTe under argon ion bombardment have been measured. The energy of the argon ions obtained from a magnetically confined argon arc, ranged from 75 to 600eV. J Comas and C B Cooper, J Appl Phys, 37 (7), 1966, 2820-2822. 30 1795. A LEED study of the epitaxial growth of copper on the (110) surface of tungsten. (USA) Low-energy electron-diffraction (LEED) has been employed in a study of epitaxial deposition of copper on a single crystal (110) face of tungsten under ultrahigh-vacuum conditions. Cobalt was evaporated at I0 " torr from a Knudsen cell placed in the LEED chamber. The flux of copper at the sample could be determined to an accuracy of 4-10 per cent. N J Taylor, Surfitce Science, 4, 1966, 161-194. 30 1796. Coated hot-film probes for measurements in liquids. (USA) Discussion of the problems involved in the application of hot-wire anemometers to turbulence measurements in conducting liquids and a suggested solution which involves the vacuum-deposition of a quartz film I ~ thick on the probe. Anon, DISA Information, Jan 1966, 28. 30 : 56 1797. Thin film thickness measurements during vacuum processing.
31. Evacuation and sealing 31 : 20 : 22 Use of the omegatron for the improvement of the pumping techniques of electron tubes. See abstract number 1675. 31 1801. Initiation of electrical breakdown in vacuum by means of field emission current. (USSR) The parameters causing electric breakdown in vacuum were analyzed theoretically. On the basis of available experimental data, breakdown with flat electrodes was due to the formation of projections on the surface by local melting and evaporation. I N Slivkov, Zh Tekh Fiz, 36 (2), 1966, 34~348 (in Russian). 31:47 1802. Residual gas analysis under operating condition of an electron tube. (German)') A spectrometric method for analysing the evaporation products of an oxide-coated cathode and the chemical composition of the residual gas is described. The photoemission induced within the anodecathode space by electron collision is separated from the red continuum of the cathode by periodic variation of the anode voltage and selective amplification of the varying photoernission recorded by a photomultiplier. By this method, analysis of the evaporation products of the cathode and of the residual gas may be carried out in all tubes in which the anode-cathode space is visible. F Bernhard and H Dusterhort, Vakuum-Technik, 15, Apr 1966, 87-90
(in German). 31 1803. Influence of contaminants on vacuum system performance.
(USA)
(USSR)
Effects of cleanliness of components on vacuum system performance at Atomics International are surveyed. Recommendations for contamination reduction are listed. S Giles, Test Eng and Mgmt, 14, 1965, 2850.
The apparatus measuring the film thickness by means of oscillator resonance frequency is described in detail. (USSR) O M Sorokin and D I Dzhioeva, Pribory Tekh Eksp, 11 (2), Mar-Apr
32. Nucleonics
1966, 18~190 (in Russian). 30 : 37 1798. Method of producing magnetic films for memory devices. (USSR) Methods of preparing magnetic films for memory elements are described. These films are made by vacuum condensation of suitable alloys, with due attention to homogeneity and freedom from adsorbed gases. An appropriate vacuum for this purpose is 5 × 10 -~ torr. The condensation rate must be carefully controlled in order to avoid heating of the film by thermal radiation; the composition must also be regulated so as to minimise magnetostriction effects, and the substrate temperature must be constant so as to avoid thermal strain. The equipment required to satisfy these conditions is described in detail and a method of determining the principal magnetic properties of the resultant films is indicated. G P Zharikov and V V Zorin, Book, "Physical and Technological
Questions of Cybernetics", Kiev, 1966, 73 (in Russian). 30 : 37 1799. Effect of the nature of the evaporation process on heat transfer during evaporation and condensation. (USSR) The effect of the nature of the evaporation process on the rate of evaporation and condensation of sodium and potassium vapours and on the associated heat-transfer coefficients is discussed. Special attention is paid to the diffusion-chemical resistance associated with this process. For pressures close to atmospheric, the heat-transfer coefficient may be very large (250 kW/m ~ deg) even when this resistance is taken into account. Measurements made during the condensation of sodium and potassium vapours show that at low pressures (1-100 torr) diffusion-chemical resistance is absent. This means that, at any rate for low pressures, the condensation coefficient of the diatomic molecules is close to unity. V I Subbotin et al, Teplofiz Vysok Temperatur, 4 (1), 1966, 143-144
(in Russian). 3O 1800. Cathodic sputtering. (Czechoslovakia) A short discussion is given of the known principles of cathodic sputtering, of the fields of application of this method for the preparation of thin films and of its advantages and disadvantages in comparison with the vacuum evaporation method. (Czechoslovakia) J Cervenak, Jemn Mech Opt, 11 (6), June 1966, 164-166 (in
Czech).
32
1804. Methods in the preparation of radioactive materials. (Sweden) Thirteen papers dealing with the preparation of radioactive samples for use in nuclear research are presented. Included are vacuum techniques used in the preparation methods employed. W Parker, Chalmers University of Technology, Gotehorg, Sweden,
Thesis, 1966. 32:18 1805. Study of an induction-type conical plasma source. (USSR) The construction of an induction-type plasma source operating under conditions of considerable pre-ionization is described. The vacuum chamber of the conical electrodeless plasma source is made of molybdenum glass. Measuring probes are led into the chamber via a flange connecting the vacuum chamber to the titanium pumping system, which is backed by a diffusion pump and a liquid-nitrogen trap. The initial vacuum in the system is 10- 6 torr. Results of measurements made with magnetic and double electrostatic probes in the plasma source are presented. I A Kossyi et al, Zhur Tekhn Fiz, 36, (5), 1966, 881 (in Russian).
33. General physics and electronics 33 : 64 : 10 3rd Czechoslovak conference on electronics and vacuum physics. See abstract number 1633. 33:16 High temperature and field treatment of the tungsten tip in a field emission microscope and the adsorption of oxygen and hydrogen. See abstract number 1648. 33 : 18 New finding in the area of the oxide coated cathode emission. See abstract number 1651. 33 : 18 : 16 Caesium adsorption on faces of tungsten single crystals. See abstract number 1655. 33 : 18 Investigation of breakdown traces in systems with an oxide cathode. See abstract number 1657. 33 : 18 Effective extraction of electrons from a modified Penning discharge. See abstract number 1658.
515
1793--1805
J Goodman, US Patent 3,239,368 (Cl 117-93.1), 8 Mar 1966, Appl
26 Apr 1962; 5 pages. 3O 1793. Evaporated and recrystallized cadmium sulphide layers. K W Boer et ai, J ApplPhys, 37 (7), 1966, 2664-2678.
(USA)
30 1794. Sputtering yields of several semiconducting compounds under argon ion bombardment. (USA) Sputtering yields of single crystals of SiC, lnSb, GaAs, GaP, CdS, and PbTe under argon ion bombardment have been measured. The energy of the argon ions obtained from a magnetically confined argon arc, ranged from 75 to 600eV. J Comas and C B Cooper, J Appl Phys, 37 (7), 1966, 2820-2822. 30 1795. A LEED study of the epitaxial growth of copper on the (110) surface of tungsten. (USA) Low-energy electron-diffraction (LEED) has been employed in a study of epitaxial deposition of copper on a single crystal (110) face of tungsten under ultrahigh-vacuum conditions. Cobalt was evaporated at I0 " torr from a Knudsen cell placed in the LEED chamber. The flux of copper at the sample could be determined to an accuracy of 4-10 per cent. N J Taylor, Surfitce Science, 4, 1966, 161-194. 30 1796. Coated hot-film probes for measurements in liquids. (USA) Discussion of the problems involved in the application of hot-wire anemometers to turbulence measurements in conducting liquids and a suggested solution which involves the vacuum-deposition of a quartz film I ~ thick on the probe. Anon, DISA Information, Jan 1966, 28. 30 : 56 1797. Thin film thickness measurements during vacuum processing.
31. Evacuation and sealing 31 : 20 : 22 Use of the omegatron for the improvement of the pumping techniques of electron tubes. See abstract number 1675. 31 1801. Initiation of electrical breakdown in vacuum by means of field emission current. (USSR) The parameters causing electric breakdown in vacuum were analyzed theoretically. On the basis of available experimental data, breakdown with flat electrodes was due to the formation of projections on the surface by local melting and evaporation. I N Slivkov, Zh Tekh Fiz, 36 (2), 1966, 34~348 (in Russian). 31:47 1802. Residual gas analysis under operating condition of an electron tube. (German)') A spectrometric method for analysing the evaporation products of an oxide-coated cathode and the chemical composition of the residual gas is described. The photoemission induced within the anodecathode space by electron collision is separated from the red continuum of the cathode by periodic variation of the anode voltage and selective amplification of the varying photoernission recorded by a photomultiplier. By this method, analysis of the evaporation products of the cathode and of the residual gas may be carried out in all tubes in which the anode-cathode space is visible. F Bernhard and H Dusterhort, Vakuum-Technik, 15, Apr 1966, 87-90
(in German). 31 1803. Influence of contaminants on vacuum system performance.
(USA)
(USSR)
Effects of cleanliness of components on vacuum system performance at Atomics International are surveyed. Recommendations for contamination reduction are listed. S Giles, Test Eng and Mgmt, 14, 1965, 2850.
The apparatus measuring the film thickness by means of oscillator resonance frequency is described in detail. (USSR) O M Sorokin and D I Dzhioeva, Pribory Tekh Eksp, 11 (2), Mar-Apr
32. Nucleonics
1966, 18~190 (in Russian). 30 : 37 1798. Method of producing magnetic films for memory devices. (USSR) Methods of preparing magnetic films for memory elements are described. These films are made by vacuum condensation of suitable alloys, with due attention to homogeneity and freedom from adsorbed gases. An appropriate vacuum for this purpose is 5 × 10 -~ torr. The condensation rate must be carefully controlled in order to avoid heating of the film by thermal radiation; the composition must also be regulated so as to minimise magnetostriction effects, and the substrate temperature must be constant so as to avoid thermal strain. The equipment required to satisfy these conditions is described in detail and a method of determining the principal magnetic properties of the resultant films is indicated. G P Zharikov and V V Zorin, Book, "Physical and Technological
Questions of Cybernetics", Kiev, 1966, 73 (in Russian). 30 : 37 1799. Effect of the nature of the evaporation process on heat transfer during evaporation and condensation. (USSR) The effect of the nature of the evaporation process on the rate of evaporation and condensation of sodium and potassium vapours and on the associated heat-transfer coefficients is discussed. Special attention is paid to the diffusion-chemical resistance associated with this process. For pressures close to atmospheric, the heat-transfer coefficient may be very large (250 kW/m ~ deg) even when this resistance is taken into account. Measurements made during the condensation of sodium and potassium vapours show that at low pressures (1-100 torr) diffusion-chemical resistance is absent. This means that, at any rate for low pressures, the condensation coefficient of the diatomic molecules is close to unity. V I Subbotin et al, Teplofiz Vysok Temperatur, 4 (1), 1966, 143-144
(in Russian). 3O 1800. Cathodic sputtering. (Czechoslovakia) A short discussion is given of the known principles of cathodic sputtering, of the fields of application of this method for the preparation of thin films and of its advantages and disadvantages in comparison with the vacuum evaporation method. (Czechoslovakia) J Cervenak, Jemn Mech Opt, 11 (6), June 1966, 164-166 (in
Czech).
32
1804. Methods in the preparation of radioactive materials. (Sweden) Thirteen papers dealing with the preparation of radioactive samples for use in nuclear research are presented. Included are vacuum techniques used in the preparation methods employed. W Parker, Chalmers University of Technology, Gotehorg, Sweden,
Thesis, 1966. 32:18 1805. Study of an induction-type conical plasma source. (USSR) The construction of an induction-type plasma source operating under conditions of considerable pre-ionization is described. The vacuum chamber of the conical electrodeless plasma source is made of molybdenum glass. Measuring probes are led into the chamber via a flange connecting the vacuum chamber to the titanium pumping system, which is backed by a diffusion pump and a liquid-nitrogen trap. The initial vacuum in the system is 10- 6 torr. Results of measurements made with magnetic and double electrostatic probes in the plasma source are presented. I A Kossyi et al, Zhur Tekhn Fiz, 36, (5), 1966, 881 (in Russian).
33. General physics and electronics 33 : 64 : 10 3rd Czechoslovak conference on electronics and vacuum physics. See abstract number 1633. 33:16 High temperature and field treatment of the tungsten tip in a field emission microscope and the adsorption of oxygen and hydrogen. See abstract number 1648. 33 : 18 New finding in the area of the oxide coated cathode emission. See abstract number 1651. 33 : 18 : 16 Caesium adsorption on faces of tungsten single crystals. See abstract number 1655. 33 : 18 Investigation of breakdown traces in systems with an oxide cathode. See abstract number 1657. 33 : 18 Effective extraction of electrons from a modified Penning discharge. See abstract number 1658.
515