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727. Reactive evaporation in ionized gases
Classified
abstracts
723-734
couple type TVB manufactured for measurement of high-frequency currents can be used for measurement of absolute pressures in the range of 1.33to 1330 Pa with a relative average square error of 5 per cent. An apparatus with McLeod gauge for calibration of the thermocouple gauge is described. E G Baldin et al, Izmerit Tekh, No 12, 197 I, 42-43 (in Russian). 22 723. Calibration of thermal-conductivity vacuum gauges for different gases. (USSR) A formula is derived, which describes the calibration curves for different gases and their mixtures, for a thermocouple vacuum gauge type VSB-1 operated in the regime of constant temperature. A A Birsbert, Izmerit Tel&, No 7, 197 1, 75 (in Russian). 28. HEATING
EQUIPMENT
AND THERMOMETERS
28 724. Tungsten-rhenium thermocouple for oxidation ambients. (USSR) It is shown that thermocouples of tungsten-rhenium alloys with protective coating of vacuum deposited iridium film and alundum layer can be used for measurement of temperature up to 2400°C in oxidation ambients. I N Akimovich et al, lzmerit Tekh, No 7, 197 I, 76 (in Russian). 28 725. Device for sample heating in a vacumn system. (USSR) A quartz glass device in a vacuum system for heating small samples of materials in vacuum by an external furnace or by induction heating up to I lOO”C, is described. G A Mochalov, Zavodsk Lab, 37 (8), 1971, 995-996 (in Russian).
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
30 726. A triode-rf-sputtering system for film deposition in the lo-” torr range. (Germany) Sputtering modules with low-voltage arcs allow high-rate sputtering of metals, even at pressures below one micron. In the system described, the sputtering chamber has the same potential as the anode and the plasma arc is conducted to the target by a static magnetic field. With an rf-induced negative target voltage dielectric films may be produced since total coverage of the anode with the sputtering material is impossible. Also interference between the rf- and arccurrents are presented. With the same system, reactively sputtered dielectric films such as SiOz, Al,O,may be produced. 0 Sagev, Vakuum-Technik, 20 (8), Dee 1971, 225-23 1 (in German). 30 727. Reactive evaporation in ionized gases. (Germany) Evaporation techniques are reviewed and some problems considered. A new method is described in which reactive evaporation is carried out in ionized gases, the reaction gas being ionized in a discharge tube with high current density and emerging through a nozzle in the wall of the tube directly into the high vacuum region. Parameters for the production of SiO,, SiO,N, and TiOz films are presented as well as their optical properties, stability, structure, and internal stress. All films proved to be very stable, showed smooth surfaces and an x-ray amorphous structure. The SiO, films were free of absorptance within the accuracy of measurement at least down to 190 nm and had the same refractive index as bulk quartz glass. On unheated substrates, practically non-absorbing TiO, films were obtained with refractive indices up to 2.3. W Heitmann, Vakuum-Technik, 21 (I), Feb 1972, 1-11 (in German). 30 728. Energy spectra of the products of cathodic sputtering in the bombardment of metals by light ions. (USSR) Energy spectra are calculated taking account of the successive collisions of a primary ion with atoms of crystal lattice. Good agreement with experimental data is obtained. V I Veksler, Izv AN SSSR Ser Fiz, 3.5 (2), 1971, 379-383 (in Russian). 30 729. Interdiffusion and compound formation in thin films of Pd or Pt on Si single crystals. (Germany) Transmission electron microscopy techniques were used to observe compound formation during diffusion in couples composed of thin films of Pd or Pt on Si single crystal wafers. Platinum films were deposited by vacuum evaporation using an electron gun, palladium
films were evaporated from a tungsten filament. In Pt-Si diffusion couples three compounds Pt,Si, Pt$i and PtSi were found. For Pd-Si diffusion couples the major phase was Pd,Si with only small amounts of PdSi formed after vacuum annealing. (USA) J Drobek et al, Whys Stat Sal (a), 8 (I), Nov 1971,243-248. 30 730. Synthesis of highly oriented cadmium and zinc chalcogenide films of definite structure. (Hungary) The effects of the degree of deviation from thermodynamic cquilibrium, evaporator construction, and nature of the orienting substrate, on the growth of monocrystalline cadmium and zinc chalcogenide films are investigated during condensation in a vacuum of lop4 to 10e5 torr. Quartz ampoules of the Knudsen cell type with one effusive aperture (1-2 mm) or 100 apertures (0.2 mm) were used as evaporators. (USSR) I P Kalinkin et al, Proc Inter Canf’Ph~s Chem Semicon Heterojunc Layer Strut, 3, Akademiai Kiada Budapest 1971, 153- 162. 30 731. Some properties of vacuum evaporated films of aluminium, nickel, cobalt, copper and Cu-Cr-Al alloy. (USSR) Electrical properties, adhesion, thermal stability, weldability and structure of vacuum evaporated films of Al, Ni, Co, Cu and Cu-Cr-Al alloy are investigated. The films were evaporated from a resistance heated tungsten evaporator in vacuum at 5 x IO-” to 1 :’ 10e5 torr in a system with efficient liquid nitrogen traps. The average condensation rate was 5 to 10 &sec. Structure of the fihns was investigated in an electron microscope. It is shown that electrical resistivity of the pure metal films is higher than that of the original bulk materials while the resistivity of thealloy films is lower than that of original bulk alloy. Incorporation of alloying elements Cr and Al in copper films results in a decrease in the grain size, while the heightofsurfaceroughnessand adhesion of the films to the glass-ceramic substrates is considerably improved. The thermal stability of thin-film components prepared on the basis of the investigated alloy is high. M V Belous et al, Izv VUZFiz, No 8, 1971,52-56 (in Russian). 30 732. Structure and electrical properties of cerium dioxide films. (USSR) Structure of cerium dioxide films was investigated by electron diffraction and electron transmission microscopy. The CeO, films were prepared by cathodic sputtering, thermal evaporation and plasma-arc spraying. Cathodic sputtering of cerium wzas carried out in oxygen at 10-l to 5 x I 0e2 torr, current density of 1.5 to 2 mA/cm” and voltage of 1 to 1.5 kV with a deposition rate of 20 to 30 A/min. CeO, powder was thermally evaporated from tungsten boats on glass ceramics substrates in vacuum below IO-” torr. The condensation rate was 8 to 10 &sec and good adhesion was obtained at substrate temperature above 200°C. N N Zaichkin, Zzv VUZ Fiz, No 8, 197 1, 133-I 34 (in Russian). 30 733. Influence of electric field on the crystallization of amorphous selenium. (USSR) Influence of electric field and illumination on the crystallization of selenium amorphous films is investigated. Selenium films 200 to 2000 8, thick were vacuum deposited at 5 z lo-” torr from a molecular beam on to freshly cleaved mica or mica covered with carbon. It is found that preferred growth of spherulites along the lines of the electric field takes place. The direction of the preferred growth depends on the substrate material. On mica substrates, growth opposite to the field occurs, while on carbon substrates the growth is observed in the direction of the field. The action of the electric field is explained by induction of the electric current in the selenium film, the hole current on the mica substrate, and the electron current on thin carbon film. The crystal faces, to which charges are flowing, have the highest growth rate. It is probable that this effect is connected with the enhancement of molecule mobility due to energy released on annihilation of opposite charges. S A Belan et al, Izv VU2 Fiz, No 6, I97 1, 106- 109 (in Russian). 30 734. A thin-film transistor with an interlayer at the semiconductorinsulator interface. (Czechoslovakia). An analysis of the properties of the semiconductor-insulator interface influencing the parameters of CdSe thin-film field-effect transistors is presented. It is shown that with normal vacuum preparation methods at 1O-5 torr, a certain concentration of the surface-adsorbed oxygen from the residual gas on the CdSe film being existent, the 243
abstracts
723-734
couple type TVB manufactured for measurement of high-frequency currents can be used for measurement of absolute pressures in the range of 1.33to 1330 Pa with a relative average square error of 5 per cent. An apparatus with McLeod gauge for calibration of the thermocouple gauge is described. E G Baldin et al, Izmerit Tekh, No 12, 197 I, 42-43 (in Russian). 22 723. Calibration of thermal-conductivity vacuum gauges for different gases. (USSR) A formula is derived, which describes the calibration curves for different gases and their mixtures, for a thermocouple vacuum gauge type VSB-1 operated in the regime of constant temperature. A A Birsbert, Izmerit Tel&, No 7, 197 1, 75 (in Russian). 28. HEATING
EQUIPMENT
AND THERMOMETERS
28 724. Tungsten-rhenium thermocouple for oxidation ambients. (USSR) It is shown that thermocouples of tungsten-rhenium alloys with protective coating of vacuum deposited iridium film and alundum layer can be used for measurement of temperature up to 2400°C in oxidation ambients. I N Akimovich et al, lzmerit Tekh, No 7, 197 I, 76 (in Russian). 28 725. Device for sample heating in a vacumn system. (USSR) A quartz glass device in a vacuum system for heating small samples of materials in vacuum by an external furnace or by induction heating up to I lOO”C, is described. G A Mochalov, Zavodsk Lab, 37 (8), 1971, 995-996 (in Russian).
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
30 726. A triode-rf-sputtering system for film deposition in the lo-” torr range. (Germany) Sputtering modules with low-voltage arcs allow high-rate sputtering of metals, even at pressures below one micron. In the system described, the sputtering chamber has the same potential as the anode and the plasma arc is conducted to the target by a static magnetic field. With an rf-induced negative target voltage dielectric films may be produced since total coverage of the anode with the sputtering material is impossible. Also interference between the rf- and arccurrents are presented. With the same system, reactively sputtered dielectric films such as SiOz, Al,O,may be produced. 0 Sagev, Vakuum-Technik, 20 (8), Dee 1971, 225-23 1 (in German). 30 727. Reactive evaporation in ionized gases. (Germany) Evaporation techniques are reviewed and some problems considered. A new method is described in which reactive evaporation is carried out in ionized gases, the reaction gas being ionized in a discharge tube with high current density and emerging through a nozzle in the wall of the tube directly into the high vacuum region. Parameters for the production of SiO,, SiO,N, and TiOz films are presented as well as their optical properties, stability, structure, and internal stress. All films proved to be very stable, showed smooth surfaces and an x-ray amorphous structure. The SiO, films were free of absorptance within the accuracy of measurement at least down to 190 nm and had the same refractive index as bulk quartz glass. On unheated substrates, practically non-absorbing TiO, films were obtained with refractive indices up to 2.3. W Heitmann, Vakuum-Technik, 21 (I), Feb 1972, 1-11 (in German). 30 728. Energy spectra of the products of cathodic sputtering in the bombardment of metals by light ions. (USSR) Energy spectra are calculated taking account of the successive collisions of a primary ion with atoms of crystal lattice. Good agreement with experimental data is obtained. V I Veksler, Izv AN SSSR Ser Fiz, 3.5 (2), 1971, 379-383 (in Russian). 30 729. Interdiffusion and compound formation in thin films of Pd or Pt on Si single crystals. (Germany) Transmission electron microscopy techniques were used to observe compound formation during diffusion in couples composed of thin films of Pd or Pt on Si single crystal wafers. Platinum films were deposited by vacuum evaporation using an electron gun, palladium
films were evaporated from a tungsten filament. In Pt-Si diffusion couples three compounds Pt,Si, Pt$i and PtSi were found. For Pd-Si diffusion couples the major phase was Pd,Si with only small amounts of PdSi formed after vacuum annealing. (USA) J Drobek et al, Whys Stat Sal (a), 8 (I), Nov 1971,243-248. 30 730. Synthesis of highly oriented cadmium and zinc chalcogenide films of definite structure. (Hungary) The effects of the degree of deviation from thermodynamic cquilibrium, evaporator construction, and nature of the orienting substrate, on the growth of monocrystalline cadmium and zinc chalcogenide films are investigated during condensation in a vacuum of lop4 to 10e5 torr. Quartz ampoules of the Knudsen cell type with one effusive aperture (1-2 mm) or 100 apertures (0.2 mm) were used as evaporators. (USSR) I P Kalinkin et al, Proc Inter Canf’Ph~s Chem Semicon Heterojunc Layer Strut, 3, Akademiai Kiada Budapest 1971, 153- 162. 30 731. Some properties of vacuum evaporated films of aluminium, nickel, cobalt, copper and Cu-Cr-Al alloy. (USSR) Electrical properties, adhesion, thermal stability, weldability and structure of vacuum evaporated films of Al, Ni, Co, Cu and Cu-Cr-Al alloy are investigated. The films were evaporated from a resistance heated tungsten evaporator in vacuum at 5 x IO-” to 1 :’ 10e5 torr in a system with efficient liquid nitrogen traps. The average condensation rate was 5 to 10 &sec. Structure of the fihns was investigated in an electron microscope. It is shown that electrical resistivity of the pure metal films is higher than that of the original bulk materials while the resistivity of thealloy films is lower than that of original bulk alloy. Incorporation of alloying elements Cr and Al in copper films results in a decrease in the grain size, while the heightofsurfaceroughnessand adhesion of the films to the glass-ceramic substrates is considerably improved. The thermal stability of thin-film components prepared on the basis of the investigated alloy is high. M V Belous et al, Izv VUZFiz, No 8, 1971,52-56 (in Russian). 30 732. Structure and electrical properties of cerium dioxide films. (USSR) Structure of cerium dioxide films was investigated by electron diffraction and electron transmission microscopy. The CeO, films were prepared by cathodic sputtering, thermal evaporation and plasma-arc spraying. Cathodic sputtering of cerium wzas carried out in oxygen at 10-l to 5 x I 0e2 torr, current density of 1.5 to 2 mA/cm” and voltage of 1 to 1.5 kV with a deposition rate of 20 to 30 A/min. CeO, powder was thermally evaporated from tungsten boats on glass ceramics substrates in vacuum below IO-” torr. The condensation rate was 8 to 10 &sec and good adhesion was obtained at substrate temperature above 200°C. N N Zaichkin, Zzv VUZ Fiz, No 8, 197 1, 133-I 34 (in Russian). 30 733. Influence of electric field on the crystallization of amorphous selenium. (USSR) Influence of electric field and illumination on the crystallization of selenium amorphous films is investigated. Selenium films 200 to 2000 8, thick were vacuum deposited at 5 z lo-” torr from a molecular beam on to freshly cleaved mica or mica covered with carbon. It is found that preferred growth of spherulites along the lines of the electric field takes place. The direction of the preferred growth depends on the substrate material. On mica substrates, growth opposite to the field occurs, while on carbon substrates the growth is observed in the direction of the field. The action of the electric field is explained by induction of the electric current in the selenium film, the hole current on the mica substrate, and the electron current on thin carbon film. The crystal faces, to which charges are flowing, have the highest growth rate. It is probable that this effect is connected with the enhancement of molecule mobility due to energy released on annihilation of opposite charges. S A Belan et al, Izv VU2 Fiz, No 6, I97 1, 106- 109 (in Russian). 30 734. A thin-film transistor with an interlayer at the semiconductorinsulator interface. (Czechoslovakia). An analysis of the properties of the semiconductor-insulator interface influencing the parameters of CdSe thin-film field-effect transistors is presented. It is shown that with normal vacuum preparation methods at 1O-5 torr, a certain concentration of the surface-adsorbed oxygen from the residual gas on the CdSe film being existent, the 243