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Study of electrode products emitted by vacuum arcs in form of molten metal particles
Classified
abstracts
1039-l
047
Theoretical results on the influence of the second and third harmonic frequencies on parameters of three-dimensional mass spectrometer are presented and compared with the experimental data. E P Sheretov et al, Rep of Ryazan Radiotech Inst, No 35, 1973, 54-61 (in Russian). 22
1039. On some analytical characteristics of three-dimensional quadrupole mass spectrometer. (USSR) The dependences of resolution, sensitivity and mass peak shape on the conditions of injection of ionizing electron beam and modes of operation of the three-dimensional quadrupole mass spectrometer are considered. V A Zenkin and B I Kolotilin, Rep of Ryazan Radiotech Inst, No 35, 1973, 61-71 (in Russian).
24. VALVES 24 1040. A series of very high-vacuum valves with electric heaters for nominal apertures of 10,20,30,50,100,150 and 200 nm. (USSR) On the basis of prolonged experience with a very high-vacuum valve designed for a nominal aperture of 150 mm diameter, a series of analogous valves for nominal apertures of 10, 20, 30, 50, 100, 150, and 200 mm diameter is proposed. The degree of vacuum envisaged is lo-” torr. The tests carried out on these valves involve repeated heating cycles to 400°C and about 1000 openings and closings of the valve. The principal material is stainless chromium-nickel steel and the sealing material is in most cases copper. By a special shaping of the moving parts the creation of undue local stresses (a constant danger in such vacuum elements) is largely avoided. Tables giving the constructional data and working chara%e&stics are provided. I R Kirichek et al, Physico-Technical Institute, Academy of Sciences of the Ukrainian SSR, Series High-Vacuum
Questions of Atomic Science and Technology, Physics and Technology, No. 1 (I), Khar’kov
(1973).
25. BAFFLES
TRAPS AND REFRIGERATION
EQUIPMENT
25 1041. A vacuum trap. (USSR) In the vacuum trap here proposed the slide (gate) is made in the form of two metal disc valves with toothed wheels placed between them; on rotating the shafts of these wheels the distance between the discs may be varied. This arrangement improves the reliability of the metal/metal contacts and hence the efficiency of the whole trap. Fine adjustment is effected by providing the toothed wheels with a drive furnished with microswitches, which makes precise siting of the valve components simple and rapid. When the gap between the metal plates is finally closed the system rests in a very stable equilibrium until it is again brought into motion via the switch system. A A Denmukhamedov and A A Postnikov, Soviet Patent, class F 16 k, 31153, No 410209, Russian).
claimed
29 May
1972, publd
24 April
1974 (in
26. AUTOMATIC PROTECTIVE AND CONTROL EQUIPMENT 26 1042. Safety device for a rough vacuum line. (USSR)
An improved form of safety device intended to prevent the breakthrough of the atmosphere either from the pumping end or from the objects being evacuated to a rough vacuum line is described. The normal membrane of the sensitive element is replaced by two almost inertia-free electrical-discharge sensors, while the gas flow is retarded by means of two ejection devices. The effect of this modification (contrasting it with existing protective devices) lies in increasing the speed and reliability of execution of the necessary protective measures -the shutting of valves, the disconnection of electrical equipment, etc. If instead of a sudden break a relatively slow but serious leak occurs, the protective system also operates in a gradual manner so that surges are avoided. A P Besschetnov and T Ya Gus’kova, Soviet Patent, class H 01 f, 13130, F 16 k, 17142, No 369646, claimed 4 December 1970, publd 8 August 1973 (in Russian).
28. HEATING
EQUIPMENT
AND THERMOMETERS
28 1043. Rotational Raman interferometric technique to measure gas temperatures. (USA) The rotational Raman interferogram profile of a gas is shown to provide the basis for a sensitive, remote measurement of the gas temperature. The technique is illustrated by means of a feasibility study of a laser radar atmospheric temperature probe. Errors in the measurement are discussed and suggestions given for an improved temperature probe. R L Armstrong, Appl Opt, 14 (2), 1975,383-387. 28
1044. Multiposition machine for carrying out high-temperature tests on various materials in vacua. (USSR) The multiposition device here pioposed for the high-temperature mechanical testing of various materials in vacua comprises a large number of active and passive clamps (for fixing the samples) set around a circular base, together with a heating system equally embracing all these positions. The base may be rotated about its axis, so improving the accuracy of experimental data. The vacuum installation and heating circuit associated with the system are of conventional form. Each sample is moved in turn into a position enabling mechanical stresses of various kinds to be applied to it. By subjecting a series of samples taken from the same batch to successive mechanical (e.g. tensile) tests, good statistical results may be expected. N P Drozd et al, Souiet Patent, class G 01 p, 3/18, No 399761, c/aimed 6 January 1970, pub/d 13 Februury 1974 (in Russian).
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
2n 1045. Field effect conductance modulation in vacuum-evaporated amorphous silicon films. (USA) Electron-beam vacuum-deposited amorphous silicon films were deposited at controlled rates from 3.1 to 5.6 A/s onto Si-SiO, substrates followed by a 4-h 400°C in situ anneal. The high-temperature activation energy for these films has an average value of 0.79 eV and is relatively independent of the deposition rate. The room-temperature resistivity varies from 3 x 10’ !J cm at a 5.6 A/s rate to 5.7 x IO7 fl cm at 3.1 A/s. The pre-exponential factor has an average value of 7 x lo-’ n cm and is independent of the deposition rate. A change in source-drain current due to a transverse electric field was observed at room and elevated temperatures for both positive and negative gate voltages. The results indicate that the Fermi level is not pinned near midgap and that the density of localized states near the Fermi level is not pinned near midgap and that the density of localized states near the Fermi level is nearly uniform for *0.40 above and below midgap. Calculations indicate that the density of localized states near the Fermi level is about 10z0/cm3 eV and decreases slightly as the rate is decreased. G W Neudeck and A K Malhotra, J Appl Phys, 46 (l), 1975, 239-246. _I”
30 1046. Study of electrode products emitted by vacuum arcs in form of molten metal narticles. (USA) The electrode-products kmittdd by vacuum arcs in the form of molten metal particles were studied for Au, Pd, and Mg in the current range 2-6 A, The study includes the size distribution of these molten metal particles, the volume carried by these particles versus the volume carried by the metal vapour, and the velocity distribution of these particles. It was found that the ratio ofvolumes carried by the particles and the vapour is greatly dependent on the cathode material. T Utsumi and J H English,J Appl Phys, 46 (l), 1975,126-131. 30 1047. The origin of internal stress in low-voltage sputtered tungsten films. (USA) The internal stress can be of importance in the tungsten metallization process used for the fabrication of large-scale integrated circuits. The present work is an extension of an earlier study on the dependence of the stress in low-voltage triode sputtered tungsten films upon deposition conditions and substrate materials. As a-function of film thickness, 339
abstracts
1039-l
047
Theoretical results on the influence of the second and third harmonic frequencies on parameters of three-dimensional mass spectrometer are presented and compared with the experimental data. E P Sheretov et al, Rep of Ryazan Radiotech Inst, No 35, 1973, 54-61 (in Russian). 22
1039. On some analytical characteristics of three-dimensional quadrupole mass spectrometer. (USSR) The dependences of resolution, sensitivity and mass peak shape on the conditions of injection of ionizing electron beam and modes of operation of the three-dimensional quadrupole mass spectrometer are considered. V A Zenkin and B I Kolotilin, Rep of Ryazan Radiotech Inst, No 35, 1973, 61-71 (in Russian).
24. VALVES 24 1040. A series of very high-vacuum valves with electric heaters for nominal apertures of 10,20,30,50,100,150 and 200 nm. (USSR) On the basis of prolonged experience with a very high-vacuum valve designed for a nominal aperture of 150 mm diameter, a series of analogous valves for nominal apertures of 10, 20, 30, 50, 100, 150, and 200 mm diameter is proposed. The degree of vacuum envisaged is lo-” torr. The tests carried out on these valves involve repeated heating cycles to 400°C and about 1000 openings and closings of the valve. The principal material is stainless chromium-nickel steel and the sealing material is in most cases copper. By a special shaping of the moving parts the creation of undue local stresses (a constant danger in such vacuum elements) is largely avoided. Tables giving the constructional data and working chara%e&stics are provided. I R Kirichek et al, Physico-Technical Institute, Academy of Sciences of the Ukrainian SSR, Series High-Vacuum
Questions of Atomic Science and Technology, Physics and Technology, No. 1 (I), Khar’kov
(1973).
25. BAFFLES
TRAPS AND REFRIGERATION
EQUIPMENT
25 1041. A vacuum trap. (USSR) In the vacuum trap here proposed the slide (gate) is made in the form of two metal disc valves with toothed wheels placed between them; on rotating the shafts of these wheels the distance between the discs may be varied. This arrangement improves the reliability of the metal/metal contacts and hence the efficiency of the whole trap. Fine adjustment is effected by providing the toothed wheels with a drive furnished with microswitches, which makes precise siting of the valve components simple and rapid. When the gap between the metal plates is finally closed the system rests in a very stable equilibrium until it is again brought into motion via the switch system. A A Denmukhamedov and A A Postnikov, Soviet Patent, class F 16 k, 31153, No 410209, Russian).
claimed
29 May
1972, publd
24 April
1974 (in
26. AUTOMATIC PROTECTIVE AND CONTROL EQUIPMENT 26 1042. Safety device for a rough vacuum line. (USSR)
An improved form of safety device intended to prevent the breakthrough of the atmosphere either from the pumping end or from the objects being evacuated to a rough vacuum line is described. The normal membrane of the sensitive element is replaced by two almost inertia-free electrical-discharge sensors, while the gas flow is retarded by means of two ejection devices. The effect of this modification (contrasting it with existing protective devices) lies in increasing the speed and reliability of execution of the necessary protective measures -the shutting of valves, the disconnection of electrical equipment, etc. If instead of a sudden break a relatively slow but serious leak occurs, the protective system also operates in a gradual manner so that surges are avoided. A P Besschetnov and T Ya Gus’kova, Soviet Patent, class H 01 f, 13130, F 16 k, 17142, No 369646, claimed 4 December 1970, publd 8 August 1973 (in Russian).
28. HEATING
EQUIPMENT
AND THERMOMETERS
28 1043. Rotational Raman interferometric technique to measure gas temperatures. (USA) The rotational Raman interferogram profile of a gas is shown to provide the basis for a sensitive, remote measurement of the gas temperature. The technique is illustrated by means of a feasibility study of a laser radar atmospheric temperature probe. Errors in the measurement are discussed and suggestions given for an improved temperature probe. R L Armstrong, Appl Opt, 14 (2), 1975,383-387. 28
1044. Multiposition machine for carrying out high-temperature tests on various materials in vacua. (USSR) The multiposition device here pioposed for the high-temperature mechanical testing of various materials in vacua comprises a large number of active and passive clamps (for fixing the samples) set around a circular base, together with a heating system equally embracing all these positions. The base may be rotated about its axis, so improving the accuracy of experimental data. The vacuum installation and heating circuit associated with the system are of conventional form. Each sample is moved in turn into a position enabling mechanical stresses of various kinds to be applied to it. By subjecting a series of samples taken from the same batch to successive mechanical (e.g. tensile) tests, good statistical results may be expected. N P Drozd et al, Souiet Patent, class G 01 p, 3/18, No 399761, c/aimed 6 January 1970, pub/d 13 Februury 1974 (in Russian).
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
2n 1045. Field effect conductance modulation in vacuum-evaporated amorphous silicon films. (USA) Electron-beam vacuum-deposited amorphous silicon films were deposited at controlled rates from 3.1 to 5.6 A/s onto Si-SiO, substrates followed by a 4-h 400°C in situ anneal. The high-temperature activation energy for these films has an average value of 0.79 eV and is relatively independent of the deposition rate. The room-temperature resistivity varies from 3 x 10’ !J cm at a 5.6 A/s rate to 5.7 x IO7 fl cm at 3.1 A/s. The pre-exponential factor has an average value of 7 x lo-’ n cm and is independent of the deposition rate. A change in source-drain current due to a transverse electric field was observed at room and elevated temperatures for both positive and negative gate voltages. The results indicate that the Fermi level is not pinned near midgap and that the density of localized states near the Fermi level is not pinned near midgap and that the density of localized states near the Fermi level is nearly uniform for *0.40 above and below midgap. Calculations indicate that the density of localized states near the Fermi level is about 10z0/cm3 eV and decreases slightly as the rate is decreased. G W Neudeck and A K Malhotra, J Appl Phys, 46 (l), 1975, 239-246. _I”
30 1046. Study of electrode products emitted by vacuum arcs in form of molten metal narticles. (USA) The electrode-products kmittdd by vacuum arcs in the form of molten metal particles were studied for Au, Pd, and Mg in the current range 2-6 A, The study includes the size distribution of these molten metal particles, the volume carried by these particles versus the volume carried by the metal vapour, and the velocity distribution of these particles. It was found that the ratio ofvolumes carried by the particles and the vapour is greatly dependent on the cathode material. T Utsumi and J H English,J Appl Phys, 46 (l), 1975,126-131. 30 1047. The origin of internal stress in low-voltage sputtered tungsten films. (USA) The internal stress can be of importance in the tungsten metallization process used for the fabrication of large-scale integrated circuits. The present work is an extension of an earlier study on the dependence of the stress in low-voltage triode sputtered tungsten films upon deposition conditions and substrate materials. As a-function of film thickness, 339