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1409. Influence of alkali metal impurities on field and photo-field electron emission from silicon tips
Classified abstracts 1398-1411 generation of deuterium neutrals in the discharge by double charge transfer are described S V Mirnov and I B Semenov, Dtagnostws of Plasma, Coil, No 3, Atomizdat Moscow 1973, 24-27 (in Russian). 18 1398. Spectroseopical measurement of plasma parameters in a coaxial injector. (USSR) A spectroscoplcal method for measurement of plasma density and temperature m a coaxial plasma rejector is described The spectra emitted by carbon and oxygen ions of plasma in the visible range are measured with the aid of a diffraction spectrograph combined with an electron-optical amplifier. V A Abramov et al, Diagnostics of Plasma, Coil, No 3, Atomizdat Moscow 1973, 27-31 (in Russian). 18 1399. Measurement of electrical fields in turbulent plasma by Stark broadening of hydrogen lines. (USSR) Intensity of electrical fields caused by 1on-sound oscillations at turbulent heating of plasma is measured with the aid of Stark broadening of hydrogen hnes The experiments were performed in a vacuum chamber. E K Zavoyskiy et al, Diagnostws of Plasma, Coil, No 3, Atomizdat Moscow 1973, 41~14 (m Russian). 18 1400. Measurement of the degree of turbulence of electrostatic oscillations in eollisionless plasma by Stark broadening of spectral hydrogen lines by the method of high-speed electron-optical speetro-chronography. (USSR) A method of high-speed electron-optical spectro-chronography was used for measurement of the degree of turbulence of electrostatic oscillations m plasma by the Stark broadening of hydrogen lines The inttml pressure of hydrogen was 5 × 10 -a to 10 -2 torr. S P Zagorodnikov et al, Diagnostics of Plasma, Coil, No 3, Atomizdat Moscow 1973, 45-55 (m Russian) 18 1401. Experimental determination of parameters of turbulent plasma by Stark broadening of spectral lines. (USSR) Using a spectrograph, the light emitted from a discharge in hydrogen at pressures of 2 ~< 10 -4 to 10-a tort in a toroldal Tokamak installation is investigated. Electric fields in pulsations in plasma are determined from the Stark broadening of hydrogen spectral lines. V A Vershkov et al, Diagnostws of Plasma, Coil, No 3, Atormzdat Moscow 1973, 55-59 (in Russian). 18 1402. Investigation of ion temperature in Tokamak installations with accounting of space distribution of plasma parameters. (USSR) Distribution of intensity of spectral lines and their Doppler broadenlng along the plasma column is investigated in a Tokamak installation at initial hydrogen pressure of 3 3 × 10 -4 to 7 × l0 -'~ tort. The temperature of ions in the discharge was determined. D A Scheglov, Diagnostws of Plasma, Coil, No 3, Atomizdat Moscow 1973, 65-68 (in Russian). 18 1403. Utilization of double electron-optical intensifier for investigation of pulsed plasma-beam discharge. (USSR) A double electron-optical intensifier was used for investigation of dynamics of a plasma-beam discharge with duration of 0.1 to 0 3 p.sec in H2, He and Ar at pressures of 4 × 10 -4 to 10 -3 torr. Energy of ions and intensities of low- and high-frequency regular stochastic fields are determined from measurement of spectral hne widths. I A Bezyazychnyy et al, Diagnostics of Plasma, Coil, No 3, .4tomizdat Moscow 1973, 5943 (in Russian). 18 1404. Spectroscopical investigation of rotating plasma. (USSR) Velocity of rotation of plasma in a discharge in hydrogen at pressure of 3 × 10 -a torr is determined with the aid of measurement of Doppler shift of lines The experiments were performed in a cylindrical vacuum chamber with inner coils for generation of magnetic field. B Vilner, Diagnostics of Plasma, Coil, No 3, Atomtzdat Moscow 1973, 68-72 (in Russian). 18 1405. On secondary emission and photoemission properties of antimony-cesium photocathode. (USSR) Photoemission and secondary electron emission properties of semitransparent Sb-Rb-Cs photocathodes are investigated. The photo-
cathodes have been prepared by treatment of antimony films with transparence of 5 to 20~o with rubidium and cesium at activation temperature of 180 to 220°C. The integral sensitivity of photocathodes was about 80 #A/lm and it increased to 100 #A/lm after sensitization with oxygen. Spectral sensitivity at the maximum (at wavelength of 400 to 50 t~m) was about 100 mA/W (the quantum yield 0.254).28). The threshold of photoeffect was at 1 6 eV and the value of electron affinity was estimated to 0. I eV. The maximum value of the coefficient of secondary electron emission was 16 to 20 at primary electron energy of 1.2 to 1.6 keV The coeffioent of secondary electron emission of sensitized photocathodes was 20% higher. L M Kulova et al, Rep of North Caucasian Ore Mining Inst, No 33, 1972, 278-279 (in Russian). 18 1406. Some regularities of motion of excited electrons in semiconductor photocathodes. (USSR). Processes of dissipation of energy of excited electrons in semiconductor emitters are considered with account of Coulomb interactions with conductiwty electrons. It is shown that scattering on conductivity electrons does not cause slgmficant losses of energy of exoted electrons. S K Kulov, Rep of North Caucasian Ore Mining Inst, No 33, 1972, 275-278 (m Russ:an). 18 1407. Features of measuring instruments for testing of field electron cathodes. (USSR) Requirements of measuring instruments for investigahon of voltampere characteristics of field electron emitters in both direct current and pulsed regimes and of thew useful life are considered. Some measuring circuits are described and the accuracy of measurement is evaluated. B V Bondarenko et al, Rep ofPhys-tech In~t of Radlotech and Electronics, Part 2, 1973, 33-39 (m Russian) 18 1408. Energy of electrons emitted from metal surface heated by pulsed irradiation. (USSR) A time-of-flight method is used for determination of energy of electrons emitted from (100) Mo surface irradiated with a laser beam with energy 10 -2 J and pulse duration 10 -7 sec. The characteristic energy of emitted electrons was found to be 0.25 eV which indicates a thermal character of observed electron emission B V Bondarenko et al, Rep of Moscow Phys-tech lnst of Radiotech and Electronics, Part 2, 1973, 27-32 (m Russian). 18 1409. Influence of alkali metal impurities on field and photo-field electron emission from silicon tips. (USSR) The influence of alkali metal impurities present in the volume and of sodium deposited from molecular beam on field and photo-field emmslon of p-type silicon tips is investigated in a glass apparatus at residual gas pressure of 10 -9 torr. V F Bibik and A A Dadykin, lzv A N SSSR Ser Fiz, 37 (12), 1973, 2625-2629 (in Russian) 18 1410. Mieroplasma breakdown of semiconductor field cathodes. (USSR) Kinetics of formatnon of the photo-field emission current from single crystal p-Ge and CdS field cathodes is mvestlgated in a vacuum of 5 ~ 10 - 9 torr on apphcation of single voltage pulses to the emitter. Presence of rectangular bursts in the emission current ~s explained by microplasma breakdown of semiconductor field cathodes. P G Shlyaldltenko et al, Izv A N SSSR Ser Fiz, 37 (12). 1973, 26302632 (in Russian). 18:30 1411. Cold electron emission from cathodes based on dispersed molybdenum films. (USSR) Emission characteristics of dispersed molybdenum films are investigated in sealed-off glass experimental devices and a high-vacuum metal apparatus. The films have been condensed at room temperature on glass and sapphire substrates with previously evaporated film metallic contacts with thickness of about 1000 ,~ and forming a gap with width of 20 ~.m and length of 2 to 3 mm. Wire masks or photochemical etching was used for preparation of such gaps. A tungsten wire with welded molybdenum crystallite was used as a source of molybdenum vapours. Molydbenum film thickness was monitored by a quartz resonator and by measurement of electrical resistance of
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cathodes have been prepared by treatment of antimony films with transparence of 5 to 20~o with rubidium and cesium at activation temperature of 180 to 220°C. The integral sensitivity of photocathodes was about 80 #A/lm and it increased to 100 #A/lm after sensitization with oxygen. Spectral sensitivity at the maximum (at wavelength of 400 to 50 t~m) was about 100 mA/W (the quantum yield 0.254).28). The threshold of photoeffect was at 1 6 eV and the value of electron affinity was estimated to 0. I eV. The maximum value of the coefficient of secondary electron emission was 16 to 20 at primary electron energy of 1.2 to 1.6 keV The coeffioent of secondary electron emission of sensitized photocathodes was 20% higher. L M Kulova et al, Rep of North Caucasian Ore Mining Inst, No 33, 1972, 278-279 (in Russian). 18 1406. Some regularities of motion of excited electrons in semiconductor photocathodes. (USSR). Processes of dissipation of energy of excited electrons in semiconductor emitters are considered with account of Coulomb interactions with conductiwty electrons. It is shown that scattering on conductivity electrons does not cause slgmficant losses of energy of exoted electrons. S K Kulov, Rep of North Caucasian Ore Mining Inst, No 33, 1972, 275-278 (m Russ:an). 18 1407. Features of measuring instruments for testing of field electron cathodes. (USSR) Requirements of measuring instruments for investigahon of voltampere characteristics of field electron emitters in both direct current and pulsed regimes and of thew useful life are considered. Some measuring circuits are described and the accuracy of measurement is evaluated. B V Bondarenko et al, Rep ofPhys-tech In~t of Radlotech and Electronics, Part 2, 1973, 33-39 (m Russian) 18 1408. Energy of electrons emitted from metal surface heated by pulsed irradiation. (USSR) A time-of-flight method is used for determination of energy of electrons emitted from (100) Mo surface irradiated with a laser beam with energy 10 -2 J and pulse duration 10 -7 sec. The characteristic energy of emitted electrons was found to be 0.25 eV which indicates a thermal character of observed electron emission B V Bondarenko et al, Rep of Moscow Phys-tech lnst of Radiotech and Electronics, Part 2, 1973, 27-32 (m Russian). 18 1409. Influence of alkali metal impurities on field and photo-field electron emission from silicon tips. (USSR) The influence of alkali metal impurities present in the volume and of sodium deposited from molecular beam on field and photo-field emmslon of p-type silicon tips is investigated in a glass apparatus at residual gas pressure of 10 -9 torr. V F Bibik and A A Dadykin, lzv A N SSSR Ser Fiz, 37 (12), 1973, 2625-2629 (in Russian) 18 1410. Mieroplasma breakdown of semiconductor field cathodes. (USSR) Kinetics of formatnon of the photo-field emission current from single crystal p-Ge and CdS field cathodes is mvestlgated in a vacuum of 5 ~ 10 - 9 torr on apphcation of single voltage pulses to the emitter. Presence of rectangular bursts in the emission current ~s explained by microplasma breakdown of semiconductor field cathodes. P G Shlyaldltenko et al, Izv A N SSSR Ser Fiz, 37 (12). 1973, 26302632 (in Russian). 18:30 1411. Cold electron emission from cathodes based on dispersed molybdenum films. (USSR) Emission characteristics of dispersed molybdenum films are investigated in sealed-off glass experimental devices and a high-vacuum metal apparatus. The films have been condensed at room temperature on glass and sapphire substrates with previously evaporated film metallic contacts with thickness of about 1000 ,~ and forming a gap with width of 20 ~.m and length of 2 to 3 mm. Wire masks or photochemical etching was used for preparation of such gaps. A tungsten wire with welded molybdenum crystallite was used as a source of molybdenum vapours. Molydbenum film thickness was monitored by a quartz resonator and by measurement of electrical resistance of
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