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128. Ion cyclotron resonance power absorption: Collision frequencies for CO2+, N2+ and H2+ ions in their parent gases
Classified
abstracts
127-138
readily disintegrate, and the metallic components may be recovered by conventional techniques. 2 I Braun et al, USSR Patent No 281662, trppl3rd Jan 1969, publd 23rd Dee 1970. 33.
GENERAL PHYSICS AND ELECTRONICS
33 127. Method of stretching disc grids. (USSR) A method of stretching disc grids so as to ensure a uniform disposition of the grid material without distorting the underlying discs is described. The method is based on the creation of a special clamping system which allows the grid to undergo deformation in a radial direction only. To this end the clamps are made in the form of a set of contiguous sectors movable with respect to one another and symmetrically disposed relative to the axis of the grid. The degree of uniformity increases with increasing number of sectors employed. Experience suggests sixteen sectors as a number convenient for most practical purposes. Yu I Abramskii and V A Nikitinskii, USSR Patent No 272440, appl 1st Aug 1966, publd 11th Sept 1970. 128. Ion cyclotron resonance power absorption: for CO,+, N,+ and H,+ ions in their parent gases.
Collision (USA)
33 frequencies
Calculations for ion cyclotron resonance (ICR) gives excellent agreement for instantaneous power absorption with experiment at all pressures. The absorption at resonance initially increases linearly with time and at high pressures levels off at a constant value at saturation. An expression is derived for the average kinetic energy of an ion at saturation in the steady-state limit. Pulsed ICR techniques are used to obtain the instantaneous power absorption curves for N,+, CO,+ and HZ+ ions in their parent gases as a function of pressure. From these data, the momentum transfer rate constants and their dependence on ion kinetic energy are calculated. Values are given at 293’ K. The values are considered in terms of polarization theory. WTHuntress,JChemPhys,55(5), 1stSept 1971,2146-2155. 129. Method for estimating excess kinetic energy of ionization in a pulsed ion source. (USA)
33 products
A pulsed ion source in a 60 magnetic sector mass spectrometer was used to study the decay of thermal ions and compared with calculations. An increase in ion decay observed for several positive and negative ions is attributed to kinetic energy in excess of their ambient thermal energy. Consideration is given to experimental conditions and particle condition effects. I Platzner et al, J Chem Phys, 55 (5), 1st Sept 197 I, 2276-2278. 33
energy-loss spectrum of oxygen. (USA) The apparatus used consisted of an ion source and mass analyzer followed by an energy selector, a collision chamber, a second energy selector and a detector. It was designed to study the energy lost by ions with initial energies of 50 eV-5 keV. The oxygen atom was studied by measuring the kinetic energy lost by 100 eV-4 keV H+, H,+ and He+ which are inelastically scattered. The SchumannRunge continuum appears to be the result of at least two different transitions. The optically forbidden Hertzberg continuum is observed in all of the ion-impact spectra. Triplet-singlet transitions are the most intense features of the H,+ and He+ impact spectra. J H Moore, J Chem Phys, 55 (6), 15th Sept 1971,2760-2764. 33 131. Vapour-phase growth of several III-V compound semiconductors. (USA) A review is presented of a vapour-phase growth method that has been developed for the synthesis of a broad spectrum of 111-V compounds. The predominant feature of this technique is the use of gases as the source chemicals, thereby providing improved control of the chemical composition, homogeneity, crystalline perfection, and impurity concentrations and distributions of the epitaxial layers. As a result, a number of notable advances have been made with respect to the material properties and device utilization of several 111-V compounds. The chemistry of the deposition processes was studied by means of a mass spectrometer coupled to the vapour-phase growth system. Results of these studies are presented and discussed. J J Tietjen et al, J Vat Sri Tech&, 8 (5), Sept/Oct 1971, S5-SI I. 33 132. Applications of ion implantation for new device concepts. (USA) Ion-implantation doping offers many potential advantages over con130. Ion-impact
38
ventional techniques such as ditfusion and epitaxial growth for the fabrication of new devices. The general features of ion implantation are reviewed. Examples from silicon-device fabrication are chosen to illustrate the manner in which ion-implantation doping complements diffusion and epitaxial growth to provide device architects with increased flexibility in device design. B L Crowder, J Vat Sci Technol, 8 (5), Sept/Ort 191I, S7 I -S75. 33 133. Reflection of slow electrons from (110) and (111) faces of tungsten
single crystal. (USSR) Energy dependence of the coefficient of elastic reflection of secondary electron emission and the coefficient of true secondary inelastically reflected electrons for the clean and contaminated (110) and (111) faces of tungsten single crystal is investigated in the energy range of primary electrons of 1 to 30 eV at normal beam incidence. The experiments have been performed in sealed glass devices. A Myers electron gun with indirectly heated lanthanum hexaboride cathode was used as a source of a monoenergetic slow electron beam. For analysis of the energy distribution of secondary electrons a spherical capacitor was employed. Barium and titanium getters reduced the pressure in the sealed devices to 1% 10 !’torr. It is found that the coefficient of reflection of the clean (110) face is 0.08 at energy of 1 eV, it reaches a maximum of 0.34 at energy of 3.3 eV and decreases at higher energies. Around 13 eV it has a second gently sloping maximum. The reflection coefficient of the clean (Ill) face of tungsten has three maxima at energies of 2.5, 6.5 and 13 eV. At low electron energies the plots of dependence of the coefficient of secondary electron emission on energy are similar to the plots of the reflection coefficient. Z Yak&ova and N A Gorbatyy, 1zv Akad Nauk SSSR Ser Fiz, 35 (3), 1971, 553-559 (in Russian). 33 134. Investigation of positive ion deceleration processes in silicon carbide. (USSR) Penetration depths and the number of excited electron-hole pairs in silicon carbide are determined for hydrogen, dueterium, helium, sodium, and potassium ions with energy of 20 keV using simultaneous observation of ion- and cathodoluminescence. V V Makarov and N N Petrov, Fiz Tekh Polup, 5 (3). 197 I, 5 l@-5 I3 (in Russian). 33 135. Structure of lanthanum films on (110) and (100) faces of tungsten.
(USSR) Lanthanum films evaporated on (110) and (100) tungsten faces are investigated with the aid of low energy electron diffraction techniques in a sealed ultrahigh vacuum glass device. It is found that for increasing lanthanum concentration on the tungsten surface, a series of ordered structures of adsorbed atoms is formed. Variation of the work function is also determined during lanthanum condensation and structural changes. Experimental results are discussed. DA Gorodet;kty et al, Izv Akad Nauk SSSR Ser Fiz, 35 (3). 1971,585590 (in Russian). 33 136. Influence of radiation-less transitions on luminescence spectrum of excited particles ejected from solid targets by fast argon ions.
(USSR) Influence of the process of resonance ionization on the luminescence spectrum of excited particles ejected from solid targets-metal (copper), semiconductor (silicon) and dielectric (alumina)-by 20 keV argon ions with energy is investigated. The experimental apparatus consists of an ion arc source, a magnetic analyzer and a target chamber. The residual gas pressure was 1 i: lO-6 torr in the target chamber during experiments. V V Gritsyna et al, Izv Akad Nauk SSSR Ser Fiz, 35 (3). 1971,57X-584 (in Russian). 137. Peculiarities of elastic reflection and inelastic electrons in lithium oxide films. (USSR)
scattering
33 of slow
Secondary electron emission of oxide films on the surface of activated alloys containing lithium is investigated in the region of primary electron energies of 0 to 20 eV. L F Afonina et al, Izl’ Akad Nauk SSSR Ser Fiz, 35 (5), 1971, 1049105 I (in Russian). 33 138. Electron
(Czechoslovakia)
beam
equipment
for
micromachining
techniques.
abstracts
127-138
readily disintegrate, and the metallic components may be recovered by conventional techniques. 2 I Braun et al, USSR Patent No 281662, trppl3rd Jan 1969, publd 23rd Dee 1970. 33.
GENERAL PHYSICS AND ELECTRONICS
33 127. Method of stretching disc grids. (USSR) A method of stretching disc grids so as to ensure a uniform disposition of the grid material without distorting the underlying discs is described. The method is based on the creation of a special clamping system which allows the grid to undergo deformation in a radial direction only. To this end the clamps are made in the form of a set of contiguous sectors movable with respect to one another and symmetrically disposed relative to the axis of the grid. The degree of uniformity increases with increasing number of sectors employed. Experience suggests sixteen sectors as a number convenient for most practical purposes. Yu I Abramskii and V A Nikitinskii, USSR Patent No 272440, appl 1st Aug 1966, publd 11th Sept 1970. 128. Ion cyclotron resonance power absorption: for CO,+, N,+ and H,+ ions in their parent gases.
Collision (USA)
33 frequencies
Calculations for ion cyclotron resonance (ICR) gives excellent agreement for instantaneous power absorption with experiment at all pressures. The absorption at resonance initially increases linearly with time and at high pressures levels off at a constant value at saturation. An expression is derived for the average kinetic energy of an ion at saturation in the steady-state limit. Pulsed ICR techniques are used to obtain the instantaneous power absorption curves for N,+, CO,+ and HZ+ ions in their parent gases as a function of pressure. From these data, the momentum transfer rate constants and their dependence on ion kinetic energy are calculated. Values are given at 293’ K. The values are considered in terms of polarization theory. WTHuntress,JChemPhys,55(5), 1stSept 1971,2146-2155. 129. Method for estimating excess kinetic energy of ionization in a pulsed ion source. (USA)
33 products
A pulsed ion source in a 60 magnetic sector mass spectrometer was used to study the decay of thermal ions and compared with calculations. An increase in ion decay observed for several positive and negative ions is attributed to kinetic energy in excess of their ambient thermal energy. Consideration is given to experimental conditions and particle condition effects. I Platzner et al, J Chem Phys, 55 (5), 1st Sept 197 I, 2276-2278. 33
energy-loss spectrum of oxygen. (USA) The apparatus used consisted of an ion source and mass analyzer followed by an energy selector, a collision chamber, a second energy selector and a detector. It was designed to study the energy lost by ions with initial energies of 50 eV-5 keV. The oxygen atom was studied by measuring the kinetic energy lost by 100 eV-4 keV H+, H,+ and He+ which are inelastically scattered. The SchumannRunge continuum appears to be the result of at least two different transitions. The optically forbidden Hertzberg continuum is observed in all of the ion-impact spectra. Triplet-singlet transitions are the most intense features of the H,+ and He+ impact spectra. J H Moore, J Chem Phys, 55 (6), 15th Sept 1971,2760-2764. 33 131. Vapour-phase growth of several III-V compound semiconductors. (USA) A review is presented of a vapour-phase growth method that has been developed for the synthesis of a broad spectrum of 111-V compounds. The predominant feature of this technique is the use of gases as the source chemicals, thereby providing improved control of the chemical composition, homogeneity, crystalline perfection, and impurity concentrations and distributions of the epitaxial layers. As a result, a number of notable advances have been made with respect to the material properties and device utilization of several 111-V compounds. The chemistry of the deposition processes was studied by means of a mass spectrometer coupled to the vapour-phase growth system. Results of these studies are presented and discussed. J J Tietjen et al, J Vat Sri Tech&, 8 (5), Sept/Oct 1971, S5-SI I. 33 132. Applications of ion implantation for new device concepts. (USA) Ion-implantation doping offers many potential advantages over con130. Ion-impact
38
ventional techniques such as ditfusion and epitaxial growth for the fabrication of new devices. The general features of ion implantation are reviewed. Examples from silicon-device fabrication are chosen to illustrate the manner in which ion-implantation doping complements diffusion and epitaxial growth to provide device architects with increased flexibility in device design. B L Crowder, J Vat Sci Technol, 8 (5), Sept/Ort 191I, S7 I -S75. 33 133. Reflection of slow electrons from (110) and (111) faces of tungsten
single crystal. (USSR) Energy dependence of the coefficient of elastic reflection of secondary electron emission and the coefficient of true secondary inelastically reflected electrons for the clean and contaminated (110) and (111) faces of tungsten single crystal is investigated in the energy range of primary electrons of 1 to 30 eV at normal beam incidence. The experiments have been performed in sealed glass devices. A Myers electron gun with indirectly heated lanthanum hexaboride cathode was used as a source of a monoenergetic slow electron beam. For analysis of the energy distribution of secondary electrons a spherical capacitor was employed. Barium and titanium getters reduced the pressure in the sealed devices to 1% 10 !’torr. It is found that the coefficient of reflection of the clean (110) face is 0.08 at energy of 1 eV, it reaches a maximum of 0.34 at energy of 3.3 eV and decreases at higher energies. Around 13 eV it has a second gently sloping maximum. The reflection coefficient of the clean (Ill) face of tungsten has three maxima at energies of 2.5, 6.5 and 13 eV. At low electron energies the plots of dependence of the coefficient of secondary electron emission on energy are similar to the plots of the reflection coefficient. Z Yak&ova and N A Gorbatyy, 1zv Akad Nauk SSSR Ser Fiz, 35 (3), 1971, 553-559 (in Russian). 33 134. Investigation of positive ion deceleration processes in silicon carbide. (USSR) Penetration depths and the number of excited electron-hole pairs in silicon carbide are determined for hydrogen, dueterium, helium, sodium, and potassium ions with energy of 20 keV using simultaneous observation of ion- and cathodoluminescence. V V Makarov and N N Petrov, Fiz Tekh Polup, 5 (3). 197 I, 5 l@-5 I3 (in Russian). 33 135. Structure of lanthanum films on (110) and (100) faces of tungsten.
(USSR) Lanthanum films evaporated on (110) and (100) tungsten faces are investigated with the aid of low energy electron diffraction techniques in a sealed ultrahigh vacuum glass device. It is found that for increasing lanthanum concentration on the tungsten surface, a series of ordered structures of adsorbed atoms is formed. Variation of the work function is also determined during lanthanum condensation and structural changes. Experimental results are discussed. DA Gorodet;kty et al, Izv Akad Nauk SSSR Ser Fiz, 35 (3). 1971,585590 (in Russian). 33 136. Influence of radiation-less transitions on luminescence spectrum of excited particles ejected from solid targets by fast argon ions.
(USSR) Influence of the process of resonance ionization on the luminescence spectrum of excited particles ejected from solid targets-metal (copper), semiconductor (silicon) and dielectric (alumina)-by 20 keV argon ions with energy is investigated. The experimental apparatus consists of an ion arc source, a magnetic analyzer and a target chamber. The residual gas pressure was 1 i: lO-6 torr in the target chamber during experiments. V V Gritsyna et al, Izv Akad Nauk SSSR Ser Fiz, 35 (3). 1971,57X-584 (in Russian). 137. Peculiarities of elastic reflection and inelastic electrons in lithium oxide films. (USSR)
scattering
33 of slow
Secondary electron emission of oxide films on the surface of activated alloys containing lithium is investigated in the region of primary electron energies of 0 to 20 eV. L F Afonina et al, Izl’ Akad Nauk SSSR Ser Fiz, 35 (5), 1971, 1049105 I (in Russian). 33 138. Electron
(Czechoslovakia)
beam
equipment
for
micromachining
techniques.