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Photoelectric analysis of vacuum deposited films
Abstracts of papers
ceramics are the only major constructional materials; bearings are lubricated by Microseal impregnation.
Photoelectric analysis of vacuum deposited films
gauges. In addition, a sweeping oscillator and the detector's selective amplifier are necessary. The amplified output is a 0-10 volts signal (ac and/or dc), proportional to the molecular beam intensity and readily applicable to source monitoring. Furthermore, a current integrator gives the total thickness of the deposit in the case of condensable vapours.
Evgen Kansky, lnstitut za elektroniko in vakuumsko tehniko, Ljubljana, Teslova 30, Yugoslavia The photoelectric emission current of a solid at constant illumination depends on its structure and chemical composition. Therefore phase changes in a two or more component system can be detected by measurements of the photoelectric emissivity. Discontinuities in the diagram of photoelectric emissivity vs system composition indicate phase changes. The method is proposed to be called photoelectric analysis. Its application to the Cs-Sb system, realised by vacuum evaporation, is described. In experiments discussed, the system composition was determined by electrochemical measurements of alkali metal activity.
The sweeping electron beam ionization gauge as evaporation rate monitor
Problems associated with quartz crystal monitors and their solution
Richard P Riegert, Member, Technical Staff; Sloan Instruments Corporation, Santa Barbara, California, USA The accuracy of quartz crystal monitors in controlling thickness and rate of deposition of thin films will probably never be exceeded where good technique is involved. The abuse of Quartz crystal monitors is extensive and with due consideration of their shortcomings, one can prepare to achieve the ultimate in performance. Error-inducing conditions such as excessive temperature, stress, overloading, thermal shock, crystal defects, improper cut direction, and low-drive signals can all be accommodated and virtually eliminated. Detailed descriptions of the symptoms, the problems, and solutions are to be discussed.
B Zega, Battelle Institute, Geneva Research Center, Geneva, Switzerland A novel method of detecting and monitoring molecular beams in vacuum, based on the ionization principle, has been developed, giving an alternating output signal proportional to the beam intensity and independent of the background pressure. The device contains no mechanical chopper. An electron beam of well defined dimensions and intensity is deflected between plates or coils in order to sweep the space traversed by the molecular beam. At each crossing of the two beams, an ion pulse is produced, which is superimposed on the continuous ionization of the residual gas. One possible execution of such a gauge is described, intended specially to monitoring of thin film depositions. It contains a low energy electron gun, a pair of deflection coils, an electronand an ion-collector. Some experiments on the calibration of the device for different metals and composite vapours are given. A good independence of the background pressure is obtained, allowing monitoring at rates as low as a few/~/sec in vacuum better than 10 -4 torr. Higher rates (over 100 A/sec to more than 1000 ,~/sec) can be monitored even at higher pressures. The device presents many advantages over other systems: (a) It operates continuously, is thus especially suitable for long runs and thick deposits. Its very little maintenance enables it to be used for industrial applications. (b) It contains no moving part in vacuum. The output signal is alternating (about 1 kHz) and can be easily amplified. (c) It is insensitive to temperature changes during runs, and can withstand temperatures of up to 150°C. An execution bakable at 400'C is envisaged. Under normal conditions, no cooling is necessary. (d) It is insensitive to ions, electrons and ionizing radiations of external origin, such as electron beam heated sources. (e) It can be effectively shielded against electric and magnetic fields owing to its compact geometry. An electrical supply unit, accompanying the gauge, contains a feedback-regulated emission current circuit and the acceleration voltage supply, similar to the conventional ionization
Crystalline semiconductors vacuum deposited on amorphous substrates
Mrs Barbara Neumann, Chicago, Illinois, USA A combination of the two previously described methods of vacuum deposition is investigated to obtain a process yielding thin crystalline films of high structural quality and precise composition, independent of epitaxial substrate. One method is that of scanning the substrate with a beam of finite cross-sectional area, and the other method is the production of an intermittent, pulsed vapour or ion beam. Details of the procedure and results are presented.
Some experiments of the evaporation synthesis. Formation of TiN and ZrN
Akio Itoh, Electrotechnical Laboratory, Tanashi, Tokyo, Japan A new manufacturing technique for thin film materials, evaporation synthesis, has been developed. The transition metals are very active especially at the initial stage of deposition. By ejecting the nitrogen molecular beam simultaneously with the evaporated metal molecular fluxes on the same position of the substrate, the active metal atoms reacted with the gas molecules in the process of deposition and the formation of TiN and ZrN was carried out. Ti and Zr were deposited by means of electron bombardment or an electron beam evaporation source, while nitrogen gas was introduced through a tantalum tube. By changing the ratio of gas throughput to the deposition rate of Ti and Zr, various compositions of compounds, TiNx, ZrN x (0 < x ~< 1.0) were obtained. The influences of substrate temperature and N~ beam temperature on degree of nitridation were investigated. Furthermore, the variation of the resistivity depending on the film compositions were determined. 149
ceramics are the only major constructional materials; bearings are lubricated by Microseal impregnation.
Photoelectric analysis of vacuum deposited films
gauges. In addition, a sweeping oscillator and the detector's selective amplifier are necessary. The amplified output is a 0-10 volts signal (ac and/or dc), proportional to the molecular beam intensity and readily applicable to source monitoring. Furthermore, a current integrator gives the total thickness of the deposit in the case of condensable vapours.
Evgen Kansky, lnstitut za elektroniko in vakuumsko tehniko, Ljubljana, Teslova 30, Yugoslavia The photoelectric emission current of a solid at constant illumination depends on its structure and chemical composition. Therefore phase changes in a two or more component system can be detected by measurements of the photoelectric emissivity. Discontinuities in the diagram of photoelectric emissivity vs system composition indicate phase changes. The method is proposed to be called photoelectric analysis. Its application to the Cs-Sb system, realised by vacuum evaporation, is described. In experiments discussed, the system composition was determined by electrochemical measurements of alkali metal activity.
The sweeping electron beam ionization gauge as evaporation rate monitor
Problems associated with quartz crystal monitors and their solution
Richard P Riegert, Member, Technical Staff; Sloan Instruments Corporation, Santa Barbara, California, USA The accuracy of quartz crystal monitors in controlling thickness and rate of deposition of thin films will probably never be exceeded where good technique is involved. The abuse of Quartz crystal monitors is extensive and with due consideration of their shortcomings, one can prepare to achieve the ultimate in performance. Error-inducing conditions such as excessive temperature, stress, overloading, thermal shock, crystal defects, improper cut direction, and low-drive signals can all be accommodated and virtually eliminated. Detailed descriptions of the symptoms, the problems, and solutions are to be discussed.
B Zega, Battelle Institute, Geneva Research Center, Geneva, Switzerland A novel method of detecting and monitoring molecular beams in vacuum, based on the ionization principle, has been developed, giving an alternating output signal proportional to the beam intensity and independent of the background pressure. The device contains no mechanical chopper. An electron beam of well defined dimensions and intensity is deflected between plates or coils in order to sweep the space traversed by the molecular beam. At each crossing of the two beams, an ion pulse is produced, which is superimposed on the continuous ionization of the residual gas. One possible execution of such a gauge is described, intended specially to monitoring of thin film depositions. It contains a low energy electron gun, a pair of deflection coils, an electronand an ion-collector. Some experiments on the calibration of the device for different metals and composite vapours are given. A good independence of the background pressure is obtained, allowing monitoring at rates as low as a few/~/sec in vacuum better than 10 -4 torr. Higher rates (over 100 A/sec to more than 1000 ,~/sec) can be monitored even at higher pressures. The device presents many advantages over other systems: (a) It operates continuously, is thus especially suitable for long runs and thick deposits. Its very little maintenance enables it to be used for industrial applications. (b) It contains no moving part in vacuum. The output signal is alternating (about 1 kHz) and can be easily amplified. (c) It is insensitive to temperature changes during runs, and can withstand temperatures of up to 150°C. An execution bakable at 400'C is envisaged. Under normal conditions, no cooling is necessary. (d) It is insensitive to ions, electrons and ionizing radiations of external origin, such as electron beam heated sources. (e) It can be effectively shielded against electric and magnetic fields owing to its compact geometry. An electrical supply unit, accompanying the gauge, contains a feedback-regulated emission current circuit and the acceleration voltage supply, similar to the conventional ionization
Crystalline semiconductors vacuum deposited on amorphous substrates
Mrs Barbara Neumann, Chicago, Illinois, USA A combination of the two previously described methods of vacuum deposition is investigated to obtain a process yielding thin crystalline films of high structural quality and precise composition, independent of epitaxial substrate. One method is that of scanning the substrate with a beam of finite cross-sectional area, and the other method is the production of an intermittent, pulsed vapour or ion beam. Details of the procedure and results are presented.
Some experiments of the evaporation synthesis. Formation of TiN and ZrN
Akio Itoh, Electrotechnical Laboratory, Tanashi, Tokyo, Japan A new manufacturing technique for thin film materials, evaporation synthesis, has been developed. The transition metals are very active especially at the initial stage of deposition. By ejecting the nitrogen molecular beam simultaneously with the evaporated metal molecular fluxes on the same position of the substrate, the active metal atoms reacted with the gas molecules in the process of deposition and the formation of TiN and ZrN was carried out. Ti and Zr were deposited by means of electron bombardment or an electron beam evaporation source, while nitrogen gas was introduced through a tantalum tube. By changing the ratio of gas throughput to the deposition rate of Ti and Zr, various compositions of compounds, TiNx, ZrN x (0 < x ~< 1.0) were obtained. The influences of substrate temperature and N~ beam temperature on degree of nitridation were investigated. Furthermore, the variation of the resistivity depending on the film compositions were determined. 149