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Vacuum properties of materials for electronic devices
Book reviews
Materials for Electronics. (Metals and alloys). 2nd Revised Edition. By M A Lebedinsky, Energiya, Moscow-Leningrad (1966), 232 pages (in Russian--original title: Electrovakuumnye material)'. Metally i
splavy). This book might be more aptly titled: "Metallurgy for Electronic Vacuum Device Designers". It is aimed at designers of all types of tubes, vacuum and gas-filled rectifiers and photosensitive devices. After a brief review of electronic devices and the conventional design of their electrodes, the fundamentals of crystallography and methods of investigation for electrical, mechanical and chemical properties are given. The metallurgy of the common metals is described and some modern methods such as high vacuum induction melting, float zone melting and electron beam melting are presented with practical examples. Then the individual metals are dealt with: W, Mo, Ta, Nb, Ti, Zr, Re and their alloys; Ni, Fe, Cu, A1 and their alloys: alkaline earth metals; Mg, Hg, Ag, Au, Pt and solders; and ferromagnetic alloys. For each individual metal, typical methods of preparation are presented and then the properties are described. Few theoretical equations appear but a large amount of data is presented in tables which, for clarity, are all reproduced in the same style. Soviet standards for each metal or alloy are also presented since the book covers only Soviet production; no comparisons are made with foreign methods or material properties. Although the book has no great shortcomings, in so far as the explanations given are clear and much data is lucidly presented it may not be of great interest to Western engineers; its main value will be to metallurgists wishing to compare conventional materials from the USSR with those of Western countries. 15 references are given, all in Russian although some are translations (eg, W Espe's book).
Vacuum Properties of Materials for Electronic Devices. By N V Cherepnin, Sovetskoe radio, Moscow, 1966, 350 pages (in Russian-original title: Vakuumnye svoystva materialov dlya elektronnykh
priborov). Although similar in title to Lebedinsky's book, this work makes a different approach to the problems of materials for electronic vacuum devices. More than anything else, this is a book about the interaction of gases and solids. The first chapter deals with the undesirable transfer of materials to a cathode, arising from evaporation or other mechanisms. In the second chapter the physical principles of interactions between atomic and molecular gases and solids are considered. Physical adsorption and desorption are analyzed in great detail and compared to chemisorption. Other topics covered include: migration of adsorbed gas; dissolved gases and diffusion in metals; metal oxidation; and the constitution of gas bubbles inside metals. The third chapter is a detailed account of the degassing of metals together with some practical data. The vacuum properties of glass and mica are given in the fourth and fifth chapters and the sorption and degassing of ceramics are briefly discussed. The following chapter (the largest one) contains a very detailed account of gas permeation through materials used in electronic device bulbs. This information is of great importance to all vacuum engineers since the same group of materials provide the basis for all vacuum devices. Gas flow through pores and the constitution of these pores in materials are also discussed. Coverage extends even to consideration of the inaccuracies associated with evaluation of gas permeation from measurements. Methods of leak detection are given only brief mention since Lanis and Levina's book, which has been published in the USSR, affords a very detailed treatment of this subject. However, typical sensitivities, as given in the book under
review, are too high. For example, the sensitivity of the Soviet type PTI-6 leak detector is given as 5 x 10T M torr-litre/sec while the actual sensitivity is only 3 x 10-8 torr-litre/sec. These errors may arise from use of an unusual unit (cm 3 torr/sec) and taking typical values, uncorrected, from sources where the other unit is used. The last chapter deals with getters and residual gas gettering, but only getter types used in electronic tubes are considered so this chapter will only benefit electron tube designers. A prominent feature of the book is the thorough compilation of Western and Soviet literature, giving the reader a well-prepared clear and critical review of results of investigations from all over the world. The only serious shortcoming is that units employed in equations are often not indicated. This means that while the general picture is accurate, the reader must consult other texts to perform practical calculations. However, it must be conceded that where this occurs, the correct publication is always referenced. 285 references are given, 115 in Russian although many of these are translations from English.
Mass-Spectrometer Methods. By N N Shttmulovskiy and R I Stakhovskiy, Energiya, M oscow-Leningrad (1966) 160 pages (in Russian-original title: Mass-spektral' nve metody). Mass-spectrometry has many applications, including the chemical analysis of materials and therefore it may be used for testing and control in chemical plants. This small book has been published to inform chemical engineers of this modern method. As this book is aimed at non-specialists in vacuum technology and mass-spectrometry techniques, presentation of basic knowledge is a first essential. In the first chapter the principles of magnetic-type and dynamic mass-spectrometers are explained. The much used quadrupole analyzer, though it is well known in USSR, is not mentioned. On the other hand, the topatron, which is not produced in USSR, is described in 3 pages. Without any explanation of argon sensitivity, values are given for some equipment, using the wrong unit, mm Hg (correct unit is torr-'), and with printing errors. The general principles of measured mass-spectra processing are given in the second chapter. Gaugehead vacuum systems and gas inlet systems are described in the third chapter. Naturally, only the basic design principles of high vacuum systems are presented. Tabulated data on some Soviet pumps (mechanical, oil diffusion and mercury pumps) are added. Calculation of the gas flow through a capillary is explained in more detail. It should be mentioned that the given formulae are correct only for a very long tube, though usually this condition is fulfilled. Needle and control valves are not mentioned. The influence of the ion source of a magnetic-type mass-spectrometer on the measuring errors is described in detail in the fourth chapter since this is a very important problem for users of this instrument. Measuring and recording systems are described in the fifth chapter. Basic principles of electrical circuitry are provided but unfortunately the importance of the time constant of a preamplifier is not mentionedThe following chapter gives information on some Soviet commer. cially-available mass spectrometers compared to CEC's type 21-130 model. In the last chapter automatic periodic mass-spectrometer gas analyzer calibration methods are discussed. This book has two basic shortcomings: first, the given information is often obsolete. For example: as a modern aigital computer for mass-spectra processing, the 15-year old-punch card calculator is presented, though experiments have been performed with mass spectra identification by electronic digital computer. The "typical" characteristics of electrometer circuits for ion current measuring are typical values for preamplifiers of 20 years ago. Among 111 refer227
Materials for Electronics. (Metals and alloys). 2nd Revised Edition. By M A Lebedinsky, Energiya, Moscow-Leningrad (1966), 232 pages (in Russian--original title: Electrovakuumnye material)'. Metally i
splavy). This book might be more aptly titled: "Metallurgy for Electronic Vacuum Device Designers". It is aimed at designers of all types of tubes, vacuum and gas-filled rectifiers and photosensitive devices. After a brief review of electronic devices and the conventional design of their electrodes, the fundamentals of crystallography and methods of investigation for electrical, mechanical and chemical properties are given. The metallurgy of the common metals is described and some modern methods such as high vacuum induction melting, float zone melting and electron beam melting are presented with practical examples. Then the individual metals are dealt with: W, Mo, Ta, Nb, Ti, Zr, Re and their alloys; Ni, Fe, Cu, A1 and their alloys: alkaline earth metals; Mg, Hg, Ag, Au, Pt and solders; and ferromagnetic alloys. For each individual metal, typical methods of preparation are presented and then the properties are described. Few theoretical equations appear but a large amount of data is presented in tables which, for clarity, are all reproduced in the same style. Soviet standards for each metal or alloy are also presented since the book covers only Soviet production; no comparisons are made with foreign methods or material properties. Although the book has no great shortcomings, in so far as the explanations given are clear and much data is lucidly presented it may not be of great interest to Western engineers; its main value will be to metallurgists wishing to compare conventional materials from the USSR with those of Western countries. 15 references are given, all in Russian although some are translations (eg, W Espe's book).
Vacuum Properties of Materials for Electronic Devices. By N V Cherepnin, Sovetskoe radio, Moscow, 1966, 350 pages (in Russian-original title: Vakuumnye svoystva materialov dlya elektronnykh
priborov). Although similar in title to Lebedinsky's book, this work makes a different approach to the problems of materials for electronic vacuum devices. More than anything else, this is a book about the interaction of gases and solids. The first chapter deals with the undesirable transfer of materials to a cathode, arising from evaporation or other mechanisms. In the second chapter the physical principles of interactions between atomic and molecular gases and solids are considered. Physical adsorption and desorption are analyzed in great detail and compared to chemisorption. Other topics covered include: migration of adsorbed gas; dissolved gases and diffusion in metals; metal oxidation; and the constitution of gas bubbles inside metals. The third chapter is a detailed account of the degassing of metals together with some practical data. The vacuum properties of glass and mica are given in the fourth and fifth chapters and the sorption and degassing of ceramics are briefly discussed. The following chapter (the largest one) contains a very detailed account of gas permeation through materials used in electronic device bulbs. This information is of great importance to all vacuum engineers since the same group of materials provide the basis for all vacuum devices. Gas flow through pores and the constitution of these pores in materials are also discussed. Coverage extends even to consideration of the inaccuracies associated with evaluation of gas permeation from measurements. Methods of leak detection are given only brief mention since Lanis and Levina's book, which has been published in the USSR, affords a very detailed treatment of this subject. However, typical sensitivities, as given in the book under
review, are too high. For example, the sensitivity of the Soviet type PTI-6 leak detector is given as 5 x 10T M torr-litre/sec while the actual sensitivity is only 3 x 10-8 torr-litre/sec. These errors may arise from use of an unusual unit (cm 3 torr/sec) and taking typical values, uncorrected, from sources where the other unit is used. The last chapter deals with getters and residual gas gettering, but only getter types used in electronic tubes are considered so this chapter will only benefit electron tube designers. A prominent feature of the book is the thorough compilation of Western and Soviet literature, giving the reader a well-prepared clear and critical review of results of investigations from all over the world. The only serious shortcoming is that units employed in equations are often not indicated. This means that while the general picture is accurate, the reader must consult other texts to perform practical calculations. However, it must be conceded that where this occurs, the correct publication is always referenced. 285 references are given, 115 in Russian although many of these are translations from English.
Mass-Spectrometer Methods. By N N Shttmulovskiy and R I Stakhovskiy, Energiya, M oscow-Leningrad (1966) 160 pages (in Russian-original title: Mass-spektral' nve metody). Mass-spectrometry has many applications, including the chemical analysis of materials and therefore it may be used for testing and control in chemical plants. This small book has been published to inform chemical engineers of this modern method. As this book is aimed at non-specialists in vacuum technology and mass-spectrometry techniques, presentation of basic knowledge is a first essential. In the first chapter the principles of magnetic-type and dynamic mass-spectrometers are explained. The much used quadrupole analyzer, though it is well known in USSR, is not mentioned. On the other hand, the topatron, which is not produced in USSR, is described in 3 pages. Without any explanation of argon sensitivity, values are given for some equipment, using the wrong unit, mm Hg (correct unit is torr-'), and with printing errors. The general principles of measured mass-spectra processing are given in the second chapter. Gaugehead vacuum systems and gas inlet systems are described in the third chapter. Naturally, only the basic design principles of high vacuum systems are presented. Tabulated data on some Soviet pumps (mechanical, oil diffusion and mercury pumps) are added. Calculation of the gas flow through a capillary is explained in more detail. It should be mentioned that the given formulae are correct only for a very long tube, though usually this condition is fulfilled. Needle and control valves are not mentioned. The influence of the ion source of a magnetic-type mass-spectrometer on the measuring errors is described in detail in the fourth chapter since this is a very important problem for users of this instrument. Measuring and recording systems are described in the fifth chapter. Basic principles of electrical circuitry are provided but unfortunately the importance of the time constant of a preamplifier is not mentionedThe following chapter gives information on some Soviet commer. cially-available mass spectrometers compared to CEC's type 21-130 model. In the last chapter automatic periodic mass-spectrometer gas analyzer calibration methods are discussed. This book has two basic shortcomings: first, the given information is often obsolete. For example: as a modern aigital computer for mass-spectra processing, the 15-year old-punch card calculator is presented, though experiments have been performed with mass spectra identification by electronic digital computer. The "typical" characteristics of electrometer circuits for ion current measuring are typical values for preamplifiers of 20 years ago. Among 111 refer227