Showing papers in "Active and Passive Electronic Components in 1975"

Field Assisted Glass Sealing

Abstract: The paper reviews the experimental, theoretical and applications work by several authors on a glass sealing technique which was announced five years ago. In the process, an electrostatic field is utilized to promote bonding at relatively low temperatures. The process variables and seal properties are described in detail. A discussion is presented of the mechanisms which are believed to play a role in bond formation. As an example of the utility of the technique, its highly successful application to the mounting of strain gauges is described.

A Review of Solder Glasses

Abstract: A compilation of data on solder glasses from the literature is presented. Sources are: Chemical Abstracts, Ceramic Abstracts, Abstracts in Physics and Chemistry of Glasses, and pertinent books. Even though not exhaustive, domestic and foreign sources are included.

Heat dissipation and ripple current rating in electrolytic capacitors

Abstract: The ripple current rating in electrolytic capacitors is limited by the maximum allowable temperature rise inside the capacitor. The temperature rise is determined by the I2 R losses inside the capacitor and the efficiency of heat flow from the interior to the surrounding. The ripple current rating can be extended by either reducing the tan δ of the capacitor or by increasing the efficiency of heat flow to ambient.

The Tunnel Etching of Aluminium

Abstract: The electrochemical potential for the active dissolution of aluminium in sodium chloride solution is found to be linearly related to the logarithm of the chloride ion concentration. The value of E0 calculated on the basis of the postulated electrode reaction is approximately 0.3 V more negative than the experimental value and a similar inequality is observed for bromide and iodide electrolytes.

Production of Resistors by Arc Plasma Spraying

Abstract: Arc plasma spraying (APS) is an accepted method of producing coatings for many engineering applications The wide range of materials that can be used to form the thick film coatings make this technique interesting as an alternative method of producing electrical components and circuits

Electrical Behaviour of Langmuir Films: A Review, Part II

Abstract: The electrical behaviour of thin films obtained by a variety of processes, e.g. thermal evaporation in vacuum, has been extensively studied. The study of organic mono- and multilayer films obtained by the Blodgett–Langmuir technique (commonly referred to as Langmuir films), however, has gained considerable momentum only during the past decades. Unlike evaporated films, the stiking features of these organic films are their controllable thicknesses down to one monolayer (~25 Å) and the possibility of obtaining them free from holes and conducting imperfections. The aim of this paper is to describe the film deposition techniques, some of the properties of the films so obtained and to review their electrical behaviour. It is also intended to make this review a comprehensive and up-to-date source of information for those who are either already engaged in this field or are planning to adopt Langmuir films for future investigations.In this survey, emphasis is put on the possible problems worth further study to get more insight into the basic properties of these films. Further, since the latter possess some interesting electrical properties, this paper may prove useful in the assessment of our depth of knowledge about them and in reducing the existing gap between basic research and technological applications. Their potential usefulness in developing devices is therefore also discussed.The survey has been divided into two parts. Part I was concerned with deposition techniques, the physical properties of Langmuir films and certain electrical properties, namely dielectric behaviour and electrical conduction phenomena. This second part is concerned with electrical breakdown behaviour, voltage induced changes in electrical behaviour (forming) and ionic transport phenomena in the films and finishes, with suggestions as to future trends in work with such films together with a summary of possible applications.To assist the reader, the two parts have been numbered consecutively with regard to sections of the text, figures and references. “Appropriate” references already cited in Part I are given again at the end of this part.

The equivalent series resistance in electrolytic capacitors

Abstract: The analysis of electrolytic capacitors as a distributed network is examined. The parameters contributing to the equivalent series resistance (E.S.R.) have been determined for various production capacitors at low and high frequencies.

On the damage to metallized film capacitors caused by electrical discharges

Abstract: High voltage operation of metallized film capacitors leads to electrical spark breakdown in pockets of gas trapped within the sealed capacitor unit. A simple picture of gas discharge processes in the capacitor is used to identify the role played by electric discharges in the deterioration and ultimate failure of capacitors under accelerated life test.

Expression de la tension photovoltaique induite par transition interbande dans des couches minces de sulfure de zinc

Abstract: En considérant les variations dimensionnelles de la tension photovoltaïque induite en circuit ouvert par des rayonnements lumineux d'énergie supérieure à 3,66 eV dans des structures sandwich Al/ZnS/Au, ainsi que les variations avec le flux lumineux du courant de court-circuit et de la conductance correspondant à la phototransition entre bandes, l'hypothèse d'une quasi-bande de conduction créée par l'ionisation de centres coulombiens est avancée. Elle conduit à une formulation de la tension photovoltaïque en bonne cohérence avec l'expérience.

Etude de la Conduction Ionique du βPbF2

Abstract: Measurements were made with sintered samples in vacuum at 10−5 torr. Voltages of frequencies varying between 0.1 and 5 × 104 Hz at different temperatures (300 to 500 K) were used. The impedance diagrams show two regions.

Variations of Thin Metallic Zinc Film Resistances With Sputtering Rate

Abstract: Variations of resistance of evaporated or sputtered films during deposition have been studied for deposition times lower than five minutes and for resistances higher than 100 [2 sq -1 As our main objective is to study the conduction mechanisms in sputtered films over the thickness range from 200 to 1500 A, (i.e. in the 10 to 100 2 sq -1 sheet resistance range), we report in this note our investigations about the electrical resistance R(T) of zinc films for deposition time, T greater than two minutes and for four average deposition rates. Preparation of films has been described in a previous paper; they are deposited by d.c. diode sputtering of a zinc target (99.9% purity) in an atmosphere of U grade argon. As broken sputtering is equivalent to continuous deposition4, sputtering was stopped every minute to measure the resistance R with a multimeter. The average sputtering rate was determined from the deposition time and the film thickness measured by an optical method; this method is adequate for we have observed very slight anisotropic effects, 6 which seem more important for higher sputtering rates; it varied with the intensity Ie of the glow discharge current, the voltage Ue remaining constant (curves 1, 2, 3 on Figure 2). Variations of the deposition rate as a function of the intensity Ie of glow discharge current for a voltage equal to 1500 V are shown in Figure 1. This curve is in good agreement with the results of Laville Saint-Martin who established that sputtering rate v is given by

New alumina substrates for microelectronics

Abstract: Alumina substrates of Al2O3–MgO–Cr2O3 give excellent surface smoothness. These were studied with respect to their green tapes, the surface finish of fired substrates, and in particular smoothness. The factors contributing to these characteristics were investigated, in particular the effect of the addition of Cr2O3 on surface smoothness.