Scheinwiderstand und Sperrkennlinien von Silizium-p-n-Übergängen mit Oberflächeninversionsschicht

The equivalent circuit diagram of a p-n junction with a surface inversion layer consists of a chain of finite length with infinitesimal RC circuits. From apparent resistance measurements, the thickness of the space charge region and the channel conductivity were determined, and from these, the total surface charge and the surface potential.In the case of a rectifier of the p-s_p-n type, the inversion layer covers the entire surface of the soft p-conductive silicon. If a rectifier of this kind has a disturbance under the surface, the breakdown voltage increases with the surface charge, i.e., as the channel becomes more pronounced.     

Über das verhalten von kohlenstoff beim zonenziehen von silicium

The behaviour of carbon in a zone-refining process for high purity semiconductor-grade silicon was investigated using ¹⁴C as a radioisotope tracer. Radioautographic pictures show an enhancement of carbon in the crystal parts which are recrystallized last. From the concentration gradient observed in the direction of pulling, and from the concentration step between the last zone and the preceding one a distribution coefficient for carbon of about 0·1 is deduced. Additional activation of ¹⁴C-doped samples by neutrons gave evidence for the dissociation of SiC-complexes under crystal-pulling conditions. Carbon incorporated in such complexes is therefore also removed by the zone-refining process used.     

Über die Abhängigkeit der Widerstandsschwankungen ρmax/ρmin vom Dotierstoff bei tiegelgezogenen Si-Kristallen

The dependence of the maximum resistivity changes of microscopic donor inhomogenities in Si-crystals on the type of impurity is considered. Using the theory of Burton et al. an experimentally found correlation may be interpreted as the consequence of periodic variations in the rate of crystallisation. For the crystals investigated and an effective growth rate of υ = υ₀±Δυ = (4·5±4·2) × 10⁻³ cm sec⁻¹ the results were in good agreement with calculations and measurements.     

Eine neue methode zur Messung kleiner magnetischer felder mit hilfe von Magnetfeldabhängigen widerständen aus indiumantimonid

Because of the symmetry of the magnetoresistance effect in InSb it is possible to build a measuring probe for weak magnetic fields with a high stability. It is not necessary to use a selected and calibrated magnetoresistance device.With the described circuitry the probe delivers an a.c. voltage proportional to the magnetic induction to be measured. After demodulation the resulting d.c. voltage indicates the direction and the value of the magnetic induction parallel to the probe. The variations of the output voltage with no magnetic field between −20°C and +60°C corresponds to 0·2 mG.     

Neue Messgeräte mit hoher Flexibilität

Firmen&;ProdukteSchneider Electric-Reine Multi 9

Neue Messger?te mit hoher Flexibilit?t     

Ergebnisse der experimentellen Weltraumforschung in Graz mit Hilfe von aktiven Experimenten in der Ionosphäre und Magnetosphäre

An overview of two areas of so-called active experiments in space is given. Electron beam emitters on board sounding rockets in the ionosphere cause manifold and sometimes also unexpected interactions between the electron beam, the plasma environment, and the payload. Ion beam emitters on board research satellites in the Earth’s magnetosphere affect the electric potential of the satellites with respect to the ambient plasma. Only a potential that is kept small by suitable measures permits measurements of the ambient plasma at an accuracy which meets present needs.     

LED-Informationstafeln mit hoher Leuchtstärke

Firmen&;ProdukteModeller-Systeml?sung

Sichere Energieversorgung in der Fertigungsindustrie     

Einsatz von innovativen Arbeitsgeräten

Modern overhead line systems call for high quality and operational safety standards as well as high requirements to be met with regard to the work procedures applied in the maintenance, renewal and construction of such systems. The use of innovative equipment ensures optimum working conditions and performance as well as economic efficiency and flexibility.     

Die Beweglichkeit von Ladungsträgern im Stromkanal von MOS-Transistoren

The temperature dependence of the field effect mobility of MOS-transistors have been studied. The deviation of the measured temperature curves from bulk mobility shows, that an essential part of the decrease of the mobility at the semiconductor surface results from scattering of the charge carriers by ionized impurities, located at the semiconductor-oxide interface. Such scattering centers represented by localized surface states, cause a decrease in mobility with increasing surface state density. Applying Brooks-Herring formula, this effect can be explained as the known impurity scattering process.     

Verteilnetze bestimmen die Versorgungsqualität

Ohne Zusammenfassung Kurzfassung eines Vortrags der 42. Fachtagung der ?sterreichischen Gesellschaft für Energietechnik (OGE) im OVE, die am 21. und 22. Oktober 2004 in Graz stattfindet.     

Polymere für Anwendungen in der integrierten Optik — ein Überblick mit ausgewählten Beispielen

Within this paper the development of special polymers for their use in integrated optics is shown exemplarily for selected optical devices (thermooptical switches and arrayed waveguide gratings). Emphasis is put on long-range data transfer in a wavelength region around 1,550 µm. Fluorinated polyacrylates, polycyanurates and triazine-containing reactive polymers were investigated.     

Vergleichsstudie von Methoden der Flächenpressungsmessung

Measurements of contact stresses between elastic bodies are of great importance not only in mechanical and civil engineering but also in medicine, especially in orthopedic fields. On the one hand there are a lot of methods making use of electrical effects and on the other hand there are imprint methods. The accuracy of measuring results depends mainly on the influences of thickness and stiffness of the inserted measuring sheets between the bodies in contact. In this study effects of the elastic properties of the inserted sheet with respect to the stiffness of the elastic bodies were investigated. For this purpose the following well known load cases were chosen:

1. rigid cylindrical body pressed on an elastic half-space,
2. Hertz-problem of two spherical bodies in contact.

For both cases analytical solutions and FE calculations are compared with experimental results.     

Eine Formel verändert die Welt

The capacity formula for the Additive White Gaussian Noise (AWGN-) channel is taken for an example to demonstrate the extreme importance of Information Theory of C.E. Shannon for the transition from the Industrial Age to the Information Age. Exemplarily, typical ways of finding basic theorems in Information Theory are shown by means of two mathematical concepts. Simple relationships between information and energy as well as fundamental existence/nonexistence bounds for analogous and digital communication schemes are derived from the capacity formula. General comments on the importance of fundamental theories for the progress in technologies and on the rule of humanities in this process conclude the paper.