Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen
OPUS4-3441 Wissenschaftlicher Artikel Greiner, P.; Polignone, L.; Becker, Charles R.; Geick, R. Contactless measurement of the conductivity of II-VI epitaxial layers by means of the partially filled waveguide method We report the contactless determination of the conductivity, the mobility and the carrier concentration of II-VI semiconductors by means of the technique of the partially filled waveguide at a microwave frequency of 9 GHz. The samples are CdHgTe epitaxial layers, grown on CdZnTe substrates by molecular beam epitaxy. The conductivity is determined from the transmission coefficient of the sample in the partially filled waveguide. For the analysis of the experimental data, the complex transmission coefficient is calculated by a rigorous multi-mode matching procedure. By varying the conductivity of the sample, we obtain an optimum fit of the calculated data to the experimental results. Comparison with conductivity data determined by the van der Pauw method shows that our method allows to measure the conductivity with good accuracy. The behaviour of the transmission coefficient of the sample is discussed in dependence on the layer conductivity, the layer thickness and the dielectric constant of the substrate. The calculations require to consider in detail the distribution of the electromagnetic fields in the sample region. The usual assumption of a hardly disturbed TE\(_{10}\) mode cannot be used in our case. By applying a magnetic field in extraordinary Voigt configuration. galvanomagnetic measurements have been carried out which yield the mobility and thus the carrier concentration. These results are also in good agreement with van der Pauw transport measurements. 1992 urn:nbn:de:bvb:20-opus-37838 Physikalisches Institut
OPUS4-3143 Wissenschaftlicher Artikel Geis, G.; Geick, R.; Becker, Charles R.; Wagner, V. Antiferromagnetic resonance in CoO/NiO mixed crystals We have studied the lowest magnetic excitation of Ni\(_{1-x}\)Co\(_x\)O mixed crystals for 0.94 \(\leq\) x \(\leq\) 1. Together with previous results for 0.02 \(\leq\) x \(\leq\) 0.07 and neutron data for x = 0.14 and x = 0.30, the results are discussed by means of a model, especially the variation of AFMR frequency and preferred spin direction with Co concentration x. 1977 urn:nbn:de:bvb:20-opus-31239 Physikalisches Institut
OPUS4-2674 Wissenschaftlicher Artikel Becker, Charles R.; Lau, Ph.; GEICK, R.; Wagner, V. Antiferromagnetic Resonance in NiO:Co\(^{2+}\) and NiO:Fe\(^{2+}\) No abstract available. 1975 urn:nbn:de:bvb:20-opus-30772 Physikalisches Institut
OPUS4-3177 Wissenschaftlicher Artikel Shanjia, Xu; Xinzhang, Wu; Boege, P.; Schäfer, H.; Becker, Charles R.; Geick, R. Scattering characteristics of 3-D discontinuity consisting of semiconductor sample filled in waveguide with gaps No abstract available 1993 urn:nbn:de:bvb:20-opus-37964 Physikalisches Institut
OPUS4-3178 Wissenschaftlicher Artikel Shanjia, Xu; Xinzhang, Wu; Greiner, P.; Becker, Charles R.; Geick, R. Microwave transmission and reflection of stratified lossy dielectric segments partially filled waveguide The microwave transmission and reßection is evaluated for stratified lossy dielectric segments partially filling the rectangular waveguide by the method which combines the multimode network theory with the rigorous mode matching procedure. As an example, we investigate in detail the microwave scattering properties of II-VI-epitaxial layer on a lossy dielectric substrate inserted in the rectangular waveguide. The experimental data verify the accuracy and the effectiveness of the present method. Extensive numerical results are presented to establish useful guidelines for the contactless microwave measurement of the conductivity of the epitaxiallayer. 1992 urn:nbn:de:bvb:20-opus-37958 Physikalisches Institut
OPUS4-3187 Konferenzveröffentlichung Boege, P.; Schäfer, H.; Shanjia, Xu; Xinzhang, Wu; Einfeldt, S.; Becker, Charles R.; Hommel, D.; Geick, R. Improved conductivity-measurement of semiconductor epitaxial layers by means of the contactless microwave method Measurements and calculations of the scattering-characteristics of stratified lossy dielectric blocks completely filling a waveguide cross section are presented. The method is used for contactless conductivity measurements of MBE-grown II-VI semiconductor layers. 1994 urn:nbn:de:bvb:20-opus-37763 Physikalisches Institut
OPUS4-7154 Wissenschaftlicher Artikel Xu, Shanjia; Sheng, Xinqing; Greiner, P.; Becker, Charles R.; Geick, R. High-order finite-element analysis of scattering properties of II-VI semiconductor materials The sattering characteristics ot the n-VI semiconductors were analyzed by a method which combines the second-order finite-element method with the rigorous mode matching procedure. The method avolds the difficulty of solving the complex transcendental equation introduced in the multimode network method and calculates all the eigenvalues and eigenfunctions simultaneously which are needed for the mode matching treatment in the longitudinal direction. As a result, the whole solution procedure is significantly simplified. A comparison is given between the experimental data and the calculated results obtained with this analysis and tbe network method. Very good agreement has been achieved, the accuracy and efficiency of the present method are thus verified. 1994 urn:nbn:de:bvb:20-opus-86283 Physikalisches Institut