Abstract. 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 CdllgTe 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 TEIO mode cannot be used in our case.By applying a magnetic field in extraordinary Voigt configuration. galvanomagnetic measurements have been carried Qut which yield the mobility and thus the carrier concentration. These results are also in good agreement with van der Pauw transport measurements.. 72.80.Ey, 78.70.Gq [here is a growing interest in II-VI semiconductors bepuse of their potential applications as devices in the areas ~f opto-electronics and photonics. Their bandgap spans a !wide range from the infrared (CdHgTe) to the violet (ZnS). (consequently, some members of this semiconcutors family lire used as sensitive infrared detectors while others will be iauitable for the realization of LED's etc. with light emission pn the blue part of the visible spectrum. But a number of F hnical problems have to be overcome before we know . w to fabricate reliable devices of this kind. A major step i towards solving these problems is the growth of high quality epitaxial films by means of a new, recently developed growth process, namely photoassisted molecular beam epitaxy (PAMBE) [1,2]. The growth of such films has always been difficult because of the tendency of U-VI compounds to incorporate local defects such as vacancies, interstilials and impurities [3). After the growth of the epitaxial layers, it is absolutely necessary to characterize the samples, i.e. to measure the conductivity, the Hall effect etc., in order to control and optimize their quality with sufficient accuracy in a short time. The knowledge of the electrical transport parameters is especially required in the field of device fabrication. Unfortunately, that is often hampered by the fact that it is difficult or sometimes even impossible to obtain good ohmic contacts. One reason for this is the well known tendency of self-compensation in II-VI compounds.To avoid these problems. a...
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