Über die Co(C)-Begleitphase des synthetischen Diamanten

The concentration dependence of the specific atomic volume on the carbon side of the Co—C system is constructed. By means of this the carbon content of the satellite phase is determined equal to ∼ 3.7 at.% Therefore the satellite is considered as the terminal Co:0,03 C solid solution, and seems to be the product of decomposition of the basic catalyst supersaturated in carbon.     

Über die Richtigkeit und Genauigkeit bei der Messung von Netzebenenabständen

The paper emphasizes the principal difference between the terms deviation and error. The relative deviation as a measure of accuracy can be expressed by the total differential, while the relative error as a measure of precision can be calculated by means of the law of error propagation. From this view point the up-to-date treatments of the Braggs differentiated equation in the direct and reciprocal space is discussed and new approached.     

Über die Vorausbestimmung der thermoelastischen Eigenschaften von Halbleiter-Verbindungen

Extending some results of thermoelastic behavior of uniquely bonded crystal groups with constant Grüneisen-number γ to the field of strongly homologous intermetallic compounds (e. g. semiconductors, A^IIIB^V), it seems possible to predict the thermoelastic properties of those compounds, which are of unstable or otherwise non-investigable consistence.     

Über Strukturbeziehungen bei Erdalkalivanadin (IV,V)-oxiden

It is reported on compounds and their structural relations in the systems MeV^v-kO_3,5–k/2 with Me = Ca, Sr, Ba. The index k shows values from zero to one. According to the kind of Me-ions different phases are found. CaVO₃ und SrVO₃ crystallize in a perovskit-type. BaVO₃ crystallizes in a structure deriving from the Ba₃V₂O₈-type. X-ray analysis is confirmed by density- and NMR-measurements. Compounds of mixed oxidation numbers for Vanadium are only observed in the Ba and Sr-systems. Likewise their structures are derived from the Ba₃V₂O₈-type.     

Über die Bestimmung von Dotierungsprofilen in pnp-Siliziumhalbleitern mit der Elektronenstrahlmikrosonde

Everhart a. o. described a sentitive method of observing pn-junctions in semiconductor devices. When a semiconductor is bombarded by high energy electrons, electron hole pairs are generated within the bulk material. If the minority carriers cross the pn-junction before recombining, an electron beam induced signal (EBIC-signal) results with the maximum at the deplation region. If the charge carrier are generated in a distance larger than a few diffusion lengths from the junction, recombination will occur with little or no contribution to the output signal. At first a theoretical interpretation is given of the connection between the distribution of the space charge and an inverse voltage in the deplation layer of barrier in dependence on impurity density. It is followed by a mathematical method for careful analysis of the slopes and the amplitude of the EBIC-signal. The results were compared with the theorie. So it is possible to obtain informations on the profile of impurity density in the specimen. The use of the scanning technique with brightness modulation by the EBIC-signal allowed the demonstration of inhomogeneities in the diffusion front.     

Über die Züchtung von ZnS-, ZnSe- und ZnTe-Einkristallen unter Anwendung der chemischen Transportreaktion

In connection with investigations on the synthesis of ZnS, ZnSe and ZnTe single crystals by chemical transport using iodine as transport agent in sealed tubes the mechanism of mass-transport and the relationship between material-transport and growth process were studied. In this way the optimum conditions for growing single crystals were found. The dependence of the transport rate on the undercooling ΔT, on the diameter of the ampoule and on the pressure in the system is described. Relative large crystals in good quality could be propared by influencing the nucleation and the growth process by help of well defined transport rates. In all cases crystals with sphalerite structure only were obtained. The habit with the most common faces (110), (111) and (211) was found to be predominant. The dominant habit is responsive to variations in the experimental parameters. The crystal perfection have been determined by etch patterns and by X-ray topography.     

Über die Kristallstrukturdifferenzen der MeSO4 · nH2O-Salztypen

On the basis of the systematized data on the crystal structure of salts of the MeSO₄ · nH₂O type, where Me = Mg²⁺, Ni²⁺, Zn²⁺, Co²⁺, Fe²⁺, Cu²⁺ and n = 0–7, it is established that the differences in the structures of given chemical type metal sulphate crystal hydrates are determined by the nature of the metal ion. The differences in the crystal structure of the heptahydrate, as well as the existence or non-existence of crystal hydrates of some of the ions considered are explained with the electron configuration of the metal ions. The deformation trend of the octahedral coordination of the metal ions considered increases in the following way:      

Über die Flächenverteilung von Dekorationskeimen in der Umgebung von Versetzungen

Cleaved and evaporated faces of KCl:Me²⁺ single crystals were decorated with gold. The surface distribution of the decoration grains was investigated electron-microscopically. In the surroundings of the points of emergence of dislocations characteristic changes in the density distribution of the gold grains could be observed. They are described and discussed.     

Über das elektrolytische Wachstum und die Auflösung von Silbereinkristallen unter potentiostatischen Bedingungen. Einfluß der Zwillingsgrenzen

The rates of growth and dissolution of silver single crystals have been investigated under potentiostatic conditions. The results show that dissolution is more rapid than growth. That is explained with the effect of additional active centres in case of dissolution which have no noticeable influence on crystal growth rate. It is shown that twin boundaries have great influence on crystal growth rate. In the case of dissolution their effect is negligible and cannot be noticed. The asymmetry of the processes of growth and dissolution is stronger expressed in case of low values of potential, especially when crystals are of the normal type. The influence of twin boundaries on crystal growth rate increases with overvoltage.     

Über die röntgenographische Analyse der mittleren quadratischen Atomverschiebungen in einigen Halbleiterkristallen

X-ray measurements of the Debye-Waller factor were performed with single crystals of Ge and of semiconducting compounds A^IIIB^V, A^IIB^VI, A^IVB^VI in the temperature range 100 K — 1000 K. From the results the mean square atomic displacements 〈u²〉 and the Debye characteristic temperatures θ of the materials were calculated. Both parameters are discussed with respect to the influence of the temperature, the influence of point defects and, in the case of the compounds, deviations from the stoichiometric composition on the thermal lattice vibrations. Finally, considerations are presented, concerning the relationship between the parameters 〈u²〉 and θ_M, respectively, and the activation energies of vacancy formation and diffusion in the materials.