摘要:

AbstractFormulae are derived for the excess free energy of cylindrical and pill‐box nuclei under homogeneous and heterogeneous conditions. The surface free energy is taken to be different for lateral and end surfaces of the nucleus in deriving the critical dimensions. The effect of pressure on the formation of a nucleus is studied theoretically first for the appearance of a new phase from a gas and then for a condensed phas

ISSN:0023-4753    

DOI:10.1002/crat.19790140402

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractCuInS2thin films with thicknesses in the range of 500 Å were deposited onto semi‐insulating (111) A‐oriented GaAs substrates by flash evaporation in the substrate temperature rangeTsub= 570 … 870 K. Epitaxial growth begins atTsub= 645 K. The films had always the chalcopyrite structure. Indications to a transition from the chalcopyrite phase to the sphalerite phase were observed atTsub= 870 K. Films grown atTsub≦ 800 K showed n‐type conductivity whereas at growth temperaturesTsub≧ 850 K the films were always p‐type conducting. A donor level and an acceptor level with ionization energies of 0.24 eV and 0.22 eV, respectively, were found from an analysis of the electrica

ISSN:0023-4753    

DOI:10.1002/crat.19790140403

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractCrystallization processes of binary systems are considered, in which solid particles consisting of components A and B grow from the melt in monolayers of a two‐phase boundary zone by a mechanism of spontaneous thermal equilibrium type concentration fluctuations. The calculation is based on probability distribution functions. The region of small supercoolings of the binary system melt‐crystal proves most valid for this investigation. The change of the mean crystallization rate of the two‐phase boundary zone with the supercooling of the melt shows a linear behaviour. The dependence of the kinetic coefficient on the degree of the atomic roughness of the phase boundary with different numbers of monolayers in the phase boundary, the total number of particles in each monolayer, and a certain roughness are connected with the energy of positional disorder in binary sy

ISSN:0023-4753    

DOI:10.1002/crat.19790140404

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractInxGa1–xAs films withx= 0.03 and 0.05 were grown from an InGaAsP liquid phase. Because of high value of distribution coefficient of P we have heterojunction GaAsInyGa1–yPzAs1–x–InxGa1–xAs. The influence of Phosphorus atom fraction (Xp) in liquid phase on dislocation density in the top InxGa1–xAs layer was studied. It was found that dislocation density (Nd) as a function ofXpis a curve with some minima. The minima ofNdfor substrates of (111) A and (111) B orientations are observed in the different intervals ofXpaxis. — The width ofNdminimum is decreased if the substrate is misoriented from the (111) plane. — It was supposed that the clusters exist in the liquid phase. On the basis of this assumption one can explain the influence of substrate position over or under the melt on the film perfection. The diameter of these clusters is esti

ISSN:0023-4753    

DOI:10.1002/crat.19790140405

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractAnhand vorhandener experimenteller Daten der Gleichgewichte fest‐flüssig und flüssig‐gasförmig des Systems InAs wurde überprüft, inwieweit die Modelle von BREBRICKund KRUPKOWSKIsowie die QCE‐Näherung diese widerspruchsfrei beschreiben können. Das KRUPKOWSKI‐ und das BREBRICK‐Modell sind als thermodynamisch konsistent einzuschätzen. Aufgrund des einfacheren Ansatzes sollte das KRUPKOWSKI‐Modell bevorz

ISSN:0023-4753    

DOI:10.1002/crat.19790140406

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractThe shape of the empirical incorporation characteristic of phosphorus in epitaxial silicon, deposited from silane‐phosphine‐hydrogen mixtures, shows two branches with different incorporation dependences on temperature (incorporation enthalpies). In the lower phosphorus‐concentration range (N P Si +1018) the incorporation equilibrium of the dimeric phosphorus molecules, formed by the nearly complete decomposition of phosphine, is reflected in the incorporation enthalpy of the empirical incorpo

ISSN:0023-4753    

DOI:10.1002/crat.19790140407

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractMit Hilfe der Methode der physikalisch‐chemischen Analyse werden die Systeme Mg(NO3)2Co(NO3)2H2O und Mg(NO3)2Ni(NO3)2H2O bei 25,0°C untersucht. Es wird festgestellt, daß als Folge isodimorpher Substitution der Mg2+‐Ionen von den Mg(NO3)2· 6 H2O‐Kristallen durch Co2+oder Ni2+‐Ionen oberhalb einer bestimmten Substitutionsgrenze Strukturä

ISSN:0023-4753    

DOI:10.1002/crat.19790140408

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractThe orientational order S of a dichroic dye dissolved in a liquid crystal has been determined in the nematic, smectic A and smectic B phase of 4‐n‐hexyloxybenzylidene‐4′‐n‐hexylaniline. The used method is based on the absorption measurement of unpolarized light in a homeotropic oriented liquid crystalline layer and in an isotropic layer. The orientational order of the dissolved molecules was compared with the order parameter of the liquid crystall

ISSN:0023-4753    

DOI:10.1002/crat.19790140409

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractMicrohardness of Hg2Cl2, Hg2Br2and Hg2I2single crystals has been measured on (001) and (110) faces using the indenter after Vickers. It has been found that the microhardness of the first two homologues differs only slightly whereas the iodide is considerably softer: by about 20% on the (001) face and by about 30% on the (110) face. The average microhardness value, calculated from the values obtained on gradually rotating the indenter over 360° on the (001) face, is for Hg2Cl2and Hg2Br2practically equal to the microhardness of NaCl (20.3 and 19.4 compared to 19.6 · 107Pa). The average microhardness of the (110) face is for Hg2Cl2and Hg2Br2about 2 × lower and for Hg2I2about 2.6 × lower than that of the (001) face. In the case of Hg2Cl2the microhardness of the (001) face has been also calculated from crystallochemical parameters and the results have been found to be in good agreement with the value obtained experimentally for the orientation of the indenter's diagonal parallel to the [100] direction, where the data is the least influenced by the elasticity of the sample (16.6 compared to 18.6 · 10

ISSN:0023-4753    

DOI:10.1002/crat.19790140410

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY

摘要:

AbstractThe variation in the microhardness of the magnesium orthosilicate crystals has been determined using Vicker's microhardness indentor. The length of the rays of dislocation rosettes around the indentation, obtained by etching the indented cleavages have been measured. It is observed that: (i) irrespective of the relative orientation of the indentor and the crystal, the median vents initiated at the sharp indentation edges, (ii) the microhardness of the crystals depends on the applied load, and (iii) the microhardness of the crystal is independent on the duration of loading. The implications are discussed.

ISSN:0023-4753    

DOI:10.1002/crat.19790140411

出版商:WILEY‐VCH Verlag    

年代:1979

数据来源: WILEY