Multiple GaInN quantum wells (QWs) were grown on facets with reduced piezoelectric fields (PFs) of selectively grown GaN stripes oriented along the ⟨11¯00⟩ and ⟨112¯0⟩ directions by metalorganic vapor phase epitaxy. We found a higher normalized growth rate for the GaInN QWs on the {11¯01} facets compared to the {112¯2} facets and the planar grown reference sample on unstructured template. The different luminescence wavelengths observed for the QWs on these different facets can partly be explained by the reduced PFs, but additionally indicate that the In incorporation efficiency depends on the facet type. On stripes with trapezoidal cross section, we found strong interfacet migration of In and Ga changing the local thickness and composition significantly.

We report on reflected high-energy electron-diffraction and transmission electron microscopy plane-view investigation of the dislocation structure in doped and undoped ZnSe/GaAs(001) grown by molecular-beam epitaxy and metal-organic vapor-phase epitaxy. The thicknesses of the investigated layers vary between 60 and 900 nm. Several stages of dislocation formation are found which occur at distinct layer thicknesses. Frank partial dislocations (up to 500 nm), Shockley partial dislocations (between 130 and 400 nm) with a maximum density at 300 nm, and perfect 60° dislocations (above 300 nm) are observed in samples with perfectly smooth surface. The formation of Shockley partial dislocations is strongly anisotropic which might be due to the higher mobility of α-type dislocations. An increased roughness of the growing surface yields a suppression of Shockley partial dislocations and an irregular dislocation network with dislocations inclined to the 〈110〉 directions. A regular dislocation network with straight dislocations is found in Cl-doped samples.

We have studied the growth of GaInN/GaN quantum wells on various polar, nonpolar and semipolar planes. From a detailed x-ray diffraction analysis, we derive the strain state and the composition of the quantum wells. The optical emission energy is obtained from photoluminescence spectra and modelled taking into account the deformation potentials and the Stark shifts. Both x-ray and optical data consistently show that indium incorporation is identical on the polar, nonpolar and semipolar planes within the experimental uncertainty.

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In this work we present pair distribution functions (PDFs) of amorphous Fe1-xTbx (x=0.1-0.5) with a high spatial resolution better than 0.02 nm obtained from electron diffraction experiments. The short-range order of FeTb alloys with up to 32 at.% Tb content is described quantitatively as an arrangement of the known crystalline FeTb phases with various concentrations and structures by superposing PDFs of these structures in the range of the first and second coordination shell up to 0.6 nm. Partial FeFe, FeTb and TbTb radial distribution functions (RDFs) are obtained from this model; coordination numbers and neighbour distances are presented and compared to other authors' results.