English: Surface image of porous indium phosphide synthesised on the surface of a single crystal with surface orientation (111) by electrochemical etching in a hydrofluoric acid solution.

The image was obtained on a JSM-6490 microscope by researchers of Berdyansk State Pedagogical University. Colour processing was performed with the help of Adobe Photoshop. This micrography presents significant scientific value. The flower-like structures that look like gems are indium oxides formed on the surface of the nanostructure during electrochemical treatment and after its completion. The formation of oxide crystallites indicates the presence of active surface states. We can observe a striped pore distribution. The pores grow in streaks instead of covering the entire surface of the crystal. This outstanding phenomenon called segregation appears due to the uneven distribution of impurities. The appearance of segregation streaks is associated with the quite popular technology of growing crystals using the Chokhralsky method. We can see streaks in the longitudinal plane, but there are corresponding inhomogeneities of the impurity distribution in both dimensions, they hinge on the crystal growth modes. Physically, the streaks can be explained by the presence of long-range stresses that occur at the interface between the melt and the solid-formed semiconductor's phase. Compositional heterogeneity can be considered as an uneven distribution of impurities resulting in dislocations of the crystal lattice. It should be noted that the study of segregation streaks is a priority technological task. But such streaks are not always easy to detect. Electrochemical etching of a semiconductor in a selective solvent is a promising and reliable method for observing the compositional perfection of crystals.

Its authors are Yana Sychikova (synthesis of nanostructures) and Serhii Kovachov (colour design).

English: Gems NanoArt.Surface image of porous indium phosphide synthesised on the surface of a single crystal with surface orientation (111) by electrochemical etching in a hydrofluoric acid solution.