Structure and magnetic properties of Si0.97Ge0.03 whiskers

Abstract

By the method of chemical transport reactions in the closed halogen system Si-Au-Pt-B-Br, whiskers Si<sub>1-x</sub>Ge<sub>x</sub> x = 0.01-0.08 of transverse dimensions 0.1-100 μm were grown. Structural and magnetic properties of the obtained crystals are investigated. The method of scanning electron microscopy showeds that on the surface of needle-like crystals, with transverse dimensions of 50-80 microns, a porous shell with a thickness of 50-60 nm is present. From the analysis of the energy spectra of X-rays, it was found that the surface shell contains significant concentration atoms of oxygen and of carbon. In turn, oxygen and carbon peaks were not detected on the inner layers of samples. It has been established that the chemical etching of the surface layer of crystals leads to the improvement of their structural and magnetic properties.