Search academic texts

Information × Registration Number 0211U006640, 0109U004505 , R & D reports Title Topological types and optical properties of the nanocrystal structures on the base of AIVBVI compounds popup.stage_title Head Freik Dmytro Myhaylovych, Registration Date 02-03-2011 Organization Precarpathian university named after Vassyl Stefanyk popup.description2 Topological and optical features of PbTe nanostructures of different thickness, which was grown on cleavages of mica, polyamide, polished glasses and gel films with different deposition temperatures, are studied. PbTe films on mica are characterized by the formation of nanostructures with rounded edges and without a clear faceting. With the deposition time increase and, accordingly, the condensate thickness increasing to (5.4-6.5) micrometers growth of well-formed nanocrystals of different heights (50-400) nm with linear dimensions of the basis for 1 micrometer takes place. PbTe nanostructured on the polished glass are closely packed layers of thin (<100 nm) plates, which are targeted mainly facet (100) parallel to the substrate surface. As the deposition temperature increases Ts = (373-498) K with transverse dimensions increase from (0.1-1.5) micrometers to (5-10) micrometers, and the land fuses. Results of atomic force microscopy of films, which are obtained on polyamide substrate, show that they are clearly structured. Thus with increasing of deposition time (thickness of the condensate) the size of nanostructures in lateralis and vertical directions increase. It is shown that the optical properties (spectrum of transmission, absorption and reflection) of IV-VI nanostructures are defined by character of condensate and its topological features. Steepness of the high-frequency edge of absorption and the value of transmission band is greater for ordered PbTe structures on (0001) mica-muscovite. For PbTe nanostructures on the polished glass spectrally selective character of the weakening of radiation of visible range and different reflection for (1250-1000) cm-1 region is detected. Topology of PbTe nanostructures on oxide gel-films of SiO2, GeO2 and HfO2 is defined by the temperature of precipitation and size of substrate heat conduction, and reflection spectrums are characterized by a significant increase for inverse wavelengths less than 1000 cm-1. Perspective directions of researches of lead chalcogenides nanostructures are specified. Product Description popup.authors Горічок Ігор Володимирович Дундза Богдан Степанович Ліщинський Ігор Мирославович Никируй Любомир Іванович Чав'як Іван Ігорович Яворський Ярослав Святославович popup.nrat_date 2020-04-02 Close