Formation of filamentary zinc oxide crystals on sapphire substrates placed on the target during hot sputtering
Results on a deposition of ZnO by dc-magnetron sputtering on (0001)-sapphire substrates placed on the surface of a "hot" ZnO target and on the water-cooled magnetron base near the target are shown. Formation of a well-oriented ZnO wiskers array on the substrate placed on the "hot" target was found. In the same time, in the case of growth on a substrate placed on the water-cooled magnetron base plate next to the sputtered target, formation of a continuous ZnO film with a well developed surface was observed. The crystal perfection of this film was worse than that of the whisker array grown on the substrate placed directly on the target. The sample grown on the surface of the “hot” target had a narrower and less wide band compared to the sample grown next to the target. The obtained results can serve as stimulus for further study of the processes of the uncatalyst formation of the well-oriented ZnO wiskers array on various substrates placed on the surface of a "hot" ZnO target near the target erosion zone with wide variations of technological parameters (working gas composition and pressure, power, etc.) and possible scaling of the process (up to tens of cm<sup>2</sup>).