Self-organized ZnMgO nanocolumns with ZnO/ZnMgO quantum wells on c-plane Al2O3 substrates by MBE: Growth conditions and properties

Abstract

One dimensional zinc oxide nanostructures have great potential for applications in the fields of optoelectronic and sensor devices. In this paper, we present the synthesis of ZnO/ZnMgO heterostructures on c- plane Al2O3 by plasma-assisted molecular beam epitaxy and investigation of their structural and optical properties. We demonstrate that it is possible to grow a good quality nanocolumns on c- plane Al2O3 substrate without employing a catalyst such as Au or Ag. We have also studied a shift between polar- and nonpolar- ZnO/ZnMgO quantum wells. The non-polar a- plane ZnO/ZnMgO nanocolumns were achieved on r- plane sapphire substrate, while the on polar c-plane substrate was used to obtain a polar c-orientation of the nanostructures.