In-doped zinc oxide dodecagonal nanometer thick disks

In-doped ZnO nanometer thick disks were successfully fabricated by thermal evaporation of a powder mixture of Zn, In2O3 and graphite without catalyst. SEM images show that some ZnO disks have perfect dodecagon shape. These disks are about 1 similar to 3 mu m in size and 40 similar to 100 nm in thickness. XRD, TEM and EDS observations show that the disks are single-crystalline ZnO with wurtzite structure. The disks grow mainly along the twelve symmetric directions of < 2 (1) over bar(1) over bar0 > and < 10 (1) over bar0 >, while the growth along [0001] is suppressed. The In content of the disks reaches 27.4 at. %. Room temperature photoluminescence spectra show that the UV emission peak blueshifts and become broader after doping. (c) 2006 Elsevier B.V. All rights reserved.