Periodically polarity inverted (PPI) ZnO templates were fabricated using molecular beam epitaxy by employing MgO buffer layers. The polarity of ZnO film was controlled by the transformation of crystal structure from hexagonal to rocksalt due to the thickness of the MgO buffer layers. The polarity of ZnO in the PPI template was confirmed by AFM and PRM measurement. Higher growth rate and lower current value under positive supplied voltage in the region of Zn-polar were measured with comparing to that of O-polar. Holographic lithographic technique was employed for the realization of submicron pattern of periodical inverted polar ZnO over large area. After reaction using a carbothermal reduction, spatially well-separated ZnO nanorods with pitch of submicron were only observed in the Zn-polar regions. The possible reason for the difference of surface characteristics was considered as being due to the configuration of dangling bonds according to polarity.

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Well aligned ZnO nanowall arrays with submicron pitch were grown on a periodically polarity-inverted ZnO template using a carbothermal reduction process. Under the conditions of a highly dense Au catalyst for increasing nucleation sites, ZnO nanowalls with a thickness of 126 +/- 10 nm, an average height of 3.4 microm, and a length of about 10 mm were formed on the template. The nanowalls were only grown on a Zn-polar surface due to a different growth mode with an O-polar surface. The results of x-ray diffraction and photoluminescence (PL) measurements revealed a single crystalline, vertical alignment on the template, and a large surface to volume ratio of the ZnO nanowalls.