The growth of p-type ZnO film was realized for the first time by the simultaneous addition of NH3 in carrier hydrogen and excess Zn in source ZnO powder. The resistivity was typically 100 Ω·cm. A model showing nitrogen incorporation suggests the possibility of realizing p-type ZnO film of low resistivity by optimizing thermal annealing.

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Hall coefficient and resistivity measurements have been made on single-crystal ZnO films prepared by chemical vapor deposition on sapphire substrates from 4.2 K to 300 K. Successive reduction of the film thickness from the surface and the rear (interface to substrate) revealed that there are two regions–a bulk region and an interfacial region adjacent to the substrate. At the interfacial region, the carrier density is assumed to be very high and impurity-band conduction takes place. The dependence of the mean resistivity and the mean carrier density on the film thickness and temperature are described well by the two-layer and two-band model.

One-dimensional Thue-Morse (ThMo) lattices are examples of self-similar structures that exhibit bandgap phenomena. ThMo multilayers may also possess fractal photonic bandgaps that give rise to large omnidirectional reflectance and light-emission enhancement effects. Two-dimensional (2D) ThMo aperiodic quasicrystals possess interesting properties for photonic applications too. Here we demonstrate the experimental fabrication of large area 2D ThMo lattices into polymeric substrates at nanometre scale by electron beam lithography (EBL). Far field diffraction patterns of the experimental ThMo structures have been measured and compared with the calculated theoretical Fourier spectra. Scanning electron microscopy and far field diffraction are used to characterize the experimental structures.