Highly controllable and reproducible ZnO nanowire arrays growth with focused ion beam and low-temperature hydrothermal method

Graphical abstract: - Highlights: • High-quality ZnO nanowire arrays with controllable degrees over size, orientation, uniformity and periodicity were fabricated on GaN substrate with focused ion beam etching and low-temperature hydrothermal method. • The influence of patterned growth holes (shape, depth, size and period) on the final morphology of ZnO nanowire arrays was carefully investigated and discussed. • Possible mechanism was proposed to interpret the growth process in and out of the pattern holes. - Abstract: In this work, high-quality ZnO nanowire arrays with controllable degrees over size, orientation, uniformity and periodicity are fabricated on GaN substrates with focused ion beam etching and low-temperature hydrothermal method. Experimental results revealed that the patterned holes (i.e., shape, depth, size and period) have decisive impacts on the morphology of resulting arrays. Optimal conditions and ordered arrays are obtained in terms of functionality analysis for both patterned holes and hydrothermal method. A possible mechanism is proposed to interpret the growth process in and out of the pattern holes. Results show that this hybrid method exhibits good reproducibility for the fabrication of high-quality ZnO nanowire arrays with great potentials