Nanoporous ZnO film grown on sapphire by chemical vapor deposition

Without template, nanoporous zinc oxide (ZnO) film was grown on sapphire in a homemade chemical vapor deposition system under atmospheric pressure. In large area, the uniform pores have almost equal inner diameters of 500 nm and the figurations of the pores are quasi hexagons. The wurtzite crystalline structure and preferred (0001) orientation of the nanoporous ZnO film were confirmed by X-ray diffraction. The high element purity and optical quality were testified by the strong E ₂ vibration modes in Raman scattering and the sharp ultraviolet emission at 380 nm in photoluminescence, respectively. These results show a potential method for fabricating nanoporous ZnO film at low cost.