LAUSR

Abstract ZnO/Al2O3 nanocomposite tetrapods (T-ZnO/Al2O3) with different thickness of Al2O3 film were fabricated by thermal evaporation ZnO tetrapods (T-ZnO) followed by atomic layer deposition (ALD) of Al2O3. The effects of Al2O3 on the optical and field emission properties of T-ZnO were investigated. The results show that the deposition of Al2O3 on the surface of T-ZnO will introduce surface defects between the T-ZnO and Al2O3 interfaces, leading to the decrease of the turn on field. However, with the further increase of Al2O3 thickness, the field emission properties deteriorate. The T-ZnO/Al2O3 with one ALD Al2O3 cycle exhibited the lowest turn-on field of 1.37 V/μm and the highest field enhancement factor of 6427. The post-annealing treatment will further improve their field emission properties due to the incorporation of Al in the ZnO.