Field Emission and Photoluminescence Properties of Al-Doped T-ZnO Whiskers

Al-doped tetrapod-like ZnO(T-ZnO) films were fabricated using screen printing method to study their structures,surface morphologies,optical properties and field emission behaviors.All samples show typical photo luminescence(PL) behaviors with two emissions of a narrow UV peak centering around 373 to 383 nm and a green deep level peak centering around 510 to 540 nm.The green deep level PL emission is attributed to the defects in the T-ZnO films.The largest UV peak and the highest field emission were observed on 0.5 mol/L Al-doped T-ZnO films.The turn-on field and the threshold field of the T-ZnO films were 3.6 V/μm and 6.9 V/μm,respectively,and the enhance field factor was 30 249.