Low-macroscopic field emission from fibrous ZnO thin film prepared by catalyst-free solution route R. Maity, A.N. Banerjee, K.K. Chattopadhyay * Department of Physics, Jadavpur University, Kolkata 700032, India Accepted 24 April 2004 Available online 17 June 2004 Abstract Fiber-structured zinc oxide thin films were synthesized by catalyst-free chemical process from zinc acetate dihydrate at an elevated temperature of 1073 K on Si substrate. X-ray diffraction spectra confirmed the proper phase formation of the films. Scanning electron micrograph depicted the formation of ZnO fibers with an average diameter of 500 nm with an average aspect ratio 150. Field emission properties of the film showed considerably low turn-on field around 1.4 V/mm. This low-threshold field-emission of the films are attributed to the conducting nanostructure inside the film as well as on the tip of the fibers at the film–vacuum interface, which causes the geometrical field enhancement at the emitter-tip and provides the required barrier field for field-emission tunneling. The emission current was as high as 70 mA at the field of 3.6 V/mm. The high emission current, high stability and low turn-on field make the ZnO fibers a strong candidate for field-emission displays. # 2004 Elsevier B.V. All rights reserved. PACS: 79.70.þq; 81.16.Be; 81.07.Bc Keywords: Field emission; Low-threshold; ZnO fiber-structured; Solution method 1. Introduction Field emission displays (FED) and vacuum micro- electronic devices have recently attracted attention for low power panel application because of their thin profile, high production efficiency, fast response, high brightness, wide operating temperature range, possi- ble expansion of size and last but not the least, excellent picture quality at lower cost [1,2]. During the last decade, the advent of low-macroscopic field (LMF) emission from carbon based films, such as diamond, diamond like carbon (DLC), amorphous carbon (a:C) etc. [3,4], made them the candidate materials for FEDs. But recently, nanostructured materials, specially, quasi one-dimensional (1D) materials like carbon nanotubes (CNT) and nanofibres [5,6], Si-C nanorods and nanowires [7,8], ZnO nano- wires, nanotips, nanoneedles [9–13], etc. showed low- macroscopic field emission with considerable low- threshold and become strong candidates for FEDs. Emitter-tip geometry plays an important role in the low-macroscopic field emission mechanism. Sharp- tips with diameter of several nanometers, provide the necessary enhancement of the macroscopic field at the emitter-tip and therefore, supplies the required barrier- field (also called local field at the emitter-tip) to produce field emission tunneling. Hence, quasi 1D Applied Surface Science 236 (2004) 231–235 * Corresponding author. E-mail address: kkc@juphys.ernet.in (K.K. Chattopadhyay). 0169-4332/$ – see front matter # 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2004.04.037