Huang Jheng-Ming, Tsai Shang-You, Ku Ching-Shun, Lin Chih-Ming, Chen San-Yuan, Lee Hsin-Yi
Program for Science and Technology of Accelerator Light Source, National Chiao Tung University, Hsinchu 300, Taiwan.
National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan.
Phys Chem Chem Phys. 2016 Jun 1;18(22):15251-9. doi: 10.1039/c6cp01011c.
The electrical properties and field-emission characteristics of ZnO nanowires (ZnO-NWs) fabricated using a vapor-liquid-solid method were systematically investigated. In particular, we explored the effects of Al-doped ZnO (AZO) films (thickness 4-100 nm) deposited on ZnO-NWs using an atomic layer deposition (ALD) method on the optoelectronic properties. The results show that the sheet resistance of net-like ZnO-NW structures can be significantly improved, specifically to become ∼1/1000 of the sheet resistance of the as-grown ZnO-NWs, attaining less than 10 Ω Sq(-1). The emission current density measured at the maximum field was roughly quadrupled relative to that of the as-grown ZnO-NWs. The data of the enhanced field-emission characteristics show that, with the ALD system, the AZO films of small resistance are readily coated on a structure with a high aspect ratio and the coating radius is controlled relative to the turn-on voltage and current density. The ultrathin AZO film from a one-monolayer coating process also significantly improved emission properties through modification of the effective work function at the AZO/ZnO-NW surface.
系统研究了采用气-液-固方法制备的ZnO纳米线（ZnO-NWs）的电学性能和场发射特性。特别地，我们探讨了使用原子层沉积（ALD）方法沉积在ZnO-NWs上的Al掺杂ZnO（AZO）薄膜（厚度4-100nm）对其光电性能的影响。结果表明，网状ZnO-NW结构的薄层电阻可得到显著改善，具体而言变为生长态ZnO-NWs薄层电阻的约1/1000，达到小于10Ω Sq(-1)。在最大场强下测得的发射电流密度相对于生长态ZnO-NWs的发射电流密度大致增加了四倍。增强场发射特性的数据表明，利用ALD系统，低电阻的AZO薄膜易于涂覆在高纵横比结构上，并且相对于开启电压和电流密度可控制涂覆半径。单层涂覆工艺制备的超薄AZO薄膜还通过改变AZO/ZnO-NW表面的有效功函数显著改善了发射性能。
