应用水热法制备了注射器样纳米结构氧化锌样品,室温下测量其真空场发射特性.根据测量数据,基于Fowler-Nordheim方程,估算了场发射效应增强因子,观察到增强因子随外加电压增加取值的两阶段性;结合样品的光致发光谱和能量散射谱,应用半导体材料中强场效应理论,结合场发射电流密度测量系统的串联电路等效,研究样品中空位对场发射特性影响机理.结果表明,制备过程中形成的锌、氧空位,在样品中产生了相当于杂质态的缺陷能级,缺陷能级与样品形貌共同作用,使样品较大的增强因子随场强增加而阶跃性下降.最后,用电化学沉淀法和气相传输法制备的纳米氧化锌样品的场发射特性,对上述分析结果进行验证.
Injector-like nanostructure samples of ZnO, which are synthesized by hydrothermal method, are experimentally investigated for the field emission (FE) properties, especially the current density varying with the intensity of the applied electric field; and the fascinating two-stage behavior of electric field enhancement factor (β) is observed. The good performance and the two-stage behavior of the 13 are explained based on the combination of the intensive electric field effect in semiconductor and its influence on the Fermi energy level with the effective series connection circuit of FE detection systems. Finally, the previous analysis conclusion is well experimentally demonstrated by the FE properties and PL spectra of Znic oxide nanostrucutres fabricated by electrochemically deposition and vapor phase transmitting methods, separately.