Ga-N共掺氧化锌纳米线阵列制备及发光性能研究

摘要

Ga-N codoped ZnO nanowire arrays were synthesized on c-sapphire substrate by chemical vapor deposition (CVD) method, using NO gas and Ga2O3 powder as doping sources. The as prepared Ga-N codoped ZnO nanowire arrays were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectra. The results show that Ga-N codoped ZnO nanowire arraysare hexagonal wurtzite structure with the orientation of (002) direction. Both Ga and N atoms are uniformly doped in ZnO nanowires,whichis demonstrated by scanning transmission electron microscopy (STEM) measurement.Furthermore, the morphology of the doped ZnO nanowiresare transformed from hexagonal structure to cone type with the increase of doping contents, and the average length of ZnO nanowires decreases from 2 μm to 1 μm at the same time. XPS measurements show that the Ga 2p, Zn 2p and N 1s peaks are shifted to lower binding energy after doping in ZnO nanowires.The optoelectronics properties of the Ga-N codoped ZnO nanowires were also evaluated by PL spectra. The results show that the near-band edge UV emission peak and green emission peakare detected. In addition, the PL peaks positionsare shifted and the intensity rate of UV/Vis peaksis varied by changing the doping contents.%采用化学气相沉积法(CVD)以一氧化氮(NO)和氧化镓(Ga2O3)为掺杂源,在c轴取向单晶蓝宝石衬底上外延生长镓氮(Ga-N)共掺氧化锌(ZnO)纳米线阵列.利用SEM,XRD,HRTEM,XPS,PL等测试手段对掺杂后的ZnO纳米线阵列进行结构、成分和光学性能表征.结果表明,Ga-N共掺ZnO纳米线阵列保持六方纤锌矿结构,沿(002)方向择优生长;掺杂元素在样品中均匀分布.随着掺杂浓度增加,纳米线由六棱柱结构转变为尖锥层状结构,长度由2μm减小到1μm,锥度增加至0.95;N 1s/Ga 2p/Zn 2p峰结合能向低能态方向移动.PL光谱分析表明,所有样品均出现紫外发光峰和绿光发光峰,不同掺杂浓度的缺陷发光强度不同.