【作者】 王秀华；

【导师】 刘肃；

【作者基本信息】 兰州大学 ， 微电子学与固体电子学， 2008， 硕士

【摘要】 ZnO是一种重要的宽禁带隙（Eg=3.3eV）半导体材料,它的激子束缚能高达60meV。因此,氧化锌材料在紫外光电器件方面有巨大的应用潜力。近年来在短波长发光器件、光探测器件以及抗辐射、高频和大功率电子器件方面的发展十分迅速。目前,有关氧化锌研究部分主要集中在低维氧化锌纳米材料的制备、紫外激光发射和可见发光机制等方面。首先,本文中我们采用电场辅助电化学沉积法,利用阳极氧化铝模板（AAO）,使用0.00166 mol/L的Zn（NO3）₂,0.0125 mol/L NaNO3水溶液制备了高度择优取向的ZnO单晶纳米线。X射线衍射仪（XRD）、隧道电子显微镜（TEM）、选取电子衍射（SADE）、X射线光电子能谱（XPS）对所得样品的结构、形貌以及化学组分分析表明,所得纳米线是沿（101）择优取向的六方纤锌矿结构单晶氧化锌纳米线,纳米线长约几十微米、直径约70～120nm。在PL谱中,除了有典型的ZnO纳米线强紫外（UV）发光峰和较弱绿光发光峰外,还有在412～430nm处的新的强蓝光发光峰和在464 nm处的蓝绿光发光峰。在617nm处还有一尖锐的、光强较强的红光发光峰。其次,我们采用相同的制备方法,使用0.00125 mol/L的Zn（NO₃）₂,0.0125mol/L Na₂S水溶液制备了高度择优取向的硫掺杂ZnO单晶纳米线。XRD、TEM、SADE对所得样品的结构、形貌分析表明,所得纳米线S掺杂前后纳米线直径没有明显的变化,约70～120 nm,长度约几到几十个微米;掺杂前纳米线较光滑,S掺杂后在一些局部区域ZnO纳米线的直径有了一定的增加。XPS对化学组成的分析进一步证实掺杂硫原子的存在。用PL谱对S掺杂前后的ZnO纳米线进行光学特性测量发现,S掺杂较大地改变了ZnO纳米线的发光性质。除了有典型的ZnO纳米线在378、392nm处的强紫外发光峰和在507、533 nm处的较弱绿光发光峰外,还有在406、420、434nm处的新的强蓝光发光峰和在456 nm处的蓝绿光发光峰。与ZnO纳米线光致发光谱相比,在617nm处尖锐的、光强较强的红光发光峰消失。最后,研究了ZnO纳米线发光机制及硫掺杂对ZnO纳米线发光性质的影响。对比发现,当S取代ZnO中O的位置,近带边发射（NBE）会产生的蓝移,且光强增大。深能级发射强度稍有降低。近带边与深能级发射强度之比增大,说明带边本征紫外发射并没有由于硫掺杂而被抑制。更多还原

【Abstract】 Zinc oxide（ZnO）is an interesting wide band gap（3.3eV）semiconductor material with a binding energy of 60 meV.It makes more attention to the ultraviolet optoelectronic devices.In recent years,it has developed rapidly,main due to its promising applications in short-wave light-emitting devices,photodetectors,as well as antiradiation,high frequency and high-energy electronic devices.Up to now,ultraviolet lasing emission,the visible emission and properties of ultradetector of ZnO have became the main topics of much researchs.Zinc oxide（ZnO）nanowires have been successfully synthesized by an electric field-assisted electrochemical deposition in porous anodized aluminum oxide template at room temperature.The consistency of NaNO3aqueous solution was 0.0125M,and the consistency of Zn（NO3）₂ aqueous solution was 0.00166M.The structure,morphology, chemical composition and photoluminescence properties of the as-synthesized ZnO nanostructures were investigated.X-ray diffraction（XRD）and the selected area electron diffraction（SAED）results reveal that the as-synthesized products are single phase with hexagonal wurtzite structure with a highly preferential orientation in the（101）direction. Transmission electron microscopy（TEM）observations indicate that the nanowires are uniform with an diameter of 70-120 nm and length up to several tens of micrometers. Room-temperature photoluminescence（PL）is observed in the ZnO nanowires which exhibit strong NBE ultraviolet peaks and week green emissions.A violet emission at 464 nm and blue emissions at around 412-430 were also observed in the PL spectrum for the as-synthesized ZnO nanowires.The PL spectrum also exhibits a strong red peak at 617 nm.Sulfur-doped zinc oxide（ZnO:S）nanowires have been also synthesized by the same method.The consistency of Na₂S was 0.0125 M,and the consistency of Zn（NO₃）₂ was 0.00125 M.The structure,morphology,chemical composition and photoluminescence properties of the as-synthesized ZnO:S nanostructures were investigated.XPS further reveals the presence of S in the ZnO nanowires.Room-temperature PL is observed in the sulfur-doped ZnO nanowires which exhibits strong NBE ultraviolet peaks at 378 nm and 392 nm and week green emissions at 533 nm and 507 nm.A violet emission at 456 nm and blue emissions at around 406,420 and 434nm were also observed in the PL spectrum for the as-synthesized ZnO:S nanowires.The strong red peak at 617 nm disappeared in the PL spectrum.The result of the PL spectrum showed that S-doping had an obvious effect on the luminescence property of typical ZnO nanowires.In addition,the luminescence mechanism of ZnO nanowires at room temperature was discussed.The influence of S incorporation on luminescence property of ZnO nanowires was also discussed.The PL spectra of the nanowires at room temperature reveals that the PL spectrum of S-doped ZnO nanowires experiences blueshift compared to that of the pure ZnO nanowires and the intensity changes of PL spectrum can be discovered.更多还原