退火气氛对铽掺杂氧化锌纳米薄膜发光性能的影响

Effect of annealing atmosphere on photoluminescent properties of Tb doped zinc oxide thin films

以Zn(Ac)_2 2H_2O和Tb_4O_7为原料,采用溶胶-凝胶、浸渍-提拉技术在单晶硅(100)衬底上制备了铽掺杂的氧化锌(ZnO∶Tb)薄膜。分别在氮气和氢气气氛下对薄膜进行退火处理,并进行了XRD、IR、EDS和AFM表征,同时结合荧光光谱测试详细研究了退火气氛对薄膜发光性质的影响。结果表明,经氮气和氢气气氛处理的薄膜中,ZnO∶Tb粒子均具有六方纤锌矿结构,且排列致密均匀,相应的ZnO∶Tb粒径分别为59和45 nm。经氮气气氛处理的ZnO薄膜,掺杂前后的发光情况变化显著,由485 nm的蓝光发射移到382 nm的紫外发射。用氢气进行退火处理时,掺杂前后薄膜的荧光光谱都由强的紫外发射和弱的蓝光发射组成,但掺杂后薄膜的紫外光发射减弱,蓝光发射增强。薄膜层数为3、Tb掺杂量为3.85 mol%时,ZnO∶Tb薄膜的荧光发射效果最佳。

Tb doped zinc oxide （ZnO： Tb） nano thin films were prepared on Si （100） substrates by a sol-gel method and followed by dip-coating with Zn（Ac）2·2H2O and Tb4O7 as the raw materials. The ZnO： Tb films were annealed in N2 and H2 atmospheres respectively, and were characterized by XRD, IR, EDS and AFM, respectively. The effect of annealing atmospheres on photoluminescent properties of films was investigated by photoluminescent spectroscopy. The results indicated that ZnO： Tb films an- nealed in N2 or HE atmospheres had a hexagonal wurtzite structure and packed compactly and uniformly, in which the particle sizes were 45 and 59 nm, respectively. The photoluminescence of ZnO： Tb films an- nealed in N2 obviously changed compared with un-doped ZnO and the emission peak shifted from blue band （485 nm） to ultraviolet band （382 nm）. The photoluminescent spectra of ZnO： Tb films and pure ZnO were composed of both strong ultraviolet band and weak blue band. When they were treated in Ha,the ultraviolet band decreased and the blue band increased for ZnO： Tb films. The photgluminescent e-mission of ZnO： Tb films performed best when the layers of thin films were three with the Tb content of 3.85 mol%.