摘要
采用溶胶-凝胶技术,在Si(110)衬底上制备了Mg、Mn掺杂外延生长的Zn1-xMgxO和Zn1-xMnxO薄膜,通过XRD、AFM、PL等考察不同杂质浓度对薄膜结晶质量和发光性能的影响。结果表明:Zn1-xMgxO和Zn1-xMnxO薄膜均具有较高的Tc(002)结构系数和较为光滑、平整的表面形貌。掺杂使得薄膜的紫外发光峰向短波方向移动至365nm左右,同时Zn1-xMnxO薄膜的室温可见光发射得以有效地钝化,使其近带边紫外光发射与深能级可见光发射比例高达56,极大地提高了薄膜紫外发光性能。并对掺杂薄膜紫外发光蓝移和Zn1-xMnxO薄膜室温可见光发射的猝灭机理进行了深入探讨,得出掺杂组分为Zn0.85Mg0.15O、Zn0.97Mn0.03O时,薄膜具有最强的紫外光发射性能。
Zinc oxide （ZnO） semiconductor with a large exciton binding energy of 60 meV and a direct-band gap of 3.37 eV has attracted tremendous attention in recent years because of its high potential for applications, such as short wavelength optical devices, photonic devices and laser systems etc. Especially, the optical properties of ZnO can be obviously influenced by impurity doping with different concentrations, so several techniques, such as pulsed laser deposition, reactive thermal evaporation and sol-gel process, have been employed to synthesize high quality ZnO and doped-ZnO thin films. In this work, based on the fact that metal-doped concentrations have great influence on the crystal structure and ultraviolet （UV） emission of ZnO, such as Mg-doped and Mn-doped ZnO thin films, a consistent set of epitaxial n-type conducting Zn1-xMgxO and Zn1-xMnxO thin films were grown by sol-gel process on Si （110） substrates, and their crystal structures and radiation qualities influenced by different doping concentrations were studied. Meanwhile, the results of XRD, atomic force microscope （AFM） and photoluminescence （PL） spectrum indicated that the crystal structure, surface morphology and UV emission are sensitive to the doping concentrations. Compared with ZnO, Zn1 -x- MgxO and Zn1-xMnxO thin films tends to growth in c-axis-orientation, and a strong blue-shift UV emission peak at 365 nm appears both in Zn1-xMgxO and Znl-xMnxO. In particular, the visible emission of ZnO, which is typically due to the existence of surface defects and oxygen vacancies（Vo″） defects appears between 430 and 490 nm in the PL spectra. It is passivated in Zn1-xMnxO films at room temperature, which leads to that the UV emission qualities of Zn1-xMnxO thin films being greater as 56 times as the visible emissions in the optimal doping concentration. At the same time, the causes of blue-shift and Zn1-xMnxO＇s visible emissions passivation was studied, through the experiments it was indicated that Zn1-xMnxO＇s blue-shift UV emissions could be primarily caused by the Burstein-Moss （BM） effect, and the visible emissions passivation could be caused by the reduction of Vo″ defects induced by the Mn oxide. At last, the optimal doping concentrations of Zn0.85Mg0.15O and Zn0. 97Mn0.03O were demonstrated, which displays the strong blue-shift UV emissions and the best UV emission qualities.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2009年第5期624-629,共6页
Chinese Journal of Luminescence
基金
西安应用材料创新基金(XA-AM-200512)资助项目
作者简介
作者简介：吕婷（1983-），女，陕西渭南人，主要从事ZnO半导体材料的溶胶一凝胶法生长及相关特性的研究。E-mail：lvting709@163．com
