直流反应磁控溅射制备Zn1-xCdxO薄膜的结构和光学性能研究

摘要

利用直流反应磁控溅射的方法在玻璃衬底上沉积了（002）方向高度择优生长的纤锌矿结构的Zn1-x Cdx O（x =0，0.2）合金薄膜.利用 XRD、XPS、TEM、PL 对薄膜的结构和光学性能进行了详细研究.结果表明，随着 x =0到 x =0.2，（002）衍射峰从34.36°偏移到33.38°，（002）方向的晶面间距从0.260 nm 增加到0.268 nm，Zn1-x Cdx O 薄膜的光学带隙也从3.20 eV 减小到2.70 eV，相应的近带边发光峰从393 nm 红移到467 nm.另外，我们还从能带结构观点对 Zn1-x Cdx O 薄膜的发光机理进行了研究.%The ternary Zn1-x Cdx O( x = 0,0. 2)thin films with wurtzite structure and highly(002)-preferred orientations were deposited on glass substrates by the direct current(dc)reactive magnetron sputtering method. The X-ray diffraction( XRD),X-ray photoelectron spectroscopy( XPS),transmission electron microscopy (TEM),optical absorption spectra and photoluminescence(PL)were employed to investigate the structural and the optical properties in detail. Results indicated that as x varies from x = 0 to 0. 2,the diffraction angle of the (002)peaks decreased from 34. 36 to 33. 38° and the lattice spacing increased from 0. 260 to 0. 268 nm. Moreover,the optical band-gap of the Zn1-x Cdx O thin films with the wurtzite structure decreased from 3. 20 eV at x = 0 to 2. 70 eV at x = 0. 2. Correspondingly,the near-band-edge emission peak was red-shifted from 393 to 467 nm. In addition,the PL mechanism of the Zn1-x Cdx O alloy films was discussed in detail from the viewpoint of band structure.