膜厚对射频磁控溅射法制备的SnS薄膜结构和光学性质的影响

利用射频磁控溅射法在玻璃衬底上制备SnS薄膜,用X射线衍射(XRD)、能谱仪(EDS)、原子力显微镜(AFM)、场发射扫描电镜(FE-SEM)和紫外-可见-近红外分光光度计(UV-Vis-NIR)分别对所制备的薄膜晶体结构、组分、表面形貌、厚度、反射率和透过率进行表征分析。研究结果表明:薄膜厚度的增加有利于改善薄膜的结晶质量和组分配比,晶粒尺寸和颗粒尺寸随着厚度的增加而变大。样品的折射率在1 500~2 500 nm波长范围内随着薄膜厚度的增加而增大。样品在可见光区域吸收强烈,吸收系数达10⁵ cm^-1量级。禁带宽度在薄膜厚度增加到1 042 nm时为1.57 eV,接近于太阳电池材料的的最佳光学带隙(1.5 eV)。

Effect of Thickness on The Structure and Optical Properties of SnS Films Fabricated by RF Magnetron Sputtering

SnS thin films were prepared on glass substrates by RF magnetron sputtering technique. The crystalline structure, composition, surface morphology, film thickness, transmittance and reflectance of the films were characterized by XRD, EDS, AFM, FE-SEM and UV-Vis-NIR spectroscopy, respectively. The results show that the increase of thin film thickness helps to improve the crystalline quality and component ratio of the film, and the grain sizes and particle sizes increase with the increasing of the film thickness. The refractive index of the sample increases with the increasing of film thickness in the wavelength range from 1 500 to 2 500 nm. The samples have strong absorption in the visible light region with the absorption coefficients of 10⁵ cm^-1 order. The energy bandgap (E_g) of the film with thickness of 1 042 nm is 1.57 eV, closes to the best optical bandgap of the solar cell materials(1.5 eV).