利用脉冲激光沉积(PLD)在玻璃衬底上制备了Cu掺杂SnS薄膜。靶材是由SnS和Cu2S粉末混合压制而成(Cu和Sn的量比分别为0%、2.5%、5%、7.5%和10%)。利用X射线衍射(XRD)、拉曼光谱仪(Raman)、原子力显微镜(AFM)、紫外-可见-近红外分光光度计(UV-Vis-NIR)、Keithley 4200-SCS半导体参数分析仪研究了Cu掺杂量对SnS薄膜的晶体结构、表面形貌、光学性质和电学性能的影响。结果表明: 所制备的SnS薄膜样品沿(111)晶面择优取向生长,SnS∶5%Cu薄膜的结晶质量最好且具有SnS特征拉曼峰。随着Cu掺杂量的增大,平均颗粒尺寸逐渐增大。不同Cu掺杂量的薄膜在可见光范围内的吸收系数均为105 cm-1数量级。SnS∶5%Cu薄膜的禁带宽度Eg为2.23 eV,光暗电导率比值为2.59。同时,在玻璃衬底上制备了p-SnS∶Cu/n-ZnS异质结器件,器件在暗态及光照的条件下均有良好的整流特性,并具有较弱的光伏特性。

Cu doped SnS thin films were grown on the glass substrates by pulsed laser deposition. The targets were pressed by the mixture of SnS and Cu2S powder (Cu and Sn molar ratios were 0%,2.5%,5%,7.5%,and 10%,respectively). The effects of Cu doping content on the microstructural,morphological,optical and electrical properties of SnS thin films were studied by X-ray diffraction (XRD),laser Raman spectrometry,atomic force microscopy (AFM),ultraviolet-visible-near infrared spectrophotometer (UV-Vis-NIR),and Keithley 4200-SCS semiconductor parameter analyzer. The results show that the films grow preferentially oriented in (111) plane,and SnS∶5%Cu film has the excellent crystalline and Raman characteristic peaks. With the increasing of Cu doping content,the average particle sizes of the films increase. The absorption coefficient of the film in the visible region is the order of 105 cm-1 for different Cu doping content. The direct band gap of SnS∶5%Cu film is 2.23 eV,and the ratio of photo-conductivity to dark-conductivity is 2.59. Finally,p-SnS∶Cu/n-ZnS heterojuction device was fabricated on the glass substrate. The device exhibits good rectifying behaviors in dark and under illumination,and weak photovoltaic properties.