化学浴法制备CdS薄膜及其光电性能研究

Study on Preparation and Photoelectric Properties of CdS Thin Films by Chemical Bath Deposition

本文用氯化镉、氯化铵、硫脲和氨水的溶液体系采用化学浴沉积法合成CdS薄膜,制备出均匀、致密的CdS薄膜,通过XRD、SEM、EDS、紫外可见吸收光谱等表征手段研究了CdS薄膜的晶体结构,表面形貌,元素比例和光电性能。发现在不同水浴温度下都成功制备了CdS薄膜,其中75℃制备的CdS薄膜最为均匀致密且其XRD衍射峰强度最强,光吸收边在500 nm附近,禁带宽度大约为2.52 eV。这些CdS薄膜的光电响应大,暗态及光照下的电导率分别为1×10-4S.cm-1和1.04×10-2S.cm-1。用它们制备的CdS/CZTS异质结太阳电池具有明显的光伏效应。

CdS thin films were prepared by chemical bath deposition（CBD） in an aqueous containing cadmium chloride,ammonium chloride,thiourea and ammonia.Uniform and compact CdS films were finally prepared.The crystalline structure,morphology,elemental analysis and optoelectronic properties of CdS films were investigated by XRD,SEM,EDS,and UV-vis-NIR spectroscopy.It was found that CdS thin films were successfully prepared at different bath temperatures.The CdS film prepared at 75 ℃ showed uniform and dense surface morphology and presented the strongest peak intensities of the XRD patterns and a photoabsorption edge near 500 nm with a band gap of about 2.52 eV.Moreover,the photoelectric response from the CdS films was large with the dark and light conductivity value of 1 × 10-4 S.cm-1 and 1.04 × 10-2 S.cm-1,respectively.In addition,the prepared CdS/CZTS hetero-junction solar cell demonstrated an obvious photovoltaic effect.