连续离子层吸附反应法制备(Zn,Cd)S薄膜及其性能

采用液相薄膜制备工艺——连续离子层吸附反应法(successive ionic layer adsorption and reaction，SILAR)，在室温下，使用混合阳离子前驱体于玻璃衬底上制备了(Zn，Cd)S薄膜．采用X射线光电子谱分析薄膜的成分，测定紫外透射光谱，分析不同成分对薄膜光电性能的影响，并使用环境扫描电镜对薄膜的表面形貌进行观察．实验结果表明：SILAR法制备薄膜的生长速率约为3nm／cycle。(Zn，Cd)S薄膜的成分偏离前驱体溶液中的n(Zn)／n(Cd)值，表现为Cd含量偏大，这与CdS和ZnS二者的溶度积不同有关。随着Cd含量的增加，薄膜的透射率和禁带宽度降低，电导率增大。通过控制前驱体混合溶液中不同阳离子间的比例可以得到带宽可调的复合硫化物薄膜。

PREPARATION AND PROPERTIES OF (Zn,Cd)S FILMS BY SUCCESSIVE IONIC LAYER ADSORPTION AND REACTION

Successive ionic layer adsorption and reaction (SILAR) was applied to prepare zinc sulfide and (Zn,Cd)S thin films on glass substrates at room temperature using mixed ions precursor.Growth rates and surface morphologies of the films were characterized by environmental scan electron microscopy(ESEM) and X-ray photoelectron spectrometer(XPS). Optical and (electrical) properties of the films with different n(Zn)/n(Cd) were studied. The results show that the growth rate of the zinc sulfide films by SILAR is about 3 nm/cycle, which is higher than that of (Zn,Cd)S at the same precursor concentration. The thin films of (Zn,Cd)S are compact and homogenous by ESEM.The higher Cd content in films, compared with n(Zn)/n(Cd) in precursor solutions, is attributed to the lower solubility of CdS based on XPS.Transmittance and the band gap of the films decrease with the increase of the Cd content, while the conductivity is elevated. The band gap adjustable composite sulfide films can be obtained by controlling the ratio of mixed anions precursors.