Kim Sara, Lee Yong-Seok, Kim Nam-Hoon
Department of Electrical Engineering, Chosun University, Gwangju 61452, Republic of Korea.
Materials (Basel). 2023 Sep 6;16(18):6087. doi: 10.3390/ma16186087.
P-type Cu-Se thin films were deposited on glass substrates at room temperature using radio frequency magnetron sputtering by a single multi-component CuSe target. When using a multi-component target, the impact of the sputtering power on the homogeneity and stoichiometry within the thin films should be investigated in the depth direction to demonstrate a secondary effect on the electrical and optical properties of the thin films. Systematic characterization of the Cu-Se thin films, including the morphology, microstructure, chemical composition, and depth-directional chemical bonding state and defect structure of the thin films, revealed that the sputtering power played an important role in the homogeneity and stoichiometry of the thin films. At very low and very high sputtering power levels, the Cu-Se thin films exhibited more deviations from stoichiometry, while an optimized sputtering power resulted in more homogenous thin films with improved stoichiometry across the entire thin film thickness in the X-ray photoelectron spectroscopy depth profile, despite showing Se deficiency at all depths. A rapid decrease in carrier concentration, indicating a reduction in the net effect of total defects, was obtained at the optimized sputtering power with less deviation from stoichiometry in the Cu-Se thin films and the closest stoichiometric ratio at an intermediate depth.
采用射频磁控溅射法，通过单一的多组分CuSe靶材，在室温下于玻璃衬底上沉积P型Cu - Se薄膜。当使用多组分靶材时，应在深度方向上研究溅射功率对薄膜内均匀性和化学计量比的影响，以证明其对薄膜电学和光学性能的二次效应。对Cu - Se薄膜进行系统表征，包括薄膜的形貌、微观结构、化学成分以及深度方向的化学键合状态和缺陷结构，结果表明溅射功率对薄膜的均匀性和化学计量比起着重要作用。在非常低和非常高的溅射功率水平下，Cu - Se薄膜的化学计量比偏差更大，而优化的溅射功率则使薄膜在X射线光电子能谱深度剖析中在整个薄膜厚度范围内具有更均匀的化学计量比，尽管在所有深度都存在硒缺乏。在优化的溅射功率下，Cu - Se薄膜的化学计量比偏差较小且在中间深度处化学计量比最接近，此时载流子浓度迅速降低，表明总缺陷的净效应减小。
