Abstract Inexpensive and stable solar cells based on oxide materials are currently strongly investigated. The surest candidates are copper oxides, which unlike to other metal oxides display strong absorption across the visible range. Although, copper oxides thin film can be deposited by the number of methods, cost effective techniques applicable for large scale production are necessary. Therefore, the main focus of this paper was turned to the simple and time effective thermal oxidation of copper sheets using relatively low temperatures 200–400 °C. The surface pretreatment was selected in order to support homogeneous growth conditions. The basic material research presented here included the morphological, compositional and microstructural aspects of grown copper oxides. The surface roughness of manufactured layers for investigated temperature range was described either by AFM microscopy where Ra was assessed between 8.9 and 67.6 nm and also by the optical method where calculated haze factor ranged from 34 to 79.3%. Microstructure and phase composition studies were performed by means of TEM and XRD supplemented by XPS surface analysis confirming the dominating phase of copper (I) oxide capped with thin surface CuO layer. Finally, the optical properties were described allowing to determine the sample absorptivity and band gap energy varying in the range 2.43–1.93 eV.

中文翻译：

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铜片低温氧化得到氧化铜的材料研究

摘要 目前，人们正在大力研究基于氧化物材料的廉价且稳定的太阳能电池。最有把握的候选物是氧化铜，与其他金属氧化物不同，它在可见光范围内具有强吸收性。尽管可以通过多种方法沉积氧化铜薄膜，但需要适用于大规模生产的成本效益高的技术。因此，本文的主要焦点转向使用相对较低的温度 200–400 °C 对铜板进行简单且时间有效的热氧化。选择表面预处理以支持均匀的生长条件。这里介绍的基础材料研究包括生长的氧化铜的形态、成分和微观结构方面。在所研究的温度范围内，制造层的表面粗糙度通过 AFM 显微镜描述，其中 Ra 评估在 8.9 和 67.6 nm 之间，也通过光学方法描述，其中计算的雾度因子范围为 34 到 79.3%。微观结构和相组成研究通过 TEM 和 XRD 进行，辅以 XPS 表面分析，证实了覆盖有薄表面 CuO 层的氧化铜 (I) 的主要相。最后，描述了光学特性，允许确定在 2.43-1.93 eV 范围内变化的样品吸收率和带隙能量。微观结构和相组成研究通过 TEM 和 XRD 进行，辅以 XPS 表面分析，证实了覆盖有薄表面 CuO 层的氧化铜 (I) 的主要相。最后，描述了光学特性，允许确定在 2.43-1.93 eV 范围内变化的样品吸收率和带隙能量。微观结构和相组成研究通过 TEM 和 XRD 进行，辅以 XPS 表面分析，证实了覆盖有薄表面 CuO 层的氧化铜 (I) 的主要相。最后，描述了光学特性，允许确定在 2.43-1.93 eV 范围内变化的样品吸收率和带隙能量。