Thin films of copper oxide were prepared through two steps: the formation of metallic copper thin films by DC sputtering technique and oxidizing the metallic copper films through microwave plasma chemical vapor deposition technique. X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) were used to detect the crystalline phases and the films morphology, respectively. Tenorite CuO phase with interlocking between grains were observed and detected. Optical and photoluminescence properties were investigated by UV–Vis-NIR to detect the optical transparency, optical band gap, and refractive index of the prepared films. The optical transmittance of the studied films was resolved by Swanepoel’s procedure due to the presence of the optical interference in such samples. The optical band gap values were observed to decrease from 2.355 to 1.986 eV as the microwave power increase. A strong UV emission at around 358 nm was observed in all CuO samples. Moreover, weak blue and green emission were also observed in the photoluminescence spectra.

中文翻译：

---

不同微波功率下纳米晶CuO薄膜的结构、光学和光致发光研究

氧化铜薄膜的制备分两步：通过直流溅射技术形成金属铜薄膜和通过微波等离子体化学气相沉积技术氧​​化金属铜薄膜。X射线衍射（XRD）和场发射扫描电子显微镜（FESEM）分别用于检测晶相和薄膜形貌。观察并检测到晶粒间具有互锁的 Tenorite CuO 相。通过 UV-Vis-NIR 研究光学和光致发光特性，以检测制备的薄膜的光学透明度、光学带隙和折射率。由于此类样品中存在光学干涉，所研究薄膜的光学透射率由 Swanepoel 程序解决。观察到光学带隙值从 2 减小。随着微波功率的增加，355 到 1.986 eV。在所有 CuO 样品中都观察到 358 nm 附近的强紫外线发射。此外，在光致发光光谱中也观察到微弱的蓝色和绿色发射。