Thermal evaporation is a simple and rapid process to fabricate BaSi${}_2$ films for solar cell applications. In this study, we investigated the extent of Ba diffusion into the Si substrate and SiO evaporation, which occur during the BaSi${}_2$ film formation, aiming at elucidating BaSi${}_2$ film formation processes. Composition depth profiles determined by Auger electron spectroscopy reveal that SiO evaporates at 650 ${}^{°}$C and above concurrently with surface oxidation, which is supported by surface roughening observed by secondary electron microscopy. Ba diffusion into the substrate is also detected from composition depth profiles. It is demonstrated that the amount of Ba in-diffusion decreases as the deposition rate increases. The present findings serve for controlling the composition of BaSi${}_2$ evaporated films.

中文翻译：

---

热蒸发在Si衬底上形成BaSi2薄膜过程中Ba扩散和SiO蒸发的研究

热蒸发是制造 BaSi 的一种简单而快速的工艺${}_2$用于太阳能电池应用的薄膜。在这项研究中，我们研究了 BaSi 扩散过程中发生的 Ba 扩散到 Si 衬底和 SiO 蒸发的程度。${}_2$ 成膜，旨在阐明BaSi${}_2$成膜过程。俄歇电子能谱确定的成分深度分布表明 SiO 在 650 ${}^{°}$C 及以上同时发生表面氧化，这是由二次电子显微镜观察到的表面粗糙化支持的。还可以从成分深度分布中检测到 Ba 扩散到基材中。结果表明，随着沉积速率的增加，Ba 的扩散量减少。本研究结果用于控制 BaSi 的组成${}_2$ 蒸发的薄膜。