Abstract We applied magnesiothermic reduction to silica glass substrates at various conditions including solid state or solid-Mg liquid reaction, and solid-Mg vapor reaction. Magnesium silicide with highly oriented to the 〈110〉 direction against the substrate surface was obtained in the solid state reaction at temperatures from 600 °C to 700 °C using Mg grains while Si crystallites were obtained in the reaction with Mg film deposited on the glass substrate at 560 °C. On the other hand, in the reduction with Mg vapor at 575 °C, brown and amorphous layer was formed on the surface of the silica glass substrate. The layer was transparent in the visible and near-infrared regions, and showed an interference pattern in the transmission spectra, indicating the homogeneity of the layer. The thickness and refractive index were estimated as 770 nm and 1.94, respectively. As the reaction with Mg vapor proceeded further, Mg2Si and MgO crystallites were formed. Oxidation states and their depth profiles of silicon atoms in the layers were investigated by X-ray photoelectron spectroscopy. The silicon atoms in the brown and amorphous layer existed in intermediate oxidation states, −2 and +3. The reaction proceeding, the formal charge of the silicon atoms varied to −4 corresponding to Mg2Si and +2.

中文翻译：

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二氧化硅玻璃基板的镁热还原—生成层中硅的化学状态

摘要 我们在各种条件下对石英玻璃基板进行了镁热还原，包括固态或固-镁液相反应，以及固-镁气相反应。在 600 °C 到 700 °C 的温度下，使用 Mg 晶粒在固态反应中获得了相对于衬底表面的 <110> 方向高度取向的硅化镁，而在与沉积在玻璃上的 Mg 膜的反应中获得了 Si 微晶基板在 560 °C。另一方面，在 575 °C 下用 Mg 蒸气还原，在石英玻璃基板表面形成棕色和非晶层。该层在可见光和近红外区域是透明的，并且在透射光谱中显示出干涉图案，表明该层的均匀性。厚度和折射率估计为 770 nm 和 1.94，分别。随着与Mg蒸气的反应进一步进行，形成Mg2Si和MgO微晶。通过X射线光电子能谱研究了层中硅原子的氧化态及其深度分布。棕色和非晶层中的硅原子以中间氧化态 -2 和 +3 存在。反应进行时，硅原子的形式电荷变化为-4，对应于Mg2Si和+2。