Abstracts Thick epitaxial Ca2Si(100) films were first grown on Si(111) substrates by forming a sacrificial Mg2Si(111) template and converting it into the Ca2Si template. It was found that a temperature of 250 °C is sufficient to transfer it into the Ca2Si template with sufficient uniformity. During Ca and Si co-deposition at 250 °C, epitaxial Ca2Si(100) domains with two orientations are formed in a thin (100 nm) film, and increasing the substrate temperature to 300 °C leads to a deterioration in the Ca2Si crystalline quality due to a partial violation of its continuity and grain growth of the CaSi phase from Si substrate. An increase in the film thickness to 400 nm at 250 °C led to the appearance, in addition to the Ca2Si(100) epitaxial phase, of the second Ca2Si(010) epitaxial phase with both contributing to the LEED pattern. From the transmission and reflection spectra of the grown samples, it was found that Ca2Si film has a first direct interband transition at E1d = 1.095 ± 0.15 eV, strong defect adsorption lower 1.0 eV and dispersionless refractive index no ≤ 3.8. Eight Raman peaks and 6 FIR peaks were first registered and identified, which are in good agreement with theoretical calculations. The absorption coefficients characteristic of FIR peaks was determined, which can be used further in the quick estimation of the thickness of Ca2Si films through an intensity of FIR absorption peaks.

中文翻译：

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Si(111) 衬底上的 Ca2Si(100) 外延膜：模板生长、结构和光学特性

摘要 通过形成牺牲 Mg2Si(111) 模板并将其转化为 Ca2Si 模板，首先在 Si(111) 衬底上生长厚的外延 Ca2Si(100) 薄膜。发现 250 °C 的温度足以将其转移到具有足够均匀性的 Ca2Si 模板中。在 250 °C 的 Ca 和 Si 共沉积过程中，具有两个取向的外延 Ca2Si(100) 域在薄 (100 nm) 膜中形成，并且将衬底温度提高到 300 °C 会导致 Ca2Si 晶体质量下降由于部分违反其连续性和来自 Si 衬底的 CaSi 相的晶粒生长。在 250 °C 下将薄膜厚度增加到 400 nm，除了 Ca2Si(100) 外延相之外，还出现了第二个 Ca2Si(010) 外延相，两者都有助于 LEED 图案。从生长样品的透射和反射光谱发现，Ca2Si 膜在 E1d = 1.095 ± 0.15 eV 处具有第一直接带间跃迁，强缺陷吸附低于 1.0 eV，无色散折射率 no ≤ 3.8。首先登记和鉴定了8个拉曼峰和6个FIR峰，与理论计算吻合良好。确定了FIR峰的吸收系数特征，可进一步用于通过FIR吸收峰强度快速估计Ca2Si薄膜的厚度。首先登记和鉴定了8个拉曼峰和6个FIR峰，与理论计算吻合良好。确定了FIR峰的吸收系数特征，可进一步用于通过FIR吸收峰强度快速估计Ca2Si薄膜的厚度。首先登记和鉴定了8个拉曼峰和6个FIR峰，与理论计算吻合良好。确定了FIR峰的吸收系数特征，可进一步用于通过FIR吸收峰强度快速估计Ca2Si薄膜的厚度。