We present here a combined experimental and theoretical study of the structural and chemical properties of polycrystalline Sn-Sb-Te film with nominal composition SnSb₂Te₄ grown by pulsed laser deposition technique on mylar substrate. From the experimental side, surface-sensitive techniques as x-ray photoelectron spectroscopy (XPS), grazing incidence x-ray diffractometry (GIXRD) and ^119mSn integral conversion electron Möβbauer spectroscopy (ICEMS) have been applied to the study of the film at room-temperature and under normal conditions of pressure. GIXRD showed that the Sn-Sb-Te film adopted a NaCl- type structure (Fm-3m), and in the detection limits, no other crystalline phase was revealed. ICEMS technique unambiguously indicated the coexistence of two different tin fractions: Sn(II), as expected for the SnSb₂Te₄ phase, and Sn(IV), suggesting oxidation of tin. Chemical in-depth profile obtained by means of XPS suggests the oxidation of all the constituent atoms at the topmost layers of the film and the progressive depletion of tin and antimony oxides going depth in the film. The in-depth atomic concentration profiles also reveals a notorious deficiency of Te in the sample. Theoretically, density functional theory-based calculations (assuming that the Sn-Sb-Te film adopts the Fm-3m structure) support the hypothesis that Te - vacancies sites are occupied by oxygen atoms during the natural oxidation process of Sn-Sb-Te film. Additionally, our calculations demonstrated that only the substitution of Te atoms by oxygen ones induces a semiconducting behavior of the otherwise metallic Sn-Sb-Te host.

我们在此展示了通过脉冲激光沉积技术在聚酯薄膜基板上生长的具有标称成分 SnSb ₂ Te ₄的多晶 Sn-Sb-Te 膜的结构和化学性质的组合实验和理论研究。在实验方面，表面敏感技术如 X 射线光电子能谱 (XPS)、掠入射 X 射线衍射 (GIXRD) 和^119mSn 积分转换电子莫β鲍尔光谱 (ICEMS) 已应用于室温和正常压力条件下的薄膜研究。GIXRD表明Sn-Sb-Te薄膜采用NaCl型结构（Fm-3m），在检测限内，没有发现其他晶相。ICEMS 技术明确表明两种不同的锡组分共存：Sn(II)，正如对 SnSb ₂ Te _{4 的}预期相和 Sn(IV)，表明锡被氧化。通过 XPS 获得的化学深度分布表明，薄膜最顶层的所有组成原子都被氧化，并且锡和锑氧化物在薄膜中逐渐耗尽。深入的原子浓度分布也揭示了样品中 Te 的严重缺陷。理论上，基于密度泛函理论的计算（假设 Sn-Sb-Te 薄膜采用 Fm-3m 结构）支持在 Sn-Sb-Te 薄膜的自然氧化过程中 Te - 空位被氧原子占据的假设. 此外，我们的计算表明，只有将 Te 原子替换为氧原子才能诱导其他金属 Sn-Sb-Te 主体的半导体行为。