Abstract In this review article, we address key material parameters as well as the fabrication and application of crystalline GeSn binary and SiGeSn ternary alloys. Here, the transition from an indirect to a fundamental direct bandgap material will be discussed. The main emphasis, however, is put on the Si–Ge–Sn epitaxy. The low solid solubility of α-Sn in Ge and Si of below 1 at.% along with the large lattice mismatch between α-Sn (6.489 A) and Ge (5.646 A) or Si (5.431 A) of about 15% and 20%, respectively, requires non-equilibrium growth processes. The most commonly used approaches, i.e. molecular beam epitaxy (MBE) and chemical vapor deposition (CVD), will be reviewed in terms of crucial process parameters, structural as well as optical quality and employed precursor combinations including Germanium hydrides, Silicon hydrides and a variety of Sn compounds like SnD4, SnCl4 or C6H5SnD3. Special attention is devoted to the growth temperature window and growth rates being the most important growth parameters concerning the substitutional incorporation of Sn atoms into the Ge diamond lattice. Furthermore, the mainly CVD-driven epitaxy of high quality SiGeSn ternary alloys, allowing the decoupling of band engineering and lattice constant, is presented. Since achieving fundamental direct bandgap Sn-based materials strongly depends on the applied strain within the epilayers, ways to control and modify the strain are shown, especially the plastic strain relaxation of (Si)GeSn layers grown on Ge. Based on recently achieved improvements of the crystalline quality, novel low power and high mobility GeSn electronic and photonic devices have been developed and are reviewed in this paper. The use of GeSn as optically active gain or channel material with its lower and potentially direct bandgap compared to fundamentally indirect Ge (0.66 eV) and Si (1.12 eV) provides a viable solution to overcome the obstacles in both fields photonics and electronics. Moreover, the epitaxial growth of Sn-based semiconductors using CMOS compatible substrates on the road toward a monolithically integrated and efficient group IV light emitter is presented.

中文翻译：

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Si-Ge-Sn 合金：从生长到应用

摘要 在这篇评论文章中，我们讨论了关键材料参数以及晶体 GeSn 二元和 SiGeSn 三元合金的制造和应用。在这里，将讨论从间接带隙材料到基本直接带隙材料的转变。然而，主要重点放在 Si-Ge-Sn 外延上。α-Sn 在 Ge 和 Si 中的低固溶度低于 1 at.%，以及 α-Sn (6.489 A) 和 Ge (5.646 A) 或 Si (5.431 A) 之间约 15% 和 20 的大晶格失配%，分别需要非平衡增长过程。最常用的方法，即分子束外延 (MBE) 和化学气相沉积 (CVD)，将根据关键工艺参数、结构和光学质量以及采用的前体组合（包括氢化锗、硅氢化物和各种 Sn 化合物，如 SnD4、SnCl4 或 C6H5SnD3。特别注意生长温度窗口和生长速率是与 Sn 原子置换结合到 Ge 金刚石晶格中的最重要的生长参数。此外，还介绍了高质量 SiGeSn 三元合金的主要 CVD 驱动外延，允许带工程和晶格常数的解耦。由于实现基本的直接带隙 Sn 基材料在很大程度上取决于外延层内施加的应变，因此显示了控制和修改应变的方法，特别是在 Ge 上生长的 (Si)GeSn 层的塑性应变弛豫。基于最近实现的结晶质量改进，新型低功率和高迁移率的 GeSn 电子和光子器件已经开发出来，并在本文中进行了综述。与基本间接的 Ge (0.66 eV) 和 Si (1.12 eV) 相比，使用 GeSn 作为光学有源增益或通道材料，具有较低且潜在的直接带隙，为克服光子学和电子学领域的障碍提供了可行的解决方案。此外，介绍了在通往单片集成和高效 IV 族光发射器的道路上，使用 CMOS 兼容衬底的 Sn 基半导体的外延生长。12 eV) 为克服光子学和电子学领域的障碍提供了可行的解决方案。此外，介绍了在通往单片集成和高效 IV 族光发射器的道路上，使用 CMOS 兼容衬底的 Sn 基半导体的外延生长。12 eV) 为克服光子学和电子学领域的障碍提供了可行的解决方案。此外，介绍了在通往单片集成和高效 IV 族光发射器的道路上，使用 CMOS 兼容衬底的 Sn 基半导体的外延生长。