Silicon photonics is widely used for near InfraRed (IR) applications up to 1.6 µm. It plays a key role in short-range optical data communications. However, silicon photonics does not really address mid-IR applications, particularly in the 1.6–5 µm wavelength range. This spectral region is essential for environmental/life sensing and safety applications relying on the optical features of molecular vibrations, the aim being to discern and categorize complex chemical entities. Growing markets for such analysis prioritise sensitivity, specificity, compactness, energy-efficient operation and cost effectiveness. The need for a CMOS-compatible integrated photonic platform for the mid-IR is obvious. Such fully-group-IV semiconductor platform should include low-loss guided interconnects, detectors, modulators and, critically, efficient integrated light sources. This paper provides a comprehensive review of recent advances in GeSn-based mid-IR silicon-compatible devices, including optically and electrically pumped lasers, light-emitting diodes and photodetectors. It also discusses the principles underlying these developments, with focuses on material growth techniques and processing methods.

中文翻译：

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用于 MIR 应用的 GeSn 合金的进展

硅光子学广泛用于高达 1.6 µm 的近红外 (IR) 应用。它在短距离光数据通信中发挥着关键作用。然而，硅光子学并不能真正解决中红外应用，特别是在 1.6–5 µm 波长范围内。该光谱区域对于依赖于分子振动的光学特征的环境/生命传感和安全应用至关重要，其目的是辨别和分类复杂的化学实体。此类分析的不断增长的市场优先考虑灵敏度、特异性、紧凑性、节能运行和成本效益。中红外对 CMOS 兼容集成光子平台的需求是显而易见的。这种全 IV 族半导体平台应包括低损耗引导互连、探测器、调制器，以及最重要的高效集成光源。本文全面回顾了基于 GeSn 的中红外硅兼容器件的最新进展，包括光学和电泵浦激光器、发光二极管和光电探测器。它还讨论了这些发展背后的原理，重点是材料生长技术和加工方法。