The short-wave infrared (SWIR) wavelength, especially 1.55 μm, has attracted significant attention in various areas such as high-speed optical communication and LiDAR systems. Avalanche photodiodes (APDs) are a critical component as a receiver in these systems due to their internal gain, which enhances the system performance. Silicon-based APDs are promising since they are CMOS compatible, but they are limited in detecting 1.55 μm light detection. This study proposes a p-type Si on n-type GaAs0.51Sb0.49 (GaAsSb) lattice matched to InP substrates heterojunction formed using a grafting technique for future GaAsSb/Si APD technology. A p+Si nanomembrane is transferred onto the GaAsSb/AlInAs/InP substrate, with an ultrathin ALD-Al2O3 oxide at the interface, which behaves as both double-side passivation and quantum tunneling layers. The devices exhibit excellent surface morphology and interface quality, confirmed by atomic force microscope and transmission electron microscope. Also, the current–voltage (I–V) of the p+Si/n−GaAsSb heterojunction shows the rectifying characteristics with an ideality factor of 1.8. The I–V tests across multiple devices confirm high consistency and yield. Furthermore, the x-ray photoelectron spectroscopy measurement reveals that GaAsSb and Si are found to have type-II band alignment with a conduction band offset of 50 meV, which is favorable for the high-bandwidth APD application. The demonstration of the GaAsSb/Si heterojunction highlights the potential to advance current SWIR PD technologies.

中文翻译：

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接枝 Si/GaAsSb 异质结的结构和电学特性


短波红外 （SWIR） 波长，尤其是 1.55 μm，在高速光通信和 LiDAR 系统等各个领域引起了极大的关注。雪崩光电二极管 （APD） 是这些系统中作为接收器的关键组件，因为它们具有内部增益，可增强系统性能。硅基 APD 很有前途，因为它们与 CMOS 兼容，但它们在检测 1.55 μm 光检测方面受到限制。本研究提出了一种 n 型 GaAs0.51Sb0.49 （GaAsSb） 晶格上的 p 型硅，该晶格与使用接枝技术形成的 InP 衬底异质结相匹配，用于未来的 GaAsSb/Si APD 技术。p+Si 纳米膜被转移到 GaAsSb/AlInAs/InP 衬底上，界面处有超薄的 ALD-Al2O3 氧化物，其作用类似于双面钝化和量子隧穿层。这些器件表现出优异的表面形貌和界面质量，经原子力显微镜和透射电子显微镜证实。此外，p+Si/n-GaAsSb 异质结的电流-电压 （I-V） 显示出理想因子为 1.8 的整流特性。跨多个器件的 I-V 测试证实了高一致性和产量。此外，X 射线光电子能谱测量表明，GaAsSb 和 Si 具有 II 型能带对准，导带偏移为 50 meV，这有利于高带宽 APD 应用。GaAsSb/Si 异质结的演示凸显了推动当前 SWIR PD 技术的潜力。