Photodetection in hybrid single layer graphene/fully coherent Ge island nanostructures selectively grown on Si nano-tip patterns
发布时间：2025-04-30
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- 发布时间：
- 2025-04-30
- 论文名称：
- Photodetection in hybrid single layer graphene/fully coherent Ge island nanostructures selectively grown on Si nano-tip patterns
- 发表刊物：
- ACS Applied Materials & Interfaces
- 摘要：
- Dislocation networks are one of the most principle sources deteriorating the performances of devices based on lattice-mismatched heteroepitaxial systems. We demonstrate here a technique enabling fully coherent Ge islands selectively grown on nano-tip patterned Si (001) substrates. The Si-tip patterned substrate, fabricated by complementary metal-oxide-semiconductor (CMOS) compatible nanotechnology, features ~50 nm wide Si areas emerging from a SiO2 matrix and arranged in an ordered lattice. Molecular beam epitaxy (MBE) growths result in Ge nano-islands with high selectivity and having homogeneous shape and size. The ~850°C growth temperature required for ensuring selective growth has been shown to lead to the formation of Ge islands of high crystalline quality without extensive Si intermixing (with 91 at.% Ge). Nano-tip patterned wafers result in geometric, kinetic diffusion barrier intermixing hindrance confining the major intermixing to the pedestal region of Ge islands where kinetic diffusion barriers are however high. Theoretical calculations suggest that the thin SiGe layer at the interface plays a significant role in realizing our fully coherent Ge nano-islands free from extended defects especially dislocations. Single layer graphene (SLG)/Ge/Si-tip Schottky junctions were fabricated and thanks to the absence of extended defect in Ge islands, they demonstrate high performance photodetection characteristics with responsivity and Ion/Ioff ratio of ~45 mA/W and ~10(3), respectively.
- 合写作者：
- Gang Niu · Capellini Giovanni · Grzegorz Lupina · [...]
- 是否译文：
- 否
- 发表时间：
- 2016-01-01