Catalyst free Germanium (Ge) nanowires (NW) and thin film (TF) have been synthesized by employing GLAD technique inside an electron-beam evaporator. X-ray diffraction patterns confirmed the successful growth of polycrystalline Ge-NW and Ge-TF. The FEG-SEM image revealed the growth of highly oriented vertical nanowires with an average length of ∼110 nm and a diameter of ∼48 nm. The optical absorption of Ge-NW showed enhancement over the Ge-TF. The blue shift observed in optical absorption for the NW and TF samples is due to the quantum confinement. The work function is computed using Kelvin probe force microscopy (KPFM) for Ge-NW (∼4.11 eV) and Ge-TF (∼4.18 eV) samples. The current density for Ge-TF and Ge-NW, when exposed to light, is ∼0.85 mA/cm2 and ∼6.95 mA/cm2 at 5 V bias, respectively. Ag/Ge-NW/n-Si device exhibits maximum photosensitivity of 35 times compared to the Ge-TF device at −5.5 V. Additionally, better switching is observed for Ge-NW device compared to Ge-TF device, which is a good candidate for photodetector application.

中文翻译：

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使用开尔文探针力显微镜研究锗纳米线集成硅衬底的光电特性

通过在电子束蒸发器内采用 GLAD 技术合成了无催化剂的锗 (Ge) 纳米线 (NW) 和薄膜 (TF)。X 射线衍射图证实了多晶 Ge-NW 和 Ge-TF 的成功生长。FEG-SEM 图像显示了高度定向的垂直纳米线的生长，平均长度约为 110 nm，直径约为 48 nm。Ge-NW 的光吸收表现出优于 Ge-TF 的增强。在 NW 和 TF 样品的光吸收中观察到的蓝移是由于量子限制。使用开尔文探针力显微镜 (KPFM) 计算 Ge-NW (~4.11 eV) 和 Ge-TF (~4.18 eV) 样品的功函数。Ge-TF 和 Ge-NW 在光照下的电流密度在 5 V 偏压下分别为~0.85 mA/cm2 和~6.95 mA/cm2。