Sun Xiaolin, Zhang Ting, Yu Linwei, Xu Ling, Wang Junzhuan
National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
Institute of Electronics Information Engineering, Sanjiang University, Nanjing, 210012, China.
Sci Rep. 2019 Dec 24;9(1):19752. doi: 10.1038/s41598-019-56374-2.
In this work, three-dimensional (3D) radial heterojunction photodetectors (PD) were constructed over vertical crystalline Si nanowires (SiNWs), with stacked hydrogenated amorphous germanium (a-Ge:H)/a-Si:H thin film layer as absorbers. The hetero absorber layer is designed to benefit from the type-II band alignment at the a-Ge/a-Si hetero-interface, which could help to enable an automated photo-carrier separation without exterior power supply. By inserting a carefully controlled a-Si passivation layer between the a-Ge:H layer and the p-type SiNWs, we demonstrate first a convenient fabrication of a new hetero a-Ge/a-Si structure operating as self-powered photodetectors (PD) in the near-infrared (NIR) range up to 900 nm, indicating a potential to serve as low cost, flexible and high performance radial junction sensing units for NIR imaging and PD applications.
在这项工作中，在垂直的晶体硅纳米线（SiNWs）上构建了三维（3D）径向异质结光电探测器（PD），采用堆叠的氢化非晶锗（a-Ge:H）/非晶硅（a-Si:H）薄膜层作为吸收体。异质吸收层的设计得益于a-Ge/a-Si异质界面处的II型能带排列，这有助于在无需外部电源的情况下实现自动光生载流子分离。通过在a-Ge:H层和p型SiNWs之间插入精心控制的非晶硅钝化层，我们首次展示了一种便捷的新异质a-Ge/a-Si结构的制造方法，该结构在高达900nm的近红外（NIR）范围内用作自供电光电探测器（PD），表明其有潜力作为低成本、柔性且高性能的径向结传感单元用于近红外成像和光电探测器应用。
