Journal article

Vertical Ge-Si Nanowires with Suspended Graphene Top Contacts as Dynamically Tunable Multispectral Photodetectors

Shi Qiang Li, Amit Solanki, Jacopo Frigerio, Daniel Chrastina, Giovanni Isella, Changxi Zheng, Arman Ahnood, Kumaravelu Ganesan, Kenneth B Crozier



Numerous applications would be enabled by pixels for multispectral imaging whose spectral responses can be dynamically tuned and that can be potentially manufactured at low cost. Here, we show such a capability, by experimentally demonstrating arrays of vertically oriented germanium–silicon heterojunction nanowires with graphene top contacts. Our devices present opportunities for multispectral imaging because their responsivity spectra can be tailored by choice of nanowire radius for enhanced absorption at certain wavelengths across the visible to short-wave infrared. Importantly, these responsivity spectra can also be dynamically tuned by bias voltage. We demonstrate this experimentally by ..

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Awarded by Australian Research Council

Funding Acknowledgements

This work was supported by the Australian Research Council (DP150103736, DP180104141, and FT140100577) and by VESKI. Electron microscopy was performed at the Bio21 Advanced Microscopy Facility, the University of Melbourne. Fabrication was performed in part at the Melbourne Centre for Nanofabrication (MCN) in the Victorian Node of the Australian National Fabrication Facility (ANFF).