Toward understanding and optimizing Au-hyperdoped Si infrared photodetectors

Au-hyperdoped Si absorbs near-infrared (NIR) light and recent efforts have successfully produced Si-based NIR photodetectors based on this property but with low detection efficiencies. Here, we investigate the differences between the optical and photocurrent properties of Auhyperdoped Si. Although defects introduced during fabrication of these materials may not exhibit significant optical absorption, we show that they can produce a measurable photocurrent under NIR illumination. Our results indicate that the optimal efficiency of impurity-hyperdoped Si materials is yet to be achieved and we discuss these opportunities in light of our results. This work thus represents a step forward in demonstrating the viability of using impurity-hyperdoped Si materials for NIR photodetection.The authors acknowledge the US Army (Contract No. FA5209-16-P-0104) and the Australian Nanotechnology Network travel grant for financial support on this project. B.C.J. and C.T.-K.L. acknowledge the Australian Research Council Center of Excellence for Quantum Computation and Communication Technology (Grant No. CE170100012)