Germanium-tin on Silicon p-i-n photodiode with low dark current due to sidewall surface passivation

We demonstrate that the surface leakage current of a Ge 0.95 Sn 0.05 /Si p-i-n photodiode can be significantly reduced by -two orders by Si surface passivation. Furthermore, a dark current density of 0.073A/cm 2 (V bias = −1 V) is achieved.