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.