High photoresponsivity germanium nanodot PhotoMOSFETs for monolithically-integrated Si optical interconnects

We presented a self-organized, MOS gate-stacking structure of SiO
₂
/Ge-dot/SiO
₂
/Si
_1-x
Ge
_x
-shell, using thermal oxidation of poly-Si
_0.85
Ge
_0.15
nanopillars over buffer Si
₃
N
₄
on the Si substrate, for the fabrication of high performance Ge-dot photo MOSFETs. Low dark current of 3 μA/μm
²
, Superior high photo responsivity of 1400-710A/W, and short response time of <;0.8ns are measured on 90nm Ge-dot photo MOSFETs with W/L = 70μm/3μm under 850nm-1550nm illumination, providing a practically-achievable, core building block for monolithically-integrated Si optical interconnects.