avalanche photodiodes, lateral structure, electric field confinement, high gain
A novel lateral Ge/Si avalanche photodiode without a charge region is investigated herein using device physical simulation. High field is provided by the band-gap barrier and build-in field at the Ge/Si interface in the vertical direction. Modulating the Si mesa thickness (0-0.4μm) and impurity concentration of the intrinsic Si substrate (1×1016-4×1016cm-3) strengthens the electric field confinement in the substrate region and provides a high avalanche multiplication in the Si region. When the Si mesa thickness is 0.3μm, and the impurity concentration of the Si substrate is 2×1016cm-3, the Lateral Avalanche PhotoDiode (LAPD) exhibits a peak gain of 246 under 1.55μm incident light power of -22.2dBm, which increases with decreasing light intensity.
Tsinghua University Press
Wenzhou Wu, Zhi Liu, Jun Zheng et al. Interface Electric Field Confinement Effect of High-Sensitivity Lateral Ge/Si Avalanche Photodiodes. Tsinghua Science and Technology 2019, 24(1): 1-8.