The effects of threading dislocations and tensile strain in Ge/Si photodetector

The paper aims to investigate the influences of the tensile strain and the threading dislocations (TDs) in the germanium (Ge) epitaxial layer on the performance of the Ge vertical p‐i‐n photodetectors on Si substrate.

The dark current, photo responsivity and time responsivity of detector were calculated using two‐dimensional drift‐diffusion device modeling and compared with experimental data.

The incorporation of the tensile strain and the reduction of the TDs in the Ge epilayer can increase the performance of the detector.

An optical design of detector is suggested with lower TD in the Ge buffer layer, which can exhibit superior performance.