Epitaxy growth and characterization of InAs p-i-n photodetector through ion exchange for mid-infrared detection on Si substrates

We report an epitaxy growth and characterization of InAs photodetector (PD) on virtual Ge/Si and GaP/Si substrates. The effect of different types of the virtual substrate on the structure and performance of the InAs PD was studied. Although the lattice mismatch between InAs and Si is large (11.6%), close to 100% relaxation of InAs was achieved on both virtual substrates. A higher surface roughness was observed in the InAs layer grown GaP/Si as compared with that of Ge/Si. InAs PD with room temperature blackbody specific detectivity of ~5 × 108 cm·Hz1/2/W is achieved in photovoltaic mode on both types of virtual substrate.