A comparative study of the optoelectronic properties of 250 μm and 60 μm InGaAs photodetectors

Abstract

The optoelectronic properties of 250 μm and 60 μm diameter mesa InGaAs-based photodetectors are compared through their I-V characteristics and responsivity. The 250 μm device exhibits a turn on voltage at 2 V, while the breakdown voltage is at 12 V. Its 60 μm counterpart has a turn on voltage of 1.2 V and a breakdown voltage of 4.8 V. The spectral responsivity at 9025 Å of the 250 μm device was found to be 0.32 A/W with the smaller device at 0.24 A/W. The differences in optoelectronic properties can be attributed differences in device fabrication, specifically in the metallization of the p and n contacts.