Near-infrared photoresponse of femtosecond-laser processed Se-doped silicon n^+ − n photodiodes

Abstract

-n photodiodes were fabricated from this material for the first time, to the best of our knowledge. The effects of the annealing temperature and the reverse bias voltage on the near-infrared responsivity were investigated. The photodiode exhibits optimal rectification and photoresponse at an annealing temperature of 500°C. At a 12 V bias, a responsivity of 2.41 A/W at 1064 nm is obtained. The linear increase at bias from 0 to 10 V and faster-than-linear increase at bias from 10 to 12 V for the responsivity are observed with the increase of the bias voltage. The results suggest that the gain mechanism is most likely to be a photoconductive gain.