Ultra-broadband THz field detection by ion-implanted III-VPC antenna

Abstract

The photoconductive (PC) antenna fabricated on arsenic-ion-implanted GaAs (GaAs:As+) and proton-bombarded InP (InP:H+) substrates are shown to have a useful detection bandwidths beyond 30 THz. This is comparable to that of the reference LT-GaAs PC antenna. The signal-to-noise ratio of these ion-implanted III-V PC antennas are, however, worse than that of the LT-GaAs devices because of the higher stray currents of the former under illumination. Ion-implanted III-V PC antennas are nevertheless attractive because the implanters are widely available, process parameters well-established and compatible with the IC industry. Implantations in selective areas are also straight forward. Our results suggest that ion-implanted III-V material can be a good choice as substrate or THz PC antennas, if the resistivity is increased by a proper annealing process and/or optimizing the implantation recipe.