Abstract
In this letter, the authors introduce a GaAs/AlGaAs based unitraveling carrier photodiode (UTC-PD) for a wavelength of around 830 nm. There is significant bias- and output-current-dependent bandwidth enhancement phenomena observed with this device. According to their microwave and optical-to- electrical measurement results, such distinct phenomena can occur under a much lower current density (0.3 mA/μm 2 vs 0.05 mA/μm 2 ) than previously reported for InP-InGaAs UTC-PDs. This can be attributed to the self-induced field in the absorption region, made possible due to the optimized p-type doping profile. © 2006 American Institute of Physics.