DILUTED-ABSORPTION AND DISTRIBUTED-ABSORPTION MICROWAVE WAVE-GUIDE PHOTODIODES FOR HIGH-EFFICIENCY AND HIGH-POWER

We propose a new microwave photodetector with high responsivity, which can handle both high optical power and deliver high microwave-output power, The distributed-absorption waveguide photodiode (DWGPD) is spec ially designed to equally distribute the photocarriers over the maximu m surface area available in order to reduce the nonlinearities of elec trical response due to electric-field screening effects, The expected calculated performances of this DWGPD is compared to other types of br oad-band photodetectors in terms of linear microwave-output power, qua ntum efficiency, and thermal behavior, The fabricated DWGPD's have a r esponsivity of 1 A/W, cutoff frequency of 29 GHz, and linear response up to 8 mA limited in this experiment by contacting electrodes.