Separated-transport-recombination p-i-n photodiode for high-speed and high-power performance

We demonstrate a novel p-i-n photodiode (PD) structure, the separated-transport-recombination PD, which can greatly relieve the tradeoffs among the resistance-capacitance bandwidth limitation, responsivity, and output saturation power performance. Incorporating a short carrier lifetime (less than 1 ps) epitaxial layer to serve as a recombination center, this device exhibits superior speed and power performance to a control PD that has a pure intrinsic photoabsorption layer. Our demonstrated structure can also eliminate the bandwidth degradation problem of the high-speed photodetector, whose active photoabsorption layer is fully composed of short lifetime (∼1 ps) materials, under high dc bias voltages.