High speed InGaAs photodetector modules for fibre optic communications

InGaAsP/InGaAs photodetector modules with low dark current, high speed and responsivity in the 1300-1550 nm wavelength region are presented The photodetector modules were fabricated as a planar p-i-n photodiode chips placed in a fibre optic matching receptacles. The studies of optical characteristics of the modules have shown that the most promising decision is to use the optical matching medium to achieve the back reflection attenuation more than 60 dB. The responsivity of the photodetector module increases up to 10 percent if compared with one of commonly used p-i-n photodiode and equals 0.95±0.05 A/W at 1345 nm. The study of dark current characteristics at 22°C and 5 V bias has shown that the 30 μm and 100 μm diameter photodiodes have the current values of (0.1-0.2)·10^-9 A and (1.0-2.0)·10^-9 A, respectively. The devices with matching 50 Ω resistors have -3 dB bandwidth over 1.5-2.0 GHz