Ge on Si p-i-n photodiodes for a bit rate of up to 25 Gbit/s

Ge on Si p-i-n photodiodes are characterized on wafer in the time domain at a wavelength of 1550 nm. The photodiode output signal is sampled by a flip flop. At a bit rate of 25 Gbit/s and a Pseudo Random Bit Sequence (PRBS) length of 2
⁷
-1, the Bit Error Ratio (BER) is smaller than 10
⁻¹²
.