A 15-Gb/s 2.4-V Optical Receiver Using a Ge-on-SOI Photodiode and a CMOS IC

We report the fastest (15 Gb/s) and lowest voltage (2.4V) all-silicon-based optical receiver to date. The receiver consists of a lateral, interdigitated, germanium-on-silicon-on-insulator (Ge-on-SOI) photodiode wire-bonded to a 0.13-mum complementary metal-oxide-semiconductor (CMOS) receiver integrated circuit (IC). The photodiode has an external quantum efficiency of 52% at lambda=850 nm and a dark current of 10 nA at -2 V. The small-signal transimpedance of the receiver is 91-dBOmega and the bandwidth is 6.6 GHz. At a bit-error rate of 10^-12 and lambda=850 nm; the receiver exhibits sensitivities of -11.0, -9.6, and -7.4 dBm at 12.5, 14, and 15 Gb/s, respectively. The receiver operates error-free at rates up to 10 Gb/s with an IC supply voltage as low as 1.5 V and with a photodiode bias as low as 0.5 V. The power consumption is 3 to 7 mW/Gb/s. The Ge-on-SOI photodiode is well suited for integration with CMOS processing, raising the possibility of producing high-performance, low-voltage, monolithically integrated receivers based on this technology in the future