Highly sensitive 10 Gb/s PAM‐4 optical receiver circuit for three‐dimensional optoelectronic integration

This study presents a 0.35 µm silicon germanium bipolar complementary metal‐oxide‐semiconductor 10 Gb/s receiver circuit optimised for photonic–electronic three‐dimensional integration. Measurements were conducted on a test‐chip with a voltage‐input signal, which was converted to a current via a series resistor. On the basis of measurement results and using the expected value of the photodetector responsivity of 1 A/W, the PAM‐4 circuit consumes 145 mW, sensitivity is −21.8 dBm at 10 Gb/s, and at a bit error rate = 10 −9 .