An 8 × 160 Gb s⁻¹ all-silicon avalanche photodiode chip

In response to growing demands on data traffic, silicon (Si) photonics has emerged as a promising technology for ultra-high-speed and low-cost optical interconnects. However, achieving high-performance photodetectors with Si photonics requires integrating narrower-bandgap materials, resulting in more complex fabrication processes, higher costs and yield issues. To address this challenge, we demonstrate an all-Si receiver (RX) based on a cost-efficient, eight-channel, double-microring-resonator, avalanche photodiode. It has an aggregate data rate of 1.28 Tb s⁻¹. All channels show excellent uniformity in their device performance with a responsivity of 0.4 A W⁻¹, an ultra-low dark current of 1 nA, a high bandwidth of 40 GHz at −8 V and a \(k\) $k$ value of 0.28. To the best of our knowledge, this is the first demonstration of an all-Si RX supporting a record-high transmission data rate of 160 Gb s⁻¹ per channel, along with an ultra-low electrical crosstalk of less than −50 dB. This all-Si optical RX can compete with the commercial heterojunction-based RXs and promises ~40% chip cost saving, thus paving the way to realizing >3.2 Tb s⁻¹ interconnects for future optical networks.