A 3D Integrated Energy-Efficient Transceiver Realized by Direct Bond Interconnect of Co-Designed 12 nm FinFET and Silicon Photonic Integrated Circuits

This article presents the first experimental demonstration of an energy-efficient electronic-photonic co-designed transceiver circuit heterogeneously 3D co-integrated with high-density, low-parasitic Direct Bond Interconnect (DBI) featuring 32-channel microdisk modulator/filter based optical transceivers for Wavelength Division Multiplexing (WDM) scheme. The silicon photonic chip is fabricated in AIM Photonics' integrated photonic technology, and the optical transceiver chip is fabricated in GlobalFoundries 12 nm FinFET process. The optical transmitter consumes 2.823 mW at 18 Gb/s, with 1.2 V-ppd electrical modulation differential swing, and achieves an extinction ratio of 7 dB. The optical receiver utilized quarter-rate sampling via Injection-Locked Oscillator (ILO) and forward clocking architecture, consumes 6.11 mW, and achieves the Optical Modulation Amplitude (OMA) sensitivity of -20.3 dBm at 12 Gb/s under the photodiode responsivity of 0.8 A/W. The receiver can further operate at 25 Gb/s with a sensitivity of -17.01 dBm and 191 fJ/bit. The transceiver pair at 18 Gb/s achieves 496 fJ/bit link efficiency.