We discuss the design and demonstration of various III–V/Si asymmetric Mach–Zehnder interferometer (AMZI) and ring-assisted AMZI (de-)interleavers operating at O-band wavelengths with 65 GHz channel spacing. The wafer-bonded III–V/Si metal-oxide-semiconductor capacitor (MOSCAP) structure facilitates ultra-low-power phase tuning on a heterogeneous platform that allows for complete monolithic transceiver photonic integration. The second- and third-order MOSCAP AMZI (de-)interleavers exhibit cross-talk (XT) levels down to -22 dB and -32dB with tuning powers of 83.0 nW and 53.0 nW, respectively. The one-, two-, and three-ring-assisted MOSCAP AMZI (de-)interleavers have XT levels down to -27 dB, -22 dB, and -20dB for tuning powers of 10.0 nW, 7220.0 nW, and 33.6 nW, respectively. The leakage current density is measured to be in the range of 1.6–27μA/cm2. To the best of our knowledge, we have demonstrated for the first time, athermal III–V/Si MOSCAP (de-)interleavers with the lowest XT and reconfiguration power consumption on a silicon platform.

In many application scenarios, silicon (Si) photonics favors the integration of III-V gain material onto Si substrate to realize the on-chip light source. In addition to the current popular integration approaches of III-V-on-Si wafer bonding or direct heteroepitaxial growth, a newly emerged promising solution of epitaxial regrowth on bonded substrate has attracted a lot of interests. High-quality III-V material realization and successful laser demonstrations show its great potential to be a promising integration platform for low-cost, high-integration density and highly scalable active-passive photonic integration on Si. This paper reviews recent research work on this regrowth on bonded template platform including template developments, regrown material characterizations and laser demonstrations. The potential advantages, opportunities and challenges of this approach are discussed.