Physics / mechanism
Silicon photonics integrates optical components—waveguides, modulators, photodetectors, multiplexers—onto silicon substrates using CMOS-compatible fab processes (typically 45 nm SOI or 300 mm wafers at GlobalFoundries, Intel, TSMC). Light is confined via total internal reflection in Si/SiO₂ waveguides (Δn ≈ 2). Key bottleneck: silicon’s indirect bandgap forces hybrid III-V integration (InP, GaAs) or Ge for efficient lasing and detection. State-of-art transceivers hit 400 Gbps–1.6 Tbps per module; insertion loss <1 dB/cm waveguide propagation; modulator bandwidth >50 GHz (carrier-depletion Mach-Zehnder or ring resonator). Leading fabs: GlobalFoundries 45SPCLO, Intel Foundry, IMEC.
Competitive landscape
InP photonic integrated circuits offer superior gain and native laser integration but are expensive, small-wafer (4”), and not CMOS-compatible. Lithium niobate on insulator (LNOI) delivers best-in-class modulator performance (Vπ <1 V, bandwidth >100 GHz) but lacks integration density. Polymer photonics suits low-cost sensing. Silicon nitride (Si₃N₄) fills low-loss, visible-wavelength, and nonlinear niches.
Companies using
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Frontier (open questions)
- To be added.