Sub-volt high-speed silicon MOSCAP microring modulator driven by high-mobility conductive oxide

Abstract Silicon microring modulator plays a critical role in energy-efficient optical interconnect and optical computing owing to its ultra-compact footprint and capability for on-chip wavelength-division multiplexing. However, existing silicon microring modulators usually require more than 2 V of...

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Bibliographic Details
Main Authors: Wei-Che Hsu, Nabila Nujhat, Benjamin Kupp, John F. Conley, Haisheng Rong, Ranjeet Kumar, Alan X. Wang
Format: Article
Language:English
Published: Nature Portfolio 2024-01-01
Series:Nature Communications
Online Access:https://doi.org/10.1038/s41467-024-45130-4
Description
Summary:Abstract Silicon microring modulator plays a critical role in energy-efficient optical interconnect and optical computing owing to its ultra-compact footprint and capability for on-chip wavelength-division multiplexing. However, existing silicon microring modulators usually require more than 2 V of driving voltage (Vpp), which is limited by both material properties and device structures. Here, we present a metal-oxide-semiconductor capacitor microring modulator through heterogeneous integration between silicon photonics and titanium-doped indium oxide, which is a high-mobility transparent conductive oxide (TCO) with a strong plasma dispersion effect. The device is co-fabricated by Intel’s photonics fab and our in-house TCO patterning processes, which exhibits a high modulation efficiency of 117 pm/V and consequently can be driven by a very low Vpp of 0.8 V. At a 11 GHz modulation bandwidth where the modulator is limited by the RC bandwidth, we obtained 25 Gb/s clear eye diagrams with energy efficiency of 53 fJ/bit.
ISSN:2041-1723