PN diode optical modulators fabricated in rib waveguides
AssigneeLuxtera, Inc.
InventorsLawrence C. Gunn, III, Roger Koumans, Bing Li, Guo Liang Li, Thierry J. Pinguet
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Abstract
High speed optical modulators can be made of a reverse biased lateral PN diode formed in a silicon rib optical waveguide disposed on a SOI or other silicon based substrate. A PN junction is formed at the boundary of the P and N doped regions. The depletion region at the PN junction overlaps with the center of a guided optical mode propagating through the waveguide. Electrically modulating a reverse biased lateral PN diode causes a phase shift in an optical wave propagating through the waveguide. Prior art forward biased PN and PIN diode modulators have been relatively low speed devices.
Claims18
An optoelectronic device on a substrate comprising a rib waveguide and a lateral PN diode,
- where the rib waveguide comprises:
- a slab of monocrystalline silicon formed on the substrate, and
- a rib formed on the slab of monocrystalline silicon;
- the lateral PN diode comprises:
- first and second doped regions formed in the slab of monocrystalline silicon, where the second doped region is oppositely charged to the first doped region and first and second electrical contacts formed in the respective first and second doped regions in the slab of monocrystalline silicon,
- where a PN junction is formed at the boundary of the first and second doped regions, a depletion region at the PN junction is substantially in the center of a guided optical mode propagating through the rib waveguide;
- and,
- wherein a circuit is coupled to the first and second electrical contacts of the PN diode wherein the circuit comprises a transistor formed from the slab of monocrystalline silicon.
Dependencies are inferred from the claim text.