Photodetector using surface-plasmon antenna for optical interconnect

Keishi Ohashi*, Junichi Fujikata

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contribution

3 Citations (Scopus)


We used a surface-plasmon antenna to obtain small photodetectors for LSI on-chip optical interconnection by using near-field light generated by the antenna. Such near-field devices are not constrained by the diffraction limit and they offer an approach to integrated nanoscale photonic devices. A small semiconductor structure is located near the antenna to absorb the near-field light. This structure can be made as small as the Schottky depletion layer, so the separation between electrodes can be reduced to almost the size of the near-field region. We have demonstrated a "Si nano-photodiode" or plasmon photodiode that uses the near-field localized in a subwavelength region, which is usually relatively large in size because of the long absorption length for Si (∼10 μm at a wavelength of ∼800 nm). The Si nano-photodiode has a fast impulse response with a full-width at half-maximum of ∼20 ps even when the bias voltage is small (∼1 V or less). We demonstrated an on-chip optical interconnect chip to operate circuitry in an LSI chip by using waveguide-coupled Si nano-photodiodes.

Original languageEnglish
Title of host publicationApplications of Group IV Semiconductor Nanostructures
Number of pages12
Publication statusPublished - 2008 Dec 1
Externally publishedYes
Event2008 MRS Fall Meeting - Boston, MA, United States
Duration: 2008 Dec 12008 Dec 5

Publication series

NameMaterials Research Society Symposium Proceedings
ISSN (Print)0272-9172


Conference2008 MRS Fall Meeting
Country/TerritoryUnited States
CityBoston, MA

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


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