Silicon waveguide infrared photodiodes based on embedded nickel silicide particles

A novel CMOS-compatible infrared Si-waveguide photodetector, which utilizes photoemission from electrically floating metal silicide nanoparticles embedded in the space charge region of a Si p-n junction, is proposed. Numerical simulations show that absorption of infrared radiation in the particles can be dramatically enhanced due to resonant excitation of the localized surface plasmons on the particles, thus enabling to shrink the detector´s footprint to a submicron scale. A proof-of-concept device is fabricated using standard CMOS technology, exhibiting a peak responsivity of ~30 mA/W and a 3-dB bandwidth of ~6 GHz.