CMOS-compatible planar silicon waveguide-grating-couplerphotodetectors fabricated on silicon-on-insulator (SOI) substrates

摘要

We report planar silicon interdigitated p-i-n photodiodes withnwaveguide-grating couplers fabricated on silicon-on-insulator (SOI)nsubstrates. The devices were fabricated in standard CMOS technology onn200-nm-thick SOI wafers with no additional fabrication steps. Anwaveguide-grating coupler with a period of 265 nm increased the quantumnefficiency by a factor of four compared to a photodiode without ancoupler. The dark current was 10 pA at -3-V bias and the bandwidth wasn4.1 GHz (RC limited)