High speed and high responsivity germanium photodetector integrated in a Silicon-on-insulator microwaveguide

We report the experimental demonstration of a germanium metalsemiconductor-metal (MSM) photodetector integrated in a SOI rib waveguide. Femtosecond pulse and frequency experiments have been used to characterize such photodetectors. The measured bandwidth under 6V bias is about 25 GHz at 1.55 mu m wavelength with a responsivity as high as 1 A/W. The used technological processes are compatible with complementary-metal-oxide-semiconductor (CMOS) technology. (C) 2007 Optical Society of America.