An ultrafast optical modulator based on SiGe HBT

In this paper a novel configuration of optical modulator is presented. It combines the effect of fast electron-hole plasma injection obtained with a SiGe HBT together with the usage of a distributed Bragg reflector. Numerical simulations performed on a non-optimized device shows that the presence of the SiGe HBT enhances significantly the performances obtained with a similar device realized with and all-silicon pin diode. Switching speed higher than 1 GHZ have been numerically simulated.