SIMULATION AND ANALYSIS OF SILICON ELECTROOPTIC MODULATORS UTILIZING THE CARRIER-DISPERSION EFFECT AND IMPACT-IONIZATION MECHANISM

A new type of Si guided-wave electro-optic modulator is proposed and a nalyzed. The modulator makes use of the impact-ionization mechanism fo r carrier generation, and the carrier-dispersion effect for electro-op tic conversion. Both electrical and wave propagation properties of the modulator were examined by a two-dimensional device simulator and a t hree-dimensional waveguide simulator, respectively. Numerical estimate s of phase modulation due to refractive-index change and intensity mod ulation due to optical absorption and radiation loss were obtained. On e of important features of the prospected modulator is speed. The simu lated turn-on and turn-off time of the modulator was less than 1 ns. G Hz modulation is, therefore, possible for this class of modulators wit h device structure and doping profiles optimized for fiber coupling.