High Speed Metal–Oxide–Semiconductor Capacitor-Based Silicon Optical Modulators

Silicon photonics has recently attracted a great deal of attention because it offers an opportunity for low cost opto-electronic solutions for applications ranging from telecommunications down to chip-to-chip interconnect. One area of silicon photonics research that has seen an exceptional increase in activity and advancement is high speed silicon optical modulation. Within three years, modulation bandwidth has increased nearly three orders of magnitude from MHz range to 10 GHz range. This paper reviews two high speed silicon optical modulators with GHz bandwidth. It discusses in detail their design, performance, and limitations; and it outlines a path that can enable realization of further device improvements.