High speed and highly efficient Si optical modulator with strained SiGe layer

We developed a high speed and high efficiency of depletion type Si optical modulator (Si-MOD) with a pn junction by applying a p-type-doped strained SiGe layer which was slacked on the lateral pn junction type Si-MOD. We designed the optimum Si-MOD structure and demonstrated a very high modulation efficiency of 0.81 Vcm. which is one of die mosl efficient in Si-MODs with a pn junction. We also demonstrated u high speed operation of 25 Gbps for the Si-MOD al around 1.3 μm wavelength.