High-performance Si optical modulator with strained p-SiGe layer and its application to 25 Gbps optical transceiver

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 stacked on the lateral pn junction type Si-MOD. We designed the optimum Si-MOD structure and demonstrated a high modulation efficiency of 1.0 Vcm, which is about 50% more efficient than that of Si-MOD with a lateral pn junction. We also demonstrated a high speed operation of 25 Gbps for the Si-MOD at around 1.3 μm wavelength with CMOS-driver and high-performance Ge photodetector (Ge-PD) integration.