Comparison of Segmented and Traveling-Wave Electro-Optical Transmitters Based on Silicon Photonics Mach-Zehnder Modulators

This paper presents a brief study of the two most commonly used topologies - segmented and traveling-wave - for realizing monolithically integrated electro-optical transmitters consisting of Si-photonics Mach-Zehnder modulators and their electrical drivers. To this end, two new transmitters employing high swing breakdown voltage doubler drivers were designed in the aforementioned topologies and compared with regard to their extinction ratio and DC power consumption at the data rate of 30 Gb/s. It is shown that for the targeted data rate and extinction ratio, a considerably lower power consumption can be achieved with the traveling-wave topology than with its segmented counterpart. The transmitters were realized in a 250 nm SiGe BiCMOS electronic-photonic integrated technology.