Project Goal:

Feasiblity study on electronic-photonic integrated circuits for future applications

Project Status:

• 90-nm SOI CMOS pilot study completed in 2022
• 45-nm SOI CMOS and hybrid approaches in progress

Description:

Our research in silicon photonics targets the development of optical transceivers to be integrated in detector modules. Embedding of optical and electro-optical components monolithically in CMOS integrated circuits leads to very compact and power efficient solutions with low-parasitic electrical interconnects. In this way, data throughput-hungry imaging and tracking applications can greatly benefit and permits the design of all-silicon optical fiber-based module solutions.

In a first pilot study, a 90-nm silicon-on-insulator (SOI) CMOS technology was chosen to estimate space and performance parameters of such electronic-photonic integrated transceiver blocks. The transmitter block comprises a segmented travelling-wave Mach-Zehnder modulator coupled to a dual driver for optical 4-level pulse amplitude modulation (PAM-4). The receiver consists of a Ge photodiode followed by a multi-stage amplifier chain. Light is guided in and out utilizing low-loss edge couplers. From this pilot study, one can estimate data throughput capability of about 0.8 Tbps/cm² consuming about 7 pJ/bit and 0.8 pJ/bit for the transmitter and receiver blocks, respectively. The implementation of the transceiver functionality into a more sophisticated 45-nm Si photonics technology as well as a hybrid integration approach will also be evaluated.