Integrating a high performance Germanium photodiode into a CMOS compatible flow for a full monolithic Silicon Photonics solution

The insatiable demand for digital information has led to the introduction and increasing adaptation of Silicon Photonics in digital communications to replace the much slower copper wires wherever possible. While most of today’s Silicon Photonics solutions are being manufactured using hybrid (no CMOS devices) integration, there is an increasing need to offer full integrated solutions (CMOS and Photonics) to improve system level performance and drive overall costs down. In this paper we’ll describe the challenges and innovative solutions used to develop and ultimately integrate a high performance Germanium (Ge) photodiode (PD) into a 90nm CMOS compatible process flow to provide a full monolithic Silicon Photonics solution.