Ge-on-insulator lateral p-i-n waveguide photodetectors for optical communication

• Main Authors: Cheng, Chin-Yuan, Tsai, Cheng-Hsun, Yeh, Po-Lun, Hung, Sheng-Feng, Bao, Shuyu, Lee, Kwang Hong, Tan, Chuan Seng, Chang, Guo-En
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2020
• Subjects: Engineering::Electrical and electronic engineering::Semiconductors; Germanium; Photodetector
• Online Access: https://hdl.handle.net/10356/145188
• Institution: Nanyang Technological University

We report high-performance lateral p-i-n Ge waveguide photodetectors (WGPDs) on a Ge-on-insulator (GOI) platform that could be integrated with electronic-photonic integrated circuits (EPICs) for communication applications. The high quality Ge layer affords a low absolute dark current. A tensile strain of 0.144% in the Ge active layers narrows the direct bandgap to enable efficient photodetection over the entire range of C- and L bands. The low-index insulator layer enhances optical confinement, resulting in a good optical responsivity. These results demonstrate the feasibility of planar Ge WGPDs for monolithic GOI-based EPICs.