Research on Germanium Photodetector with Multi-Mode Waveguide Input
Longsheng Wu,
Dongsheng Lv,
Nengyang Zhao,
Ruxue Wang,
Aimin Wu
Affiliations
Longsheng Wu
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
Dongsheng Lv
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
Nengyang Zhao
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
Ruxue Wang
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
Aimin Wu
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
In this work, a vertical N-I-P germanium (Ge) photodetector (PD) with a multi-mode waveguide input is presented. The fabricated devices exhibit a low dark current of 10 nA at bias of −1 V, and a high responsivity of exceeding 0.75 A/W over the wavelength range from 1270 to 1350 nm. High-frequency characteristics measurements show that the photodetector has a 3 dB opto-electrical (OE) bandwidth of 23 GHz under −3 V bias, which can be further improved by optimization of the photodetector configuration. A 50 Gb/s clear eye diagram with a non-return-to-zero (NRZ) modulation format is demonstrated. By using a single-mode excitation source, which is used to simulate light coming from the wavelength division multiplexing (WDM) devices, and sweeping its position, it is shown that the multi-mode input photodetector can be utilized in a WDM receiver to achieve both high responsivity and a flat-top passband.
