Ge on Si avalanche photodetectors

Research Area: Silicon photonics for telecom, datacom and interconnect

Main Researcher: Hongtao Chen

Avalanche photodetectors (APD) provide higher sensitivity than their classical PIN detector counterparts. This can have a major impact on the link budget in silicon photonics interconnects. Germanium detectors are readily integrated on the silicon photonics platform. In order for Germanium-based APDs to be readily integrated with CMOS electronics, low bias voltages are required. In this work Germanium avalanche photodetectors are studied with the aim of realizing low-voltage operation (-4V) and high sensitivity (-30dBm). We focus on conventional PIN structures due to their lower dark current compared to that of MSM structures. The baseline lateral PIN-based APD device is shown in Fig. 1(a), and TCAD simulation results for doping distribution and electric field distribution in Fig. 1(b).

Fig. 1. Germanium-based PIN APD

Other people involved:

• Joris Van Campenhout
• Hongtao Chen

PhD thesises