SEMICONDUCTOR DETECTORS: Germanium on silicon approaches III-V semiconductors in performance

摘要

Germanium-on-silicon photodiodes for communications have achieved performance that is close, if not equal, to that of commercial III-V detectors, and hold the promise of reduced cost and increased functionality in the future. Silicon photonics has been getting increased attention in the press as companies and universities report on advances that appear to be opening the door for widespread use of this technology in optical communications. While there is still some uncertainty about what the first high-volume application might be, developing the fundamental components is a necessary first step toward commercializing the technology. At Intel, research has been focused on demonstrating these building blocks, which include modulators, hybrid lasers, and photodetectors, together with passive waveguides to tie the devices together. While the press has devoted less attention to the photodetectors than the other components (the lasers in particular), advances in germanium-on-silicon (Ge/Si) photodiodes are proceeding apace (see Fig. 1).