High-speed-performing pin photodetectors with lateral silicon- germanium-silicon heterojunctions for 1.55 µm communications

International audienceWe investigate the properties of high-speed waveguide photodetectors with hetero-structured Silicon-Germanium-Silicon junctions monolithically integrated on Silicon-on-Insulator substrates. These devices take advantage of unique integration strategy that combines butt-waveguide-coupling and lateral Silicon-Germanium-Silicon pin junctions. Fabrication is robust and fully compatible with complementary metal-oxide-semiconductor technology. The resulting devices have improved responsivity and bandwidth performances. In particular, a responsivity up to 1.2 A/W and a dark-current as low as 100 nA under 1V reverse bias are experimentally demonstrated with a set of pin photodetectors. Furthermore, fast device opto-electrical responses lead to an excellent on-chip detection capability well-suited for future high-speed link traffics up to 40 Gbps. An errorless operation is achieved for established 10 Gbps and 25 Gbps data rates, providing a power sensitivities of-13.9 dBm and-11.3 dBm with a bit-error-rate of 10-9