Silicon and Ge-on-Silicon PIN photodetectors for optical communications
Monolithic integration of silicon photodiodes with the high-speed and responsivity with the receiver electronics, can reduce the cost and improve the performance of short reach optical interconnects in data centers. We have reported silicon PIN photodiodes with 5x efficiency at 850nm wavelength and with 29 ps of FWHM by the implementation of photon trapping structures. Such characteristics leads to a higher signal to noise ratio required for optical links with possibility to operate them at 12.5 Gb/s (NRZ)
We have also demonstrated Germanium on Silicon photodetectors, s >80% at 1300 nm and 73% at 1550 nm with an intrinsic Ge layer of only 2 μm thickness. The broadband of absorption enhancement of such PDs covers the C and L bands, as well as a new data transmission window (1620–1700 nm), which can be used to enhance the capacity of conventional standard single-mode fiber cables. These photodiodes have potential for many applications, such as inter-/intra-datacenters, passive optical networks, metro and long-haul dense wavelength division multiplexing systems, eye-safe lidar systems, and quantum communications.