Ge-on-Si single-photon avalanche diode using a double mesa structure

We present experimental results of Ge-on-Si single-photon avalanche diodes based on a novel, to our knowledge, double mesa structure. Using this structure, the electric field at the mesa edges is suppressed compared to a traditional single mesa, leading to significant performance improvements. The dark current in linear mode shows a smaller increase for larger reverse voltages, resulting in a reduction by more than 260 times at low temperatures. Operated in the Geigermode at 110 K, the dark count rate in the double mesa is 100 times smaller. The devices achieve a dark count rate of 953 kHz, a single-photon detection efficiency of 7.3%, and a record-low jitter of 81 ps at an excess bias of 17.6% and a temperature of 110 K. Published by Optica Publishing Group under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.