Epitaxially-grown Ge/Si avalanche photodiodes for 1.3 microm light detection.

We designed and fabricated Ge/Si avalanche photodiodes grown on silicon substrates. The mesa-type photodiodes exhibit a responsivity at 1310 nm of 0.54 A/W, a breakdown voltage thermal coefficient of 0.05%/ degrees C, a 3 dB-bandwidth of 10 GHz. The gain-bandwidth product was measured as 153 GHz. The effective k value extracted from the excess noise factor was 0.1.