2016 Optical Society of America. Silicon-germanium (SiGe)-based avalanche photodiodes (APDs) have shown a significant improvement in receiver sensitivity compared to their IIIV counterparts due to the superior impact ionization property of silicon. However, conventional SiGe APDs typically operate at high voltages and low speed, limiting the application of this technology to data communication. In this paper, we present a waveguide SiGe avalanche photodiode using a thin silicon multiplication region with a breakdown voltage of 10 V, a speed of 25 GHz, and a gain-bandwidth product (GBP) of 276 GHz. At 1550 nm, sensitivities of 25 dBm and 16 dBm are achieved at 12.5 Gbps and 25 Gbps, respectively. This design will enable implementation of SiGe APDs for optical interconnects in data centers and high-performance computers, allowing significant reductions in aggregate system laser power (and therefore cost).