Fig. 5From: High-speed Si-Ge avalanche photodiodesa Schematic cross-section of the resonant normal incident Si-Ge SACM APD [90]; b Measured APD RF impedance. The top is the real part and the bottom is the imaginary part. Inset is the equivalent circuit of the device avalanche region [91]; c Measured frequency response at different bias voltages under -20 dBm input optical power [73]; d Measured GBP versus gain under -20 dBm, -26 dBm and -30 dBm input optical powers [73]Back to article page