We present the design, fabrication and characterization of a side-illuminated twin-waveguide pin-photodetector (twin-WGPD) on semi-insulating InP substrate in the 1.55 µm wavelength window. The measurement of the opto-electronic conversion parameter (S21) of the photodetector at a 1.55 µm window is carried out by an optical heterodyne technique which demonstrates 25 GHz bandwidths. The external responsivity of the pin-photodetector was measured at about 0.4 A W − 1 for a 60 µm long and 8 µm wide device.

Abstract-We present a pin-Traveling wave Photodetector (TWPD) on semi-insulating (SI) InP substrate at 1.55 µm wavelength window with an electrical bandwidth of more than 120 GHz, a line characteristic impedance of about 50 Ω, and microwave index matched to the optical group index. The internal quantum efficiency more than 99% for a 200 µm long device is determined. The layer stack of the TWPD has previously utilized in a semiconductor optical amplifier (SOA). The TWPD can be monolithically integrated with passive and active components such as arrayed waveguide grating (AWG), MachZehnder Interferometer (MZI), laser and modulator.