Patent ID: 10401543

Abstract:
A type-II hybrid absorber photodetector (PD) is provided with ultrafast speed and high-power performance at terahertz (THz) regime. Through narrowed bandgap and enhanced absorption process at a type-II interface between absorption layers of gallium arsenic antimonide (GaAs0.5Sb0.5) and indium gallium arsenide (In0.53Ga0.47As), the incorporation of the type-II P+-GaAs0.5Sb0.5/i-In0.53Ga0.47As hybrid absorber in an indium phosphide (InP) UTC-PD obtains improvement in responsivity. Current blocking effect is minimized owing to the high-excess energy of photo-generated electrons injected from the GaAs0.5Sb0.5 layer to an InP-based collector layer. The flip-chip bonding packaged device shows a moderate responsivity along with a record wide optical-to-electrical bandwidth at 0.33 THz, among all the reported for long-wavelength ultrafast PDs. A saturation current exceeding 13 mA and a continuous-wave output power of −3 decibel-milliwatts are demonstrated at an operating frequency of 0.32 THz under an optical signal with a sinusoidal wave and a ˜63% modulation depth for PD excitation.