High-detectivity quantum-dot infrared photodetectors grown by metalorganic chemical-vapor deposition

摘要

A mid-wavelength infrared photodetector based on InGaAs quantum dots buried in an InGaP matrix and deposited on a GaAs substrate was demonstrated. Its photoresponse at T = 77 K was measured to be around 4.7 μm with a cutoff at 5.5 μm. Due to the high peak responsivity of 1.2 A/W and low dark-current noise of the device, a specific peak detectivity of 1.1 X 10~(12) cm Hz~(1/2) W~(-1) was achieved at -0.9 V bias.