We report a high-detectivity InAs quantum-dot infrared photodetector. The InAs quantum dots were grown by self-assembly on InP substrates via low-pressure metal-organic chemical-vapor deposition. Highly uniform quantum dots with a density of 4× 1010 cm2 were grown on a GaAsInP matrix. Photoresponse was observed at temperatures up to 160 K with a peak of 6.4 μm and cutoff of 6.6 μm. Very low dark currents and noise currents were obtained by inserting Al0.48 In0.52 As current blocking layers. The background-limited performance temperature was 100 K. A detectivity of 1.0× 1010 cm Hz12 W was obtained at 77 K with a bias of -1.1 V.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)