Growth and fabrication of InAs/GaSb type II superlattice mid-wavelength infrared photodetectors
Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai, 200083, China
Nanoscale Research Letters 2011, 6:635 doi:10.1186/1556-276X-6-635Published: 22 December 2011
We report our recent work on the growth and fabrication of InAs/GaSb type II superlattice photodiode detectors. The superlattice consists of 9 monolayer InAs/12 monolayer GaSb in each period. Lattice mismatch between the GaSb substrate and the superlattice is 1.5 × 10-4. The full width at half maximum of the first-order satellite peak from X-ray diffraction is 28 arc sec. The P-I-N photodiodes in which the absorption regions (I regions) have 600 periods of superlattice show a 50% cutoff wavelength of 4.3 μm. The current responsivity was measured at 0.48 A/W from blackbody radiation. The peak detectivity of 1.75 × 1011 cmHz1/2/W and the quantum efficiency of 41% at 3.6 μm were obtained.
PACS: 85.60.-q; 85.60.Gz; 85.35.-Be.