Open Access Nano Express

Growth and fabrication of InAs/GaSb type II superlattice mid-wavelength infrared photodetectors

Jianxin Chen*, Qingqing Xu, Yi Zhou, Jupeng Jin, Chun Lin and Li He

Author Affiliations

Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai, 200083, China

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Nanoscale Research Letters 2011, 6:635  doi:10.1186/1556-276X-6-635

Published: 22 December 2011

Abstract

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.

Keywords:
InAs/GaSb; type II superlattice; photodiodes; infrared