MBE growth and characterization of type-II InAs/GaSb superlattices for mid-infrared detection

• Published in: Journal of crystal growth Vol. 274; no. 1; pp. 6 - 13
• Main Authors: Rodriguez, J.B., Christol, P., Cerutti, L., Chevrier, F., Joullié, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.2005; Elsevier
• Subjects: A3. Molecular beam epitaxy; A3. Superlattices; Applied sciences; B1. Antimonides; B3. Mid-infrared detector; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronics; Engineering Sciences; Exact sciences and technology; Multilayers, superlattices; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Optoelectronic devices; Photodetectors (including infrared and CCD detectors); Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; 78.66.Fd; 85.30.De; A3. Superlattices; B1. Antimonides; A3. Molecular beam epitaxy; B3. Mid-infrared detector; 81.15.Hi; 85.60.Gz; Atomic force microscopy; Binary compound; Gallium antimonides; Photoluminescence; 85.60.Gz A3. Molecular beam epitaxy; Crystal growth from vapors; RHEED; Inorganic compound; Size effect; Molecular beam epitaxy; Infrared detector; Experimental study; X ray diffraction; Indium arsenides; Absorption spectrum; Thickness; Solid source molecular beam epitaxy; Heterostructures; Superlattice; III-V semiconductors
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2004.09.088

Type-II InAs/GaSb superlattices (SLs) made of 10 InAs monolayers (MLs) and 10 GaSb MLs, designed to have a cut-off wavelength of 5.4 μm, have been grown on GaSb substrates by solid source molecular beam epitaxy (MBE). In order to obtain lattice-matched structures, a thin layer of InSb was inserted at the GaSb on InAs interface. We demonstrate that structural and optical properties of such structures strongly depend on the thickness of the InSb inserted layer. Strain-balanced InAs/GaSb SLs could be grown, after optimizing the MBE shutter sequence, by using a growth temperature of 390 °C and an inserted InSb layer of thickness 1 ML. Non-optimized pin diodes using 100 periods of such an SL as absorbing material showed an absorption coefficient varying from 4×10 3 to 6×10 3 cm −1 at room temperature in the 3–5 μm mid-infrared wavelength region, and a photovoltaic response up to 230 K.