InAsGaSbbased

InAsGaSb-based materials refer to semiconductor systems that blend indium arsenide (InAs) and gallium antimonide (GaSb), typically described by the composition InAsxGa1−xSb or by InAs/GaSb heterostructures and superlattices. These III–V compounds crystallize in the zinc blende structure and are studied for infrared optoelectronic applications. By adjusting the As content and the relative layer thickness in superlattices, the electronic structure can be engineered for specific infrared responses.

A defining feature of InAsGaSb-based structures is the type-II broken-gap band alignment at the InAs/GaSb interface. In this arrangement, the conduction band minimum of InAs lies near or below the valence band maximum of GaSb, causing electrons and holes to reside in adjacent materials. This spatial separation enables tunable infrared absorption and emission, with bandgap engineering achieved through composition, strain, and layer design. The approach is commonly used in quantum wells and superlattices aimed at mid- to long-wavelength infrared detectors and emitters.

Growth and fabrication methods include molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD). Substrates such as GaSb or InAs are employed, and careful management of lattice and thermal mismatch is required to achieve high interface quality and low defect density. Interface abruptness, alloy uniformity, and strain balance are critical factors influencing device performance.

Applications span infrared imaging, night-vision systems, and spectroscopy, with particular emphasis on type-II superlattice infrared detectors and focal plane arrays. Ongoing research addresses material quality, device engineering, and integration with other platforms, as researchers continue to optimize performance and expand practical uses of InAsGaSb-based technologies.

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