GaSbAlSb

GaSbAlSb is not a single well-defined chemical compound. The term is used in two related contexts: (1) as a shorthand for heterostructures or superlattices formed by alternating layers of GaSb and AlSb, and (2) as a way to describe quaternary or mixed systems that combine GaSb and AlSb components. In practice, many devices described as GaSb/AlSb structures rely on epitaxially grown GaSb and AlSb layers rather than a fixed GaSbAlSb stoichiometry.

Both GaSb and AlSb crystallize in the zinc blende structure, which allows coherent interfaces when grown together. In GaSb/AlSb heterostructures, a GaSb quantum well can be confined between AlSb barriers, enabling electronic and optical confinement control through layer thickness and interface quality. The large difference in bandgaps between GaSb and AlSb provides a means to engineer infrared response, with carrier confinement and transition energies tunable by design.

Fabrication of GaSb/AlSb layers is typically performed by molecular beam epitaxy (MBE) or metal-organic chemical vapor deposition (MOCVD). Growth often starts on GaSb-compatible substrates, with buffer layers used to manage lattice mismatch and dislocations. Achieving sharp interfaces and controlling strain are important for device performance, and surface preparation, contamination control, and precise flux or flow-rate balancing are critical.

Applications for GaSb/AlSb-based structures include infrared optoelectronics such as detectors and emitters operating in near to mid-infrared, as well as fundamental studies of quantum wells and superlattices. The approach remains widely used in research and specialized device fabrication for wavelength-targeted applications. See also GaSb, AlSb, and III-V semiconductor heterostructures.