Aluminium indium arsenide, also indium aluminium arsenide or AlInAs (
Alx In1−x As), is a
semiconductor material
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...
with very nearly the same
lattice constant
A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice, and is proportional to the distance between atoms in the crystal. A simple cubic crystal has o ...
as
GaInAs
Gainas (Greek: Γαϊνάς) was a Gothic leader who served the Eastern Roman Empire as ''magister militum'' during the reigns of Theodosius I and Arcadius.
Gainas began his military career as a common foot-soldier, but later commanded the bar ...
, but a larger
bandgap
In solid-state physics, a band gap, also called an energy gap, is an energy range in a solid where no electronic states can exist. In graphs of the electronic band structure of solids, the band gap generally refers to the energy difference (i ...
. The ''x'' in the formula above is a number between 0 and 1 - this indicates an arbitrary
alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductilit ...
between
InAs and
AlAs.
The formula ''AlInAs'' should be considered an abbreviated form of the above, rather than any particular ratio.
Aluminium indium arsenide is used e.g. as a buffer layer in
metamorphic HEMT transistors, where it serves to adjust the lattice constant differences between the
GaAs
Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure.
Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circ ...
substrate and the
GaInAs
Gainas (Greek: Γαϊνάς) was a Gothic leader who served the Eastern Roman Empire as ''magister militum'' during the reigns of Theodosius I and Arcadius.
Gainas began his military career as a common foot-soldier, but later commanded the bar ...
channel. It can be also used to form alternate layers with
indium gallium arsenide
Indium gallium arsenide (InGaAs) (alternatively gallium indium arsenide, GaInAs) is a ternary alloy (chemical compound) of indium arsenide (InAs) and gallium arsenide (GaAs). Indium and gallium are ( group III) elements of the periodic table wh ...
, which act as
quantum well
A quantum well is a potential well with only discrete energy values.
The classic model used to demonstrate a quantum well is to confine particles, which were initially free to move in three dimensions, to two dimensions, by forcing them to occupy ...
s; these structures are used in e.g. broadband
quantum cascade laser Quantum-cascade lasers (QCLs) are semiconductor lasers that emit in the mid- to far-infrared portion of the electromagnetic spectrum and were first demonstrated by Jérôme Faist, Federico Capasso, Deborah Sivco, Carlo Sirtori, Albert Hutchinson, ...
s.
Safety and toxicity aspects
The toxicology of AlInAs has not been fully investigated. The dust is an irritant to skin, eyes and lungs. The environment, health and safety aspects of aluminium indium arsenide sources (such as
trimethylindium
Trimethylindium, often abbreviated to TMI or TMIn, is the organoindium compound with the formula In(CH3)3. It is a colorless, pyrophoric solid. Unlike trimethylaluminium, but akin to trimethylgallium, TMI is monomeric.
Preparation
TMI is prepared ...
and
arsine
Arsine (IUPAC name: arsane) is an inorganic compound with the formula As H3. This flammable, pyrophoric, and highly toxic pnictogen hydride gas is one of the simplest compounds of arsenic. Despite its lethality, it finds some applications in ...
) and industrial hygiene monitoring studies of standard
MOVPE
Metalorganic vapour-phase epitaxy (MOVPE), also known as organometallic vapour-phase epitaxy (OMVPE) or metalorganic chemical vapour deposition (MOCVD), is a chemical vapour deposition method used to produce single- or polycrystalline thin films. ...
sources have been reported recently in a review.
[Environment, health and safety issues for sources used in MOVPE growth of compound semiconductors; D V Shenai-Khatkhate, R Goyette, R L DiCarlo and G Dripps, Journal of Crystal Growth, vol. 1-4, pp. 816-821 (2004); ]
References
{{DEFAULTSORT:Aluminium Indium Arsenide
III-V semiconductors
III-V compounds
Arsenides
Aluminium compounds
Indium compounds
Zincblende crystal structure