Aluminum arsenide ( as Al ) is a semiconductor material with almost the same lattice constant as gallium arsenide and aluminum gallium arsenide and wider band gap than gallium arsenide. ( AlAs ) can form a superlattice with gallium arsenide ( GaAs ) resulting in its semiconducting properties.  Because ( Ga As ) and ( Al As.)) have almost the same lattice constant, the layers have very little induced stretch, which allows them to be almost arbitrarily thick. This extremely high performance allows high electron mobility, HEMT transistors, and other quantum well devices.
It has the following properties:
- Thermal Expansion Coefficient 5 µm/(°C*m)
- Debbie temperature 417 K
- Microhardness 5.0 GPa (50g load)
- Number of atoms in 1 cm3 : (4.42-0.17x) 10 22 
- Bulk modulus (7.55+0.26x) 10 11 dyn cm −2 
- Hardness on the Mohs scale: ~5 
- Insolubility in H 2 O 
Aluminum arsenide is a III–V compound semiconductor material and an advantageous material for manufacturing optoelectronic devices such as light-emitting diodes.
Aluminum arsenide can be prepared using well-known methods, such as liquid- and vapor-phase epitaxy techniques or melt-growth techniques. However, aluminum arsenide crystals prepared by these methods are generally unstable and produce arsine (as H3) when exposed to moist air .
Little work has been done on the preparation of aluminum arsenide, mainly because of the practical difficulties involved. Due to the high melting point of the compound (about 1,700 °C) and the high reactivity of aluminum at this temperature, it is difficult to prepare from the melt. Some workers have prepared small crystals from the melt, and polycrystalline ingots have also been made. The best impurity carrier density of this material is of the order of 10 19/cm3 and is p – type . 
Aluminums arsenide is a stable compound; However, acids, acid fumes and moisture should be avoided. Hazardous polymerization will not occur. The decomposition of aluminums arsenide produces dangerous arsine gas and arsenic fumes.
The chemical, physical and toxicological properties of aluminum arsenide have not been thoroughly investigated and recorded.
Aluminum compounds have many commercial uses and are commonly found in industry. Many of these materials are chemically active and thus exhibit dangerously toxic and reactive properties.
Effects of exposure
Aluminum compounds have many commercial uses and are commonly found in industry. Many of these materials are chemically active and thus exhibit dangerously toxic and reactive properties. The chemical, physical and toxicological properties of aluminum arsenide have not been thoroughly investigated and recorded; However, there are few known chronic and acute symptoms based on chemical distribution.
Inhalation of aluminum arsenide can cause acute respiratory tract irritation. It can cause chronic arsenic poisoning, ulceration of the nasal septum, liver damage and cancers/diseases of the blood, kidney and nervous system. Aluminum arsenide is toxic if ingested and can cause gastrointestinal and skin effects and acute arsenic poisoning. Chronic effects of ingestion include arsenic poisoning, gastrointestinal disturbances, liver damage, and cancer/disease of the blood, kidney, and nervous system. If applied to the skin, aluminum arsenide can cause intense irritation, but no chronic health effects have been recorded.  [ page needed ]
Handling and Storage Precautions: Store in a cool, dry place in tightly closed containers. Make sure there is good ventilation. Open and handle the container carefully. Do not store together with acid. Keep the container tightly sealed.