Aluminium arsenide, with the chemical formula AlAs, is a binary compound composed of aluminium (Al) and arsenic (As). It belongs to the III-V group of semiconductors in the periodic table, where elements from group III (aluminium) and group V (arsenic) combine to form various semiconductor materials.

Aluminium arsenide is an important semiconductor material with unique electronic properties. It is a direct bandgap semiconductor, which means that it efficiently emits and absorbs light. This property makes it valuable for various electronic and optoelectronic applications.

Some key characteristics and applications of aluminium arsenide include:

1. High Electron Mobility: Aluminium arsenide exhibits high electron mobility, making it suitable for use in high-speed electronic devices, especially in high-frequency applications like microwave and radio-frequency devices.
2. Laser Diodes: Aluminium arsenide is used in the construction of semiconductor laser diodes, particularly in the near-infrared wavelength range. Laser diodes made from aluminium arsenide are utilized in telecommunications, optical data storage, and other applications where light emission is required.
3. Solar Cells: Aluminium arsenide is also employed in multi-junction solar cells, which are used in concentrated photovoltaic systems to improve energy conversion efficiency.
4. Heterojunctions and Quantum Wells: Aluminium arsenide is often combined with other semiconductor materials, like gallium arsenide (GaAs), to create heterojunctions and quantum wells. These structures are utilized in advanced electronic and optoelectronic devices due to their unique energy band structures.

It is essential to handle aluminium arsenide with care, as with other semiconductor materials containing toxic elements. Proper safety precautions should be taken during its synthesis, processing, and handling.

Aluminium arsenide has contributed significantly to the advancement of semiconductor technology, particularly in the field of optoelectronics and high-speed electronic devices. As with other semiconductors, research into aluminium arsenide continues to explore new applications and improve its properties for future technological developments.