galliumarsenidi

Gallium arsenide (GaAs) is a binary compound semiconductor formed from gallium and arsenic. It is widely used in electronics and optoelectronics due to its direct bandgap and high electron mobility.

At room temperature GaAs has a direct bandgap of about 1.42 eV, allowing efficient light emission. It crystallizes in the zinc blende structure and exhibits high electron mobility (approximately 8,500 cm^2/Vs) and a relatively high breakdown field, enabling high‑speed devices. The melting point is about 1,238 °C.

GaAs is used in infrared and near‑infrared light sources, including light‑emitting diodes and laser diodes, as well as photodetectors and solar cells. Its high electron mobility supports high‑frequency transistors and integrated circuits for wireless communications and radar. GaAs‑based heterostructures underpin many modern fiber‑optic and optoelectronic systems.

GaAs is grown commercially by methods such as the Czochralski process, the horizontal Bridgman method, and hydride vapor phase epitaxy for high‑purity bulk crystals. Epitaxial layers are commonly produced by molecular beam epitaxy (MBE) or metal‑organic chemical vapor deposition (MOCVD). Doping with silicon or tellurium yields n‑type materials, while zinc or cadmium introduces p‑type conductivity.

GaAs forms ternary and quaternary alloys with aluminum arsenide and indium arsenide, producing materials such as AlGaAs and InGaAs. These alloys enable heterostructures with engineered bandgaps, essential for laser diodes, photodetectors, and high‑efficiency multi‑junction solar cells.

Arsenic compounds are toxic; handling GaAs requires appropriate safety protocols, adequate ventilation, and proper waste disposal to minimize exposure to arsenic compounds during manufacturing and device fabrication.