Gallium Arsenide (GaAs)

Gallium arsenide (GaAs) is a III-V compound semiconductor formed from equal parts gallium and arsenic, engineered for optoelectronic and high-frequency applications where silicon reaches its limits. It is the primary material for high-efficiency solar cells (especially in space and concentrated photovoltaic systems), infrared LEDs, laser diodes, and monolithic microwave integrated circuits (MMICs) operating at microwave and millimeter-wave frequencies. Engineers select GaAs over silicon when direct bandgap emission, superior electron mobility at high frequencies, or radiation hardness is critical; it dominates aerospace, satellite communication, and fiber-optic infrastructure where its maturity and proven reliability justify higher material cost.