GaAsPllä

GaAsPllä is a term used in some contexts to denote gallium arsenide phosphide alloys, GaAs1−xPx, a ternary semiconductor alloy in which phosphorus partially substitutes arsenic in the GaAs lattice. The name is not widely standardized; in most English-language literature the material is referred to as GaAsP or GaAs1−xPx.

Crystal structure and properties: GaAsPllä shares the zinc blende structure typical of GaAs and GaP. As the phosphorus content x increases, the lattice constant decreases slightly and the bandgap widens from about 1.43 eV (GaAs) toward about 2.26 eV (GaP). For many compositions the alloy remains a direct-bandgap semiconductor, which is favorable for light emission and optoelectronic applications. Refractive index and carrier dynamics are intermediate between those of GaAs and GaP, depending on composition and strain.

Fabrication and growth: The alloy is typically grown by epitaxial methods such as metal-organic vapor-phase epitaxy (MOVPE/MOCVD) or molecular-beam epitaxy (MBE), often on GaAs or silicon substrates with buffer layers to manage lattice mismatch. Precise control of x allows tuning of optical and electrical properties. Doping is performed with conventional n-type or p-type dopants (for example Si or Zn). Strain and defects from lattice mismatch can influence mobility and recombination.

Applications: GaAsPllä enables bandgap engineering for optoelectronic devices, including light-emitting diodes, laser diodes, photodetectors, and tandem solar cells where a tailored bandgap improves efficiency.

Safety and handling: As-containing materials require appropriate safety measures and handling protocols in fabrication environments.

See also: GaAs, GaP, GaAsP, compound semiconductors.