gallanylidynephosphane

Gallium phosphide (GaP), a phosphide of gallium, is a compound semiconductor material with an indirect band gap of 2.26 eV(300K). The polycrystalline material has the appearance of pale orange pieces. Undoped single crystal wafers appear clear orange, but strongly doped wafers appear darker due to free-carrier absorption. It is odorless and insoluble in water.
Sulfur or tellurium are used as dopants to produce n-type semiconductors. Zinc is used as a dopant for the p-type semiconductor.
Gallium phosphide has applications in optical systems. Its refractive index is between 4.30 at 262nm (UV), 3.45 at 550nm (green) and 3.19 at 840nm (IR).