Goldschmidt also synthesized gallium phosphide and gallium arsenide. Indium gallium phosphide is a solid solution of indium phosphide and gallium phosphide. Typical crystal materials are zinc telluride, gallium phosphide, and gallium selenide. Commercially significant products include gallium phosphide and indium phosphide. Indium phosphide (InP) is a binary semiconductor composed of indium and phosphorus. It is used standalone or together with gallium arsenide phosphide. Most InGaAs devices are grown on indium phosphide (InP) substrates. Gallium phosphide has applications in optical systems. The most used substrate is indium phosphide (InP). Deaths have resulted from accidental exposure to fumigation materials containing aluminum phosphide or phosphine. Zinc phosphide (ZnP) is an inorganic chemical compound. Calcium phosphide and zinc phosphide are similar poisons. Other pesticides similar to zinc phosphide are aluminium phosphide and calcium phosphide. Other pesticides similar to aluminium phosphide are zinc phosphide and calcium phosphide. Other pesticides similar to calcium phosphide are zinc phosphide and aluminium phosphide.