<p>Applications<br /> (1) High-purity boron trichloride is used in silicon semiconductor processing for diffusion doping (it decomposes at high temperature and boron diffuses into silicon to form a P-type semiconductor), ion implantation (as an ion source, boron is ionized under high energy and the boron ion beam is implanted to form a shallow P-type junction), and dry etching of Al, MoSi2, TaSi2, TiSi2, WSi and similar materials.<br /> (2) An excellent catalyst for many organic reactions (it is recommended for styrene polymerization, where it can raise yield and efficiency) and an intermediate for the pharmaceutical industry.<br /> (3) A basic material for organoboron compounds such as diborane and borate esters.<br /> A material for inorganic boron compounds: boron fiber, BN-fiber precursors, BN crucibles and similar products.<br /> Used to prepare boride powders: high-purity boron powder (amorphous and crystalline), BN, BC4 and TiB2 ultrafine powders.<br /> Used in CVD coating and film processes to deposit protective coatings and films of B, BC4, BN, TiB2 and similar materials.<br /> A basic material for optical fiber.<br /> It is also used in making solar-cell components and related processes.<br /> An epoxy curing agent.<br /> Boronizing during carbon-fiber graphitization.<br /> (4) Also used to purify metals such as aluminum, magnesium, zinc and copper alloys. It removes nitrides, carbides and oxides from molten metal. Treating molten aluminum with boron trichloride gas improves the properties of aluminum castings.<br /> (5) A flux for alloys of aluminum, iron, zinc, manganese, tungsten, Monel and similar metals.<br /> (6) Used to extinguish magnesium fires in heat-treatment furnaces.<br /> (7) In high-energy fuels and rocket propellants, boron trichloride is a boron source used to raise the BTU value.</p>