Octadecaborane

Octadecaborane is an inorganic compound, a borane with chemical formula B₁₈H₂₂. It is formed by oxidation of either the B₉H₁₂− anion or the B₂₀H₁₈2− anion. Ions, typically the positive ion B₁₈H₂₂+, can be used as a P type dopant through ion implantation for the manufacture of semiconductors. The molecule is ionized and accelerated, more or less intact (B₁₈H_x+), to the necessary energy to cause it to embed in the substrate to the desired depth. Once the octadecaborane molecule has been implanted, it breaks apart and most of the hydrogen atoms diffuse and escape the substrate leaving behind the boron atoms.