Metalloid
An element with properties intermediate between those of metals and non-metals, lying along the periodic table's staircase.
Unit
Dimensionless
In depth
Metalloids are typically brittle solids with a metallic lustre but semiconducting rather than metallic conductivity, which rises rather than falls with temperature. Doping them with tiny amounts of group 13 or 15 elements creates the p- and n-type materials on which all modern electronics depends.
Examples in the real world
Boron, silicon, germanium, arsenic, antimony and tellurium; silicon doped with phosphorus makes n-type semiconductor.