Metallisoideja

Metallisoideja, also known as metalloids, are chemical elements with properties intermediate between metals and nonmetals. They are typically solid at room temperature and brittle, with some metallic luster. Many metalloids have electrical conductivity between metals and nonmetals and behave as semiconductors, a trait central to modern electronics.

They tend to lie along a diagonal region of the periodic table between metals and nonmetals, though the exact boundaries vary by definition. Commonly cited metalloids include boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te); and sometimes polonium (Po) or astatine (At). They show multiple oxidation states and form covalent bonds; their bonding and properties are often intermediate.

Common uses include silicon in integrated circuits and solar cells; boron in glass and fiberglass; germanium in fiber optics and sensors; arsenic and antimony in compounds for electronics and flame retardants; tellurium in thermoelectrics and phase-change materials. They also exhibit semiconducting behavior that can be tuned by doping with impurities.

Because the definition of metalloids varies, some elements are contested; not all sources agree on which elements are metalloids, and several borderline elements are sometimes excluded or included.