Lists of metalloids Lists of metalloids This is a list of sources that each list metalloids: elements classified as metalloids. The sources are listed in chronological order. Lists of metalloids differ since there is no rigorous definition of metalloid (or its occasional alias, 'semi-metal'). Individual lists share common ground, with variations occurring at the margins. The elements most often regarded as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. Wikipedia generally categorises these six as metalloids, with the addition of astatine. Other sources may subtract from this list or add a varying number of other elements. This table show which elements are
Boron arsenide Boron arsenide Boron arsenide is a chemical compound involving boron and arsenic, usually with a chemical formula BAs. Other boron arsenide compounds are known, such as the subarsenide BAs. Chemical synthesis of cubic BAs is very challenging and its single crystal forms usually have defects. BAs is a cubic (sphalerite) semiconductor in the III-V family with a lattice constant of 0.4777 nm and an indirect band gap of approximately 1.86 eV. It can be alloyed with gallium arsenide to produce ternary and quaternary semiconductors. Cubic BAs is reported to decompose to the subarsenide BAs at temperatures above 920 °C. Boron