M

Metalloid

Quick Reference
Also Known AsSemimetal, semiconductor element, metalloid element

What is Metalloid?

An element with properties intermediate between metals and nonmetals, also called a semimetal. Metalloids include boron, silicon, germanium, arsenic, antimony, tellurium, and polonium. Silicon and germanium are important semiconductors. Their electrical conductivity is intermediate.

Properties & Characteristics

Metalloids (semimetals) are elements with properties intermediate between those of metals and nonmetals. They include: boron, silicon, germanium, arsenic, antimony, tellurium, and polonium (and sometimes selenium and astatine). Metalloids typically: have semiconducting electrical conductivity (intermediate between metals and insulators), form covalent compounds with nonmetals and ionic compounds with metals, and have some metallic lustre. Their band gap (0.1-3 eV) allows temperature-tunable conductivity.

Uses & Applications

Metalloids are critical in electronics: silicon and germanium are the primary semiconductor materials for transistors, solar cells, and integrated circuits. Arsenic and phosphorus are used as dopants in silicon semiconductors. Boron is used in nuclear reactor control rods and high-performance alloys.

Safety Information

Many metalloids are toxic: arsenic is a potent carcinogen (skin, lung, bladder cancer from chronic exposure); antimony compounds are irritants; selenium is an essential trace element but toxic at higher doses. Handle all metalloid compounds with appropriate PPE and ventilation. Silicon itself is generally inert, but silica dust causes silicosis.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Metalloid
Synonyms Semimetal, semiconductor element, metalloid element

Frequently Asked Questions

An element with properties intermediate between metals and nonmetals, also called a semimetal. Metalloids include boron, silicon, germanium, arsenic, antimony, tellurium, and polonium. Silicon and germanium are important semiconductors. Their electrical conductivity is intermediate.

More "M" Terms

View all "M" terms →
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z