Halocarbon-41 Methyl fluoride

Fluoromethane, also known as methyl fluoride, Freon 41, Halocarbon-41 and HFC-41, is a non-toxic, liquefiable, and flammable gas at standard temperature and pressure. It is made of carbon, hydrogen, and fluorine. The name stems from the fact that it is methane (CH₄) with a fluorine atom substituted for one of the hydrogen atoms.

It is used in the manufacture of semiconductor and electronic products. In the presence of an RF field fluoromethane will dissociate into fluoride ions that selectively etch silicon compound films (reactive-ion etching).