Any of the organic compounds in which all of the hydrogen atoms attached to a carbon atom have been replaced by fluorine; also referred to as a perfluorocarbon. Fluorocarbons are usually gases or liquids at room temperature, depending on the number of carbon atoms in the molecule. A major use of gaseous fluorocarbons is in radiation-induced etching processes for the microelectronics industry; the most common one is tetrafluoromethane. Liquid fluorocarbons possess a unique combination of properties that has led to their use as inert fluids for cooling of electronic devices and soldering. Solubility of gases in fluorocarbons has also been used to advantage. For example, they have been used in biological cultures requiring oxygen, and as liquid barrier filters for purifying air.