Carbon tetrafluoride is one of the most important etching gas for plasma etching silicon wafers in the microelectronic industry. It is also used as a low-temperature refrigeration gas, gas insulation, electronic device surface cleaning agents, solar cells and other applications. CF4 is a kind of stable, non-flammable and odorless gas with a good chemical stability and good heat conduction.
CF4 is prepared by direct fluorination of alkanes, chlorofluoromethane fluorination, hydrofluoromethane fluorination and direct synthesis of fluorocarbon. In the process of CF4 preparation, the reaction is exothermic and difficult to control. Therefore, special measures are necessary to prevent the exothermic reaction from happening.
Tetrafluoromethane is a potent greenhouse gas with an estimated atmospheric lifetime of 2300 to 50,000 years(SRC). Its 100 and 500 Year Global Warming Potential are 6500 and 8800, respectively(3).
It is a common air pollution hazard. High concentrations can have a narcotic effect and cause confusion, dizziness, headache and heart arrhythmias. It can displace air in confined spaces and act as a simple asphyxiant.
When contacted with hot surfaces or flames, it forms hydrofluoric acid. When flammable gases are mixed with the acid, they may explode violently.
The International Maritime Dangerous Goods Code provides detailed principles for transportation of hazardous chemicals. This code provides a general index of technical names for each hazardous substance and recommends specific practices for shipping each substance.
Tetrafluoromethane is soluble in water, but not in most organic solvents. It is also a photochemical hazard and should be kept away from light.