Semiconductor Emissions Abatement

1. Many of the process gases used are flammable or explosive such as H2 or SiH4, while others are poisonous such as COF2, HBr and F2 and must be treated before exposure to humans or wildlife.
2. Many gases used are dangerous for the environment such as tetrafluoromethane or carbon tetrafluoride (CF4) which have a lifetime of nearly 50,000 years in the atmosphere. They have a global warming impact 6,500 times that of CO2.
3. Waste gases contain particles or dust in the gas flow. This dust has the possibility to disrupt the facility exhaust systems leading to unintended downtime in the manufacturing plant.

Perfluorinated compounds (PFC’s) like CF4 are widely used in the semiconductor industry in dry processing applications such as film etching, chemical vapor deposition chamber cleaning and as a coolant for semiconductor manufacturing tools. The treatment of PFC’s before discharge to the atmosphere is a critical function of any abatement system. The main issue with many PFC’s is that they are extremely stable molecules. The strength of the PFC’s is the strongest single bond known in organic chemistry. It is extremely stable and requires large amounts of energy to break the molecules into constituent elements.

In order to crack the CF4 molecule temperatures of nearly 1,400 degrees C (2,552 degrees F) must be reached. In a reactor or burn box, fuel gas and oxygen provide both the energy and oxidant to allow the CF4 to breakdown.