This article reviews the way in which Novellus Systems has addressed several important environmental issues. Emissions of global-warming gases, such as PFCs, need to be reduced by significant amounts by semiconductor device manufacturers by the year 2010. In addition to PFCs, HF and F₂ emissions must also be reduced. These emissions come primarily from chamber clean processes. Novellus has developed chamber clean processes that demonstrate dramatic reductions in emissions of both, solving two environmental problems at once.