The Vision 2000-A Residual Gas Analyzer (RGA) improves process productivity and product quality by providing real-time trace level monitoring of various gas species, including precursors, reaction byproducts, and contaminants during ALD and CVD processes. It can monitor the chamber baseline for air leaks and background contamination levels. In-situ monitoring of ALD and CVD processes can help characterize and prevent damage to production equipment and wafer yield loss owing to precursor concentration change, chamber leak or contamination.