Gaseous species in the exhaust from the ALD chamber were measured using a Hiden Analytical HPR-30 residual gas analysis (RGA) vacuum process sampling system that includes a HAL 201 RC mass spectrometer (MS) with a Faraday Cup detector. The RGA system was connected approximately 80 cm from the substrate stage, with gas lines maintained at room temperature since no residue condensation along the lines was noted. The MS analysis involved collecting both scan spectra and multiple ion detection (MID) of specific ions with electron impact ionization set at 70 eV to ensure efficient reactant molecule fragmentation, enabling the detection and analysis of gas-phase reaction products. The system was differentially pumped and the operating pressure during typical measurements is kept in the order of 10 -6 mbar to enable mean free paths that allow collisionless particle transport of the ions from the orifice to the detector.