Adsorption/desorption studies of moisture on the <100> Si wafer surface were conducted using Atmospheric Pressure Ionization Mass Spectrometry (APIMS) and Electron Impact Mass Spectrometry (EIMS) with both regular and fully deuterated water. The resulting outgassing phenomena were modeled using a multilayer model which considers the distribution of chemisorbed and physisorbed moisture molecules and includes an oxidation term to account for the incorporation of moisture into the oxide at elevated temperatures. Moisture can also assist in the adsorption of organic impurities on the substrate surface under certain conditions. Studies were carried out by introducing isopropyl alcohol (IPA) to <100> silicon wafer surfaces challenged with deuterated water. It is proposed that the alcohol's hydroxyl group undergoes both replacement and esterification chemistries with the surface bound, dissociated, water molecules. Experimental results validating the proposed surface kinetics and mechanism is presented.
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