ABSTRACT
Since the 1987 Clean Air Act, when Government legislation forced the electronics industry to stop using the ozone depleting chemical Fréon® as a cleaner, the industry has been required to find new chemicals and processes. The industry believed at the time that Freon® solvent cleaning techniques effectively removed all surface contaminants. Subsequent research has shown that the old rosin based fluxes used in the manufacturing processes actually sealed in contaminants, whereas the new fluxes left contaminants exposed to react with humidity in the end-user environments. These inherent process residues must be removed to achieve product reliability.
