This study “PCB Surface Finishes & the Cleaning Process” was designed to investigate the effect of reflow and various cleaning agent types on ImSn, ImAg and ENIG surface finishes. Unpopulated ZESTRON® test vehicles, with the appropriate surface finish, were used for all trials. In a previous study by the authors, the OSP surface finish was analyzed for integrity within an aqueous-based cleaning system and was therefore excluded from this study.
Surface finish assessment following reflow and cleaning was conducted using visual inspection, adhesion test, copper test (ImAg and ImSn), nickel test (ENIG), and the X-Ray Fluorescence (XRF) test. Additionally, baseline tests were conducted on boards with all finish types without exposure to reflow or the cleaning process in order to assess the effect of the reflow process.