2013 年 64 巻 2 号 p. 140-145
A 1-octadecanethiol self-assembly monolayer（ODT-SAM）was formed on electroless Au/Ni-P layers to improve corrosion resistance. However, ethanolic solutions are inferior to aqueous solution in terms of safety and cost. For this study, ODT-SAMs were obtained from aqueous solutions. A nonionic surfactant was used to dissolve ODT in water. The adsorption of ODT was evaluated based on the contact angle of water. The corrosion resistance was evaluated using the salt spray test. The corrosion resistance of ODT-SAMs obtained by immersion for 300 s in an aqueous micellar solution of the surfactant concentration of at least 2.3 × 10－1 mol/L and the ODT concentration of 5.0 × 10－3 mol/L was equival ent to that of ODT-SAMs from ethanolic solutions. The formation status of the ODT-SAMs was examined using infrared reflection absorption spectroscopy. The structure of ODT-SAMs on a gold plated surface in an aqueous micellar solution was compared to that of ODT-SAMs on a gold plated surface in an ethanol solution, revealing no difference. No deterioration in bondability was observed when the solder-ball bondability and wire bondability of an Au/Ni-P substrate on which ODT-SAMs obtained from an aqueous micellar solution were formed. Results show that ODT-SAMs obtained from aqueous micellar solutions are useful as corrosion inhibitors for electroless Au/Ni-P layers used in printed wiring boards.