The evaluation of sonochemical techniques for sustainable surface modification in electronic manufacturing

Purpose - This paper sets out to give an introduction to sonochemistry and the effects brought about by the application of ultrasound that might be useful in surface modification; and to show the feasibility of sonochemical surface modification in water on a range of materials employed in electronic manufacturing. Design/methodology/approach - Ultrasound was applied through DI water for the surface modification of four materials: a ceramic, a polyphenylene ester (polystyrene polymer (Noryl HM4025)), an acrylonitrile-butadiene-styrene/polycarbonate (ABS/PC-Cycolac S705), and an FR4 laminate (Isola Duraver 104). The efficacy of the treatment was determined by weight loss, scanning electronic microscopy, contact angle and roughness. Findings - Ceramic and Noryl materials can be surface modified sonochemically in DI water. Weight loss results suggested that, this was also the case for the Duraver laminate but the ABS/PC substrate was least affected by treatment in an ultrasonic field under these benign processing conditions. Originality/value - Traditional "wet" surface modification techniques often use hazardous chemistry, high-process temperatures, copious rinsing and long dwell times. This research programme addresses these issues by evaluating sonochemical surface modification techniques with the objective of producing a one-step process using benign chemistry at lower temperature with less rinsing.