Solvent Design Methodology to Recycle Chamber Parts and Recover Platinum by Highly Selective Wet Treatment for Ni–Pt Sputtering System

In this paper, we describe a methodology of solvent design for selective removal of nickel–platinum (Ni–Pt) alloy film deposited on the surface of stainless-steel (SUS) chamber parts, based on electrochemistry. Several removal treatments were compared, such as sandblast-based physical treatment, pre sprayed aluminum lift-off treatment, and a newly proposed dilute-acid treatment. When using dilute acid with a redox potential between 0.75–0.85 V for Ni–Pt removal, no obvious damage was observed on the chamber parts after the treatment. The recycled parts were adequately worked in the sputtering chamber for mass production without causing the particle problem. Furthermore, we acquired losses of only 1.1% for platinum recovery efficiency in the Ni–Pt sputtering system.