Electroless Bismuth Plating as a Peripheral Technology for SiC Power Devices

Abstract

Bismuth plated films have been used as a high-temperature joining in SiC power device because of their outstanding melting point. Electroless bismuth plating intended to have a “weak acidic” was investigated using Sn²⁺ ion as the reducing agent and citrate as the complexing agent. Complex baths exhibited good stability, and pure bismuth films were deposited. Experiments in polarization characteristics confirmed the mixed potential theory including local potential-current relationships for bismuth deposition.