The Korean Society of Surface Science and Engineering

The thermal stability of Cu surface anti-oxidation film is crucial for high-temperature electronic packaging, particularly in next-generation SiC and GaN power semiconductor devices operating at ≥ 200 ℃. This study examines two improved BTA-based inhibitors(AT-1, AT-5) under three industrial reflow environments-N₂ convection, formic acid conduction, and PFPE condensation-to evaluate their chemical, electrical, and mechanical stability. XPS and surface-resistance analyses confirmed that both inhibitors effectively suppressed Cu oxidation during reflow, though with a slight increase in resistance compared with bare Cu. AT-1 demonstrated superior oxidation inhibition in the formic-acid atmosphere, whereas AT-5 under N₂ conditions delivered the best overall performance, producing the thinnest oxide layer (similar to bare Cu), the lowest surface resistance, excellent solder wettability, and the highest bonding strength. In contrast, PFPE conditions resulted in significantly thicker oxide layers and the lowest bonding strengths for all samples. These findings highlight the strong dependence of BTA-based inhibitor stability on the reflow environment and provide practical guidance for selecting optimal anti-oxidation coatings in high-reliability power semiconductor packaging.

키워드 Corrosion inhibitor; Copper&Copper alloy; Power semiconductor; Benzotriazole.