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MARCH 2025 I PCB007 MAGAZINE 17 • e results from PCB shops using the same Type II gold electrolyte varied sig- nificantly. is variation underscored that factors such as incoming copper quality, process control, solder mask, and base material quality also play crucial roles in ENIG corrosion performance. Despite these variations, a clear trend emerged showing that Type II gold baths signifi- cantly reduce the occurrence of ENIG corrosion compared to Type I baths. • e third-generation gold electrolyte dem- onstrated the best performance, with no detectable corrosion in the investigated areas. is finding suggests that the lat- est generation of gold electrolytes, which incorporate a higher autocatalytic portion, can effectively eliminate corrosion issues. However, it also became evident that the gold electrolyte is just one of many factors influencing ENIG corrosion, as the same pro- cess operated at different sites can yield vary- ing results. So, we have the answer to the ques- tion we asked initially. Golden Hurdles for the Future As the electronics industry advances, the manufacturing processes for PCBs and IC substrates face significant challenges. Espe- cially the established gold finishes (ENIG and ENEPIG) will encounter several hurdles over the next decade. One primary challenge is the trend toward advanced miniaturization. As electronic devices become smaller and more powerful, the precision required for ENIG and ENEPIG coatings will increase. Ensuring uniformity and reliability on these smaller scales will demand advancements in deposition techniques. Omit- ting the nickel layer seems promising when entering very fine feature sizes and structures. Environmental regulations are also expected to become stricter, particularly concerning the chemicals used in these processes. is will necessitate the development of more eco- friendly alternatives and processes to comply with new standards, ensuring that manufactur- ing remains sustainable. Consequently, chem- ical suppliers are innovating greener options, such as lead-free nickel baths and cyanide-free gold solutions 3 . Cost management will be another critical issue. e rising costs of raw materials like gold, nickel, and palladium will push manu- facturers to innovate to reduce expenses with- out compromising quality. is could involve optimizing the deposition process or exploring alternative materials. Current efforts have been made to minimize the precious metal usage of palladium and gold in ENEPIG layers 4 . e complexity of the ENEPIG process, which involves three layers (nickel, palladium, gold), will need to be managed more effec- tively. Ensuring consistent quality and reducing the potential for defects during manufacturing is essential to maintain high standards. Having versatile gold, palladium, and nickel processes, which could be inter-combined for many appli- cations such as ENIG, ENEPIG, and EPAG in one plating line is at least a step towards reduc- ing shop floor complexity and processing 5 . Reliability under stress and enhanced signal