PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

Expansion in technology urges for better advancement, thus resulting in miniaturization of electronic products with rising concern for the reliability of electronic packaging material. Lead-free solder, being one of the most prominent alternatives in the electronic packaging industry, is constantly exposed to harsh conditions, which are especially exacerbated with smaller solder joints and a closer pitch. Hence, with the effort of attaining a more reliable solder alloy, research has been intensively executed to overcome the hurdle of maximizing the potential of SAC solders. The scope of the review thus focuses on identifying the aptitude of bismuth-doped SAC solders by analyzing their microstructure evolution in isothermal aging while understanding their thermal and mechanical stability in different fatigue tests. In the earlier days, Bismuth was found to realize a better melting point when interacting with the tin matrix due to its unique solid solution-strengthening mechanism. Bismuth-doped solders can also induce a more robust solder joint with smaller IMC particles and a thinner interfacial layer that enables significant improvement in fatigue resistance compared to traditional SAC alloys. Therefore, the review concludes that bismuth-doped SAC solder tends to outshine the conventional alternative as well as offering immense advancement in thermal and mechanical properties, portraying them as a potential alternative for the assembly of high-reliability electronic products, especially in industries with extreme conditions such as aviation, automotive, and military.

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