中溫銲料目前已廣泛應用於半導體封裝，以及汽車與電力電子產品中。它們特別適用於多階段組裝製程中的階段式焊接（Step soldering），並可在製程過程中減少半導體複合基板產生的缺陷。本研究所使用的銲料為 Sn-Ag-Cu-Bi-In 合金。相較於廣泛使用的 SAC305 銲料，添加 In 可提供固溶強化效果，使 Sn-Ag-Cu-Bi-In 銲料在高溫服役條件下仍能維持良好的可靠度。然而，在高溫儲存過程中觀察到界面金屬間化合物層厚度顯著增加，此現象可能會降低接點的機械強度。因此，本研究將奈米纖維素(Cellulose Nanofibers， CNFs)摻入 Sn-Ag-Cu-Bi-In 焊膏中，以觀察銲料/Ni與焊料/Cu界面IMCs 的成長。根據實驗結果，添加 CNFs 能有效抑制界面 IMCs 在迴焊後（As-reflowed）與高溫儲存試片中的成長。上述結果顯示，CNFs 的摻入可能有助於提升銲點的可靠度與機械強度。;Medium-temperature solders are currently widely applied in semiconductor packaging， as well as in automotive and power electronic products. They are particularly suitable for step soldering in multi-stage assembly processes and for mitigating defects in semiconductor composite substrates during fabrication. In this study， the solder alloy employed was a Sn-Ag-Cu-Bi-In alloy. Compared with the widely used SAC305 solder， the addition of In provides solid-solution strengthening， enabling Sn-Ag-Cu-Bi-In solder to maintain good reliability under high-temperature service conditions. However， significant growth in the thickness of the interfacial intermetallic compounds (IMCs) layer was observed during high-temperature storage， which may deteriorate the mechanical strength of the joint. Therefore， cellulose nanofibers (CNFs) were doped into the Sn-Ag-Cu-Bi-In solder paste to suppress solder/Ni and solder/Cu interfacial IMCs growth. The experimental results show that the doping of CNFs effectively suppresses the growth of interfacial IMCs in both as-reflowed and high-temperature storage specimens. These findings suggest that CNFs doping may enhance the reliability and mechanical strength of the solder joint.
