真空迴焊爐：實現可靠度高的大面積焊接

Vacuum Reflow Oven: Achieve high reliability welding over large areas

隨著高功率元件需求日益增加，大面積共晶接合技術（≧20 mm×20 mm）在汽車電子與航太晶片等高可靠性應用中的需求迅速攀升。雖然銀燒結技術憑藉其優異的熱導性與機械強度，已成為實現大面積接合的主流之一，然而其高昂的材料成本與嚴苛的製程條件，限制了其於大規模量產中的實用性。相較之下，錫膏結合真空回焊技術不僅成本較低，亦具備良好的製程穩定性與可擴展性，逐漸成為具備高度應用潛力的替代方案。然而，「空洞（void）」控制仍是大面積接合中的關鍵挑戰，對接合品質具有關鍵性影響。
本研究採用新型單腔式真空迴焊爐，成功於最大40 mm×40 mm接合面積下，實現最低3%空隙率的高品質接合。藉由系統性優化溫度曲線、真空壓力及其施加時機等關鍵製程參數，顯著提升了鍵結品質。本研究成果可為真空回焊技術導入大面積高可靠性構裝的實際應用與量產提供重要參考。

With the growing demand for high-power devices, the need for large-area eutectic bonding (≧20 mm×20 mm) has rapidly increased in high-reliability applications such as automotive electronics and aerospace chips. Although silver sintering has become a mainstream approach due to its excellent thermal conductivity and mechanical strength, its high material cost and stringent process conditions limit its practicality for mass production. In contrast, solder paste combined with vacuum reflow offers lower material costs and demonstrates superior process stability and scalability, emerging as a promising alternative. However, void control remains a critical challenge in large-area bonding, significantly affecting joint quality.
In this study, a novel single-chamber vacuum reflow oven was employed to achieve high-quality joints with a bonding area of up to 40 mm×40 mm and a void ratio as low as 3%. By systematically optimizing key process parameters—including the temperature profile, vacuum pressure, and vacuum timing—bonding quality was significantly improved. These results provide crucial insights for the practical application and mass production of vacuum reflow technology in large-area, high-reliability packaging.