微觀組織的影響
(哈爾濱工業(yè)大學(xué) 現(xiàn)代焊接生產(chǎn)技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室，
哈爾濱 150001)
摘 要: 研究了塑料球柵陣列(PBGA)釬料球激光重熔以及紅外二次重熔過(guò)程中63Sn37Pb共晶釬料與Au/Ni/Cu焊盤之間界面反應(yīng)。結(jié)果表明：釬料凸點(diǎn)/焊盤界面處金屬間化合物的形貌和數(shù)量與激光輸入能量密切相關(guān)。隨著激光輸入能量的增大，Au完全溶解到釬料中，界面處連續(xù)分布的Au-Sn化合物層全部轉(zhuǎn)變?yōu)獒槧預(yù)uSn4相，部分針狀A(yù)uSn4從界面處折斷并落入釬料中，最后變?yōu)榧?xì)小的顆粒狀彌散分布在釬料內(nèi)部。 紅外二次重熔后焊點(diǎn)界面處的針狀A(yù)uSn4溶解到釬料中，釬料組織由原來(lái)的粒狀結(jié)晶結(jié)構(gòu)變?yōu)閷悠瑺罱Y(jié)晶結(jié)構(gòu)，焊點(diǎn)界面處出現(xiàn)了不同形態(tài)的粗大富Pb相。
關(guān)鍵字: 釬料球；激光重熔；釬料凸點(diǎn)；紅外重熔；焊點(diǎn)
secondary reflow on microstructure
of 63Sn37Pb/pad interface
（State Key Laboratory of Advanced Welding Production Technology,
Harbin Institute of Technology, Harbin 150001, China）
Abstract:Laser and infrared secondary reflow have obvious effects on the interfacial microstructure of 63Sn37Pb eutectic solder and Au/Ni/Cu pad. The results s how that the morphology of intermetallic compounds at interface is strongly influenced by laser input energy. With increase of laser input energy, Au dissolves in to the molten solder completely, and continuous Au-Sn intermetallics changes into needle-like AuSn4 phase. The needle-like AuSn4 is broken off from the interface and falls into the solder, and disappears from the interface finally. After secondary infrared reflow, needle-like AuSn4 dissolves into the solder as rod-shape. Microstructure of solder bulk changes from grain shape into lamella shape, and different shapes of Pb-rich islands appear at the interface.
Key words: solder ball; laser reflow; solder bump; infrared reflow; solder joint
