铜表面电沉积Ni（P）及其对Sn-Cu合金/Cu界面固相反应的影响

采用扫描电子显微镜（SEM）、电子能谱仪（EDS）、X射线衍射仪（XRD）研究了铜基体上电沉积Ni（P）层的结构以及Ni（P）层对电沉积Sn-Cu合金/Cu界面固相反应的影响。研究表明：电沉积Ni（P）层为非晶结构,含29%（原子）的P,经过225℃热处理转变成晶态Ni5P2。经过225℃热处理,Sn-Cu合金/Cu界面反应在界面处形成连续的Cu6Sn5及Cu3Sn层。而Sn-Cu合金/电沉积Ni（P）-Cu界面反应微弱,主要在Sn-Cu合金/Ni（P）界面前沿的Sn-Cu合金中形成棒状或块状（Ni,Cu）3Sn4,Cu基底不与Sn-Cu合金反应。电沉积Ni（P）合金层能有效阻挡Sn-Cu合金/Cu界面反应。

Electrodeposition of Ni(P) on Cu Substrate and Its Effect on Interfacial Solid Reaction Between Sn-Cu Alloy and Cu

Structure of the Ni（P） alloy layer electrodeposited on Cu substrate and effect of the electrodeposited Ni（P） layer on the Sn-Cu alloy/Cu interfacial solid reaction were studies using SEM,EDS and XRD.The results show that the electrodeposited Ni（P） layer is amorphous of 29 at.%P and transforms to crystalline Ni5P2 after annealing at 225 ℃.When annealing at 225 ℃,the Sn-Cu alloy/Cu interfacial reaction occurs to form continuous Cu6Sn5 and Cu3Sn layers along the Sn-Cu alloy/Cu interface.Comparatively,the interfacial reaction between Sn-Cu alloy and deposited Ni（P）-Cu substrate is weak,mainly form the bar/plate-like（Ni,Cu）3Sn4 particles embedded in the Sn-Cu alloy.The Sn-Cu alloy/Cu interfacial reaction does not take place,indicating the electroplated Ni（P） layer can effectively inhibit the Sn-Cu alloy/Cu interfacial reaction.