【摘要】 研究了过热度、冷却速率和时效处理对Sn-9Zn/Cu界面金属间化合物的形成及厚度的影响,并与同等条件下的Sn-3.5Ag-0.7Cu/Cu和Sn-37Pb/Cu界面作了比较。通过XRD、SEM及EPMA等检测发现,在Sn-9Zn/Cu界面上形成的金属间化合物可分为2层:近Cu侧的Cu-Zn化合物层和近焊料侧的Cu-Zn-Sn化合物层,同时在2层化合物的分界面上还检测出了大量的O。试验还发现,熔融过热度和冷却速率对焊料/Cu界面上金属间化合物的厚度有较大影响,随着熔融保温温度的升高和冷却速率的下降,厚度增加,且Sn-9Zn/Cu和Sn-3.5Ag-0.7Cu/Cu界面受熔融过热度和冷却速率的影响比Sn-37Pb/Cu界面大。在250℃+空冷的时效过程中,由于界面上Cu-Zn化合物层分解和Cu-Zn-Sn化合物层生长相互竞争,导致Sn-9Zn/Cu界面金属间化合物的厚度变化无明显规律。更多还原

【Abstract】 The effects of melt superheating degree,cooling rate and aging treatment on the formation and thickness of intermetallic compounds(IMC)in Sn-9Zn/Cu interface were investigated.For comparison,the interfaces of Sn-3.5Ag-0.7Cu/Cu and Sn-37Pb/Cu at the same condition were also examined.Two reaction layers are formed at the Sn-9Zn/Cu interface:Cu-Zn layer adjacent to Cu substrate,and Cu-ZnSn compound layer adjacent to the solder.In addition,O element is also detected at the interface between the Cu-Zn layer and Cu-Zn-Sn layer.The results also show that melt superheating degree and cooling rate have great effect on the thickness of the reaction layers.With increase of the melt superheating degree and the slower of cooling rate,the thickness of IMC formed at solder/Cu is increased.The reaction layers formed at the Sn-9Zn/Cu and Sn-3.5Ag-0.7Cu/Cu interfaces are affected by the melt superheating degree and cooling rate more greatly than that of Sn-37Pb/Cu.During aging process,there exists a mutual competition between the decomposition of Cu-Zn compound layer and the growth of CuZn-Sn compound layer,resulting in the irregular change of IMC layer thickness of the air-cooled Sn-9Zn/Cu.The mechanisms of the formation of IMC layer and its changes during aging were described.更多还原