微小互连Cu-Sn界面钎焊及接头剪切行为

A study on Cu-Sn soldering and shear behavior of solder joints with micro interconnection

关键词:  Cu-Sn界面|钎焊|剪切行为|微小互连

Key words:  Cu-Sn interface|soldering|shear behavior|micro interconnection

摘要:

针对Cu-Sn-Cu三明治结构，进行0.06 MPa恒压钎焊. 基于Cu-Sn二元相图，选定了不同的钎焊温度与钎焊时间. 钎焊完成后，根据不同相组成可将接头分为残余锡，Cu₃Sn-Cu₆Sn₅-Cu₃Sn，Cu-Cu₃Sn-Cu三类. 为研究三种不同相组成接头抗剪强度之间的关系，进行1 mm/min加载速率的剪切试验，并对断口进行形貌分析. 结果表明，随着Sn与Cu₆Sn₅相继耗尽，接头抗剪强度不断升高. 残余锡接头，Cu₃Sn-Cu₆Sn₅-Cu₃Sn接头，Cu-Cu₃Sn-Cu接头抗剪强度分别为23.26，33.59，51.83 MPa. 分析断口形貌发现，在残余Sn接头断口中，可以分辨出Sn，Cu₆Sn₅，Cu₃Sn形貌，说明其断裂路径穿过了Cu₆Sn₅与Cu₃Sn两相. 在Cu₃Sn-Cu₆Sn₅-Cu₃Sn接头断口中，可分辨出Cu₆Sn₅，Cu₃Sn形貌，其断裂路径穿过了Cu₃Sn相. 全Cu₃Sn相接头断口中仅可分辨出Cu₃Sn相断裂形貌.

Abstract:

This study focuses on the Cu-Sn-Cu sandwich structure soldering, 0.06 MPa constant pressure. Different soldering temperatures and soldering times were selected based on the Cu-Sn binary phase diagram. After soldering according to different phase composition the solder joints can be divided into three types of residual Sn/Cu₃Sn-Cu₆Sn₅-Cu₃Sn/Cu-Cu₃Sn-Cu. The relationship among shear strength of solder joints and three different phases compositions were researched by shear experiment of 1 mm/min loading rate and fracture morphology analysis. The results show that the shear strength of solder joints increases with the depletion of Sn and Cu6Sn5 in sequence. The shear strength of residual Sn solder joints, Cu₃Sn-Cu₆Sn₅-Cu₃Sn solder joints and Cu-Cu₃Sn-Cu solder joints are 23.26, 33.59, 51.83 MPa, respectively. Based on the fracture morphology analysis, residual Sn solder joint fracture can distinguish the morphology of Sn/Cu₆Sn₅/Cu₃Sn, indicating that the crack path through the Cu₆Sn₅ and Cu₃Sn phases. In Cu₃Sn-Cu₆Sn₅-Cu₃Sn solder joint fracture, Cu₆Sn₅/Cu₃Sn morphology was distinguished, crack path through the Cu₃Sn phase. When only Cu₃Sn phase was at solder joints, was Cu₃Sn only Cu₃Sn can be seen in fracture morphology of the soldering joints.