通过激光辅助键合的无镍表面处理的Sn-Ag-Cu焊点的脆性断裂行为

Brittle Fracture Behavior of Sn-Ag-Cu Solder Joints with Ni-Less Surface Finish via Laser-Assisted Bonding.

作者信息

Han Seonghui, Han Sang-Eun, Lee Tae-Young, Han Deok-Gon, Park Young-Bae, Yoo Sehoon

机构信息

Regional Industry Innovation Department (Growth Engine), Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea.

School of Materials Science and Engineering, Andong National University, Andong 36729, Republic of Korea.

出版信息

Materials (Basel). 2024 Jul 22;17(14):3619. doi: 10.3390/ma17143619.

DOI:10.3390/ma17143619

PMID:39063910

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11279099/

Abstract

In this study, we investigated the brittle fracture behavior of Sn-3.0Ag-0.5Cu (SAC305) solder joints with a Direct Electroless Gold (DEG) surface finish, formed using laser-assisted bonding (LAB) and mass reflow (MR) techniques. Commercial SAC305 solder balls were used to ensure consistency. LAB increases void fractions and coarsens the primary β-Sn phase with higher laser power, resulting in a larger eutectic network area fraction. In contrast, MR produces solder joints with minimal voids and a thicker intermetallic compound (IMC) layer. LAB-formed joints exhibit higher high-speed shear strength and lower brittle fracture rates compared to MR. The key factor in the reduced brittle fracture in LAB joints is the thinner IMC layer at the joint interface. This study highlights the potential of LAB in enhancing the mechanical reliability of solder joints in advanced electronic packaging applications.

摘要

在本研究中，我们研究了采用激光辅助键合（LAB）和批量回流（MR）技术形成的、具有直接化学镀镍浸金（DEG）表面处理的Sn-3.0Ag-0.5Cu（SAC305）焊点的脆性断裂行为。使用商用SAC305焊球以确保一致性。随着激光功率的增加，LAB会增加孔隙率并使初生β-Sn相粗化，从而导致更大的共晶网络面积分数。相比之下，MR产生的焊点孔隙最少，金属间化合物（IMC）层更厚。与MR相比，LAB形成的焊点表现出更高的高速剪切强度和更低的脆性断裂率。LAB焊点脆性断裂减少的关键因素是接头界面处较薄的IMC层。本研究突出了LAB在提高先进电子封装应用中焊点机械可靠性方面的潜力。