| Title |
Influence of Nickel Thickness and Annealing Time on the Mechanical Properties of Intermetallic Compounds Formed between Cu-Sn Solder and Substrate |
| Authors |
김이슬(Yiseul Kim); 권지혜(Jeehye Kwon); 유다영(Dayoung Yoo); 박성규(Sungkyu Park); 이다정(Dajeong Lee); 이동윤(Dongyun Lee) |
| DOI |
https://doi.org/10.3365/KJMM.2017.55.3.165 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Pb-free solder; Intermetallic compound; mechanical properties; nanoindentation |
| Abstract |
Intermetallic compounds (IMCs) developed on the interface between a solder alloy and its bonding pads are an important factor in the failure of electronic circuits. In this study, the mechanical behaviors of the IMCs formed in the Cu-Ni-Sn ternary alloy system are investigated. Presumably, Ni can act as a diffusion barrier to Cu and Sn to form the IMCs. Detailed analysis of the microstructure is conducted using an electron probe micro-analyzer (EPMA). The addition of Ni softened the IMCs, which is determined based on the fracture toughness increasing (from 0.71 to 1.55 MPa√m) with the Ni layer thickness. However, above a critical amount of Ni involved in the Cu-Sn IMCs, the softening effect is diminished, and this could result from the segregation of Ni inside the IMCs. Therefore, the optimized condition must be determined in order to obtain a positive Ni effect on enhancing the reliability of the electronic circuits. (Received July 22, 2016; Accepted December 13, 2016) |