The Second Generation Shock Resistant And Thermally-Reliable Low Ag SAC Solder Doped With Mn
Authors: Vahid Goudarzi, Matthew Brown, Weiping Lin, Ning-Cheng Lee, and Jeffrey Chang Bing Lee Company: Motorola Mobile, Inc., Indium Corporation, and IST-Integrated Service Technology, Inc. Date Published: 10/13/2013
Abstract: 98.5Sn/0.5Ag/1Cu/0.05Mn (SAC0510M) exhibits a melting behavior similar to SAC105. It is two times better than SAC105 in the dynamic bending test; more than 8 times better in the modified JEDEC drop test; and more than 40-60% better in the - 55?C/125?C thermal cycling test. The reduced hardness and much thinner and stable IMC layer on Ni are responsible for the superior non-fragility, while the stabilized IMC and microstructure are responsible for the thermal cycling performance. A thinner IMC layer on Ni is more important than reduced hardness in improving non-fragility. The thermal cycling performance of SAC0510M may override SAC305. A high Tg brittle board causes poor drop test results due to pad cratering.