Jeong Haksan, Myung Woo-Ram, Sung Yong-Gue, Kim Kyung-Yeol, Jung Seung-Boo
School of Advanced Materials Science and Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu Suwon, 16419, South Korea.
Sungkyunkwan University Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu Suwon, 16419, South Korea.
J Nanosci Nanotechnol. 2018 Sep 1;18(9):6316-6320. doi: 10.1166/jnn.2018.15624.
Microstructures and mechanical property of Sn-3.0Ag-0.5Cu (SAC305) and epoxy Sn-3.0Ag-0.5Cu (epoxy SAC) solder joints were investigated with various surface finishes; organic solderability preservative (OSP), electroless nickel immersion gold (ENIG) and electroless nickel electroless palladium immersion gold (ENEPIG). Bending property of solder joints was evaluated by 3-point bend test method. Microstructure and chemical composition of solder joints was characterized by scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively. Epoxy did not effect on intermetallic compound (IMC) morphology. Scalloped shaped Cu6Sn5 IMC was observed at OSP surface finish. Chunky-like shaped and needle-like shaped (Ni,Cu)6Sn5 IMC were observed at the solder/ENIG joint and solder/ENEPIG joint, respectively. The bending cycles of SAC305/OSP joint, SAC305/ENIG joints and SAC305/ENEPIG joints were 720, 440 and 481 cycle numbers. The bending cycles of epoxy SAC and three types surface finished solder joints were over 1000 bending cycles. Under OSP surface finish, bending cycles of epoxy SAC solder was approximately 1.5 times higher than those of SAC305 solder joint. Bending cycles of epoxy SAC solder was over twice times higher than those of SAC305 solder with ENIG and ENEPIG surface finishes. The bending property of epoxy solder joint was enhanced due to epoxy fillet held the solder joint.
研究了具有不同表面处理（有机可焊性保护剂（OSP）、化学镀镍浸金（ENIG）和化学镀镍化学镀钯浸金（ENEPIG））的Sn-3.0Ag-0.5Cu（SAC305）和环氧Sn-3.0Ag-0.5Cu（环氧SAC）焊点的微观结构和力学性能。通过三点弯曲试验方法评估焊点的弯曲性能。分别用扫描电子显微镜（SEM）和能量色散X射线光谱仪（EDX）表征焊点的微观结构和化学成分。环氧树脂对金属间化合物（IMC）的形态没有影响。在OSP表面处理的焊点处观察到扇贝状的Cu6Sn5 IMC。在焊料/ENIG焊点和焊料/ENEPIG焊点处分别观察到块状和针状的（Ni,Cu）6Sn5 IMC。SAC-305/OSP焊点、SAC-305/ENIG焊点和SAC-305/ENEPIG焊点的弯曲循环次数分别为720、440和481次。环氧SAC和三种表面处理的焊点的弯曲循环次数超过1000次。在OSP表面处理下，环氧SAC焊料的弯曲循环次数比SAC305焊点高约1.5倍。环氧SAC焊料的弯曲循环次数比具有ENIG和ENEPIG表面处理的SAC305焊料高两倍以上。由于环氧圆角固定了焊点，环氧焊点的弯曲性能得到了增强。
