Study of Size Effects on the Dynamic Resistance Variation and Microstructure Evolution of BGA Solder Joints During Electromigration

doi:10.3901/JME.260111

Abstract

Abstract: With the advancement of electronic information technology, the size effect in solder joints has become increasingly prominent. However, research on the evolution of electrical properties and microscopic mechanisms in microscale solder joints under electromigration remains notably insufficient. The growth behavior of interfacial intermetallic compound(IMC) and its size effect during the electromigration process of ball grid array(BGA) solder joints with different sizes are systematically examined.. The resistance of solder joints is dynamically and real-time monitored.. During the electromigration process, the IMC thickness at the anode of the solder joint is always greater than that at the cathode, and the larger size of the solder joint is easier to generate more IMC at the interface. The resistance of the solder joint rises and fluctuates in a zigzag or triangular shape during the electromigration. The increase of resistance is due to the expansion of holes and cracks, as well as the growth of a large number of IMCs inside the solder joint. Holes and cracks in the solder joint are found to heal during the electromigration, which reduces the resistance of solder joint. During the electromigration process, the defects inside the solder joints with larger size, such as cracks and holes, are more easily generated and expanded, and the growth of IMC is more intense, resulting in a higher resistance value. The results show that a distinct size effect is observed in BGA solder joints during electromigration, and the relationship between the resistance variation and microstructure evolution of solder joints is revealed.

Key words: dynamic resistance monitoring, size effects, electromigration, BGA solder joints

CLC Number:

TG156

WANG Wei, FENG Jiayun, WANG Shuai, WANG Taohan, TIAN Ruyu, TIAN Yanhong. Study of Size Effects on the Dynamic Resistance Variation and Microstructure Evolution of BGA Solder Joints During Electromigration[J]. Journal of Mechanical Engineering, 2026, 62(4): 126-134.

References

[1] WANG S，YAO Y，LONG X. Critical review of size effects on microstructure and mechanical properties of solder joints for electronic packaging[J]. Applied Sciences，2019，9(2)：227.
[2] NJOKU J E，AMALU E H，EKERE N，et al. Effects of reflow profile and miniaturisation on the integrity of solder joints in surface mount chip resistors[J]. Journal of Electronic Materials，2023，52：3786-3796.
[3] XU J，CAI C，PHAM V，et al. A comprehensive study of electromigration in lead-free solder joint[C]//2020 IEEE 70th Electronic Components and Technology Conference (ECTC). IEEE，2020：284-289.
[4] JEONG H，LEE C J，KIM J H，et al. Electromigration behavior of Cu core solder joints under high current density[J]. Electronic Materials Letters，2020，16：513-519.
[5] CHEN W J，LEE Y L，WU T Y，et al. Effects of electrical current and external stress on the electromigration of intermetallic compounds between the flip-chip solder and copper substrate[J]. Journal of Electronic Materials，2018，47：35-48.
[6] ANNUAR S，MAHMOODIAN R，HAMDI M，et al. Intermetallic compounds in 3D integrated circuits technology：A brief review[J]. Science and Technology of Advanced Materials，2017，18(1)：693-703.
[7] CHANG Y W，CHENG Y，XU F，et al. Study of electromigration-induced formation of discrete voids in flip-chip solder joints by in-situ 3D laminography observation and finite-element modeling[J]. Acta Materialia，2016，117：100-110.
[8] XIE H X，FRIEDMAN D，MIRPURI K，et al. Electromigration damage characterization in Sn-3.9 Ag-0.7 Cu and Sn-3.9 Ag-0.7 Cu-0.5 Ce solder joints by three-dimensional X-ray tomography and scanning electron microscopy[J]. Journal of Electronic Materials，2014，43：33-42.
[9] PARK J Y，LEE T，SEO W，et al. Electromigration reliability of Sn-3.0 Ag-0.5 Cu/Cu-Zn solder joints[J]. Journal of Materials Science：Materials in Electronics，2019，30：7645-7653.
[10] HUANG Z，JONES R E，JAIN A. Experimental investigation of electromigration failure in Cu-Sn-Cu micropads in 3D integrated circuits[J]. Microelectronic Engineering，2014，122：46-51.
[11] KADOGUCHI T，GOTOU K，YAMANAKA K，et al. Electromigration behavior in Cu/Ni-P/Sn-Cu based joint system with low current density[J]. Microelectronics Reliability，2015，55(12)：2554-2559.
[12] BAEK S M，PARK Y，OH C，et al. Modeling and experimental verification of intermetallic compounds grown by electromigration and thermomigration for Sn-0.7Cu solders[J]. Journal of Electronic Materials，2019，48：142-151.
[13] FENG J，HANG C，TIAN Y，et al. Effect of electric current on grain orientation and mechanical properties of Cu-Sn intermetallic compounds joints[J]. Journal of Alloys and Compounds，2018，753：203-211.
[14] WEI C C，CHEN C F，LIU P C，et al. Electromigration in Sn-Cu intermetallic compounds[J]. Journal of Applied Physics，2009，105(2)：023715.
[15] SUBRAMANIAN K N，CHAE S H，ZHANG X，et al. Electromigration statistics and damage evolution for Pb-free solder joints with Cu and Ni UBM in plastic flip-chip packages[J]. Journal of Materials Science：Materials in Electronics，2007，18：247-258.
[16] WANG F，ZHOU L，ZHANG Z，et al. Effect of Sn-Ag-Cu on the improvement of electromigration behavior in Sn-58Bi solder joint[J]. Journal of Electronic Materials，2017，46：6204-6213.
[17] MADANIPOUR H，KIM Y R，KIM C U，et al. Study of electromigration in Sn-Ag-Cu micro solder joint with Ni interfacial layer[J]. Journal of Alloys and Compounds，2021，862：158043.
[18] STRAUBINGER D，HURTONY T，GECZY A. Impact of electromigration and isothermal ageing on lead-free solder joints of chip-sized SMD components[J]. Journal of Materials Research and Technology，2022，21：308-318.
[19] FENG J，XU D E，TIAN Y，et al. SAC305 solder reflow：Identification of melting and solidification using in-process resistance monitoring[J]. IEEE Transactions on Components，Packaging and Manufacturing Technology，2019，9(8)：1623-1631.
[20] 马竟轩，王尚，杨东升，等. 纳米银焊膏热烧结及通电热老化过程动态电阻监测研究[J]. 机械工程学报，2020，56(8)：60-68. MA Jingxuan，WANG Shang，YANG Dongsheng，et al. Primary resonance analysis of solid and liquid mixture vibration isolation system[J]. Journal of Mechanical Engineering，2020，56(8)：60-68.
[21] FENG J，HANG C，TIAN Y，et al. Growth kinetics of Cu6Sn5 intermetallic compound in Cu-liquid Sn interfacial reaction enhanced by electric current[J]. Scientific Reports，2018，8(1)：1775.