Investigation of Intermetallic Compound Growth Enhanced by Electromigration in Pb-Free Solder Joints

2007 ◽  
Author(s):  
Seung-Hyun Chae ◽  
Brook Chao ◽  
Xuefeng Zhang ◽  
Jay Im ◽  
Paul S. Ho
Keyword(s):  
Intermetallic Compound ◽  
Solder Joints ◽  
Intermetallic Compound Growth ◽  
Free Solder

Effect of Solder Joint Thickness on Intermetallic Compound Growth Rate of Cu/Sn/Cu Solder Joints During Thermal Aging

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Yan Zhu ◽  
Fenglian Sun
Keyword(s):  
Growth Rate ◽  
Intermetallic Compound ◽  
Solder Joint ◽  
Aging Time ◽  
Thermal Aging ◽  
Solder Joints ◽  
Control Element ◽  
Joint Thickness ◽  
Intermetallic Compound Growth ◽  
Peak Value

The sandwich structure Cu/Sn/Cu solder joints with different thicknesses of the solder layers (δ) are fabricated using a reflow solder method. The microstructure and composition of the solder joints are observed and analyzed by scanning electron microscopy (SEM). Results show that the thickness of intermetallic compound (IMC) and Cu concentration in the solder layers increase with the decrease of δ after reflow. During thermal aging, the thickness of IMC does not increase according to the parabolic rule with the increase of aging time; the solder joint thickness affects markedly the growth rate of IMC layer. At the beginning of thermal aging, the growth rate of IMC in the thinner solder joints (δ ≤ 25 μm) is higher than that in the thicker ones (δ ≥ 30 μm). The growth rate of IMC (δ ≤ 25 μm) decreases in the thinner solder joints, while increases in the thicker solder joints (δ ≥ 40 μm) and is nearly invariable when the δ equals to 30 μm with aging time extending. The growth rate of IMC increases first and then decreases after reaching a peak value with the increase of δ in the later stage during aging. The main control element for IMC growth transfers from Cu to Sn with the reduction of size.

Influence of Second Reflow on the Intermetallic Compound Growth with Different Surface Finish

2016 ◽  
Vol 701 ◽  
pp. 127-131
Author(s):  
Hardinnawirda Kahar ◽  
Zetty Akhtar Abd Malek ◽  
Siti Rabiatull Aisha Idris ◽  
Mahadzir Ishak
Keyword(s):  
Intermetallic Compound ◽  
Surface Finish ◽  
Electroless Nickel ◽  
Optical Microscope ◽  
Compound Formation ◽  
Intermetallic Compound Growth ◽  
Surface Finishes ◽  
Intermetallic Compound Formation ◽  
Free Solder ◽  
Immersion Tin

The formation and growth of the intermetallic were frequently discussed since lead free solder took place replacing the lead solder. However, the effect of multiple reflow process on the intermetallic morphology that was subjected to aging still needs further investigation. Thus, this study aimed to investigate the effect of second reflow towards the intermetallic compound formation and growth. Two types of surface finishes were used such as Immersion Tin (ImSn) and Electroless Nickel Immersion Gold (ENIG). Both test boards were reflowed once with Sn-3Ag-0.5Cu at the temperature of 225 °C and soaking for 8 seconds. Then, they were reflowed again at the same temperature for 25 minutes prior to an isothermal aging process for 250, 500, 1000 and 2000 hours at the temperature of 150 °C. The ProgRes C3 IM7200 Optical Microscope and ImageJ were used for the microstructural study, which includes morphology and thickness. Results indicated that IMC thickness formed between solder and ImSn surface finish increased significantly with 1.28 µm incremental when exposed to the second reflow. Whereas the IMC thickness of ENIG surface finish was increased for up to 0.15 µm. In addition, ENIG showed higher activation energy as compared to ImSn.

Intermetallic compound growth between Sn-Cu-Cr lead-free solder and Cu substrate

2019 ◽  
Vol 99 ◽  
pp. 62-73 ◽  
Author(s):  
Junghwan Bang ◽  
Dong-Yurl Yu ◽  
Yong-Ho Ko ◽  
Jun-Hyuk Son ◽  
Hiroshi Nishikawa ◽  
...  
Keyword(s):  
Intermetallic Compound ◽  
Lead Free ◽  
Lead Free Solder ◽  
Cu Substrate ◽  
Intermetallic Compound Growth ◽  
Free Solder
Sign in / Sign up

Export Citation Format

Share Document