A Model for Intermetallic Growth in Thin Sn Joints Between Cu Substrates: Application to Solder Microjoints

Arafat, Yeasir; Yang, Hanry; Dutta, I.; Patel, Abhay K.; Datta, Biplab

doi:10.1007/s11664-020-08019-8

Cited by 7 publications

(3 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is found that there is saturated state in growth and hardening of IMCs in the system, which is consistent with our results given in figures 7 and 8. Arafat et al [49] also presented a multicomponent diffusion-based model and confirmed that the intermetallic-growth rate becomes slow at the end of an aging process in the solder joints. By modeling temperature dependency and chemical reaction of intermetallics under thermal cycling, Morozov et al [50] suggested that the growth mechanism is originated from the multi-component diffusion in solids and affected by the residual stresses and strains in the joint zone.…”

Section: Detailed Microstructural/mechanical Characterizationmentioning

confidence: 84%

Expectation–maximization machine learning model for micromechanical evaluation of thermally-cycled solder joints in a semiconductor

Chen

2023

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

This paper aims to study the microstructural and micromechanical variations of solder joints in a semiconductor under the evolution of thermal-cycling loading. For this purpose, a model was developed on the basis of expectation-maximization machine learning (ML) and nanoindentation mapping. Using this model, it is possible to predict and interpret the microstructural features of solder joints through the micromechanical variations (i.e. elastic modulus) of interconnection. According to the results, the classification of Sn-based matrix, intermetallic compounds and the grain boundaries with specified elastic-modulus ranges was successfully performed through the ML model. However, it was detected some overestimations in regression process when the interfacial regions got thickened in the microstructure. The ML outcomes also revealed that the thermal-cycling evolution was accompanied with stiffening and growth of intermetallic compounds; while the spatial portion of Sn-based matrix decreased in the microstructure. It was also figured out that the stiffness gradient becomes intensified in the treated samples, which is consistent with this fact that the thermal cycling increases the mechanical mismatch between the matrix and the intermetallic compounds.

show abstract

Section: Detailed Microstructural/mechanical Characterizationmentioning

confidence: 84%

Expectation–maximization machine learning model for micromechanical evaluation of thermally-cycled solder joints in a semiconductor

Chen

2023

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Arafat et al ( 2020 ) have modeled intermetallic growth between Cu and Sn aged at different temperatures. It is supposed that the much slower growth rate of the interfacial IMCs in the aged solder joints at temperatures lower than 373 K, and especially of Cu 3 Sn, is mainly related to the substantially slower diffusion of Cu atoms to the IMC growth fronts at these temperatures.…”

Section: Resultsmentioning

confidence: 99%

Hybrid solder joints: the effect of nanosized ZrO2 particles on morphology of as-reflowed and thermally aged Sn–3.5Ag solder joints

et al. 2023

View full text Add to dashboard Cite

The main number of current researches has been focused on the microstructure and mechanical properties of the Sn-based Sn–Ag–Cu-based solders, while various kinds of nanosized particles have been added. The synthesis and handling of ceramic nanosized powder are much easier than of metal nanoparticles. In addition, metal nanoparticles solved in solder joints during the soldering process or by thermal aging could behave as an alloying element similar to bulk metal additions, while ceramic nanoparticles retain their chemically inactive behavior in various thermal, thermo-mechanical, and electrical constraints. In some cases, the solved metal nanosized inclusions could increase the growth kinetics of the present intermetallic phases or even create new phases, which leads to more complexity in the predictions and simulations of chemical processes in the solder joints. Based on the assertions mentioned above, ceramic nanosized particles are industrially more favorable as reinforcing inclusions. On the other hand, there is no direct comparison in the literature between Sn-based Sn–Ag–Cu and Sn–Ag solder joints with similar ceramic nanoinclusions based on microstructural features and mechanical properties. In the present research, the Cu/flux + NPs/SAC/flux + NPs/Cu solder joints were produced with a nominal amount of 0.2 wt%, 0.5 wt%, and 1.0 wt% nanosized ZrO2 powder. The solder joints prepared via the above-described method are called in the literature as hybrid solder joints. The microstructure of the as-reflowed and thermally aged samples has been studied, especially at the interface solder/substrate. It has been shown that the minor additions of ZrO2 NPs lead to a decrease in the thickness of the Cu6Sn5 interfacial layer in the as-reflowed solder joints and a reduction in the growth kinetics of this layer, while the Cu3Sn interfacial IMC layer remains practically unaffected. Similar investigations were performed in our previous study but for both the hybrid and nanocomposite Sn–3.0Ag–0.5Cu solder joints. A comparative analysis of the impact of the ZrO2 nanoinclusions on the hybrid solder joints using Sn–3.5Ag and Sn–3.0Ag–0.5Cu has been performed.

show abstract

“…The diameter of micro solder bumps for TSV interconnection is expected to be downsized from the current 100 to future 1 μm (Zhang et al , 2018; Jung et al , 2019; Tu, 2011), which will significantly affect the interfacial reaction (Tu et al , 2013). Cu and Ni films are the most common under bump metallization (UBMs), so the asymmetric Cu/Solder/Ni solder joint has been a standard interconnection structure in current packaging structures (Lee et al , 2017; Yu et al , 2019; Baek et al , 2021; Arafat et al , 2020). However, as the size of the solder joints continues to decrease, interfacial reaction at the Cu/Solder and Ni/Solder interfaces would interact simultaneously (Dong et al , 2017a), i.e.…”

Section: Introductionmentioning

confidence: 99%

Effect of reflow temperature and solder size on Cu-Ni cross-interaction in the Cu/Sn/Ni micro solder joints

Gao

Zhang

Wei

et al. 2023

View full text Add to dashboard Cite

Purpose Solder bumps for chip interconnections are downsizing from current approximately 100 µm to the expected 1 µm in future. As a result, the Cu-Ni cross-interaction in Cu/Solder/Ni solder joints will be more complicated and then strongly influence the growth of the intermetallic compounds (IMCs). Thus, it is critical to understand the fundamental aspects of interfacial reaction in micro solder joints. This paper aims to reveal the effect mechanism of reflow temperature and solder size on the interfacial reaction in Cu/Solder/Ni solder joints. Design/methodology/approach The Cu-Ni cross-interaction in the Cu/Sn/Ni micro solder joints with 50 and 100 µm solder sizes at 250°C and 300°C were observed, respectively. The line-type interconnects were soaked in silicone oil, and the temperature of the line-type interconnects was 250 ± 3°C and 300 ± 3°C, which were monitored by a fine K-type thermocouple, and followed by an isothermal aging process at various times. After aging, the specimens were removed from the silicone oil and cooled in the air to room temperature. Findings The major interfacial reaction product on both interfaces was (Cu,Ni)6Sn5, and the asymmetric growth of (Cu,Ni)6Sn5, evidenced by the thickness of (Cu,Ni)6Sn5 IMCs at the Sn/Ni interface was always larger than that at the Sn/Cu interface, resulted from the directional migration of Cu atoms toward the Sn/Ni interface under Cu concentration gradient. The morphology of (Cu,Ni)6Sn5 IMC at Sn/Cu interface was columnlike at 250°C, and which changed from columnlike to scallop with large aspect ratio at 300°C, while that at Sn/Ni interface gradually evolved from needlelike to the mixture of needlelike and layered at 250°C, and which evolved from needlelike to scallop with large aspect ratio at 300°C. The evolution of morphology of (Cu,Ni)6Sn5 is attributed to the content of Ni. Furthermore, the results indicate that the Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints. Originality/value The asymmetric growth of (Cu,Ni)6Sn5 in the Cu/Sn/Ni micro solder joints, evidenced by the thickness of (Cu,Ni)6Sn5 IMCs at the Sn/Ni interface, was always larger than that at the Sn/Cu interface. The morphology evolution of (Cu,Ni)6Sn5 IMC at both interfaces was attributed to the content of Ni. The Cu-Ni cross-interaction was stronger with small solder size and relatively low temperature in the Cu/Sn/Ni micro solder joints.

show abstract

A Model for Intermetallic Growth in Thin Sn Joints Between Cu Substrates: Application to Solder Microjoints

Cited by 7 publications

References 33 publications

Expectation–maximization machine learning model for micromechanical evaluation of thermally-cycled solder joints in a semiconductor

Expectation–maximization machine learning model for micromechanical evaluation of thermally-cycled solder joints in a semiconductor

Hybrid solder joints: the effect of nanosized ZrO2 particles on morphology of as-reflowed and thermally aged Sn–3.5Ag solder joints

Effect of reflow temperature and solder size on Cu-Ni cross-interaction in the Cu/Sn/Ni micro solder joints

Contact Info

Product

Resources

About