Low-temperature creep of SnPb and SnAgCu solder alloys and reliability prediction in electronic packaging modules

doi:10.1016/j.scriptamat.2012.12.017

Scripta Materialia

Volume 68, Issue 8, April 2013, Pages 607-610

https://doi.org/10.1016/j.scriptamat.2012.12.017 Get rights and content

Creep tests covering a broad temperature range (−40 to 120 °C) were systematically performed on Pb5Sn and Sn3Ag0.5Cu solder alloys. Experimental results showed that both solder alloys creep significantly within the temperatures and stress levels tested. A single set of constitutive equations was constructed to describe creep deformation over a wide range of stress and temperature. Numerical analyses revealed that, when evaluating creep failure, significant errors may result from ignoring creep at low temperatures, especially for the lead-free solder alloy Sn3Ag0.5Cu.

References (17)

C. Kanchanomai et al.
Scripta Mater.
(2004)
M. McLean
Acta Metall.
(1985)
S. Wiese et al.
Sens. Actuators A Phys.
(2002)
S. Wiese et al.
Microelectron. Reliab.
(2004)
J. Zhao et al.
Int. J. Fatigue
(2000)
K.S. Kim et al.
Microelectron. Reliab.
(2003)
J. Cadek
Creep in Metallic Materials
(1988)
H. Ma et al.
J. Mater. Sci.
(2009)

There are more references available in the full text version of this article.

Cited by (52)

Effects of Ni-decorated reduced graphene oxide nanosheets on the microstructural evolution and mechanical properties of Sn-3.0Ag-0.5Cu composite solders
2022, Intermetallics
Introducing foreign reinforcements into solder joints has been demonstrated to be beneficial to promoting the soldering reliability. In this work, Ni-decorated reduced graphene oxide (Ni-RGO) nanosheets as foreign reinforcements were prepared through the in-situ thermal decomposition of Ni-glycolate@RGO complexes. xNi-RGO/SAC305 composite solders (x = 0, 0.01, 0.03, 0.05, 0.07, 0.1 wt%) were fabricated by the powder metallurgy method. The results showed that Ni nanoparticles were finely and evenly anchored on both sides of RGO nanosheets. The grain size in xNi-RGO/SAC305 composite solders was significantly refined, while the thickness of the interfacial intermetallic compounds (IMCs) decreased with increasing of Ni-RGO content. The average tensile strength of Cu/(Ni-RGO/SAC305)/Cu solder joints reached 43.0 MPa (18.1% higher than that of the plain SAC305 solder joints) when the amount of Ni-RGO addition reached 0.03 wt%, in which the crack initiation formed occurred in the soldering seam zone. The crack initiated in the micropores between the copper parent metal and composite solder when the content of Ni-RGO nanosheets was above 0.05 wt%, which may due to the agglomerating of submicron-sized Ni-RGO at the interface. These results suggest that traces of Ni-RGO nanosheets (0.03 wt%) can efficiently improve the interfacial bonding strength and solderability of the Cu/(Ni-RGO/SAC305)/Cu solder joint.
Thermal fatigue reliability improvement of leadless ceramic chip carrier solder joints
2022, Microelectronics Reliability
Citation Excerpt :
However, Sn63Pb37 solder is still used in many high-reliability industries [22,23]. There are also many studies comparing the properties of SnPb solder and Sn-Ag-Cu solder [24–26]. Some studies indicate that Sn-Ag-Cu solder has better material properties than SnPb solder [27,28].
In order to improve the thermal fatigue reliability of LCCC (Leadless Ceramic Chip Carrier) solder joints, the assembly process and failure mechanism of LCCC devices are analyzed. It is concluded that the solder joints height is the main factor to improve its thermal fatigue reliability. Reliability qualification tests are performed to contrast the improvement effect of several methods. The Sn10Pb90 column mounting specimen can greatly improve the fatigue reliability and can adapt to most environmental requirements. Some significant conclusions are drawn by comparing the tests results of different specimens. The method can also be used for the other package types to improve the reliability.
Shear performance of microscale ball grid array structure Cu(Ni)/Sn–3.0Ag–0.5Cu/Cu(Ni) solder joints at low temperatures
2022, Materials Today Communications
In this study, the shear performance of microscale ball grid array structure Cu/Sn–3.0Ag–0.5Cu (SAC305)/Cu, Cu/SAC305/Ni, Ni/SAC305/Cu, and Ni/SAC305/Ni solder joints was investigated at decreasing temperatures (25 °C, 0 °C, −25 °C, −50 °C, −75 °C, −100 °C, and −125 °C). The results showed that the shear performance of the solder joints was considerably influenced by both the temperature and substrate materials. The shear strength of the Cu/SAC305/Cu solder joint monotonically increased with decreasing temperature, whereas the shear strength first increased and then decreased for the other solder joints. The fracture positions of all solder joints shifted from the solder matrix to the interface between the solder matrix and intermetallic compound layer when the temperature decreased, and the fracture mechanism changed from ductile to brittle with a ductile-to-brittle transition temperature of approximately −75 °C. Moreover, the interfacial fracture of the Cu/SAC305/Ni and Ni/SAC305/Cu solder joints was prone to occur at the Ni substrate side.
Effect of indentation depth and strain rate on mechanical properties of Sn0.3Ag0.7Cu
2022, Microelectronics Reliability
In this paper, nanoindentation tests with continuous stiffness measurement (CSM) technique were conducted on Sn0.3Ag0.7Cu (SAC0307) at room temperature. The mechanical properties and creep behavior of SAC0307 under different indentation depths and strain rate were studied. Results show that SAC0307 alloy has good plastic deformation ability and the contact stiffness increases linearly with the depth of the indentation. Under different indentation depths and strain rates, the hardness of the material will be affected by the indentation size effect (ISE). Moreover, the hardness shows a certain strain rate sensitivity under the action of different strain rates. The elastic modulus of the material is almost constant with the increase of the indentation depth during the indentation process. But at lower indentation depth (h_max = 500 nm), the elastic modulus-displacement curve fluctuates greatly due to ISE affect. Based on the Nix-Gao model, the hardness (H₀) of SAC0307 is 0.2GPa, and the micro characteristic length h^⁎ is 867 nm. For the same holding time, creep deformation is more evident under high strain rate and indentation depths. The creep strain rate decrease with the increase of holding time and tends to a constant value.
Thermomechanical properties and fatigue life evaluation of SnAgCu solder joints for microelectronic power module application
2020, Journal of Materials Research and Technology
Citation Excerpt :
Consequently, the life prediction models, based on the accumulated creep strain and the accumulated creep strain energy density, were proposed and implemented [22,23]. However, till now none of the individual constitutive formulations can be successfully applied to cover all types of solder materials which have to serve a broad range of temperature and stress, especially at the sub-0 °C temperatures [24,25]. A complete constitutive relationship covering a larger possible temperature range is highly desirable.
In this paper, a new constitutive model of SnAgCu lead-free solder, which covered the low-temperature and elevated-temperature creep properties, was constructed according to the thermomechanical property test under a wide range of temperatures (−40 to 120 °C). This model was then implemented to the finite element model for simulation of the cyclic creep deformation of Sn3Ag0.5Cu solder in a chip inside the microelectronic power module (MPM). The accumulated creep strain of the solder layer was calculated and used to predict the thermo-mechanical fatigue life of the MPM. The applicability of the life prediction method was evaluated through a cross-check of the present results with that obtained by a double power model in the literature, as well as the thermo-mechanical fatigue test results. It was found that the thermo-mechanical fatigue lives, estimated by the accumulated creep strain and creep strain energy density from the established hyperbolic sine power law, are closer to the test results than that estimated by the double power law. The presented model can be seen as an improvement on the existing constitutive models of SnAgCu lead-free solder.
Growth behaviors of intermetallic compounds on the Sn-0.7Cu-10Bi-xCo/Co interface during multiple reflow
2019, Materials and Design
The Sn-0.7Cu-10Bi-xCo/Co (SCB-xCo/Co) interface reaction during soldering process, and the growth and evolution of intermetallic compounds (IMCs) after multiple reflow were investigated. The experimental results indicated that the IMCs layer was successively delaminated, dissolved and aggregated during multiple reflow, and the IMCs layer was thickened with increasing reflow cycles. The results further showed that the IMCs layers of SCB/Co and SCB-0.20Co/Co interfaces were 11.19 μm and 26.27 μm thick respectively after one reflow. The scallop-shape and flat-shape IMCs layers were generated on the SCB/Co and SCB-0.20Co/Co interfaces during initial reflow. The scallop-shape IMCs layer was transformed into the flat-shape one with increasing reflow cycles on the SCB/Co interface. Co in the solder played a role of purification, and it could decrease the concentration gradient of Co atom on the IMCs/solder interface to inhibit the Co-containing compounds growth. The IMCs were stratified due to reduction of Co concentration on the SCB/Co and SCB-0.20Co/Co interfaces after reflows, respectively. With the increase of reflow cycles, the decrease of Co concentration on the interface caused IMCs obviously to be dissolved into the liquid solder, and the free-state compounds particles were reassembled and grew up under the effect of the adsorption force.

View all citing articles on Scopus

View full text

Low-temperature creep of SnPb and SnAgCu solder alloys and reliability prediction in electronic packaging modules

Scripta Mater.

Acta Metall.

Sens. Actuators A Phys.

Microelectron. Reliab.

Int. J. Fatigue

Microelectron. Reliab.

Creep in Metallic Materials

J. Mater. Sci.