Accelerative reliability tests for Sn3.0Ag0.5Cu solder joints under thermal cycling coupling with current stressing

AbstractThrough ultrasonic wave assisted Sn2.5Ag0.7Cu0.1RExNi/Cu (x = 0, 0.05, 0.1) soldering test and − 40 to 125 °C thermal shock test, the microstructure and shear properties of Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints under thermal cycling were studied by the SEM, EDS and XRD. The results show that the Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints with high quality and high reliability can be obtained by ultrasonic assistance. When the ultrasonic vibration power is 88 W, the ultrasonic-assisted Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu solder joints exhibits the optimized performance. During the thermal cycling process, the shear strength of ultrasonic-assisted Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints had a linear relationship with the thickness of interfacial intermetallic compound (IMC). Under the thermal cycling, the interfacial IMC layer of ultrasonic-assisted Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints consisted of (Cu,Ni)6Sn5 and Cu3Sn. The thickness of interfacial IMC of ultrasonic-assisted Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints was linearly related to the square root of equivalent time. The growth of interfacial IMC of ultrasonic-assisted Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints had an incubation period, and the growth of IMC was slow within 300 cycles. And after 300 cycles, the IMC grew rapidly, the granular IMC began to merge, and the thickness and roughness of IMC increased obviously, which led to a sharp decrease in the shear strength of the solder joints. The 0.05 wt% Ni could inhibit the excessive growth of IMC, improve the shear strength of solder joints and improve the reliability of solder joints. The fracture mechanism of ultrasonic-assisted Sn2.5Ag0.7Cu0.1RExNi/Cu solder joints changed from the ductile–brittle mixed fracture in the solder/IMC transition zone to the brittle fracture in the interfacial IMC.

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Study on the Reliability of Sn–Bi Composite Solder Pastes with Thermosetting Epoxy under Thermal Cycling and Humidity Treatment

Crystals ◽

10.3390/cryst11070733 ◽

2021 ◽

Vol 11 (7) ◽

pp. 733

Author(s):

Lu Liu ◽

Songbai Xue ◽

Ruiyang Ni ◽

Peng Zhang ◽

Jie Wu

Keyword(s):

Solder Joint ◽

Thermal Cycling ◽

Composite Solder ◽

Solder Joints ◽

Solder Paste ◽

Epoxy System ◽

Mechanical Reinforcement ◽

Microstructure Observation ◽

Temperature And Humidity ◽

Thermosetting Epoxy

In this study, a Sn–Bi composite solder paste with thermosetting epoxy (TSEP Sn–Bi) was prepared by mixing Sn–Bi solder powder, flux, and epoxy system. The melting characteristics of the Sn–Bi solder alloy and the curing reaction of the epoxy system were measured by differential scanning calorimeter (DSC). A reflow profile was optimized based on the Sn–Bi reflow profile, and the Organic Solderability Preservative (OSP) Cu pad mounted 0603 chip resistor was chosen to reflow soldering and to prepare samples of the corresponding joint. The high temperature and humidity reliability of the solder joints at 85 °C/85% RH (Relative Humidity) for 1000 h and the thermal cycle reliability of the solder joints from −40 °C to 125 °C for 1000 cycles were investigated. Compared to the Sn–Bi solder joint, the TSEP Sn–Bi solder joints had increased reliability. The microstructure observation shows that the epoxy resin curing process did not affect the transformation of the microstructure. The shear force of the TSEP Sn–Bi solder joints after 1000 cycles of thermal cycling test was 1.23–1.35 times higher than the Sn–Bi solder joint and after 1000 h of temperature and humidity tests was 1.14–1.27 times higher than the Sn–Bi solder joint. The fracture analysis indicated that the cured cover layer could still have a mechanical reinforcement to the TSEP Sn–Bi solder joints after these reliability tests.

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Effects of Current Stressing on Shear Properties of Sn-3.8Ag-0.7Cu Solder Joints

Journal of Material Science and Technology ◽

10.1016/s1005-0302(10)60116-8 ◽

2010 ◽

Vol 26 (8) ◽

pp. 737-742 ◽

Cited By ~ 11

Author(s):

X.J. Wang ◽

Q.L. Zeng ◽

Q.S. Zhu ◽

Z.G. Wang ◽

J.K. Shang

Keyword(s):

Solder Joints ◽

Shear Properties ◽

Current Stressing

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The Influence of Metal Plating of Chip Carriers on Reliability of SMT Solder Joints under Thermal Cycling

Soldering & Surface Mount Technology ◽

10.1108/eb037836 ◽

1993 ◽

Vol 5 (3) ◽

pp. 18-20

Author(s):

J.H. Huang ◽

H.Z. Li

Keyword(s):

Thermal Cycling ◽

Solder Joints ◽

Metal Plating

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A Highly Accelerated Thermal Cycling (HATC) Test for Solder Reliability Assessment in BGA Packages

ASME 2007 InterPACK Conference, Volume 1 ◽

10.1115/ipack2007-33271 ◽

2007 ◽

Cited By ~ 1

Author(s):

X. Long ◽

I. Dutta ◽

R. Guduru ◽

R. Prasanna ◽

M. Pacheco

Keyword(s):

Thermal Cycling ◽

Solder Joints ◽

Low Cycle Fatigue ◽

Inelastic Strain ◽

Fatigue Reliability ◽

Element Analysis ◽

Mechanical Cycling ◽

Experimental Apparatus ◽

Dependent Strain ◽

Accelerated Thermal Cycling

A thermo-mechanical loading system, which can superimpose a temperature and location dependent strain on solder joints, is proposed in order to conduct highly accelerated thermal-mechanical cycling (HATC) tests to assess thermal fatigue reliability of Ball Grid Array (BGA) solder joints in microelectronics packages. The application of this temperature and position dependent strain produces generally similar loading modes (shear and tension) encountered by BGA solder joints during service, but substantially enhances the inelastic strain accumulated during thermal cycling over the same temperature range as conventional ATC (accelerated thermal cycling) tests, thereby leading to a substantial acceleration of low-cycle fatigue damage. Finite element analysis was conducted to aid the design of experimental apparatus and to predict the fatigue life of solder joints in HATC testing. Detailed analysis of the loading locations required to produce failure at the appropriate joint (next to the die-edge ball) under the appropriate tension/shear stress partition are presented. The simulations showed that the proposed HATC test constitutes a valid methodology for further accelerating conventional ATC tests. An experimental apparatus, capable of applying the requisite loads to a BGA package was constructed, and experiments were conducted under both HATC and ATC conditions. It is shown that HATC proffers much reduced cycling times compared to ATC.

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Mechanisms of thermal cycling damage in polycrystalline Sn-rich solder joints

Materials Science and Engineering A ◽

10.1016/j.msea.2019.138614 ◽

2020 ◽

Vol 771 ◽

pp. 138614 ◽

Cited By ~ 2

Author(s):

Marion Branch Kelly ◽

Antony Kirubanandham ◽

Nikhilesh Chawla

Keyword(s):

Thermal Cycling ◽

Solder Joints

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Prediction of mechanical properties and fatigue life of nano silver paste in chip interconnection

10.21203/rs.2.23255/v1 ◽

2020 ◽

Author(s):

Hui YANG ◽

Jihui Wu

Keyword(s):

Fatigue Life ◽

Solder Joint ◽

Thermal Cycling ◽

Solder Joints ◽

Stress And Strain ◽

Nano Silver ◽

Finite Element Software ◽

Flip Chips ◽

Empirical Correction ◽

Prediction Of Mechanical Properties

Abstract The simulation of nano-silver solder joints in flip-chips is performed by the finite element software ANSYS, and the stress-strain distribution results of the solder joints are displayed. In this simulation, the solder joints use Anand viscoplastic constitutive model, which can reasonably simulate the stress and strain of solder joints under thermal cycling load. At the same time this model has been embedded in ANSYS software, so it is more convenient to use. The final simulation results show that the areas where the maximum stresses and strains occur at the solder joints are mostly distributed in the contact areas between the solder joints and the copper pillars and at the solder joints. During the entire thermal cycling load process, the area where the maximum change in stress and strain occurs is always at the solder joint, and when the temperature changes, the temperature at the solder joint changes significantly. Based on comprehensive analysis, the relevant empirical correction calculation equation is used to calculate and predict the thermal fatigue life of nano-silver solder joints. The analysis results provide a reference for the application of nano-silver solder in the electronic packaging industry.

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