Optimisation of thermo-fatigue reliability of solder joints in surface mount resistor assembly using Taguchi method

The effect of geometric and ambient parameters on static structural integrity of solder joints in surface mount resistor assembled on printed circuit board (PCB) is investigated to improve the thermo-fatigue reliability of the joints and components. The optimisation of resistor thickness (RT) and components standoff height (CSH) in a range of operating homologous temperature (TH) is poised to produce optimal assembly which could accumulate least strain energy density (ωacc) in resistor joints and consequently possesses longer cycles to failure (Nf). Taguchi design of experiment (DOE), L 9 ( 3 3 ) , is used to generate nine designs and finite element modelling (FEM) is employed to simulate the responses of the assemblies to reliability influencing factors (RIFs). The Garofalo-Arrhenius constitutive creep relation is utilised to model high-temperature response of the soldered joints while the concept of signal to noise ratio and statistics are used to determine the optimal design. The results show that settings of lowest RT, highest CSH and TH of 0.86 produce optimal assembly which demonstrates potential of reducing ωacc and increasing Nf of the best design of DOE by 46.9% and 88.3%, respectively. More results show that the nature of finite element model and difference in magnitude of thermal expansion coefficient (CTE) of two bodies bonded together and which experience the same temperature change determine the degree of damage on the interface with the former being more determining.The authors propose the model D M / N ? D N / M = K 1 × K 2 3 { 1 ? D M / N ? D N / M ?s? ∞ 1 ? K 1 × K 2 ?s? ∞ (where: M/N, K1, K2 are isotropic materials, CTE and geometric ratio, respectively) as a quick tool to rank and compare boundary damage in a multi-isotropic-material joining. A combinationbination of DOE and FEM is used to optimise thermo-fatigue reliability in resistor solder joint.Optimised design has thin die thickness and demonstrates low accumulation of damage in its solder joints.A developed mathematical model has potential to identify the most susceptible interconnection boundary in multi-material joining.

[1]  W. Jong,et al.  Comparison of Inelastic Behaviors of Lead-Free and Sn—Pb Solder Joints , 2009 .

[2]  Songbai Xue,et al.  Reliability evaluation of CSP soldered joints based on FEM and Taguchi method , 2010 .

[3]  Jeff Watson,et al.  High-Temperature Electronics Pose Design and Reliability Challenges , 2012 .

[4]  Nduka Nnamdi (Ndy) Ekere,et al.  Damage of lead-free solder joints in flip chip assemblies subjected to high-temperature thermal cycling , 2012 .

[5]  Marc P.Y. Desmulliez,et al.  Optimisation modelling for thermal fatigue reliability of lead‐free interconnects in fine‐pitch flip‐chip packaging , 2009 .

[6]  Emeka H. Amalu,et al.  Evaluation of rheological properties of lead-free solder pastes and their relationship with transfer efficiency during stencil printing process , 2011 .

[7]  Emeka H. Amalu,et al.  Prediction of damage and fatigue life of high-temperature flip chip assembly interconnections at operations , 2012, Microelectron. Reliab..

[8]  Stephen M. Walley,et al.  Mechanical properties of SnPb and lead-free solders at high rates of strain , 2005 .

[9]  Ndy Ekere,et al.  Sub process challenges in ultra fine pitch stencil printing of type‐6 and type‐7 Pb‐free solder pastes for flip chip assembly applications , 2005 .

[10]  E. Davitt,et al.  Effects of thermomechanical cycling on lead and lead-free (SnPb and SnAgCu) surface mount solder joints , 2001, Microelectron. Reliab..

[11]  R. G. Stone,et al.  Mechanical engineering department , 1976 .

[12]  Donggun Lee,et al.  Effect of glue on reliability of flip chip BGA packages under thermal cycling , 2010, Microelectron. Reliab..

[13]  Chris Bailey,et al.  Review of methods to predict solder joint reliability under thermo-mechanical cycling , 2007 .

[14]  R.W. Johnson,et al.  The changing automotive environment: high-temperature electronics , 2004, IEEE Transactions on Electronics Packaging Manufacturing.

[15]  Yang Liu,et al.  Effect of Ni, Bi concentration on the microstructure and shear behavior of low-Ag SAC–Bi–Ni/Cu solder joints , 2014, Journal of Materials Science: Materials in Electronics.

[16]  Li Yang,et al.  Microstructure, interfacial IMC and mechanical properties of Sn–0.7Cu–xAl (x = 0–0.075) lead-free solder alloy , 2015 .

[17]  Michael Pecht,et al.  Thermal Fatigue Reliability Analysis and Structural Optimization Based on a Robust Method for Microelectronics FBGA Packages , 2015, IEEE Transactions on Device and Materials Reliability.

[18]  Ndy Ekere,et al.  PARAMETER INTERACTIONS IN STENCIL PRINTING OF SOLDER PASTE , 1996 .

[19]  M. Pecht,et al.  Warpage Analysis of Flip-Chip PBGA Packages Subject to Thermal Loading , 2009, IEEE Transactions on Device and Materials Reliability.

[20]  Emeka H. Amalu,et al.  High-temperature fatigue life of flip chip lead-free solder joints at varying component stand-off height , 2012, Microelectron. Reliab..

[21]  Emeka H. Amalu,et al.  High temperature reliability of lead-free solder joints in a flip chip assembly , 2012 .