Integrated design method for flip chip CSP with electrical, thermal and thermo-mechanical qualifications

Liu, De‐Shin; Ni, Ching-Yu; Chen, Ching-Yang

doi:10.1016/s0168-874x(02)00133-6

Cited by 10 publications

(5 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 Equivalent residual stresses in package Fig. 5 Equivalent residual stresses in solders after cooling from 453°K to 298°K and substrate (same conditions as in Fig. 4) (cooling rate 0.2°K/s) From the graph of the development of the equivalent stress with temperature in point A in Figure 5 (Fig.…”

Section: Resultsmentioning

confidence: 99%

Analysis of Stress Distribution in SnAgCu Solder Joint

Gong

Liu

Conway

et al. 2006

AMM

View full text Add to dashboard Cite

SnAgCu solder is a promising lead-free material for interconnections in electronic packages. However, its melting temperature (490°K) is considerably higher than that of the traditional SnPb solder (456°K). At the same time, SnAgCu has much better creep resistance at high temperature. These properties may cause large residual stresses during manufacturing processes due to the mismatch of thermal properties of electronic components that can influence the reliability of solder joints in electronic packages. This paper studies the residual stresses in solder joints in a flip chip package under different cooling conditions and their influence on the subsequent cyclic test by means of a finite element approach. The results show that the initial temperature of 453°K is high enough to induce residual stresses due to manufacturing procedures. Simulations, based on traditional creep-fatigue models, demonstrate that the residual stresses affect the mechanical behaviour of solder joints in several initial thermal cycles but have little effect on their reliability.

show abstract

Section: Resultsmentioning

confidence: 99%

Analysis of Stress Distribution in SnAgCu Solder Joint

Gong

Liu

Conway

et al. 2006

AMM

View full text Add to dashboard Cite

show abstract

“…Therefore, in practice, it is necessary to obtain an acceptable compromise between the two design objectives. In this current research, this is achieved by coupling the genetic algorithm (GA) with the FE model (Liu et al 2003) of the P-CMUT in order to determine the optimal value of the geometrical design parameters. A schematic of complete design consideration is shown in Fig.…”

Section: Ga Optimization Design Of the P-cmutmentioning

confidence: 99%

Finite element modeling, characterization, and optimization design for the polymer-typed capacitive micro-arrayed ultrasonic transducer

et al. 2008

View full text Add to dashboard Cite

This study constructs a two-dimensional axisymmetric finite element model (FEM) of the polymertyped capacitive micromachined ultrasonic transducers (P-CMUT). The electromechanical FE model is created using the APDL programming technique. The ANSYS multiphysics solver with sequential approach and the Physics environment files are applied for the solution of the electrostatic-structural coupled-field analysis. Simulations are performed to investigate the operational characteristics, such as collapse voltage and the resonant frequency of the P-CMUT. The numerical results are found to be in good agreement with experimental observation. Having confirmed validity and accuracy of the proposed numerical model, the study of influence of each defined parameter on the collapse voltage and resonant frequency of the P-CMUT are also presented. To solve some conflict problems taken place in diverse physical fields, an integrated multi-objective design method involving electrical and mechanical characterization is developed to optimize the geometric parameters and material properties of the P-CMUT. The optimization search routine conducted using the genetic algorithm (GA) is connected with the commercial FEM software ANSYS to obtain the best design variable using multi-objective functions. The results show that the optimal parameter values satisfy the conflicting objectives of the design procedures, namely to minimize the collapse voltage while simultaneously maintaining a high resonant frequency. Overall, the presented results confirm that the combined FEM/GA optimization approach provides an efficient and versatile means for optimization design of the P-CMUT.

show abstract

“…These studies only consider the thermal aspect and, in some ways, the micro-mechanical aspects, as contact resistance is found by contact pressure and deformation of the asperities. Even when a thermomechanical coupling is considered for the calculation of the mechanical deformation and pressure in order to determine the thermal contact resistance, the contact pressure is still considered to be uniformly distributed over the surface [11] or not considered at all [12]. When tackling the problem at a macroscopic level, considering the contact pressure as evenly distributed over the surface would be a risky assumption.…”

Section: Introductionmentioning

confidence: 99%

“…Even when a thermo-mechanical coupling is considered for the calculation of the mechanical deformation and pressure in order to determine the thermal contact resistance, the contact pressure is still considered to be uniformly distributed over the surface 11 or not considered at all. 12 When tackling the problem at a macroscopic level, considering the contact pressure as evenly distributed over the surface would be a risky assumption. This would be far from reality because the distribution of this pressure is very variable, 13 becoming zero in the areas where the contact is lost, and such areas can represent the majority of the interface in some assemblies.…”

Section: Introductionmentioning

confidence: 99%

Use of 1D mechanical and thermal models to predetermine the heat transferable by a thermal interface material layer in space applications

Vandevelde

Daidié

Sartor

2020

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

This paper proposes the use of 1D basic models to build a design assistance tool capable of evaluating the heat transfer between a third-level electronic packaging and its support, considering a conventional configuration where a thermal interface material is placed between these two parts. Using this kind of tool early in the design process may facilitate choices concerning geometry and material. The packaging is modelled by a stepped beam (the equipment) and the interface layer by a nonlinear elastic foundation (the thermal interface material). Considering that the electronic equipment bends under the effect of the forces exerted by the fasteners, the tool makes it possible to determine the contact zone remaining operative after deformation, and the pressure distribution at the interface. Mechanical results are then used to calculate the steady-state heat transfer between the equipment and its support, taking into account the diffusion within the equipment and the thermal interface material, and also the thermal contact resistances, the latter being dependent on the contact pressure. A detailed case study is used to illustrate the utility of the approach. The 1D models are exploited to illustrate the interest of the design assistance tool. The influence of different parameters on the thermal performance is studied and a new innovative proposal is analyzed, which could lead to a significant increase in thermal performance.

show abstract

Integrated design method for flip chip CSP with electrical, thermal and thermo-mechanical qualifications

Cited by 10 publications

References 14 publications

Analysis of Stress Distribution in SnAgCu Solder Joint

Analysis of Stress Distribution in SnAgCu Solder Joint

Finite element modeling, characterization, and optimization design for the polymer-typed capacitive micro-arrayed ultrasonic transducer

Use of 1D mechanical and thermal models to predetermine the heat transferable by a thermal interface material layer in space applications

Contact Info

Product

Resources

About