The Anti-Vibration Design of the Ball Grid Array Solder Joint

2015 ◽  
Vol 713-715 ◽  
pp. 103-106
Author(s):  
Fan You ◽  
Yong Guang Huang ◽  
Ben Li
Keyword(s):  
Finite Element Method ◽  
Stress Response ◽  
Solder Joint ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Solid Model ◽  
The Finite Element Method ◽  
Lower Height ◽  
Different Diameters ◽  
Vibration Performance

In order to improve the anti-vibration performance of the Ball Grid Array solder joints, its solid model is established in ANSYS. Analyzing the stress response under the shock and vibration environment by using the finite element method. Then discussing the stress response of solder joints with different diameters and different heights in the same shock and vibration environment of each location for providing the basis for anti-vibration design. The results show that the longer diameter and lower height solder joint is more favorable to improve its anti-vibration performance.

Elevated Stand-Off Heights in Solder Joint Interconnections of Surface Mounted IC Packages Result in Appreciable Stress and Warpage Relief

2018 ◽  
Vol 2018 (1) ◽  
pp. 000534-000542
Author(s):  
Ephraim Suhir ◽  
Sung Yi ◽  
Jennie S. Hwang ◽  
R. Ghaffarian
Keyword(s):  
Solder Joint ◽  
Solder Joints ◽  
Calculated Data ◽  
Ball Grid Array ◽  
Substantial Improvement ◽  
Stress Model ◽  
Solder Material ◽  
The Difference ◽  
Free Solder ◽  
Ic Package

Abstract The “head-in-pillow” (HnP) defects in lead-free solder joint interconnections of IC packages with conventional (small) stand-off heights of the solder joints, and particularly in packages with fine pitches, are attributed by many electronic material scientists to the three major causes: 1) attributes of the manufacturing process, 2) solder material properties and 3)design-related issues. The latter are thought to be caused primarily by elevated stresses in the solder material, as well as by the excessive warpage of the PCB-package assembly and particularly to the differences in the thermally induced curvatures of the PCB and the package. In this analysis the stress-and-warpage issue is addressed using an analytical predictive stress model. This model is a modification and an extension of the model developed back in 1980-s by the first author. It is assumed that it is the difference in the post-fabrication deflections of the PCB-package assembly that is the root cause of the solder materials failures and particularly and perhaps the HnP defects. The calculated data based on the developed analytical thermal stress model suggest that the replacement of the conventional ball-grid-array (BGA) designs with designs characterized by elevated stand-off heights of the solder joints could result in significant stress and warpage relief and, hopefully, in a lower propensity of the IC package to HnP defects as well. The general concepts are illustrated by a numerical example, in which the responses to the change in temperature of a conventional design referred to as ball-grid-array (BGA) and a design with solder joints with elevated stand-off heights referred to as column-grid-array (CGA) are compared. The computed data indicated that the effective stress in the solder material is relieved by about 40% and the difference between the maximum deflections of the PCB and the package is reduced by about 60%, when the BGA design is replaced by a CGA system. Although no proof that the use of solder joints with elevated stand-off heights will lessen the package propensity to the HnP defects is provided, the authors think that there is a reason to believe that the application of solder joints with elevated stand-off heights could result in a substantial improvement in the general IC package performance, including, perhaps, its propensity to HnP defects.

A Comparison of Thermal Stress/Strain Behavior of Elliptical/Round Solder Pads

1999 ◽  
Vol 123 (2) ◽  
pp. 127-131 ◽  
Author(s):  
Kuo-Ning Chiang ◽  
Chang-Ming Liu
Keyword(s):  
Thermal Stress ◽  
Solder Joint ◽  
Solder Joints ◽  
Numerical Models ◽  
Ball Grid Array ◽  
Stress Strain ◽  
Restoring Force ◽  
Array Type ◽  
Finite Element Software ◽  
Area Array

As electronic packaging technology moving to the CSP, wafer level packaging, fine pitch BGA (ball grid array) and high density interconnections, the wireability of the PCB/substrate and soldering technology are as important as reliability issues. In this work, a comparison of elliptical/round pads of area array type packages has been studied for soldering, reliability, and wireability requirements. The objective of this research is to develop numerical models for predicting reflow shapes of solder joint under elliptical/round pad boundary conditions and to study the reliability issue of the solder joint. In addition, a three-dimensional solder liquid formation model is developed for predicting the geometry, the restoring force, the wireability, and the reliability of solder joints in an area array type interconnections (e.g., ball grid array, flip chip) under elliptical and round pad configurations. In general, the reliability of the solder joints is highly dependent on the thermal-mechanical behaviors of the solder and the geometry configuration of the solder ball. These reliability factors include standoff height/contact angle of the solder joint, and the geometry layout/material properties of the package. An optimized solder pad design cannot only lead to a good reliability life of the solder joint but also can achieve a better wireability of the substrate. Furthermore, the solder reflow simulation used in this study is based on an energy minimization engine called Surface Evolver and the finite element software ABAQUS is used for thermal stress/strain nonlinear analysis.

The Application of Multi-Wedge Cross Wedge Rolling Forming Long Shaft Technology

2011 ◽  
Vol 101-102 ◽  
pp. 1002-1005 ◽  
Author(s):  
Jing Zhao ◽  
Li Qun Lu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Finite Element Model ◽  
Rolling Mill ◽  
Three Dimensional ◽  
Element Model ◽  
Solid Model ◽  
The Finite Element Method ◽  
Cross Wedge Rolling ◽  
The Finite Element Model

The process of multi-wedge cross wedge rolling is an advanced precision technology for forming long shaft parts such as automobile semi-axes. Three-dimensional solid model and the finite element model of semi-axes on automobile and dies of its cross wedge rolling were established. The process of cross wedge rolling was simulated according to the actual dimension of semi-axes on automobile utilizing the finite element method (FEM)software ANSYS/LS-DYNA. The required force parameters for designing semi-axes mill are determined. The appropriate roller width was determined according to the length and diameter of semi-axes on automobile. The results have provided the basis for the design of specific structure of automobile semi-axes cross wedge rolling mill.

The Optimum Design of A2JK Hoist Drum Based on ANSYS

2011 ◽  
Vol 299-300 ◽  
pp. 1028-1031
Author(s):  
Shuang Chen
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Stress Distribution ◽  
Optimum Design ◽  
Material Properties ◽  
Solid Model ◽  
Finite Element Method Analysis ◽  
The Finite Element Method ◽  
Concrete Condition ◽  
Method Analysis

The hoist drum was analyzed with the finite element method analysis in this article .First, some necessary simplifications of hoist drum were handled and the solid model of reel was made by using of Pro / E. According to the concrete condition, we established material properties, generated the meshing and loads applied as well as other imposed constraints on the rolls based on ANSYS, and finally the hoist drum deformation and stress was solved. By analyzing the results, strain and stress distribution rolls are obtained.

scholarly journals Structural Analysis of a Universal Holding Mechanism for Piston Rings

2001 ◽  
Vol 13 (3) ◽  
pp. 245-253
Author(s):  
Takao Higashimachi ◽  
◽  
Takahide Nakayama ◽  
Takenori Hirakawa ◽  
Hisato Sasahara ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Piston Ring ◽  
Cylinder Block ◽  
The Finite Element Method ◽  
Piston Rings ◽  
Nonlinear Fem ◽  
Simulation Based ◽  
Different Diameters ◽  
Different Parts

By fixing pistons of different diameters with 6 gripping nails, we clarified deformation of piston rings and stress during tightening by simulation based on the finite element method (FEM) as part of development of a universal holding mechanism to insert it into the cylinder block automatically. Nonlinear FEM was used to analyze slidingat contact parts between the ring and the gripping nail when fastening the piston ring. Final defohnation of the piston ring and stress on different parts were verified in detail. We confirmed that insertion of the piston by this method is possible.

Analysis of the Ship Loader's Vibration Mode in the Roll-On Process and the Reinforcement Scheme

2013 ◽  
Vol 721 ◽  
pp. 536-540
Author(s):  
Wen Biao Zhang ◽  
Shu Min Wan ◽  
Bin Lin ◽  
Meng Lai Zhu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Vibration Frequency ◽  
Vibration Mode ◽  
Parametric Modeling ◽  
The Finite Element Method ◽  
Reinforcement Scheme ◽  
Vibration Performance ◽  
Element Method

The roll-on process of the ship loader is studied with the finite element method in this paper. The principle and the scheme of the parametric modeling for the ship loader have been discussed. The vibration frequency and the vibration mode of the ship loader in the roll-on process have been researched, and the weaknesses in the structure of the ship loader have been founded. Based on the above discussion, the reinforcement scheme of the ship loader has been put forward, and the vibration mode and frequency of the strengthened ship loader in the roll-on process have been analyzed. With the comparison of the original one, the anti-vibration performance of the strengthened ship loader has been improved, the reinforcement scheme has been proved to be a worthy one in the roll-on process.

Nonlinear Analysis of Full-Matrix and Perimeter Plastic Ball Grid Array Solder Joints

1997 ◽  
Vol 119 (3) ◽  
pp. 163-170 ◽  
Author(s):  
W. Jung ◽  
J. H. Lau ◽  
Y.-H. Pao
Keyword(s):  
Solder Joint ◽  
Prediction Models ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Reliability Prediction ◽  
Full Matrix ◽  
The Past ◽  
Mask Design ◽  
Plastic Ball ◽  
Joint Deformation

The application of Ball Grid Array (BGA) technology in electronic packaging on high I/O plastic and ceramic packages has grown significantly during the past few years. Although PBGA (plastic BGA) has several advantages over fine-pitch Quad Flat Pack (QFP) in terms of smaller package area, higher I/Os, lower switching noise, large pitch, higher assembly yield, and improved robustness in manufacturing process, potential package reliability problems can still occur, e.g., excessive solder joint deformation induced by substrate warpage, moisture ingression (popcorn effect), large variation in solder ball size, voiding as a result of flux entrapment and improper pad/solder mask design (Marrs and Olachea, 1994; Solberg, 1994; Freyman and Petrucci, 1995; Lau, 1995; Donlin, 1996; Lasky et al., 1996; Munroe et al., 1996). Regardless of its improved thermal fatigue performance over the past few years through an extensive amount of research, the BGA solder joint may still pose a reliability issue under harsh environment, e.g., automotive underhood, larger package size, or higher temperature and temperature gradient due to increase in power dissipation of the package. Numerous studies in BGA solder joint deformation and reliability under thermal and mechanical loadings can be found in the literature, e.g., Borgesen et al. (1993), Choi et al. (1993), Guo et al. (1993), Ju et al. (1994), Lau et al. (1994) Lau (1995), and Heinrich et al. (1995). Also, reliability prediction models have been developed by, e.g., Darveaux et al. (1995) and Darveaux (1996). The present study focuses on the application of a detailed nonlinear finite element analysis (FEA) to studying the thermal cyclic response of solder joints in two particular BGA packages, full-matrix and perimeter. Both time-independent plasticity and time-dependent effect, i.e., creep and relaxation, are considered in the constitutive equations of solder joint to evaluate the discrepancy in the results of life prediction. The critical solder joint is identified, and the locations that are most susceptible to fatigue failure in the critical joint are discussed. Some limitations in computation and reliability prediction are also discussed.

Effects of Ceramic Ball-Grid-Array Package’s Manufacturing Variations on Solder Joint Reliability

1994 ◽  
Vol 116 (4) ◽  
pp. 242-248 ◽  
Author(s):  
Teh-Hua Ju ◽  
Wei Lin ◽  
Y. C. Lee ◽  
Jay J. Liu
Keyword(s):  
Fatigue Life ◽  
Solder Joint ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Printed Wiring Board ◽  
Ceramic Ball ◽  
Solder Volume ◽  
Bga Package ◽  
Reliability Of Solder Joints ◽  
Wiring Board

The effects of manufacturing variations on the reliability of solder joints between a ceramic ball grid array (BGA) package and a printed wiring board (PWB) are investigated. Two cases are studied, namely, with and without spacers between the BGA package and the PWB to maintain the solder joint height. Manufacturing variations considered include changes in solder volume, joint height, and pad size. To evaluate the effect of manufacturing variations on reliability, every possible solder joint profile is first derived. The maximum strain is calculated next. Finally, the fatigue life is predicted. The calculations show that these manufacturing variations change the joint profile, and subsequently affect the fatigue life. Since the package is heavy, the use of spacers is necessary to control the solder joint height for reliable connections, and to maintain a large gap for cleaning. The solder joints formed with the use of spacers, may have convex, cylindrical or concave profiles. The concave solder joints are preferred, since they have long fatigue lives and are less sensitive to the manufacturing variations. For the convex solder joints, their fatigue lives are strongly affected by the joint height variation caused by package warpage and by the combined effects of solder volume and pad size.

scholarly journals Study of Thermal Stress Fluctuations at the Die-Attach Solder Interface Using the Finite Element Method

Electronics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 62
Author(s):  
Luchun Yan ◽  
Jiawen Yao ◽  
Yu Dai ◽  
Shanshan Zhang ◽  
Wangmin Bai ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Thermal Cycling ◽  
Solder Joints ◽  
Stress Recovery ◽  
The Finite Element Method ◽  
Die Attach ◽  
Cyclic Temperature ◽  
Cte Mismatch ◽  
Solder Interface ◽  
Solder Layer

Solder joints in electronic packages are frequently exposed to thermal cycling in both real-life applications and accelerated thermal cycling tests. Cyclic temperature leads the solder joints to be subjected to cyclic mechanical loading and often accelerates the cracking failure of the solder joints. The cause of stress generated in thermal cycling is usually attributed to the coefficients of thermal expansion (CTE) mismatch of the assembly materials. In a die-attach structure consisting of multiple layers of materials, the effect of their CTE mismatch on the thermal stress at a critical location can be very complex. In this study, we investigated the influence of different materials in a die-attach structure on the stress at the chip–solder interface with the finite element method. The die-attach structure included a SiC chip, a SAC solder layer and a DBC substrate. Three models covering different modeling scopes (i.e., model I, chip–solder layer; model II, chip–solder layer and copper layer; and model III, chip–solder layer and DBC substrate) were developed. The 25–150 °C cyclic temperature loading was applied to the die-attach structure, and the change of stress at the chip–solder interface was calculated. The results of model I showed that the chip–solder CTE mismatch, as the only stress source, led to a periodic and monotonic stress change in the temperature cycling. Compared to the stress curve of model I, an extra stress recovery peak appeared in both model II and model III during the ramp-up of temperature. It was demonstrated that the CTE mismatch between the solder and copper layer (or DBC substrate) not only affected the maximum stress at the chip–solder interface, but also caused the stress recovery peak. Thus, the combined effect of assembly materials in the die-attach structure should be considered when exploring the joint thermal stresses.

Sign in / Sign up

Export Citation Format

Share Document