Study of Thermal Cycle Induced CPI Failure Mode in a Lidded FC-BGA Package

Author(s):  
Muhammad Monzur Morshed ◽  
Esther Chen ◽  
Anita Madan

Abstract Dissimilarities of thermal expansion coefficient between chip and package materials results in stress and strain at the solder interconnect leading to fatigue failures. Underfill is used between chip and package to reduce the interfacial stress and hence increase reliability. In this work, four flipchip package test vehicles underwent thermal cycling to accelerate the stress and were investigated systematically with different failure analysis techniques to study their failure modes. The prevalent failure mode was observed to be at the corner area between the chip and package using different advanced failure analysis techniques. This work demonstrates the technical complexity of analyzing stress induced defects and provides insight into CPI-based material selection.

Author(s):  
I. Österreicher ◽  
S. Eckl ◽  
B. Tippelt ◽  
S. Döring ◽  
R. Prang ◽  
...  

Abstract Depending on the field of application the ICs have to meet requirements that differ strongly from product to product, although they may be manufactured with similar technologies. In this paper a study of a failure mode is presented that occurs on chips which have passed all functional tests. Small differences in current consumption depending on the state of an applied pattern (delta Iddq measurement) are analyzed, although these differences are clearly within the usual specs. The challenge to apply the existing failure analysis techniques to these new fail modes is explained. The complete analysis flow from electrical test and Global Failure Localization to visualization is shown. The failure is localized by means of photon emission microscopy, further analyzed by Atomic Force Probing, and then visualized by SEM and TEM imaging.


Author(s):  
Todd Castello ◽  
Dan Rooney ◽  
Dongkai Shangguan

Abstract Printed circuit board assembly with lead free solder is now a reality for most global electronics manufacturers. Extensive research and development has been conducted to bring lead free assembly processes to a demonstrated proficiency. Failure analysis has been an integral part of this effort and will continue to be needed to solve problems in volume production. Many failure analysis techniques can be directly applied to study lead free solder interconnects, while others may require some modification in order to provide adequate analysis results. In this paper, several of the most commonly applied techniques for solder joint failure analysis will be reviewed, including visual inspection, x-ray radiography, mechanical strength testing, dye & pry, metallography, and microscopy/photomicrography, comparing their application to lead bearing and lead free solder interconnects. Common failure modes and mechanisms will be described with examples specific to lead free solders, following PCB assembly as well as after accelerated reliability tests.


Author(s):  
Cha-Ming Shen ◽  
Tsan-Chen Chuang ◽  
Chen-May Huang ◽  
Shi-Chen Lin ◽  
Jie-Fei Chang

Abstract With the evolution of advanced process technology, failure analysis has become more and more difficult because more defects are of the non-visual type (very tiny or even invisible defects) from new failure mechanisms. In this article, a novel and effective methodology which couples the conductive atomic force microscope (C-AFM) with nano-probing technique is proposed to reveal some particular failure modes which were not observable and difficult to identify with traditional physical failure analysis techniques. The capability of coupling C-AFM with nano-probing technique is used to distinguish cases which suffer general junction leakage or gate leakage from those that form the fake junction leakage or gate leakage cases. C-AFM can detect the abnormal contacts quickly, and nano-probing could provide the precise electrical characteristic further. Then, combining these variant measuring results, the favorable tactics can be adopted to deal with different states.


2005 ◽  
pp. 257-291

Abstract Gears can fail in many different ways, and except for an increase in noise level and vibration, there is often no indication of difficulty until total failure occurs. This chapter begins with the classification of gear failure modes, followed by sections discussing the characteristics of various fatigue failures. Then, it provides information on the modes of impact fractures, wear, scuffing, and stress rupture. Next, the chapter describes the causes of gear failures and discusses the processes involved in conducting the failure analysis. Finally, the chapter presents examples of gear failure analysis.


2021 ◽  
pp. 1-8
Author(s):  
Michael H. Du ◽  
Ke Li ◽  
Fei Song ◽  
Haoming Li ◽  
David L. Smith ◽  
...  

Summary Advanced drill-collar connections have been developed with 10 times extended fatigue life compared with the corresponding replaced connections. More than 4,000 advanced connections have been run in North America. Although these connections have demonstrated substantial fatigue-strength improvement in operation, some failures have occurred. Multiple failed connection samples have been retrieved and analyzed for their failure modes and the root causes. In the failure analyses, manufacturing data were reviewed to identify any possible discrepancies between design specifications and manufactured components. The field run data were analyzed for the loading histories of the connections. The downhole fluid properties were also reviewed to identify their possible effects on the connection performances. The bottomhole assemblies (BHAs) were numerically analyzed to determine the loading distributions. The failed connection samples were physically processed and inspected in a metallurgical laboratory. Based on the combined numerical and testing analyses, the conclusions on the failure modes and the root causes were drawn. It was found that the primary failure mode for these connections was fatigue. The root causes for the fatigue failures can be divided into two categories: manufacturing causes and operational causes. Among the manufacturing failure causes, incorrect cold rolling is the primary one. The operation-related failures were mainly caused by overloading. Through failure mode and root-cause analyses, the manufacturing and operational related risks for the advanced drill-collar connections were mitigated accordingly. It therefore greatly improved the quality assurance of the advanced connections.


2014 ◽  
Vol 13 (06) ◽  
pp. 1229-1257 ◽  
Author(s):  
Kuei-Hu Chang ◽  
Yung-Chia Chang ◽  
Yu-Tsai Lee

Failure mode and effect analysis (FMEA) is one of the risk analysis techniques recommended by international quality certification systems, such as ISO 9000, ISO/TS 16949, CE, and QS9000. Most current FMEA methods use the risk priority number (RPN) value to evaluate the risk of failure. The RPN value is the mathematical product of the three parameters of a failure mode that is rated between 1 and 10 in terms of its severity (S), occurrence (O), and detection (D), respectively. However, the RPN method has been found with three main drawbacks: (1) high duplicate RPN values, (2) failure to consider the ordered weights of S, O, and D, and (3) failure to consider the direct and indirect relationships between the failure modes and causes of failure. Therefore, this paper integrates the technique for order preference by similarity to ideal solution (TOPSIS) and the decision-making trial and evaluation laboratory (DEMATEL) approach to rank the risk of failure. A case of an inlet plate ring that has been drawn from a professional mechanical factory is presented to further illustrate the proposed approach. After comparing the result that was obtained from the proposed method with the conventional RPN and DEMATEL methods, it was found that the proposed method can resolve the abovementioned RPN ranking issues and give a more appropriate risk assessment than other listed approaches to provide valuable information for the decision makers.


2014 ◽  
Vol 926-930 ◽  
pp. 456-461
Author(s):  
Shen Li Chen ◽  
Wen Ming Lee ◽  
Chi Ling Chu

This paper deals with a detailed study of ESD failure mode and how to strengthen of the VDMOS used for power applications. The ESD post-zapped failure of power VDMOS transistors due to HBM, MM, and CDM stresses are examined in this work. Through standard failure analysis techniques by using EMMI and SEM were applied to identify the failure locations. The MM failure mode in this power MOSFET was caused by the gate oxide breakdown near n+ region in the source end as an ESD zapping. And, the ESD failure damage under HBM and CDM stresses were caused by the gate material molten near the gate pad and tunneled through the oxide layer into silicon epitaxial layer. Furthermore, the ESD robustness designs of power VDMOS transistors are also addressed in this work. The first ESD incorporated design is Zener diodes back-to-back clamping the gate-to-source pad, and on the other hand, another one excellent design contains two Zener diodes clamping the gate-to-source and gate-to-drain terminals of a VDMOS, respectively.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Mingfa Ren ◽  
Fei Weng ◽  
Jing Sun ◽  
Zhifeng Zhang ◽  
Zhiguo Ma ◽  
...  

Current pyrotechnic separation devices are mainly made of metal materials, limiting the capacity of lightweight design in advanced launching vehicles. With the outstanding mechanical properties, such as high mass-specific strength and modulus, carbon fiber-reinforced polymers (CFRPs) have the potential to replace metal materials in pyrotechnic seperaton devices. However, to improve the seperation reliability of these pyrotechnic separation devices, there still needs further understanding on the the failure mode of CFRP composites under linear shaped charge (LSC). In this paper, cutting tests were carried out on CFRPs for the failure analysis of CFRPs under LSC, and nonlinear finite element analysis (FEA) was performed to characterize the evolution of LSC cutting in CFRPs. According to experimental simulation and numerical simulation, it can be found that the three main failure modes in CERPs while subjected to LSC jet are shear failure, delamination failure, and tensile failure. In the early cutting stage, the initial time of damage of the fiber and the matrix near the shaped charge shows less difference and the laminate is directly separated by the energy of high-speed jet. When the jet velocity decreases, the jet morphology collapses and matrix damages precede into the fiber, which would cause tensile failure mode of CFRPs. Meanwhile, the delamination in low jet speed stages is larger than that in the high jet speed stages. These studies on the failure modes of CFRPs under LSC provide important basis for the future design of CFRP-based pyrotechnic separation devices, which is important to the lightweight design of launching vehicles.


2005 ◽  
Vol 127 (1) ◽  
pp. 126-137 ◽  
Author(s):  
Y. Park ◽  
J. S. Colton

This paper presents a failure analysis of cylindrical cup drawing dies machined from a polymer composite rapid tooling material. Cup drawing is a complicated process, involving both bending and stretching. In this study, possible die failure modes are identified experimentally. Finite element analyses (FEA) are performed to obtain the stress–strain responses, which are used to determine the dominant failure mode. As cup drawing involves interactions among process parameters, the statistical design of experiments is employed to perform a parametric study. The resulting die failure mode estimation method is verified through experiments.


2021 ◽  
Author(s):  
Michael Hui Du ◽  
Ke Li ◽  
Fei Song ◽  
Haoming Li ◽  
David L. Smith ◽  
...  

Abstract Advanced drill collar connections have been developed with 10 times extended fatigue life compared with the corresponding replaced connections. More than 4,000 advanced connections have been run in North America. Although these connections have demonstrated substantial fatigue strength improvement in operation, some failures have occurred. Multiple failed connection samples have been retrieved and analyzed for their failure modes and the root causes. In the failure analyses, manufacturing data were reviewed to identify any possible discrepancies between design specifications and manufactured components. The field run data were analyzed for the loading histories of the connections. The downhole fluid properties were also reviewed to identify their possible effects on the connection performances. The bottom hole assemblies were numerically analyzed to determine the loading distributions. The failed connection samples were physically processed and inspected in the metallurgical laboratory. Based on the combined numerical and testing analyses, the conclusions on the failure modes and the root causes were drawn. It was found that the primary failure mode for these connections was fatigue. The root causes for the fatigue failures can be divided into two categories: manufacturing causes and operational causes. Among the manufacturing failure causes, incorrect cold rolling is the primary one. The operation related failures were mainly caused by overloading. Through failure mode and root cause analyses, the manufacturing and operational related risks for the advanced drill collar connections were mitigated accordingly. It therefore greatly improved the quality assurance of the advanced connections.


Sign in / Sign up

Export Citation Format

Share Document