A Characterization Study of Flip Chip Ball Grid Array (FCBGA) Dynamic Response and Performance on Peripheral Component Interconnect (PCI) Board Application

Author(s):  
Shaw Fong Wong ◽  
Wei Keat Loh ◽  
Yung Hsiang Lee ◽  
Eng Hooi Yap ◽  
Siang Woen Wong ◽  
...  

This paper outlines and discusses the new mechanical characterization metrology applied on PCI board. The dynamic responses of PCI board were monitored and characterized using accelerometers and strain gauges. PCI board bend modes were analyzed to differentiate high risk areas through analysis of board strain responses to solder joint crack performance. Key influences, such as thermal/mechanical enabling preload masses and profiled shock on solder joint crack severity were also conducted to understand the potential SJR performance risk modulators. Commercial simulation software analysis tool was applied to correlate and predict the board’s bend modes; providing key information for product enabling solutions design. With this new characterization and validation concept, a practical stiffener solution for PCI application was designed to improve board SJR performance in its application condition.

Author(s):  
Kayleen L. E. Helms ◽  
Betty Phillips

A characterization study is undertaken to monitor damage progression at the second-level interconnect in BGA’s on flip-chip electronic packages. Specifically, the progression of solder joint cracking under use conditions (thermal and combined thermomechanical loading) is investigated. The study uses a multi-color dye and peel failure analysis technique to track the initiation and propagation of solder joint cracks under loading. The approach being used differs from conventional failure analysis techniques in that multiple measurements of damage growth are obtained from the same part providing a full damage history. By using multiple dye colors, all crack initiation points, directions of propagation, and surface crack areas are obtainable experimentally. The scope of the study includes investigating the impact of such factors as die size, package size, BGA size, BGA pitch, enabling load, and internal heat spreaders (IHS’s) on the damage history observed. Based on this study, investigation of sequential loading can be pursued to identify directions and design guidelines for improving solder joint reliability of future BGA’s on flip-chip electronic packages.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S278-S279
Author(s):  
Dorottya Nagy-Szakal ◽  
Mara Couto-Rodriguez ◽  
Joseph Barrows ◽  
Heather L Wells ◽  
Marilyne Debieu ◽  
...  

Abstract Background COVID-19 had spread quickly, causing an international public health emergency with an alarming global shortage of COVID-19 diagnostic tests. We developed and clinically validated a next-generation sequencing (NGS)-based target enrichment assay with the COVID-DX Software tailored for the detection, characterization, and surveillance of the SARS-CoV-2 viral genome. Methods The SARS-CoV-2 NGS assay consists of components including library preparation, target enrichment, sequencing, and a COVID-DX Software analysis tool. The NGS library preparation starts with extracted RNA from nasopharyngeal (NP) swabs followed by cDNA synthesis and conversion to Illumina TruSeq-compatible libraries using the Twist Library Preparation Kit via Enzymatic Fragmentation and Unique Dual Indices (UDI). The library is then enriched for SARS-CoV-2 sequences using a panel of dsDNA biotin-labeled probes, specifically designed to target the SARS-CoV-2 genome, then sequenced on an Illumina NextSeq 550 platform. The COVID-DX Software analyzes sequence results and provides a clinically oriented report, including the presence/absence of SARS-CoV-2 for diagnostic use. An additional research use only report describes the assay performance, estimated viral titer, coverage across the viral genome, genetic variants, and phylogenetic analysis. Results The SARS-CoV-2 NGS Assay was validated on 30 positive and 30 negative clinical samples. To measure the sensitivity and specificity of the assay, the positive and negative percent agreement (PPA, NPA) was defined in comparison to an orthogonal EUA RT-PCR assay (PPA [95% CI]: 96.77% [90.56%-100%] and NPA [95% CI]: 100% [100%-100%]). Data reported using our assay defined the limit of detection to be 40 copies/ml using heat-inactivated SARS-CoV-2 viral genome in clinical matrices. In-silico analysis provided >99.9% coverage across the SARS-CoV-2 viral genome and no cross-reactivity with evolutionarily similar respiratory pathogens. Conclusion The SARS-CoV-2 NGS Assay powered by the COVID-DX Software can be used to detect the SARS-CoV-2 virus and provide additional insight into viral titer and genetic variants to track transmission, stratify risk, predict outcome and therapeutic response, and control the spread of infectious disease. Disclosures Dorottya Nagy-Szakal, MD PhD, Biotia (Employee) Mara Couto-Rodriguez, MS, Biotia (Employee) Joseph Barrows, MS, Biotia, Inc. (Employee, Shareholder) Heather L. Wells, MPH, Biotia (Consultant) Marilyne Debieu, PhD, Biotia (Employee) Courteny Hager, BS, Biotia (Employee) Kristin Butcher, MS, Twist Bioscience (Employee) Siyuan Chen, PhD, Twist Bioscience (Employee) Christopher Mason, PhD, Biotia (Board Member, Employee, Shareholder) Niamh B. O’Hara, PhD, Biotia (Board Member, Employee, Shareholder)Twist (Other Financial or Material Support, I am CEO of Biotia and Biotia has business partnership with Twist)


2020 ◽  
Author(s):  
Fangyan Yu ◽  
Ka Wai Leong ◽  
Alexander Makrigiorgos ◽  
Viktor A Adalsteinsson ◽  
Ioannis Ladas ◽  
...  

Abstract Sensitive detection of microsatellite instability (MSI) in tissue or liquid biopsies using next generation sequencing (NGS) has growing prognostic and predictive applications in cancer. However, the complexities of NGS make it cumbersome as compared to established multiplex-PCR detection of MSI. We present a new approach to detect MSI using inter-Alu-PCR followed by targeted NGS, that combines the practical advantages of multiplexed-PCR with the breadth of information provided by NGS. Inter-Alu-PCR employs poly-adenine repeats of variable length present in every Alu element and provides a massively-parallel, rapid approach to capture poly-A-rich genomic fractions within short 80–150bp amplicons generated from adjacent Alu-sequences. A custom-made software analysis tool, MSI-tracer, enables Alu-associated MSI detection from tissue biopsies or MSI-tracing at low-levels in circulating-DNA. MSI-associated indels at somatic-indel frequencies of 0.05–1.5% can be detected depending on the availability of matching normal tissue and the extent of instability. Due to the high Alu copy-number in human genomes, a single inter-Alu-PCR retrieves enough information for identification of MSI-associated-indels from ∼100 pg circulating-DNA, reducing current limits by ∼2-orders of magnitude and equivalent to circulating-DNA obtained from finger-sticks. The combined practical and informational advantages of inter-Alu-PCR make it a powerful tool for identifying tissue-MSI-status or tracing MSI-associated-indels in liquid biopsies.


2014 ◽  
Vol 54 (5) ◽  
pp. 939-944 ◽  
Author(s):  
Ye Tian ◽  
Xi Liu ◽  
Justin Chow ◽  
Yi Ping Wu ◽  
Suresh K. Sitaraman

Author(s):  
Justin F. Harrison ◽  
Ionut Radu ◽  
Alan J. Babcock ◽  
Beth A. Todd

The development of highly advanced computer simulation software packages has enabled design engineers to more effectively integrate safety features into their designs. Designs can be tested long before any physical construction ever begins. This saves money, allowing more extensive testing to be performed, and it also saves time, expediting the process of moving concept to reality. In the automotive industry, such software can be especially useful, since computer simulations can be run over and over again, making it possible to observe the effects of adjusting single variables in dynamic situations. This has opened the door for testing of non-typical occupants. Restraints and safety devices are no longer designed to suit the needs of the average person; they can be tailored to account for all body types, or even for the disabled.


2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Andreas Peters ◽  
Zoltán S. Spakovszky

Due to their inherent noise challenge and potential for significant reductions in fuel burn, counter-rotating propfans (CRPs) are currently being investigated as potential alternatives to high-bypass turbofan engines. This paper introduces an integrated noise and performance assessment methodology for advanced propfan powered aircraft configurations. The approach is based on first principles and combines a coupled aircraft and propulsion system mission and performance analysis tool with 3D unsteady, full-wheel CRP computational fluid dynamics computations and aeroacoustic simulations. Special emphasis is put on computing CRP noise due to interaction tones. The method is capable of dealing with parametric studies and exploring noise reduction technologies. An aircraft performance, weight and balance, and mission analysis was first conducted on a candidate CRP powered aircraft configuration. Guided by data available in the literature, a detailed aerodynamic design of a pusher CRP was carried out. Full-wheel unsteady 3D Reynolds-averaged Navier-Stokes (RANS) simulations were then used to determine the time varying blade surface pressures and unsteady flow features necessary to define the acoustic source terms. A frequency domain approach based on Goldstein’s formulation of the acoustic analogy for moving media and Hanson’s single rotor noise method was extended to counter-rotating configurations. The far field noise predictions were compared to measured data of a similar CRP configuration and demonstrated good agreement between the computed and measured interaction tones. The underlying noise mechanisms have previously been described in literature but, to the authors’ knowledge, this is the first time that the individual contributions of front-rotor wake interaction, aft-rotor upstream influence, hub-endwall secondary flows, and front-rotor tip-vortices to interaction tone noise are dissected and quantified. Based on this investigation, the CRP was redesigned for reduced noise incorporating a clipped rear-rotor and increased rotor-rotor spacing to reduce upstream influence, tip-vortex, and wake interaction effects. Maintaining the thrust and propulsive efficiency at takeoff conditions, the noise was calculated for both designs. At the interaction tone frequencies, the redesigned CRP demonstrated an average reduction of 7.25 dB in mean sound pressure level computed over the forward and aft polar angle arcs. On the engine/aircraft system level, the redesigned CRP demonstrated a reduction of 9.2 dB in effective perceived noise (EPNdB) and 8.6 EPNdB at the Federal Aviation Regulations (FAR) 36 flyover and sideline observer locations, respectively. The results suggest that advanced open rotor designs can possibly meet Stage 4 noise requirements.


2011 ◽  
Vol 423 ◽  
pp. 26-30
Author(s):  
S. Assif ◽  
M. Agouzoul ◽  
A. El Hami ◽  
O. Bendaou ◽  
Y. Gbati

Increasing demand for smaller consumer electronic devices with multi-function capabilities has driven the packaging architectures trends for the finer-pitch interconnects, thus increasing chances of their failures. A simulation of the Board Level Drop-Test according to JEDEC (Joint Electron Device Council) is performed to evaluate the solder joint reliability under drop impact test. After good insights to the physics of the problem, the results of the numerical analysis on a simple Euler-Bernoulli beam were validated against analytical analysis. Since the simulation has to be performed on ANSYS Mechanical which is an implicit software, two methods were proposed, the acceleration-input and the displacement-input. The results are the same for both methods. Therefore, the simulation is carried on the real standard model construction of the board package level2. Then a new improved model is proposed to satisfy shape regular element and accuracy. All the models are validated to show excellent first level correlation on the dynamic responses of Printed Circuit Board, and second level correlation on solder joint stress. Then a static model useful for quick design analysis and optimization’s works is proposed and validated. Finally, plasticity behavior is introduced on the solder ball and a non-linear analysis is performed.


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