Contact Reliability of Innovative Compliant Interconnects for Next Generation Electronic Packaging

Author(s):  
Lunyu Ma ◽  
Qi Zhu ◽  
Suresh K. Sitaraman

The ongoing research work at Georgia Institute of Technology, PARC, Inc., and Nanonexus, Inc. funded by NIST/ATP, aims to develop a novel compliant interconnect technology based on stress-engineering of thin-film metal deposition. The minimum pitch size can reach as small as 6 μm. The fabrication of the stress-engineered compliant interconnect is compatible with the standard IC fabrication processes. Therefore, the compliant interconnect fabrication can be fully integrated into front-end semiconductor process. Also, thousands of interconnects can be fabricated on the wafer in one batch, which can greatly reduce the cost, improve the yield, and facilitate wafer level packaging (WLP). Based on the mechanical advantage of the stress-engineered compliant interconnect, a non-soldering assembly process has been developed. In the non-soldering assembly process, compliant interconnects are pressed against the bonding pads to establish the electrical connection. Test vehicles with such non-soldering contact interconnect have been assembled and subjected to thermal cycling. Although the assembled test vehicles have shown reliability over 1000 cycles, the primary mode of failure occurs at the contact interface between the compliant interconnect tip and the bonding pad. This contact interface is studied using analytical and numerical models to understand the reliability of freestanding sliding-contact compliant interconnect assembly.

Author(s):  
Lunyu Ma ◽  
Qi Zhu ◽  
Suresh K. Sitaraman

The integrated circuit (IC) fabrication technology continues to push the limits of microelectronics packaging technologies. Today millions of transistors can be fabricated in a chip of about 1 cm × 1 cm in size, and the required I/O density is about 1600/cm2. Although tremendous advances have been made in die to substrate interconnect technologies as well as substrate/PWB technologies, these advances have not kept pace with advances in semiconductor technology, and therefore, continue to be a bottleneck for further advances in semiconductor technologies. In addition to fabrication constraints, low cost and reliability are other requirements that affect interconnect development. Wafer-level Packaging (WLP) is an effective solution to address some of these issues. A compliant interconnect, called “J-Spring”, has been proposed and developed at Georgia Institute of Technology. Although based on the same concept of inherent stress-gradient used in the linear spring, the J-Spring will provide greater in-plane compliance. These compliant interconnects can be fabricated in batch at wafer level and the pitch can be as low as 30 μm. The fine pitch can meet and exceed the requirements of International Technology Roadmap for Semiconductor (ITRS) for 2011 [ITRS, 2001] and beyond. J-Springs with different radius, angle, width, and release length have been fabricated on a test wafer. Numerical model has been created to determine the release height based on J-Spring geometry and stress gradients. Also, the compliance of J-Spring has been determined in three orthogonal directions using parametric numerical models. The compliance of J-Spring is compared with the compliance of the linear spring. The proposed compliant interconnects can accommodate the differential displacement due to CTE mismatch between the die and the substrate. In addition, to their mechanical characteristics, their electrical characteristics have been studied as well. The electrical characteristics are dependent on the geometry, dimensions and the materials used.


Author(s):  
Terence Kane

Abstract A 300mm wafer atomic force prober (AFP) has been installed into IBM’s manufacturing line to enable rapid, nondestructive electrical identification of defects. Prior to this tool many of these defects could not detected until weeks or months later. Moving failure analysis to the FAB provides a means of complementing existing FAB inspection and defect review tools as well as providing independent, non-destructive electrical measurements at an early point in the manufacturing cycle [1] Once the wafer sites are non destructively AFP characterized, the wafer is returned to its front opening unified pod (FOUP) carrier and may be reintroduced into the manufacturing line without disruption for further inspection or processing. Whole wafer atomic force probe electrical characterization has been applied to 32nm, 28nm, 20nm and 14nm node technologies. In this paper we explore the cost benefits of performing non-destructive AFP measurements on whole wafers. We have found the methodology of employing a whole wafer AFP tool complements existing in-line manufacturing monitoring tools such as brightfield/dark field optical inspection, SEM in-line inspection and in-line E-beam voltage contrast inspection (EBI).


2000 ◽  
Vol 151 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Stephan Wild-Eck ◽  
Willi Zimmermann

Two large-scale surveys looking at attitudes towards forests, forestry and forest policy in the second half ofthe nineties have been carried out. This work was done on behalf of the Swiss Confederation by the Chair of Forest Policy and Forest Economics of the Federal Institute of Technology (ETH) in Zurich. Not only did the two studies use very different methods, but the results also varied greatly as far as infrastructure and basic conditions were concerned. One of the main differences between the two studies was the fact that the first dealt only with mountainous areas, whereas the second was carried out on the whole Swiss population. The results of the studies reflect these differences:each produced its own specific findings. Where the same (or similar) questions were asked, the answers highlight not only how the attitudes of those questioned differ, but also views that they hold in common. Both surveys showed positive attitudes towards forests in general, as well as a deep-seated appreciation ofthe forest as a recreational area, and a positive approach to tending. Detailed results of the two surveys will be available in the near future.


Author(s):  
Pankaj Musyuni ◽  
Geeta Aggarwal ◽  
Manju Nagpal ◽  
Ramesh K. Goyal

Background: Protecting intellectual property rights are important and particularly pertinent for inventions which are an outcome of rigorous research and development. While the grant of patents is subject to establishing novelty and inventive step, it further indicates the technological development and helpful for researchers working in the same technical domain. The aim of the present research work is to map the existing work through analysis of patent literature, in the field of Coronaviruses (CoV), particularly COVID-19 (2019-nCoV). CoV is a large family of viruses known to cause illness in human and animals, particularly known for causing respiratory infections as evidenced in earlier times such as in MERS i.e. Middle East Respiratory Syndrome; SRS i.e. Severe Acute Respiratory Syndrome. A recently identified novel-coronavirus has known as COVID-19 which has currently caused pandemic situation across the globe. Objective: To expand analysis of patents related to CoV and 2019-nCoV. Evaluation has been conducted by patenting trends of particular strains of identified CoV diseases by present legal status, main concerned countries via earliest priority years and its assignee types and inventors of identified relevant patents. We analyzed the global patent documents to check the scope of claims along with focuses and trends of the published patent documents for the entire CoV family including 2019- nCoV through the present landscape. Methods: To extract the results, Derwent Innovation database is used by a combination of different key-strings. Approximately 3800 patents were obtained and further scrutinized and analyzed. The present write-up also discusses the recent progress of patent applications in a period of the year 2010 to 2020 (present) along with the recent developments in India for the treatment options for CoV and 2019-nCoV. Results: Present analysis showed that key areas of the inventions have been focused on vaccines and diagnostic kits apart from the composition for treatment of CoV. We also observed that no specific vaccine treatments is available for treatment of 2019-nCov, however, developing novel chemical or biological drugs and kits for early diagnosis, prevention and disease management is the primarily governing topic among the patented inventions. The present study also indicates potential research opportunities for the future, particularly to combat 2019-nCoV. Conclusion: The present paper analyzes the existing patents in the field of Coronaviruses and 2019-nCoV and suggests a way forward for the effective contribution in this upcoming research area. From the trend analysis, it was observed an increase in filing of the overall trend of patent families for a period of 2010 to the current year. This multifaceted analysis of identified patent literature provides an understanding of the focuses on present ongoing research and grey area in terms of the trends of technological innovations in disease management in patients with CoV and 2019-nCoV. Further, the findings and outcome of the present study offer insights for the proposed research and innovation opportunities and provide actionable information in order to facilitate policymakers, academia, research driven institutes and also investors to make better decisions regarding programmed steps for research and development for the diagnosis, treatment and taking preventive measures for CoV and 2019-nCoV. The present article also emphasizes on the need for future development and the role of academia and collaboration with industry for speedy research with a rationale.


Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 515
Author(s):  
Thomas Freudenmann ◽  
Hans-Joachim Gehrmann ◽  
Krasimir Aleksandrov ◽  
Mohanad El-Haji ◽  
Dieter Stapf

This paper describes a procedure and an IT product that combine numerical models, expert knowledge, and data-based models through artificial intelligence (AI)-based hybrid models to enable the integrated control, optimization, and monitoring of processes and plants. The working principle of the hybrid model is demonstrated by NOx reduction through guided oscillating combustion at the pulverized fuel boiler pilot incineration plant at the Institute for Technical Chemistry, Karlsruhe Institute of Technology. The presented example refers to coal firing, but the approach can be easily applied to any other type of nitrogen-containing solid fuel. The need for a reduction in operation and maintenance costs for biomass-fired plants is huge, especially in the frame of emission reductions and, in the case of Germany, the potential loss of funding as a result of the Renewable Energy Law (Erneuerbare-Energien-Gesetz) for plants older than 20 years. Other social aspects, such as the departure of experienced personnel may be another reason for the increasing demand for data mining and the use of artificial intelligence (AI).


Author(s):  
Pierangelo Duo´ ◽  
Christian Pianka ◽  
Andrej Golowin ◽  
Matthias Fueller ◽  
Roger Schaefer ◽  
...  

During operating service, gas turbine aero-engines can ingest small hard particles which typically produce damage to the aerofoils. If the damage found is a tear or a perforation at the leading edge, it is known as a Foreign Object Damage or FOD and this leads to a reduction of the subsequent High-Cycle-Fatigue (HCF) strength. The objective of research work in this area is to assess the effect of FOD on the residual fatigue strength of compressor blades and to provide predictive tools for engineering judgment. The methodology followed is normally to carry out experimental simulation of FOD, followed by fatigue tests to assess subsequent performance. To date, research related to fatigue following FOD events has concentrated on HCF loading and the impact geometry is frequently that of a sphere against a flat surface or the edge of a blade-like specimen. Both of these aspects do not correspond to the worst cases of real FOD. Here it is intended to investigate the effect of a V-notch geometry, which is more representative of severe FOD found in service. Alongside this, numerical models can be used to simulate the damage and to evaluate the residual stress field. In addition analytical model are used to predict the residual fatigue strength. The current work explains the development of a new rig impact test and discusses the improvements necessary to obtain a sufficient repeatability of the impacts. From the experience gained with a gas gun, an alternative method using a pistol and a barrel, capable of achieving the necessary velocity of simulated FOD, was developed. The applied velocity was in the range of 250m/s to 300m/s and a technique to describe the impact is here discussed. Furthermore the introduction of a high speed camera has allowed to have a complete description of the impact scene and to better understand the impact. The impacted blades were measured and HCF tested. As a result, this has produced a large scatter in the residual fatigue strength. The current method to describe a notch using a 2D approach, which was applied to several geometries of notches, is here critically reviewed. The proposed method would incorporate a more sophisticated method, which reconstruct the real geometry using optical measurement. This latter measurement can fully describe the 3D geometry, showing particularly zones inside the notch where compressive residual might appears. Tears and shear of the material can also be described by applying this technique. The findings are compared with the residual HCF strength and the results are compared to special cases of HCF to justify the results out of theoretical prediction.


2018 ◽  
Vol 25 (4) ◽  
pp. 962-968 ◽  
Author(s):  
Frederic Compin

Purpose The purpose of this paper is to analyse how terrorism financing can be assimilated with money launderning when the amounts ofmoney involved differ so markedly. Not only is the cost of financing terrorist attacks minimal compared to the huge sums often at stake in financial crimes, but also the psychological profile of terrorists, who are reclusive by nature, contrasts starkly with that of financial criminals, who are usually fully integrated members of society. When terrorism financing is equated with money laundering this represents a utilitarian approach in that it facilitates the creation of a security strategy and stifles criticism of criminogenic capitalismthat turns a blind eye to tax evasion. Design/methodology/approach The analysis is conceptual, focussing on the assimilation of terrorism financing with money laundering. There is an interview with a French magistrate, specialized in the fight against corruption and white-collar crime, and data have been collected from international organizations and scholarly articles. Findings The fight against money laundering and money dirtying has clearly sparked numerous controversies around evaluation, scope, criminal perpetrators and a lack of vital cooperation between administrative and judicial services. Social implications This paper raises questions about the reasons behind the linking of money laundering and money dirtying by states and players in public international law and why the fight against money laundering is very much overshadowed by their focus on terrorist financing in dealing with the growing threat of Islamic State, otherwise known as ISIS or ISIL, in the Middle East and West Africa. Originality/value The paper enables the reader to raise the question of similarities between the fight against money laundering and the fight against terrorism financing.


2018 ◽  
Vol 90 (5) ◽  
pp. 858-868 ◽  
Author(s):  
Muhammad Taimoor ◽  
Li Aijun ◽  
Rooh ul Amin ◽  
Hongshi Lu

Purpose The purpose of this paper is to design linear quadratic regulator (LQR) based Luenberger observer for the estimation of unknown states of aircraft. Design/methodology/approach In this paper, the LQR-based Luenberger observer is deliberated for autonomous level flight of unmanned aerial vehicle (UAV) which has been attained productively. Various modes like phugoid and roll modes are exploited for controlling the rates of UAV. The Luenberger observer is exploited for estimation of the mysterious states of the system. The rates of roll, yaw and pitch are used as an input to the observer, while the remaining states such as velocities and angles have been anticipated. The main advantage of using Luenberger observer was to reduce the cost of the system which has been achieved lucratively. The Luenberger observer proposes sturdiness at the rate of completion to conquest over the turmoil and insecurities to overcome the privileged recital. The FlightGear simulator is exploited for the endorsement of the recital of the Luenberger observer-based autopilot. The level flight has been subjugated lucratively and has been legitimated by exploiting the FlightGear simulator. The authenticated and the validated results are offered in this paper. Microsoft Visual Studio has been engaged as a medium between the MATLAB and FlightGear Simulator. Findings The suggested observer based on LQR ensures the lucrative approximation of the unknown states of the system as well as the successful level flight of the system. The Luenberger observer is used for approximation of states while LQR is used as controller. Originality/value In this research work, not only the estimation of unknown states of both longitudinal and lateral model is made but also the level flight is achieved by using those estimated states and the autopilot is validated by using the FlightGear, while in most of the research work only the estimation is made of only longitudinal or lateral model.


Author(s):  
Marco A. P. Rosas ◽  
Ana Paula F. Souza ◽  
Marcos V. Rodrigues ◽  
Danilo Machado L. da Silva

In this paper the behavior and the relationship between hydrostatic collapse pressure and diametrically opposed radial compressive force for pipelines were analyzed. This study presents an introduction of a research work aimed to assess the pipeline collapse pressure based on the radial collapse force. Initially the hydrostatic collapse pressure is analyzed, for pipes with different diameter to wall thickness ratio (D/t) and ovalities, using classical assessment (DNV method) and numerical models (FE). Then, the compressive radial force is also analyzed using numerical models validated by a small-scale ring specimen test. After that, the relationship between hydrostatic collapse pressure and compressive radial force is discussed. These first results show that the radial force is a quadratic function of the collapse pressure.


Author(s):  
Munzer S. Y. Ebaid ◽  
Mohamad Y. Mustafa

The design of the fuel cell plays a major role in determining their cost. It is not only the cost of materials that increases the cost of the fuel cell, but also the manufacturing techniques and the need for skilled technicians for assembling and testing the fuel cell. The work presented in this paper is part of a research work aims to design and manufacture a proton exchange membrane (PEM) modular fuel cell of 100 W output at low cost using conventional materials and production techniques, then testing the fuel cell to validate its performance. This paper will be dealing only with the design of a modular fuel cell that can be mass produced and used to set up a larger fuel cell stack for stationary applications (6 kW) which is capable of powering a medium sized household. The design for 100 W fuel cell module will include the calculations for the main dimensions of the fuel cell components, mass flow rate of reactants, water production, heat output, heat transfer and the cooling system. This work is intended to facilitate material and process selection prior to manufacturing alternatives prior to capital investment for wide-scale production. The authors believe that the paper would lead to a stimulating discussion.


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