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Physically meaningful and easy-to-use analytical predictive stress models are developed for a through-silicon-via (TSV) design using theory-of-elasticity based approach. Two extreme cases of the TSV height-to-diameter ratios are considered: disc-like vias, with the aspect ratios below 0.25 (plane stress approximation can be employed in this case), and rod-like-vias, with aspect ratios, above 2.5 (plane...
The rapid technological advancements and market demands in electronic sector requires application of highly accelerated, still practice relevant reliability assessment methods. At present, accelerated power and temperature cycling tests count as the state of the art for qualification of the devices. However due to physical characteristics of the devices, there are limitations to accelerated thermal...
Carbon nano-tubes (CNTs) and carbon nano-fibers (CNFs) are characterized by a number of unique and extraordinarily attractive physical/mechanical properties. Examples are high Young’s modulus, high tensile strength, low coefficient of thermal expansion (CTE), and high thermal conductivity. These unique properties of CNTs and CNFs lead to many potentially attractive applications of these quasi-one-dimensional...
Physically meaningful and easy-to-use analytical solutions are obtained, using analytical modeling and theory-of-elasticity approach, for thermal stresses in typical through-silicon-via (TSV) packages of 3D IC devices. The case when the package is heated up from the room temperature to an elevated temperature is considered. Two extreme cases of the TSV geometry are addressed: disc-like vias, with...
The bathtub curve (BTC) can be viewed as an experimental reliability “passport” of a population of mass produced devices. This curve considers and reflects the combined effect of two irreversible processes: statistics-related mass-production process and reliability-physics-related degradation (aging) process. The statistics-related process results in a decreasing failure rate with time. The reliability-physics-related...
The earlier suggested model for the dynamics of element reliability distribution over a generalized strength (capacity) space [2] reflects the roles of both strength deterioration and failure processes. The present model is a modification of the previously suggested model and considers the interaction of the instantaneous stress (demand) with the instantaneous strength (capacity). Modified Smoluchowski's...
There is an obvious incentive for using bow-free (temperature change insensitive) assemblies in aerospace optoelectronics: elevated bow might lead to the reduction or even to the total loss in the coupling efficiency. A bi-material bi-component assembly cannot be made bow-free: the total bending moment is never zero in such an assembly. To become bow-free, an assembly comprised of dissimilar materials...
Viscoplastic finite-element simulation was used to predict reliability of solder joints in a high temperature 4-chips stacked capacitor mounted on a PCB under temperature cycling (−55°C to +125°C, 45min ramps/60min dwells). A three-dimensional (3D) model was built considering the materials properties of a commercial component. Capacitor materials were determined by using scanning electron microscopy...
Aerospace avionics and operation need another dimension. The “glass cockpit” came as a response to an impossible perceptive situation, when pilots had to monitor countless gauges (the concept being “one info-one gauge”). The change came with the renegotiation of the info/surface ratio given to data at the pilot level by using CRTs to integrate data in a user-friendly (dedicated) format. Since then...
Despite all the today's effort, devices and systems that underwent the highly popular highly-accelerated-life-testing (HALT), passed the existing qualification tests (QT) and survived the burn-in testing (BIT), often fail in the field. Are these tests, specifications and practices adequate? If not, could they be improved to an extent that for a product that passed the QT and survived the appropriate...
In this paper, a printed circuit board (PCB) carrying surfacemounted devices (SMD) subjected to impact or vibration loads applied to its support contour is considered. A model-based prognosis approach is employed to assess the remaining useful life (RUL) of the ball-grid-array (BGA) solder joint interconnections. The approach deals with the interaction (coupling) of the “fast” PCB vibration model...
Numerous scenarios have been proposed for a human mission to Mars. The crew size is typically between three and six astronauts. According to experts in human factors, a crew of three is possible but a crew of six is more appropriate. However, it is shown in this paper that the impact of the number of astronauts on the design, the risks, and the cost of the first mission might be much more important...
Some major risks-of-failure issues for the future manned missions to Mars are addressed. The specific complexity of the mission with the necessity of new and important technological developments has considerable implications in terms of risk estimation and management. The latest NASA reference mission is addressed and is commented on. It is concluded that the present design strategies are unable to...
Operation principle and possible applications of a novel type of silicon cell integrated circuit (IC) device - injection-coupled device (ICD) - are addressed, including design-for-reliability (DfR) aspects. Examples of possible ICD electrical and physical designs are examined in detail. These are based on the existing CMOS and use bipolar technologies. It is shown that ICDs are, to an extent, similar...
In our recent publication we have demonstrated that BaTiO3/hyperbranched polyester/methacrylate hybrid nano-particles, with a filler fraction of 41 wt.% first dissolved in 2-butoxyethanol and crosslinked during 3 hours (at 125°C), exhibited highly promising dielectric constant as high as 85 at 1kHz. On the other hand, when the same hybrid nanoparticles have been diluted in methyl methacrylate (MMA)...
The following “ten commandments” for the predicted and quantified reliability of aerospace electronic, and photonic products are addressed and discussed: 1) The best product is the best compromise between the needs for reliability, cost effectiveness and time-to-market; 2) Reliability cannot be low, need not be higher than necessary, but has to be adequate for a particular product; 3) When reliability...
Two advanced probabilistic design-for-reliability (PDfR) concepts are addressed and discussed in application to the prediction, quantification and assurance of the aerospace electronics reliability: 1) Boltzmann-Arrhenius-Zhurkov (BAZ) model, which is an extension of the currently widely used Arrhenius model and, in combination with the exponential law of reliability, enables one to obtain a simple,...
Simple and easy-to-use analytical (mathematical) predictive model has been developed for the assessment of the size of an inelastic zone, if any, in a ball-grid-array (BGA) assembly. The solder material is considered linearly elastic at the strain level below the yield point and ideally plastic above this level. The numerical example carried out for a 30mm long surface-mount package with a 200 micrometer...
A “high level”, deductive-reasoning-based (“holistic”), approach is aimed at the direct analysis of the behavior of a system as a whole, rather than with an attempt to understand the system's behavior by conducting first a “low level”, inductive-reasoning-based, analysis of the behavior and the contributions of the system's elements. The holistic view on treatment is widely accepted in medical practice,...
The next generation of multi-beam satellite systems that would be able to provide effective interactive communication services will have to operate within a highly flexible architecture. One option to develop such flexibility is to employ microwaves and/or optoelectronic components and to make them reliable. The use of optoelectronic devices, equipments and systems will result indeed in significant...
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