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The purpose of this research is to enhance the structure of the 204-pin small outline dual in-line memory module (SODIMM) against the drop impact. According to the JEDEC regulations, the enhancement of PCB clips should be attempted to increase the resistance against drop impact. From high speed camera observation, the SODIMM module is pushed away from the PCB clips during drop impact. Therefore, the...
In this paper we present a novel approach to determine material thermal properties of thin film materials. As a test case we have chosen silicon nitride employed in a micro-hotplate structure. We use ANSYS to build a three-dimensional finite element (FE) model of the test structure, which considers heat conduction and convection effects. It is further parameterized and subjected to parametric model...
The paper presents extended creep properties of eutectic SnAg3.8Cu0.7 solder using dog bone shaped tensile specimen to extend the data for the Alpha-Omega Model. The tensile test machine was carefully modified with respect of solder material requirements in terms of stress free specimen mounting and assurances of high stable stress conditions. Furthermore the tensile tester is able to measure the...
This study examines the effect of cyclic damage on the constitutive response of Sn3.0Ag0.5Cu (SAC305) solder material. Cyclic damage is induced through isothermal, mechanical cycling tests at high strain rate and room temperature, using a modified lap-shear microscale specimen (180 mum wide solder joint). The elastic, plastic, and yield response of the cycled solder joints are measured as a function...
Moisture induced failures in the plastic encapsulated packages are one most important failure mechanisms in microelectronics. These failures are driven by the mismatch between different material properties, such as CTE, CME (Coefficient of Moisture induced Expansion) and degradation of interface strength caused by moisture absorption of polymer materials. Therefore, it is critical to know how much...
The aim of qualification is to verify whether a product meets or exceeds the reliability and quality requirements of its intended application. Qualification plays an important role in the process of product development. It can be classified by its specific purpose at different stages of the product development process. In this paper, a new methodology of product qualification is proposed based on...
New design for an electro-thermally actuated SU-8 polymeric microgrippers is presented, simulated and analyzed. The electro-thermally driven microgrippers were studied using computer simulations (the Finite Element Method using CoventorWare software tool). Numerical simulations - coupled electro-thermo-mechanical simulations - were performed. We investigated the influence of the temperatures achieved...
In this contribution we present system-level modeling and simulation results for an electrostatic energy harvester with electrically adjustable operation frequency. The device is able to convert mechanical energy present in ambient vibrations into electrical energy. The energy is stored by charging a capacitor and available at constant voltage. The lumped model of the harvester includes the mass-dynamics...
Computational approaches, opportunities and challenges in reduced order modelling based on mode superposition method of the coupled electrostatic-structural domains, including effective model generation and geometrical parameterization, as well as physical and system design of MEMS component are presented and discussed.
The use of monolithic transmission line design allows developing miniature radio frequency (RF) resonators with high sensitivity for nuclear magnetic resonance (NMR) applications. This design has allowed great improvement in NMR micro imaging achieving large signal to noise ratio (SNR) but requires a dedicated tuning technique. We have investigated on a tuning technique based on a dielectric coupling...
In this paper, a leading indicators based approach has been developed for prognostics and health monitoring of electronic systems. The approach focuses on the prefailure space and methodologies for quantification of damage progression and residual life in electronic equipment subjected to shock and vibration loads using the dynamic response of the electronic equipment. Traditional health monitoring...
Calibrated 3-D numerical simulations are employed to quantify the influence of design parameters like emitter area, aspect ratio, distance to trenches, and thickness of AlN heatspreaders on the thermal transient behavior of silicon-on-glass (SOG) bipolar transistors. A larger silicon island enclosed in the trenches reduces the thermal resistance at the expense of a slower thermal response of the system...
Current developments and trends in microelectronics are focused on thin layers and novel materials. This leads to application of different test and measurement methods, which are capable to measure basic mechanical properties of such materials on micro-scale and nano-scale. The presented project focuses on application of the nanoindentation technique in order to extract the basic elastic and elasto-plastic...
We present a simplified model of mechanical behavior of large cantilever arrays with discoupled rows in the dynamic operating regime. Since the supporting bases are assumed to be elastic, cross-talk effect between cantilevers is taken into account. The mathematical derivation combines a thin plate asymptotic theory and the two-scale approximation theory, devoted to strongly heterogeneous periodic...
When assessing the mechanical durability of electronic assemblies, the focus is generally on the solder interconnect. However, in many package styles, such as BGAs (ball grid arrays), LGAs (land grid arrays), MLFs (micro lead frame) and QFNs (quad flat no-lead), the Cu trace emanating from the solder pad may be the weakest failure site, especially if the solder joint is copper-defined rather than...
With the increased complexity of SiP (system in package), Finite Element simulations take an important role in predicting the thermo-mechanical package reliability. Failures in flip chip packages such as die cracking and fatigue of solder bumps are specially the result of the mismatch in thermal expansion coefficients between die and the substrate. In some packages, we use an underfill to improve...
The use of temperature and time dependent material parameters is state-of-the-art in mechanical engineering. An advanced measurement method for the determination of moisture dependent parameters for micro and nano scale samples was developed. In combination with FE-analysis, this tool (involving time, temperature, and humidity) ensures a sure deployability. The present paper deals with the influence...
Reliability of SnAgCu solder joints under mechanical stress is not proven, in particular for Aeronautic and High Performance (AHP) products. They are subjected to high temperatures, severe mechanical stresses and long-term mission profiles. This work is comprehended within a larger study, which has as objective the characterization of the SnAgCu alloys mechanical behaviour at the solder joint scale...
The paper reports the results of a systematic improvement project on the thermal cycle (TC) lifetime prediction of BGA memory modules with SnAg1.0Cu0.5 and SnAg1.0Cu0.5Ni0.05 solder alloys. The pre-existing lifetime modeling scheme allowed predictions with an inaccuracy factor of about 1.6plusmn1 on average while in TC experiments, the characteristic lifetime, N63, showed a standard deviation of about...
This study presents a newly developed dynamic model established by MATLAB Simulink that can handle post pull-in behavior of MEMS electrostatic torsional mirror. In addition to the conventional MATLAB Simulink model of the quadratic oscillation system, a mathematical model of displacement limiter has been inserted to represent the pull-in effect in dynamic analysis. Due to the modification, the model...
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