2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)最新文献

{"title":"Multiphysics modeling and design of ultralarge multiwafer MOVPE reactor for group III-nitride light emitting diodes","authors":"C. Kim, Jongpa Hong, Jihye Shim, Yong-Kwang Won, YongSuk Kwon","doi":"10.1109/ESIME.2010.5464513","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464513","url":null,"abstract":"A multiphysics modeling and design has been performed for the world's largest Metal Organic Vapor Phase Epitaxy (MOVPE) reactor by combining Theory of Inventive Problem Solving (TRIZ) for concept design, Design for Six Sigma (DFSS) for shape optimization, and Computer-Aided Engineering (CAE) simulations of multi-scale from atomic to macro scales. Numerical simulations considering gas phase chemical reactions and surface chemistry have been thoroughly verified by comparing with experimental measurements from various MOVPE reactors. As a preliminary study, two transparent mock-up models for the ultra-large MOVPE reactor were made in real scale and their internal flow fields were measured by laser Doppler velocimetry (LDV). A RF induction heater was also simulated by coupling the thermo-fluid field and electro-magnetic field together. Since the MOVPE reactor was manufactured, numerous tests for high-temperature reliability and temperature uniformity have repeatedly been conducted. Consequently, these multidisciplinary approaches have been successfully applied to develop the ultralarge MOVPE reactor for group III-nitride light emitting diode (LED).","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121194597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical approach to multiscale evaluation and analysis of Tg of crosslinked polymers","authors":"S. Tesarski, O. Holck, A. Wymyslowski","doi":"10.1109/ESIME.2010.5464580","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464580","url":null,"abstract":"Molecular modeling is one of the fastest developing tools in material science. There are a couple of reasons of such a state: on one hand molecular modeling seems to be nowadays much more user friendly and on the other hand is much more efficient in comparison to research based on traditional experiments, which are quite expensive and long lasting. Though the basic problem of numerical analysis is accuracy, in certain cases we can agree with it as long as the predicted tendency or trends are assessed properly. Due to the current state of the art it is justified to formulate the assumption that that results of advanced numerical modeling fulfills expected convergence criteria and correlates well with the experimental data.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132782002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crack and damage in low-k BEoL stacks under assembly and CPI aspects","authors":"J. Auersperg, D. Vogel, M. Lehr, M. Grillberger, B. Michel","doi":"10.1109/ESIME.2010.5464540","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464540","url":null,"abstract":"Miniaturization and increasing functional integration as the electronic industry drives push the development of feature sizes down to the nanometer range. Moreover, harsh operational conditions and new porous or nano-particle filled materials introduced on both chip and package level - low-k and ultra low-k materials in Back-end of line (BEoL) layers of advanced CMOS technologies, in particular - cause new challenges for reliability analysis and prediction. The authors show a combined numerical/experimental approach and results towards optimized fracture and fatigue resistance of those BEoL structures under manufacturing/packaging (during lead-free reflow-soldering, in particular) as well as chip package interaction (CPI) aspects by making use of bulk and interface fracture concepts, in multi-scale and multi-failure modeling approaches with several kinds of failure/fatigue phenomena. Probable crack paths and interactions between material damaging and interface fracture will be investigated and sensitivities with regard to structural modifications studied. Complementary to the simulation side of reliability estimations, serious issues are connected with the collection of appropriate material properties in the miniaturized range addressed - Young's modulus, initial yield stress, hardening. Nano-indentation, AFM, FIB and EBSD provide these desired properties, in particular. In addition, manufacturing induced residual stresses in the Back-end layer stack have an essential impact on damage behavior, because they superpose functional and CPI loads. Their determination with a spatial resolution necessary for typical BEoL structure sizes is a critical issue. The nano-scale stress relief technique (fibDAC) makes use of tiny trenches placed with a focused ion beam (FIB) equipment at the position of stress measurement. Digital image correlation algorithms applied to SEM micrographs captured before and after ion milling allows to conclude on stresses released. Residual stresses can be computed with the help of appropriate, adjusted FEA models.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116214727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanism analyses on PBGA strip packaging warpage","authors":"Yeong-Kook Kim, In Soo Park, Jooho Choi, J. Gang","doi":"10.1109/ESIME.2010.5464527","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464527","url":null,"abstract":"The objective of this study is to analyze warpage development mechanism by simulating a strip type packaging for plastic ball grid array. Molding compound and substrate materials were thermo-mechanically tested to obtain the mechanical properties by several test methods. Samples were fabricated using the same materials, and warpage developments were measured at room temperature after molding compound cure. The results were compared with the measurement data of the samples, and the warpage mechanism was investigated based on the elastic and viscoelastic simulation results. The development mechanism was analyzed through the simulation calculations by combining different material properties modeling and geometries. It was found that the relaxation behaviors of the molding compound and the substrate materials, and the packaging geometry had significant effects on the warpage development. The development mechanism was comprehensively discussed based on the results.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131180924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case study of networked sensors by simulations and experiments","authors":"Cheng Guo, M. Jacobsson, R. V. Prasad","doi":"10.1109/ESIME.2010.5464517","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464517","url":null,"abstract":"In this paper we first introduce sensor networks then we illustrate the problems of performance evaluation in such networks. We compare the two evaluation methods, simulation and experiments. We show how the assumptions and modellings in simulators impact the accuracy of simulation results, with our experience on evaluating flooding protocols in sensor network. We give some suggestions on whether a simulation or an experiment should be carried out while evaluating a sensor network protocol.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131210024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiscale approach optimization on surface wettability change on rough surface","authors":"E. Chan, H. Fan, M. Yuen","doi":"10.1109/ESIME.2010.5464552","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464552","url":null,"abstract":"Surface wettability is known that is not only governed by chemical structure but also by the surface geometrical structure. A multiscale approach on rough surface wettability study was presented in this paper. The wettability study of photo-switched trans and cis isomers of azobenzene on different substrates was first calculated by molecular dynamics calculations. Different chemical structures and configurations were input into the molecular model to get equilibrated structures. Contact angle is then estimated and input into finite element model with roughness factor included. The parameters were input into the FLUENT software to estimate the respective surface wettability for each individual trans and cis configuration on different rough surface. The simulated wettability results were found to be in good correlation with experimental measures. This multiscale approach provides an opportunity to study the combined effects of surface interaction at molecular scale, and micron scale surface roughness, on the wettability of a rough surface. It enables the prediction of contact angle of liquid media on rough surfaces which will be a powerful tool in the selection and optimization of material and substrate surface structure to control the hydrophobicity/hydrophilicity at liquid/solid interface.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124361176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sintering, in different temperatures, of traces of silver printed in flexible surfaces","authors":"R. Mancosu, J. Quintero, R. Azevedo","doi":"10.1109/ESIME.2010.5464510","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464510","url":null,"abstract":"Ink-jet printing is a novel method to promote electrical circuit by printing metal nano-particles onto flexible substrates. A very important part of this process is the sintering of the conductive ink. In this article we used the printer Dimatix DMP-2832, the substrate of polyamide Kapton® and silver nano-particles ink. No surface treatment is used. Isotherms are constructed according to the temperature and time. We can note that higher temperatures do not accelerate the process of sintering. After a certain temperature “ideal” has been achieved we cannot accelerate the process of sintering. This time will remain almost the same.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"330 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122743259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficiency and robustness of some behavior laws in the description of viscoplastic deformation and degradation of solder materials","authors":"S. Msolli, A. Zeanh, O. Dalverny, M. Karama","doi":"10.1109/ESIME.2010.5464600","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464600","url":null,"abstract":"Solder materials are critical packaging compounds and due to usually weakest melting temperature among packaging constitutive materials, thus, they are frequently subjected to a multitude of physical phenomena: creep, fatigue and combined hardening effects. The complexity and interaction of such factors must be considered in suitable way in the mechanical behaviour modelling using the appropriate material behaviour laws. The choice of the mechanical model depends on several factors such as the complexity of constitutive equations to be integrated, the availability and suitability of implementation in the FE codes, the number of parameters to be identified, the capability of the model to represent the most common physical features of the material... Following these observations and in order to deal with this critical remarks, comparisons between the most common unified viscoplastic models should be done in the local and finite element levels for the decision upon the most efficient model. That is the aim of this paper with application to a tin based solder token as the test material.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130664795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large deformation of beam columns - a closed form solution and design guide for vertical buckling probe needles","authors":"T. Hauck, W. Muller","doi":"10.1109/ESIME.2010.5464544","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464544","url":null,"abstract":"Higher pin count and reduced pitch along with increased wafer size set new demands to fine pitch wafer probe technology. Vertical buckling probe needles are one of the available concepts. The required elasticity for contacting the pad is achieved by buckling of the needles. The buckling mode guarantees a consistent contact pressure over a large range of overtravel and thus allows for an optimal tolerance even under changing planarity conditions of the wafer. However, the dimensioning of a buckling needle for specified contact forces seems impossible for designers. Therefore, the authors present closed form solutions for large deformation of buckling beam columns. It is an extension of the Euler buckling cases known from textbooks and goes back to a publication of Thimoshenko regarding the first Euler case. This solution will now be discussed and extended to the fourth Euler case. Its applications will be demonstrated for a vertical buckling probe needle with one end built in and the other end guided by a guide plate. A closed form solution of the force-deflection characteristic will be presented and compared with geometrical nonlinear finite element analysis.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116252825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of Al pad geometry for reducing current crowding effect in flip-chip solder joint using finite-element analysis","authors":"Y. Chang, Chih Chen","doi":"10.1109/ESIME.2010.5464605","DOIUrl":"https://doi.org/10.1109/ESIME.2010.5464605","url":null,"abstract":"Electromigration of flip-chip solder joints has been studied extensively in recent years. It was investigated in plenty of studies that the current crowding effect takes place at the corner near the traces due to huge differences in cross-section area between traces and solder joint. The local high current density, which has been known as a serious reliability issue, causes the failure such as void formation and the consumption under bump metallization (UBM) to occur much earlier than expected in the current-crowding region in solder bump. As a result, to relieve the current crowding effect can significantly increase the mean-time-to-failure (MTTF) of solder bump. On the base of the Blech's equation, the MTTF may be extended to four times of the original value when the local current density is reduced to half of its original one if the n value is taken as 2. Therefore, finding a robust design of geometry, which is effective and of low cost, has turned into a popular issue. However, there is still no technology can observe the current density directly in a current stressed sample. In order to obtain more precise observation, a three-dimensional finite element model (3D-FEM) was performed to simulate the current density distribution in solder bump. In this study, several voids are designed in the Al pad and distributed as concentric circle shape encircling the passivation opening. With these well defined voids, the maximum current density in solder joint is reduced significantly. For flip-chip structure with 1.5µm thick Al pad, the concentric circular voids could reduce the maximum current density in solder joint by more than 60%. The crowding ratio decreases from 4.03 to 1.72. Even if the Al pad is 12µm thick, the concentric circular voids also reduce the maximum current density by about 35%. The crowding ratio decreases from 2.30 to 1.46. The simulation results indicate the design is effective to relieve the current crowding effect and reduce the maximum current density in flip-chip solder joints. To understand how concentric circular voids influence the thermal distribution of flip-chip structure, a thermal-electric multiphysics model is also performed in this study. The thermal-electric simulation results indicate that the concentric circular void also disperse the local Joule heating effect, which comes from the current crowding effect. This approach facilitates the systemic study of optimized design to relieve the current crowding effect and thus increase the electromigration resistance of solder joints. In addition, the results provide a guideline for optimal design for solder joints with a specific UBM structure.","PeriodicalId":152004,"journal":{"name":"2010 11th International Thermal, Mechanical & Multi-Physics Simulation, and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130239853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}