2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)最新文献

{"title":"FEM simulation and measurement validation of a cMUT cell","authors":"S. Mao, X. Rottenberg, V. Rochus, B. Nauwelaers, H. Tilmans","doi":"10.1109/EUROSIME.2014.6813847","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813847","url":null,"abstract":"This paper presents Finite Element Modeling (FEM) simulation and experimental results of the acoustic and mechanical behavior of an isolated cMUT cell. cMUT cells fabricated in the SiGeMEMS technology of imec are used as test vehicles. Dynamic characteristics of a cMUT cell actuated by a pulse superimposed on a DC bias, such as resonance frequency, Q-factor and transient displacement, are studied using ANSYS FEM and Polytec vibrometer measurements. A good agreement is achieved between the FEM simulation results and optical measurements. The Rayleigh integral method is used to construct the spatial pressure field based on the transducer surface information obtained both from ANSYS and the optical measurements. The results are compared with hydrophone measurements, and good agreements are achieved. Acoustic measurements on a typical cMUT cell (measuring ~60μm on the side) in a fluorinert medium (FC-84) show a 7MHz center frequency, ~100% -6dB fractional bandwidth (FBW) and several kilo Pascal peak-to-peak pressure at millimeters scale. Our method provides a clear methodology to accurately predict the transient spatial pressure field of a cMUT cell, especially in the far field region, with little time cost.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114188527","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":"Framework to extract cohesive zone parameters using double cantilever beam and four-point bend fracture tests","authors":"S. Raghavan, I. Schmadlak, G. Leal, S. Sitaraman","doi":"10.1109/EUROSIME.2014.6813806","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813806","url":null,"abstract":"This paper focuses on extracting cohesive zone modeling (CZM) parameters for ultra low-k (ULK) interlayer dielectric (ILD) layers present in back end of line stack (BEOL) of flip-chip (FC) semiconductor devices. Unlike other fracture-mechanics based approaches, CZM can simulate crack initiation and propagation at several locations. However, additional parameters need to be determined to enable cohesive zone (CZ) elements to reliably predict the failure region. In this paper, we present a methodology, combing fracture experiments and finite-element (FE) simulations to extract CZM parameters under mixed-mode loading conditions. Using load vs. displacement data from the double cantilever beam (DCB) test and four-point bend test (FPBT) experiments, we have characterized all the parameters necessary for CZM. The developed cohesive zone failure criteria can then be applied to interfaces in BEOL stack models to identify the locations of crack initiation and propagation.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114547846","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":"Effect of laminar air flow on probe burn for spring probe","authors":"B. Zafer, B. Tunaboylu","doi":"10.1109/EUROSIME.2014.6813856","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813856","url":null,"abstract":"This paper investigates transient heat transfer between a heated spring probe and its air environment. A continuum finite volume simulation is used to analyze of heat flow within and from the resistively heated probe to its environment. Experimental results are conducted for spring probe with laminar air flow and without air flow. The numerical results and experimental results are compared and very good agreement is observed.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130302273","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":"Reliability and accelerated test methods for plastic materials in LED-based products","authors":"M. Y. Mehr, W. V. van Driel, G. Zhang","doi":"10.1109/EUROSIME.2014.6813876","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813876","url":null,"abstract":"In this study the effects of thermal ageing on the optical properties of both lens and the remote-phosphor samples, made from Bisphenol-A polycarbonate (BPA-PC) are investigated. The BPA-PC lens and remote phosphor plates are currently widely used in light conversion carriers and optical lenses in LED-based products. Lens and the remote phosphor BPA-PC samples of 3 mm thickness were thermally aged at temperature range 100 to 140 °C. The phosphor plates, combined with a blue LED light source, produce white light with a correlated colour temperature (CCT) of 4000 K. The colour shifting due to thermal ageing was studied by Integrated Sphere. Results show that thermal ageing leads to a significant decrease in the luminous flux and chromatic properties of plates. It is also shown that by increasing the temperature, the kinetics of degradation reaction becomes faster, inferring that lumen depreciation takes place at shorter time. Lumen depreciation up to 30% reduction is extrapolated to temperatures lower than 100 °C. It is shown that the lifetime, defined as 30% lumen depreciation at 40 °C, is around 35 khrs for remote phosphor and around 100 khrs for BPAPC lens. A significant change both in the correlated colour temperature (CCT) and in the chromaticity coordinates (CIE x,y) is also observed in thermally aged specimens. Deterioration of the chromatic properties of the phosphor plates is correlated to the decrease in the luminous flux. Results also confirm the colour shifting of white light towards yellow region. Based on the observed decay of CCT and colour shifting, one could conclude that the thermal degradation of the remote phosphor plates affects both the efficiency and the colour of the LED products. The proposed thermal-ageing qualification method can be used by industries to efficiently select the proper phosphor materials and verify the product design, without many trial-error based interactions.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"181 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124531803","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":"Electronic control package model calibration using moiré interferometry","authors":"Dae-Suk Kim, B. Han, A. Yadur, P. Gromala","doi":"10.1109/EUROSIME.2014.6813835","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813835","url":null,"abstract":"Moiré interferometry is employed to test electronic control units, which are developed for automotive application utilizing transfer molding technology. The control units are subjected to a thermal cycle, and the two orthogonal in-plane displacement fields of the package cross-section are obtained at various temperatures. The results are used to verify and calibrate the complex 3-D finite element model of the units. The detailed experimental procedures including sample preparation are described. The modeling steps that lead to the calibrated finite element model are presented while comparing the experimental results with the numerical predictions.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127791443","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 product based lap shear fatigue testing of electrically conductive adhesives","authors":"B. Öztürk, A. Youssef, P. Gromala, C. Silber, K. Jansen, L. Ernst","doi":"10.1109/EUROSIME.2014.6813767","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813767","url":null,"abstract":"Thermoset-based adhesives are used as thermal and electrical interfaces. These adhesives are filled with different particles in order to meet heat transfer and electrical properties. In automotive applications, they are required to have excellent adhesion since delamination may precipitate other electrical, thermal or mechanical failure mechanisms. A vast amount of literature is available on the investigation of solder die-attach reliability where lap shear experiments are frequently used in microelectronics industry. Both environmental and performance requirements resulted in replacing solder die-attach with lead-free alternatives like electronically conductive adhesives. However, only very few studies so far focus on fundamental understanding of fatigue degradation of these materials. The present paper addresses the above issue. To authors' best knowledge; it is the first time that in lap shear testing of adhesives, the specimens are obtained directly from production line and tested for their fatigue behavior. Authors present a novel, 28 mm long lap shear sample which is made by identical fabrication processes as in the microelectronic component. Thin quad flat packages (TQFP) are inspected with scanning acoustic microscope for possible initial defects right after the production. A cutting process, using a dicing saw, is developed to produce lap shear samples from the packages. The cut samples are investigated by optical and scanning acoustic microscope to improve cutting and test results. Mechanical response of the electrically conductive adhesive is investigated under cyclic loading conditions at 25°C and 100°C for different stress ratios and frequencies. Finally, the stiffness degradation during testing is analyzed and the crosssections of the samples are examined on bulk cracking. The presented method can be used to test different adhesives under production conditions in a fast manner which will decrease product development time and the dependence on time-consuming temperature cycle tests.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127886456","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":"Modeling of SiC power modules with double sided cooling","authors":"K. Brinkfeldt, K. Neumaier, Alexander Mann, Olaf Zschieschang, A. Otto, E. Kaulfersch, Michael Edwards, D. Andersson","doi":"10.1109/EUROSIME.2014.6813864","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813864","url":null,"abstract":"Silicon Carbide (SiC) based transistor devices have demonstrated higher efficiency switching operation compared to silicon-based, state-of-the-art solutions due to the superior electrical and thermal properties of the SiC material. The improved current density and thermal conductivity allows SiC-based power modules to be smaller than their silicon counterparts for comparable current densities. The active chip area can be reduced further by effectively cooling the devices. In this work, a new power module including SiC bipolar junction transistors (BJT) and diodes and integrated double sided cooling will be introduced. The target application of these modules is a new drive-train system for commercial electric vehicles. The double sided cooling concept (named 2Cool) is a feasibility study with the goal to further compact the inverter system. More efficient removal of heat from the junction leads to a higher power rating per die, which in turn leads to fewer die and reduced system volume. Since temperature is a main driver in expected failure modes an increase in cooling capability will also enhance margins of the SiC device reliability. In addition, the removal of wirebonds on the top side of the die will result in lower electrical inductance. Several geometries of the heat exchanger cooling structures have been modeled in terms of thermal performance. The best geometry was a staggered pin-fin structure, which resulted in a junction temperature increase of 74 K at 400 W thermal loading. Also, thermomechanical modeling was used to make an estimation of stress in the power module materials.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"283 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131915812","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":"Limitations and accuracy of steady state technique for thermal characterization of solid and composite materials","authors":"M. AboRas, B. Wunderle, D. May, R. Schacht, T. Winkler, S. Rzepka, B. Michel","doi":"10.1109/EUROSIME.2014.6813766","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813766","url":null,"abstract":"The steady state method is a commonly used and in principle simple way to measure thermal resistance and conductivity of thermal interface materials (TIMs). A heat flow through the TIM has to be generated and the temperature gradient across the TIM has to be measured. This is also defined by the ASTM standard ASTM D5470 [4]. To generate the heat flow the TIM must be positioned between a hot and a cold plate. However, for the new generation of highly conductive and thin TIMs the resolution of the common steady state technique often reaches its limit. To increase the resolution of the steady state equipment beyond the state-of-the- art the test systems must be analyzed and parasitic effects be studied. Accuracy and resolution depend not only on the precision of the setup, but decisively on the selection and execution of the measuring method conformed to the specific measurement task. In this paper we will present a test stand for thermal characterization of TIMs, die attachs and substrates based on the mentioned steady state method. It has been developed as a platform which allows the integration of various modules for characterization of different materials under different conditions, e.g. mated surface, finish, operation temperature, pressure, aging etc.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130771419","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 aspects for CPI robust BEOL","authors":"Mario Gonzalez, L. Kljucar, B. Vandevelde, I. De Wolf, Z. Tokei","doi":"10.1109/EUROSIME.2014.6813824","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813824","url":null,"abstract":"In this paper we present our methodology to establish a quantitative comparison of the induced stresses at different locations of the package and their effect on the strength of the back-end-of-line (BEOL). A Chip Stack Package (CSP) with tight pitch and lead free solder joints is used as test vehicle. Different configurations of the interconnection between the solder balls and the BEOL, including a stiff passivation layer combined with a polyimide stress buffer layer with different thickness and openings are analyzed. It was found that the bending moment of the outermost solder joint induces high tensile stresses in the BEOL layer and this stress is reduced by increasing the thickness of the passivation layer. For this particular case, an optimal geometry of the stress buffer, in terms of thickness and open diameter is proposed. The stresses and energy release rate (ERR) induced on the BEOL is analyzed in a 2 metal layer configuration with different densities of via interconnections. The strength of the BEOL is improved when increasing both, the stiffness of the low-k material and the density of vias.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131021949","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":"Study on configuration design of interconnection in high power module","authors":"L. Liao, T. Hung, Chun-Kai Liu, Yen-Fu Su, K. Chiang","doi":"10.1109/EUROSIME.2014.6813844","DOIUrl":"https://doi.org/10.1109/EUROSIME.2014.6813844","url":null,"abstract":"In a high power module, a high electrical load may cause electromigration and induce the joule heating, subsequently raising the chip temperature. Temperature excursion in the IGBT chip may produce thermal stress, inducing failure in the metal wire and chip. Those failure modes degrade the reliability of a power module. This study elucidates the coupling behavior of a high power module through electro-thermal coupling analysis and thermo-mechanical analysis. Additionally, the configuration design of an aluminum wire is simulated and implemented. Related design parameters, e.g., wire arrangement position, wire number, wire bonding perimeter and wire height, are studied and the design trend of a metal wire is analysed and suggested as well.","PeriodicalId":359430,"journal":{"name":"2014 15th International Conference on Thermal, Mechanical and Mulit-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116919297","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}