2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)最新文献

{"title":"Criteria of unpredictable failure for high-power InGaN LEDs","authors":"A. Chernyakov, A. Kartashova, N. Shmidt, E. Shabunina, N. A. Talnishnikh, A. L. Zakgeim","doi":"10.1109/EUROSIME.2016.7463337","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463337","url":null,"abstract":"The results of the degradation study of commercial InGaN/GaN LEDs with the external quantum efficiency (EQE) ~ 40-50 % at 450-460 nm are presented. It has been clarified that one of the mechanisms responsible for EQE degradation and the unpredictable failure of LEDs is the multiphonon recombination of carriers. The distorted forward branch of I-V characteristics at U <; 2V and the appearance of the SI ~j4 section on the current spectral noise density dependences on current density in LEDs before or after 100 hours of aging test are the criteria identifying an unpredictable failure.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"34 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125963891","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":"Characterization of polyimid-multi-layer thin films combining laser ultrasonic measurements and numerical evaluations","authors":"E. Grunwald, R. Nuster, R. Hammer, H. Asmann, G. Paltauf, R. Brunner","doi":"10.1109/EUROSIME.2016.7463353","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463353","url":null,"abstract":"Modern microelectronic devices frequently require the use of thin films and multi-layer systems [1]. Especially the application of advanced material models to simulate e.g. reliability issues for such components relies on the accurate determination of the layers' elastic properties [2]. Polyimides (PI) show many beneficial mechanical and chemical properties for applications in the field of microelectronics, e.g. in the realization of MEMS packages [3]. In the work reported here, the combination of a laser ultrasonic measurement and a numerically solved theoretical model [4] is presented in order to determine the elastic properties of a multi-layer system. The multi-layer system consists of a polyimide layer of 11 μm thickness and an 800 nm silicon nitride film on a (100) silicon substrate. The theoretical model uses a partial wave ansatz and a global matrix method in order to determine the frequency dependent phase velocity [5]. For the measurement of the frequency dependent phase velocity, nanosecond laser pulses were focused to a line shape onto the sample surface. This line excitation generates plane broadband surface acoustic waves (SAWs). The phase velocity depends on the frequency as a consequence of the different sound velocities of substrate and layers. The low frequency SAWs propagate mainly in the substrate, whereas higher frequency waves propagate mostly in the thin layers. An optical beam deflection method was applied to detect the SAWs. The Young's Modulus and the Poisson ratio of the polyimide layer were derived by fitting the theoretical curve to the experiment. The presented method provides the possibility to measure contactless on wafer level. It represents a valuable tool regarding the non-destructive evaluation of elastic properties of thin films in multi-layered systems. The Young's modulus and the Poisson ratio can serve as essential input for various advanced measurement techniques and simulations [2].","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123349700","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":"Experimental and numerical investigation of fatigue damage development under multiaxial loads in a lead-free Sn-based solder alloy","authors":"B. Métais, M. Kuezynska, A. Kabakchiev, S. Wolfangel, P. Buhl, S. Weihe","doi":"10.1109/EUROSIME.2016.7463378","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463378","url":null,"abstract":"Electronic devices for automotive applications undergo substantial thermo-mechanical cyclic loads during their operation. Within the phase of assembly, a large variety of passive and active electronic components are electrically connected by solder joints of complex geometrical shapes. As a consequence, external thermomechanical loads result in local multiaxial stress states in the solder material during their operation. In the past years, significant efforts were made in the characterization of solder materials and the accurate FE-modeling of their viscoplastic deformation behavior as well as the modeling of their damage behavior. However, material testing and numerical model calibration were focused on uniaxial tests, which result in a homogeneous stress state and a fixed ratio between its hydrostatic and deviatoric parts. Therefore, the correlation between varying multiaxial loads and cyclic damage evolution in solder alloys is still not understood. Here, we report on the experimental investigation of Low Cycle Fatigue (LCF) on bulk samples under uniaxial and multiaxial stress states realized by means of a pure tension-compression and superimposed tension-torsion loads. In order to describe the observed cyclic degradation behavior, a phenomenological fatigue damage model is modified incorporating the influence of multiaxial stresses in the damage development. The new damage model is implemented as a user-subroutine for Finite Element (FE) calculation supported by the commercial FE-package ansysTM. Uniaxial and multiaxial loads are simulated on the meshed specimen-geometry. The material model is able to describe the mechanical properties in the initial state of deformation. Besides, it shows numerical stability which enables the simulation of large number of cyclic loads. Based on the damage mechanic approach enhanced by multiaxial effects, this study contributes to the framework of solder joints modeling.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123534745","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":"Simulation of micro-bump interconnections failure analysis for 2.5D IC packaging","authors":"J. Lan, Mei-Ling Wu","doi":"10.1109/EUROSIME.2016.7463388","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463388","url":null,"abstract":"This paper provides micro-bump fracture analysis in the context of a 2.5D IC package under reflow process. With the increasing demands for product functionality, the pitch size and diameter of micro-bumps have become smaller, as a means of achieving higher input/output counts in microelectronic packages. However, by decreasing micro-bump diameter, integrity of the microelectronic package is becoming compromised. The majority of research on the system in package (SiP) has focused on the Coefficient of Thermal Expansion (CTE) mismatch and heat junctions. The primary problems arising due to CTE mismatch and heat dissipation are failures or fatigues in 2.5D IC package, which can escalate to critical reliability issues. However, thermo-mechanical stress induced by temperature loading has a significant effect on material strength, causing, for example, interfacial cracking or micro-bump failure. Thus, 2.5D IC package modeling needs to be developed in order to identify factors that can mitigate micro-bump failure under reflow process. In this paper, we discuss the different insights pertaining to physics of thermo-mechanical loading for 2.5D IC package.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126526112","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":"Multi-physics simulation of a wind piezoelectric energy harvester validated by experimental results","authors":"G. Acciani, Filomena Di Modugno, E. Mininno, P. Montegiglio","doi":"10.1109/EUROSIME.2016.7463341","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463341","url":null,"abstract":"The growing research interest coming from the wide diffusion of wireless micro sensors and small electronic devices has given input on several studies towards Energy Harvesting (EH) as possible alternative to their powering in untraditional way. In the EH field the use of piezoelectric materials is developing rapidly. In this scenery, the aim of this paper is to evaluate the experimental and simulated behaviour and performances of an energy harvester, with the shape of a piezoelectric cantilever beam, subjected to wind induced-vibrations. The mathematical model is described by the Navier-Stokes equations and the constitutive equations of piezoelectric materials. The experimental setup is simulated using the software Comsol Multiphysics.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126541166","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 new method to model transient multi-material moisture transfer in automotive electronics applications","authors":"Daniel Markus, M. Schmidt, Karin Lunz, U. Becker","doi":"10.1109/EUROSIME.2016.7463322","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463322","url":null,"abstract":"This paper analyzes moisture diffusion methods regarding their applicability under varying boundary conditions and under consideration of non-linear material properties. It is shown that commonly utilized methods are not adequate for a physically consistent treatment of multimaterial setups with non-linear saturation concentrations. In order to overcome this limitation in moisture modeling, a new method, the so called Surface Humidity Potential approach is introduced, verified, and applied to a moisture simulation of a printed circuit board subjected to an environment encountered in automotive applications. Overall, a sound foundation for moisture analysis of plastic materials encountered in electronic components is established.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574854","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":"An in situ tensile test device for thermo-mechanical characterisation of interfaces between carbon nanotubes and metals","authors":"S. Hartmann, J. Bonitz, M. Heggen, S. Hermann, O. Holck, S. Schulz, T. Gessner, B. Wunderle","doi":"10.1109/EUROSIME.2016.7463360","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463360","url":null,"abstract":"In this paper we present our recent efforts to develop an in situ tensile test device for thermo-mechanical characterization of interfaces between single-walled carbon nanotubes (SWCNTs) and metals. For the mechanical tests, the chosen loading condition is a pull-out test. After summarizing results of maximum stresses calculated from molecular dynamics simulations and obtained from in situ scanning electron microscope experiments we outline the requirement for an in situ experimental method with atomic resolution to study the mechanics of SWCNT-metal interfaces in further detail. To this purpose, we designed, fabricated and characterized a silicon-based micromechanical test stage with a thermal actuator for pull-out tests inside a transmission electron microscope. The objective is to obtain in situ images of SWCNT-metal interfaces under mechanical loads at the atomic scale for fundamental structure investigation. The design of this MEMS test stage permits also the integration of SWCNTs by wafer level technologies. First experiments with this MEMS test stage confirmed the presence of suspended thin metal electrodes to embed SWCNTs. These suspended thin metal electrodes are electron transparent at the designated SWCNT locations. Actuator movements were evaluated by digital image correlation and we observed systematic actuator movements that allow for a defined load application of SWCNTS. Although significant image drifts occured during actuation, we achieved atomic resolution of the metal electrode and stable movement in the focal plane of the electron microscope. The presented system may be also used and further developed for in situ characterization of other materials.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128183915","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 optimization of MEMS piezoelectric energy harvester","authors":"D. Hoffmann, T. Bechtold, D. Hohlfeld","doi":"10.1109/EUROSIME.2016.7463403","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463403","url":null,"abstract":"This work presents an optimization strategy towards extending the operational frequency range of piezoelectric MEMS energy harvesting devices. We propose to use coupled micromechanical resonators to enable efficient energy harvesting at multiple frequencies with a single device. The proposed design, obtained by optimization algorithms, exhibits closely spaced eigenfrequencies with equal power delivery.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115817263","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":"Low-cycle fatigue of multilayer metal stack employed as fast wafer level monitor for backend integrity in smart power technologies","authors":"Alexander Mann, H. Lohmeyer, Yvonne Joseph","doi":"10.1109/EUROSIME.2016.7463315","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463315","url":null,"abstract":"A novel approach for wafer-level test and monitoring of multilayer metal-stack integrity in integrated circuit process technology based on the low-cycle fatigue of power device metallization structure is described. Repetitive power pulsing at the limit of the electro-thermal safe-operating area of the devices reveals systematic changes in level and homogeneity of intrinsic thermomechanical robustness and is able to activate latent defects. Exemplarily for two smart-power process technologies the intrinsic low-cycle lifetime limit is explored as reference basis and transfer to test vehicles on product or process control module is validated in experimental case-study and supported by detailed electrothermal simulation of stress pulse events.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"143 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124552081","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 experiments on multilayer ceramic capacitors and fracture mechanics analysis","authors":"J. Al Ahmar, S. Wiese","doi":"10.1109/EUROSIME.2016.7463359","DOIUrl":"https://doi.org/10.1109/EUROSIME.2016.7463359","url":null,"abstract":"This paper presents results of fracture tests on Multilayer Ceramic Capacitors (MLCCs). Fracture mechanical calculations were carried out with ANSYS in order to analyse the experimental values of fracture strength for the tested MLCCs. Subsequent metallographic analyses were used to get a precise picture of the origin and the propagation of the crack through the component.","PeriodicalId":438097,"journal":{"name":"2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122858446","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}