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Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE), 2011 12th International Conference on

Date 18-20 April 2011

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Displaying Results 1 - 25 of 110
  • System-level model of electrothermal microsystem with temperature control circuit

    Publication Year: 2011 , Page(s): 1/5 - 5/5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1040 KB) |  | HTML iconHTML  

    In this paper we demonstrate a system-level simulation of a temperature controlled microsystem which is based on a reduced order model of a micro hotplate. Together with the electro-thermal microstructure we have implemented a control scheme, which allows the hotplate to operate either at a defined setpoint independent of ambient temperature or to follow defined temperature sweeps. An optimization algorithm was employed to identify suitable parameters for a PI-controller. View full abstract»

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  • Cure dependent characterisation of moulding compounds

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1327 KB) |  | HTML iconHTML  

    Curing effects and difference in thermal contraction of components cause residual stresses and warpage during encapsulation of electronic packages. Residual stresses combined with thermal and mechanical loads influence package reliability and performance and may eventually lead to product failure. Comprehensive material characterisation is needed in order to perform numerical simulations which take into account the effect of shrinkage and stress development during the curing reaction of the moulding compound. With that, more reliable predictions can be made. The paper deals with detailed characterisation of moulding compounds. These materials show a clear viscoelastic behaviour, which is both temperature and cure dependent. The performed analyses cover cure kinetics, determination of elongation modulus and the studies on viscoelastic behaviour during cure. Furthermore, dilatometric tests were performed to obtain chemical shrinkage, bulk modulus and to check its time dependency. The obtained parameters including cure shrinkage will be implemented in the finite element software (ANSYS) using user programmable subroutines and APDL code. View full abstract»

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  • Thermal investigation of a battery module for work machines

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2073 KB) |  | HTML iconHTML  

    Thermal Design of Li-ion battery cells/modules is necessary to ensure better cycle lifetime of the batteries. High power batteries (40Ah-100Ah) generate a significant amount of heat which needs to be dissipated somehow. In this work thermal experiments and simulation are utilized for better thermal design of battery module. The results indicate that liquid cooling is almost indispensible for high power battery modules. This methodology also ensures that the waiting period for battery cool down can also be reduced significantly which helps in better and proper utilization of the batteries. View full abstract»

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  • Developing the mesoscale stress-strain curve to failure

    Publication Year: 2011 , Page(s): 1/7 - 7/7
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1532 KB) |  | HTML iconHTML  

    Developing the stress response using the molecular and mesoscale levels is fairly reliable during the initial strain. For instance, modulus is a property that can be established using these techniques and the continuity of scale suggests that both may be used to establish modulus for parameterizing a macroscale model when measured properties are unavailable. However, the latter part of the stress/strain response that helps to establish ties to crack propagation still needs attention. One problem that was previously found was questionable lack of void formation in crosslinked systems due to superficially clean adhesive separation in the simulations. One way to overcome this lack of voiding was to determine how to develop bond breakage criterion that would allow surfaces to develop. This paper discusses development and application of bond breakage, and the impact on the simulated stress/strain curves using mesoscale models. View full abstract»

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  • Evaluation of the change of the residual stress in nano-scale transistors during the deposition and fine patterning processes of thin films

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2139 KB) |  | HTML iconHTML  

    The embedded strain gauges in a PQC-TEG were applied to the measurement of the change of the residual stress in a transistor structure with a 50-nm wide gate during thin film processing. The change of the residual stress was successfully monitored through the process such as the deposition and etching of thin films. In addition, the fluctuation of the process such as the intrinsic stress of thin films and the height and the width of the etched structures was also detected by the statistical analysis of the measured data. The sensitivity of the measurement was 1 MPa and it was validated that the amplitude of the fluctuation exceeded 100 MPa. This technique is also effective for detecting the spatial distribution of the stress in a wafer and its fluctuation among wafers. View full abstract»

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  • Design of athermalized proximity coupled (APC) synthetic green laser opto-electronic package for microprojector displays: Numerical modeling and experiments

    Publication Year: 2011 , Page(s): 1/9 - 9/9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2097 KB) |  | HTML iconHTML  

    Micro-projector based displays are proposed for information display for a number of consumer devices. These displays would provide larger images than existing fixed Liquid crystal displays. The two major components of micro-projector technology are the Light source and the Imaging technology. Three primary colors, red, blue and green are required to create full color images. The light sources in the projection technology would be semiconductor devices that emit these colors. These devices could be either light emitting diodes (LEDs) or lasers. To enable the laser based projection technology, red and blue lasers are commercially available. Native semiconductor green lasers are still in development. As an alternative, synthetic green light can be produced by passing 1060nm infra-red light emitted from a GaAs based semiconductor laser diode (LD) through second harmonic generation (SHG) crystal, thereby emitting the green light at 530 nm. The current research work proposes bringing the SHG structure in close proximity to the LD, thereby eliminating the use of any optics in between. The proximity coupling approach promises to reduce the number of package components and process cost significantly. This paper presents the mechanical package design, coefficient of thermal expansion based displacement estimates, thermal analysis wherein the thermal impedance is predicted and measured, thermo-mechanical analysis wherein the thermo-mechanical stresses and strains are predicted. Shock modeling has been done to understand the displacements of the waveguides during the shock event. Optical modeling is performed to estimate the coupling efficiency change as a function of lateral and longitudinal offset between the LD and SHG waveguides. Finally, an assembled package that generated green light using this design is presented. View full abstract»

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  • Mechanical model of a MEMS inertial rotational gyroscope

    Publication Year: 2011 , Page(s): 1/8 - 8/8
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1768 KB) |  | HTML iconHTML  

    A MEMS inertial rotational gyroscope, able to measure the pitching speed, is presented in the paper. MEMS device normally includes two parts: mechanical and electronic (control system) part. In this paper the attention is focused on the mechanical part to obtain a predictable model that can be integrated with future model of the control system. The model response has been verified via both FEM model and experimental tests. The proposed MEMS gyroscope is made of vibrating masses suspended through micro-beams with respect to the substrate. To increase the sensitivity of the MEMS gyro (i.e. the displacement of the suspended masses), it has been decided to work at low pressure (26 Pa). For this reason, particular attention was paid to identify the parameters associated with the damping. View full abstract»

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  • Mechanical model of a MEMS inertial rotational gyroscope

    Publication Year: 2011 , Page(s): 1/8 - 8/8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2706 KB) |  | HTML iconHTML  

    The verification phase (Final Test) of inertial MEMS gyroscopes design properties takes a basic role in the sensors production. It's during this phase that devices are tested to reveal their effectiveness in the survey of the angular rate. The verification phase is based on a set of several tests able to evaluate the gyroscope characteristic properties, such as the resonance frequency, the quality factor, the quadrature error, and the gyroscope sensitivity. The main goal of the Final Test is to identify characteristic parameters as far as possible in order to save money: actually each gyroscope has to be tested before putting it on the market. The test bench used during the Final Test phase will be proposed as well as a new experimental procedure able to fast identify characteristic parameters. This new testing procedure has been applied both for single-axis and double-axis gyroscopes. The results achieved has been compared with a more accurate (but slower) experimental procedure. View full abstract»

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  • Energy release rate investigation for through silicon vias (TSVs) in 3D IC integration

    Publication Year: 2011 , Page(s): 1/7 - 7/7
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3335 KB) |  | HTML iconHTML  

    The technology of 3D IC integration is highly probable to achieve the demand for high performance, better reliability, miniaturization and lower-priced portable electronic products. Since the through silicon via (TSV) is the heart in 3D IC integration architectures, the reliability issues of TSV interconnects should be extremely concerned. Due to the large thermal expansion mismatch among the Cu, Si, and SiO2, the induced thermal stresses and strains can occur and become the driving forces for failures in TSV interconnects. Hence, the stress analyses and failure mode investigation for TSVs are in urgent need. Among the typical failures, the mostly common failure type is delamination, which will be caused when lower energy release rate (ERR) or higher critical stresses at interfaces are presented. In this study, the finite element modeling (FEM) for a symmetrical single in-line copper filled TSV with redistribution layer is illustrated. Two kinds of horizontal cracks that embedded in the interface of SiO2 passivation and Cu seed layer (Cu pad delamination cases) are introduced to realize the interfacial ERR, where is also the critical stress area that observed from finite element analysis. The significance of design parameters such as crack length, TSV diameter, TSV pitch, depth of TSV, SiO2 thickness and Cu seed layer thickness are also brought up. The methodology of design of experiments (DoE) has been adopted to capture the most important mechanical parameters of the TSV to comprehend the corresponding ERR. It is believed that these results would be helpful to avoid delamination of TSV interconnects in 3D IC integration. View full abstract»

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  • Electrothermal prediction model of Cu low k interconnection on glass substrate

    Publication Year: 2011 , Page(s): 1/5 - 5/5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1328 KB) |  | HTML iconHTML  

    The aim of this work is to determine a joule heating prediction model for thick copper/Low-k interconnects on glass substrate technology. Experiments and simulations have been used to define thermal conductivities of our stack material from thermal resistance study. In a second time, the thermal resistance is used as quantitative response to predict the joule temperature in the strip. The experimental Rthermic results are well fit with a quadratic model which combined with the thermal coefficient of resistance formalism; allow us to define an analytical temperature joule heating formula. This methodology to define an analytical joule heating formula can be widely used to determine the maximum operating conditions and can be implemented in design rules manuals. View full abstract»

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  • Electro-thermal analysis of the Insulated Gate Bipolar Transistor module subjected to power cycling test using specified boundary condition technology

    Publication Year: 2011 , Page(s): 1/5 - 5/5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1232 KB) |  | HTML iconHTML  

    The Insulated Gate Bipolar Transistor (IGBT) module subjected to a power cycle test will induce a heat concentration zone, rapid change of temperature profile and non-uniform temperature distribution on the IGBT chip. The variation of junction temperature can affect the lifetime of the IGBT module. However, the test module contains several components with different scales and material characteristics. As such, it is difficult to analyze the thermal dissipation and temperature distribution of the IGBT chip under power cycle test conditions using conventional finite element modeling technique. A local/global methodology is proposed in this study, in conduction analysis, it only require to construct a local finite element model in conjunction with a set of specified boundary conditions (SBC) where the temperatures are obtained from the computational fluid dynamics (CFD) results, this hybrid modeling technology can make the analysis process easier and more convenient. View full abstract»

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  • Effects of the electrode positions on the dynamical behaviour of electrostatically actuated MEMS resonators

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1409 KB) |  | HTML iconHTML  

    The influence of the lower electrode positions on the dynamic response of polysilicon MEMS resonators is studied and presented in this paper. The change in the frequency response of investigated MEMS resonators as function of the lower electrode positions is measured using a vibrometer analyzer. The decrease in the amplitude and velocity of oscillations if the lower electrode is moved from the beam free-end toward to the beam anchor is experimental monitored. The measurements are performed in ambient conditions in order to characterize the forced-response Q-factor of samples. A decrease of the Q- factor if the lower electrode is moved toward to the beam anchor is experimental determined. Different responses of MEMS resonators may be obtained if the position of the lower electrode is modified. Indeed the resonator stiffness, velocity and amplitude of oscillations are changed. View full abstract»

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  • Investigation of thin films by nanoindentation with doe and numerical methods

    Publication Year: 2011 , Page(s): 1/7 - 7/7
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2655 KB) |  | HTML iconHTML  

    Nanoindentation is one of the most known method for investigating the properties of thin films. The materials can be assessed by means of elastic mechanical properties (hardness and Young's modulus). However, the author's research works show that it is possible to obtain the elastic as well as the plastic material behavior of the investigated thin layer. It can be done by using the nanoindentation experiment and the numerical simulations. This paper focuses then on investigation of thin metal layers by nanoindentation with a support of numerical methods, such as finite element method and numerical optimization processes. Additionally, the 3-level, full factorial design of experiment (DOE) process was applied. In order to carry out such experiment 27 samples were prepared and taken into account: 3 different materials with 3 different thickness's values sputtered on 3 different substrates. The results were then processed by the numerical methods in order to achieve more information about the materials - mainly the plastic behaviour. View full abstract»

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  • Vibration characterization of a MEMS 3D force sensor

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (409 KB) |  | HTML iconHTML  

    MEMS devices and sensors in automotive applications are exposed to vibrations during service life. These vibrations can have a profound effect on the accuracy and reliability of the device. In this study a 3D force sensor, to be used in an automotive tire for the measurement of longitudinal and lateral forces is analysed. The study compromises two parts: First, a numerical analysis is performed to determine Eigen frequencies of the device and a stress strain analysis to determine allowable displacements before the sensor is damaged. Next, Eigen frequencies and mechanical fatigue resistance is evaluated by means of vibration exciter experiments. Additionally, a road test is performed on a test circuit to determine the robustness of the force sensor under actual automotive load conditions while attached to the rims of the wheels. View full abstract»

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  • Comprehensive material characterization and method of its validation by means of FEM simulation

    Publication Year: 2011 , Page(s): 1/8 - 8/8
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2031 KB) |  | HTML iconHTML  

    Numerical simulation plays an important role in product design. Its accuracy relays on a detailed description of geometry, material models, load and boundary conditions. This paper focuses on a new approach of FEM material modeling of three commercially available molding compounds. Curing shrinkage, modulus of elasticity and coefficient of thermal expansion were measured and implemented into commercially available FEM code Ansys. Fringe pattern technique has been used to measure warpage of bimaterial strips. Then FEM simulation of bimaterial strips were done and compared with experimental results. Curing shrinkage has been modeled in an effective way. Its accuracy has been checked on one of the materials by creating bimaterial strips with three different geometrical dimensions, that is varied thickness of mold and copper substrate. View full abstract»

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  • Modelling of metal degradation in power devices under active cycling conditions

    Publication Year: 2011 , Page(s): 1/6 - 6/6
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2280 KB) |  | HTML iconHTML  

    Metal degradation has recently received increased attention as a failure mechanism in power devices under active cycling conditions, i.e. under repeated pulsed voltage/current loads. Both electro-thermal and thermo-mechanical simulation are indispensable for understanding this mechanisms. The paper presents experimental and simulation data for a dedicated test structure. A suitable lifetime model has to go beyond a simple Coffin-Manson type model to capture the essential influencing parameters. View full abstract»

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  • Thermo-mechanical simulations and measurements on high temperature interconnections

    Publication Year: 2011 , Page(s): 1/7 - 7/7
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1671 KB) |  | HTML iconHTML  

    In order to place sensors or electronics in very high temperature environments, new materials and methods for interconnection are required. A comparative study between different electrical interconnection methods for very high operation temperatures (500°C - 800°C) is presented. Thermo-mechanical simulations and characterization of samples of the interconnection types during high temperature exposure are presented. The results of the thermo-mechanical simulations showed that stresses are low in a connection system based on liquid interconnection. This system, however, proved to be difficult to realize due to problems with oxides and sealing of the metallic liquid. Modeling of an interconnection based purely on mechanical pressure without any solder or metallic bond showed high stress. This was also confirmed during high temperature exposure where the connection failed. High stress was also predicted for an interconnection based on nano-Ag paste. The high temperature tests, however, showed promising results at 800°C for over 100 hours. View full abstract»

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  • Lifetime prediction for solder joints with the extended finite element method

    Publication Year: 2011 , Page(s): 1/8 - 8/8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1921 KB) |  | HTML iconHTML  

    Predicting the lifetime of solder joints undergoing thermal cycling is crucial for the electronics industry in order to guarantee a certain performance of their products in the field. Semi-empirical methods are often used to predict the average lifetime of the critical joints. However, to get a reliable failure probability the standard deviation must also be addressed. The deviation of the lifetime from the mean value is a consequence of the variation in microstructure found in actual joints. We therefore propose a new methodology that calculates crack growth based on microstructural features of the joint. A series of random microstructures is generated. Crack growth calculations are performed for each of these structures. The structural problem is solved numerically with the extended finite element method which allows a complete automation of the process. The mean crack length and standard deviation are calculated from the crack growth simulations and the result is compared to experimental data. View full abstract»

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  • Monte Carlo simulation of X-ray diffraction embedded in experimental determination of residual stresses in microsystems

    Publication Year: 2011 , Page(s): 1/7 - 7/7
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1954 KB) |  | HTML iconHTML  

    In this paper a simulation is presented which tracks photons through complex material systems. Besides the usual Compton and Rayleigh scattering that is covered in high energy radiography simulations the presented model considers Bragg-Laue diffraction. The implementation bases on a Monte Carlo code to account for the scattering during radiography. In this paper first results of the simulation are presented. A simple radiation as well as a diffraction experiment was setup. The attenuation coefficient and the position of the diffraction peaks drawn out of the simulation were in good agreement with the literature. View full abstract»

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  • Comparison of metaheuristic algorithms for simulation based OPF computation

    Publication Year: 2011 , Page(s): 1/4 - 4/4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (780 KB) |  | HTML iconHTML  

    Electric power grid operation being an ever challenging scientific field is faced with a high variety of optimization problems. Since the future vision of so called smart grids causes higher complexity and new requirements to these problems, sophisticated investigation in suitable optimization algorithms is essential. Here, metaheuristic optimization strategies are proven to be suitable for high dimensional multimodal problems, and are capable of computing good solutions for hard problems in reasonable time. Therefore, a simulation- based optimization approach is introduced forming a highly applicable framework for testing the suitability of metaheuristic algorithms to practical optimization problems in power grid operation. Different algorithms will be experimentally compared to each other based on Optimal Power Flow computation to the standardized IEEE 30-Bus testcase. View full abstract»

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  • Stress/stain assessment and reliability prediction of through silicon via and trace line structures of 3D packaging

    Publication Year: 2011 , Page(s): 1/5 - 5/5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1424 KB) |  | HTML iconHTML  

    This study assesses the reliability life of 3D chip stacking packaging developed by the Industrial Technology Research Institute (ITRI). The simulation results show that the trends of stress of through silicon via (TSV) structures with different chip stacking numbers are nearly constant during thermal stress analysis. Therefore, the simplified two-layer chip stacking model is adopted to analyze the thermal-mechanical behavior of TSV. Subsequent thermal cycle simulations show that the maximum equivalent plastic strain occurs at the bottom trace near the substrate. The Engelmaier model is selected to predict the fatigue life of TSV, and it shows that the simulation results match experimental results. The effects of the substrate material and underfill are also discussed. TSV structures with BT substrates, which can replace silicon substrates, could effectively protect bottom traces and prevent fractures occurring from copper trace. In addition, when a TSV structure with an underfill is subjected to thermal cycle conditions, chips and vias experience more stress, but copper traces are protected by the underfill. No apparent alteration in reliability performance is detected. View full abstract»

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  • Analytical estimate for cure-induced stresses and warpage in flat packages

    Publication Year: 2011 , Page(s): 1/4 - 4/4
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (545 KB) |  | HTML iconHTML  

    Warpage of flat packages is partly due to chemical shrinkage of the molding compound during cure and partly due to differences in thermal contraction in the subsequent cooling stage. The latter effect is relatively easy to incorporate in numerical simulations but the cure-induced shrinkage effect is not and is therefore often neglected in warpage simulations. Recent validation studies however showed that it is essential that both effects are taken into account. In this paper we develop explicit analytical expressions for the cure-induced residual stresses and warpage of a simple bilayer construction. We do this by assuming that curing always takes place above the molding compounds glass transition temperature such that the material is in its rubbery state and that viscoelastic effects are absent. The analytical warpage model was shown to give results comparable to numerical calculations using a fully cure dependent viscoelastic material model. Furthermore, for the first time accurate analytical expression for the Stress Free Temperature and Stress Free Strain are obtained. With these expressions the effect of cure shrinkage on residual stresses can easily be incorporated in existing (numerical) stress analyses without the need of using extensive cure dependent viscoelastic material models. View full abstract»

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  • Study on passive micro direct methanol fuel cell

    Publication Year: 2011 , Page(s): 1/5 - 5/5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (724 KB) |  | HTML iconHTML  

    In order to overcome the disadvantages of low mass transport efficiency of oxygen to the cathode and poor performance of passive micro direct methanol fuel cells (DMFC), the structures of the cathode current collector for the passive micro DMFC have been studied. The passive micro DMFC employing the cathode current collector with the planar perforated-plate structure has been fabricated. The effect of the anode methanol concentration and the opening area ratio of the cathode on the performance has been investigated. Owing to the influence of contact resistance and oxygen mass transport, the passive micro DMFC exhibits the optimal performance when opening ratio is 50%. Furthermore, the new parallel channels structure of the cathode current collector has been proposed, and the corresponding passive micro DMFC has also been fabricated by utilizing micro precision processing technology. The test results indicate that the mass transfer of oxygen and performance stability have been improved based on the cathode current collector with the parallel channels structure compared to the conventional planar structure. Moreover, a maximum output power density of 9.7 mW/cm2 is achieved. The above studies might be helpful for the developing and application of portable micro power systems. View full abstract»

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  • Research on the failure property of VDMOS device by thermal cycles

    Publication Year: 2011 , Page(s): 1/4 - 4/4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1155 KB) |  | HTML iconHTML  

    VDMOS devices with high voltage and high current are widely used in power semiconductor devices, the microelectronics and power electronics technology. In this paper, the failure properties of VDMOS devices have been investigated by temperature cycling experiment and finite element software simulation. The experiment results show that some electric properties of devices degenerate and there are some cracks on the chip surface after high and low temperature cycling. The main failure mechanism is caused by heat and thermal stress, which have a great impact on the reliability of the devices. In order to study the failure property of VDMOS device under the thermal cycles, a three-dimensional model is established and simulated by ANSYS. The simulation results show that, after applied temperature cycling field, as to thermal expansion mismatching among the components of devices, it will give rise to accumulation plastic strain and stress inner device. The dangerous section of the device is on the interface of chip and adhesive layer. The thickness of substrate and adhesive layer affect heat dissipation of device. The simulation results are in good agreement with experimental ones. View full abstract»

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  • FEA study on electrical interconnects for a power QFN package

    Publication Year: 2011 , Page(s): 1/4 - 4/4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (909 KB) |  | HTML iconHTML  

    This paper presents the results of a numerical analysis on the electrical interconnect options of a Power QFN (PQFN) package, to explore and compare the RDS(ON) performance at DC condition. The modeling involves the PQFN 5mm × 6mm package which initially uses Aluminum wire bonds for interconnection. Competition in the market in terms of better electrical performance packages challenge semiconductor companies to venture into new technology, innovation, process, wafer fabrication, package design changes. For the PQFN, apart from having a thin die with low specific RDS(ON), it is necessary to choose an interconnect which is also electrically efficient. Among the choices aside from the traditional Aluminum round wires are Aluminum ribbon bonding and Cu clip bonding. The comparison is purely based on the electrical performance and the study does not include the cost factors and other material related effects such as stress performance, etc. A commercial FEA code, ANSYS®, is utilized in this study while Solidworks® is used for CAD. View full abstract»

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