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POP stacking technique satisfied the demands of miniaturization, function integration and higher memory space for mobile communication products. However, the warpage of POP package during the soldering procedure will bring the unfavorable effects to quality and reliability of the products. The paper introduces the POP assembling procedure, aims to test and results analysis the effect of package warpage...
Infrared-transparent microheaters have been constructed to reduce the background blackbody radiation produced by the heater. Among other applications, such heaters allow one to probe the high temperature peaks of thermoluminescent(TL) materials. The microheater consists of peripheral platinum heating elements on a mid-infrared transparent alumina platform. Alumina has a relatively low blackbody signal...
Measurements of physical transport properties of thermoelectric materials are plagued by large uncertainties (of tens of percent). Development of new materials towards larger efficiency in converting heat into electrical energy would benefit from improved measurement reliability. We are proposing to extend the 3ω method for the simultaneous measurement of the Seebeck coefficient, electrical conductivity...
This paper describes the dielectric material and the structure of standard capacitors developed by NIM, with capacitance range of 1pF to 1µF and the accuracy of 5ppm to 50ppm at 1 kHz. High stability and high accuracy of standard capacitors mainly derives from a choice of dielectric materials which are fused-silica and nano-ceramic. And the capacitors are placed into a constant temperature control...
This paper addresses the assessment of the performance and efficiency of magnetostrictive harvesters. A suitable test rig is presented, and its characteristics are discussed. Moreover, this work illustrates the harvester parameters able to influence the measurement results. The setup measures the electromechanical energy conversion properties of harvesters, with a relative expanded uncertainty in...
In this paper is presented an apparatus for measurement of thermophysical parameters and control of quality of equipments in high vacuum also in high and low temperature conditions. The equipment gives possibility to explore the measurement dynamics depending on level of temperature and vacuum, also tightness control of joints of materials.
The present work discusses the preliminary results of the proposed indirect porosity measurement methodology. Such methodology makes use of the electrical parameters of Spark Plasma Sintering (SPS) process in order to relate the resistance of a metallic foam sample with its porosity. In order to produce biomimetic orthopedic implants, magnesium foams with open interconnected porosity have been identified...
The move to PWM-based waveforms with substantial high frequency content results in much greater capacitive currents in the stress grading (SG) material and the conductive armor tape (CAT) which increase power dissipation and electric fields within these elements. Treating this subject numerically is challenging for several reasons, viz., (i) the need to measure SG nonlinear properties as a function...
This paper describes an imaging-based approach for the characterization of the pharmaceutical product structures obtained by freeze-drying. The analysis of the dried cake structure and particularly the estimation of its porosity and permeability, is fundamental for the selection of the optimal process conditions and also for the product quality control. Furthermore, the product structure has a dramatic...
Integrating thermal interactions in multimodal systems requires understanding both users sensory abilities and the thermal behaviors of the surrounding environement. Thermal feedback, as a part of haptic feedback can assist in object identification, or in the creation of a more complete haptic signature of a given object. However, the heat exchange occurring between a fingertip and a given touched...
Most carbon nanomaterials are touted for their unusual conductive or semiconductive properties. In this paper, we compare the many-layered graphene oxide (GO) and GO-silver nanocomposite “papers” to elucidate their unusual resistive properties. We have observed significant nonlinearities in resistivity, its dependence on temperature, and current-induced effects on the resistivity of these materials.
Cement rotary kiln is a complex multivariable, large-disturbances and nonlinear system which is full of mass transfer, heat transfer, and physical and chemical reactions. The burning zone temperature (BZT) in cement rotary kiln is a very important production index and has a significant role on the quality of the clinker. However, the BZT is generally difficult to be measured online using the conventional...
In this paper, simulation and optimization of a micro flow sensor is presented. Modeling of the micro flow sensor using ANSYS Fluent for temperature distribution is studied. The detailed structure of the micro flow sensor chip is considered in the simulation model. What's more, the temperature dependencies of physical properties of air are defined to improve the model precision. As a key parameter,...
The influence of viscoelastic behavior of polybutylene terephthalate (PBT) on reliability of the thermal contact of a spotlight module is evaluated. The contact between a module and the heat sink is evaluated using non-linear finite element model. The viscoelastic behavior of PBT was obtained under multiple frequencies from single cantilever DMA experiments. The relevant viscoelastic parameters (i...
POP stacking technique satisfied the demands of miniaturization, function integration and higher memory space for mobile communication products. However, the warpage of POP package during the soldering procedure will bring the unfavorable effects to quality and reliability of the products. The paper introduces the POP assembling procedure, aims to test and results analysis the effect of package warpage...
NiCu is one of the widely used thin-film materials, which is now commonly used as sensor and resistor in very-large-scale-integration (VLSI) because of its high resistivity and stability. However, with the scale decreasing and the temperature increasing in service condition, the limited reliability of NiCu thin-film material has been a key issue in microelectronics and packaging industry mainly due...
Loss angle measurements in ultralow mechanical loss materials are normally affected by a large systematic error due to the excess losses introduced by the suspension system used to hold the samples. Low loss materials are of great interest for ground-based interferometric detcors for gravitational wave observations. Crystals such as sapphire and silicon or amorphous materials such as fused silica...
This paper focuses on the cooling rate of soldering process. Our target was to create a well-controlled equipment that is used to set the adjustable slope of the cooling curve with three special sections. The three sections are: near the melting point, above and below the melting point. The unit uses cooling fans to create a forced convection air flow. K-type thermocouple is used for the temperature...
Consumer electronics such as portable devices (laptops, smartphones) become smaller, thinner and more powerful. In such devices a passive cooling begins to play a dominant role in heat dissipation process. In passive cooling systems thermal resistance of thermal path between semiconductor junction and radiator should be progressively reduced. It can be done by application of efficient (high thermal...
The steady state method is a commonly used and in principle simple way to measure thermal resistance and conductivity of thermal interface materials (TIMs). The sample must be positioned between a hot and a cold plate with constant temperatures, whereby a heat flow through the sample and temperature gradient across the sample are generated. To determine the thermal resistance of the sample the heat...
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