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Accurately predicting warpage using finite element simulation helps accelerate decision-making in the early product development phase. With the ongoing trend of thinning the overall thickness of the microelectronics package as well as its substrate, copper with high modulus and coefficient of thermal expansion becomes more prominent compared to the rest of the non-metallic material. Package warpage...
Equivalent Circuit (EC) method gives a simple alternative method in Frequency Selective Surface (FSS) analyses which are useful for quickly predicting the characteristic of FSS. An impedance modeling of the Equivalent Circuit (EC) for a unit cell of the square loop FSS structure is presented in this paper. The unit cell of the square loop FSS is designed and simulated using the CST Microwave Studio...
Self heating in electrostatically actuated RF MEM capacitive shunt switches is analyzed by coupled electrical and thermal simulations using three-dimensional finite-element analysis. The result shows that despite highly nonuniform current and temperature distributions, the self-heating effect can be approximated by lumped thermal resistances of the switch membrane and the substrate. Additionally,...
This paper presents simulation results of the warpage of single-sided molded packages studied by the finite element method. We calculated the warpage of model packages using elastic and viscoelastic analysis, and discussed the generating mechanism. The amount of the warpage of the single-sided molded package is mainly dominated by two factors. One is the difference of the coefficient of thermal expansion...
Indium bumping is a crucial technology in FPAs (focal plane array) application. In this paper, electroplating method is tried to prepare the indium bump arrays. But one difficulty appears during the reflow process. In such process, many indium bumps fall off from the substrate. To solve such problem, its possible causes are discussed and the corresponding measures are taken. Experimental results show...
In this paper, an effective dielectric permittivity and losses of two-layer substrate for rectangular microstrip patch antenna at THz frequency has been analyzed and simulated in the terahertz frequency regime surveillance system. The proposed antenna has been optimized at 600 GHz frequency by CST Microwave Studio a commercially available simulator based on finite integral technique. To validate the...
In package-on-package (PoP) manufacturing, warpages on both top and bottom packages are concerned. Excess warpage causes solder joint opening, and results in the electrical connection failure of the assembled module. Many parameters of materials, geometry, and process contribute to the warpage of the package. The objective of this paper is to investigate effects of these parameters on the warpage...
After encapsulation, thermo-mechanical deformation builds up within the electronic packages due to coefficient of thermal expansion (CTE) mismatch between the respective materials within the package as it cools to room temperature. Printed circuit boards (PCB) are designed and manufactured with a variety of polyamide materials such as solder mask, metallic material such as copper trace, composite...
We propose a new concept of mounting structure for high- temperature operable power semiconductor devices such as Silicon Carbide (SiC) or Gallium Nitride (GaN) with high reliability. The proposed structure is composed by high purity aluminum (Al) as a circuit metal on substrate and high- temperature resistant joint material as a chip joint layer. In this structure, the circuit metal can deform easily...
This paper presents a pressure sensor based on 2.4 GHz surface acoustic wave (SAW) reflective delay line on a 41deg YX LiNbO3 substrate. Coupling of modes (COM) modeling and finite element method (FEM) were used to extract the optimal design parameters. Based on the simulation results, the SAW device with bar type reflectors was fabricated by electron bean lithography, and characterized wirelessly...
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