Papers by Keyword: Lead Frame

Abstract: Recently, consumers are often dissatisfied with the battery life from even the most advanced lithium-ion rechargeable batteries in mobile phone. A mobile battery was chosen in this study because it is the flat plate of small thin wall which is expected to have some flexing. It is required to be evaluated and designed considering the coupled phenomena. Especially, this paper describes finite element analysis simulation of strength evaluation for epoxy molding compound module using automated FE analysis system.

Abstract: The bending performance of lead frame materials is a very important in improving the quality of lead frame alloys and meeting the needs of high performance integrated circuit. The sringback amount of curvature variation of CuFeP , CuCrZrMg , CuNiSi and CuCrSnZn alloy are researched by numerical simulation. Bending model is built by 3D modeling software, and the necessary post-processing is carried out. The bending springback amount △K of the four kinds of copper alloy materials are calculated out. The results show that the sringback amount of curvature variation of four copper alloys at the same condition from large to small in turn is CuCrZrMg, CuNiSi, CuFeP, CuCrSnZn. Smaller the minimum relatively bending radius of copper alloy used in lead frame, less the springback amount and better the forming performance.

Abstract: As the larger capacity and smaller packaging size are required in the design of a semiconductor, areas and pitches of solder joints have been miniaturized. Therefore the importance of bondability and reliability in soldering technique for the printed circuit board design has been increased since the fatigue failure has been observed at the place between the lead frame and solder joints. To evaluate thermal reliability of SMD type electronic packaging such as SOIC, PLCC and BGA, an exclusive module for modeling a lead frame structure is developed using JavaScript and the thermal stress analysis is performed using ANSYS. A modeling program with GUI can define geometric dimensions of an electronic packaging, assign material properties of a lead frame and a solder and apply boundary conditions. A seamless integration between modeling and analysis is achieved by implementing an interface program to generate an analysis model of a lead frame structure directly from the model information. Heat transfer analysis and stress analysis considering thermal loading are carried out in ANSYS and the results are exploited to estimate the fatigue life of a lead frame based on the S-N curve. The effect of different lead frame materials is examined to identify the mechanical characteristics and the different shapes of the lead frame with same SMD type are investigated to distinguish the reliability.

Abstract: The aging process of lead frame Cu-Cr-Sn-Zn alloy has only been studied empirically by trial-and-error method so far. This paper builds up the prediction model of the aging properties via a supervised artificial neural network(ANN) to model the non-linear relationship between parameters of aging process with respect to hardness and electrical conductivity properties of the alloy. The improved model is developed by the Levenberg- Marquardt training algorithm. The predicted values of the ANN coincide with the tested data. So the ANN system is effective and successful for predicting and analyzing the properties of Cu-Cr-Sn-Zn alloy. The optimized processing parameters are available at 475 C ° -520 C ° aging for 2h-1h.