A practical method for predicting gold-wire deformation during the transfer molding process of semiconductor devices has been developed. In this study, a QFP (Quad Flat Package) having 160 wires was used. The deformed configuration and maximum deformed values were measured for different configurations of the gold wires. Horizontal, dimensionless, and deformed configurations of gold wires could be characterized by elastic straight beams under the conditions of end supports and center load. By combining the results of this study with those of a previous report on the BGA (Ball Grid Array) package, we were able to establish a relationship between the parameter λ and the resin velocity component perpendicular to the center of each wire, resin flow time at the center of each wire, apparent resin viscosity in the mold cavity, gold wire dimensions such as loop height, actual length and diameter, and Young's modulus for the gold wire. The relationship between λ and the maximum horizontal displacement, δ_max was described by a combination of a straight line from the origin of the coordinate axes leading to a saturation curve. For the linear region, an empirical equation model to estimate δ_max was obtained.

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The forming process of a two-layer film is generally constituted by pulling through a variable air gap into a water-cooling bath after the two polymer melts are coextruded through a flat die. In this process, the film thickness often varied in a cyclic manner according to the process conditions. This phenomenon is referred to as draw resonance and is also observed in melt spinning and film processing.
An experimental study was carried out to investigate the draw resonance in forming process of a two-layer film. The two-layer film in which the first layer consists of poly (vinylidene fluoride) (PVDF) and the second layer consists of poly (methyl methacrylate) (PMMA) or PMMA/PVDF was prepared, and the total film thickness was about 50μm. As the take-up velocity or the die land gap was increased and/or the air gap was decreased, the instability of film thickness was in-creased.
The average elongational strain rate was calculated from the conditions of the film forming process. The instability of the film thickness increased abruptly at a critical point of the average strain rate, and the critical point changed with the composition of polymers. Through rheological mesurements on the polymer melts, we concluded that the instability is related to the elasticity of the second polymer layer.

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The material recyclability of shredder dust of car carpets as insulating boards was investigated by using a compression molding method. The shredder dust used here was mainly composed of nylon 6 (NY 6), and polyester (PET) fibers. The shredder dust was heated in a furnace with infrared heaters such that NY 6, having a lower melting point than PET, was solely melted. After the heating process, the shredder dust was compressed, cooled and easily molded into a porous board with low thermal conductivity. The thermal conductivity and bending strength increased with increasing density of molded board. The thermal conductivity increased suddenly when the melted NY 6 connected the neighboring PET fibers. The results suggest that the compression molding method described here shows promise in contributing toward the material recycle of shredder dust of car carpet as insulating boards.

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