This paper presents a methodology for TSOP II LOC packaging design. The design objectives are: 1) to optimize mold-flow balance, which in turn minimizes air traps, and 2) to minimize manufacturing variability, which implies optimal quality. A mold-flow simulation tool called C-MOLD is used to evaluate various design configurations. Taguchi’s robust design method is used for manufacturing variability considerations. The simulated results are verified with experimental flow patterns produced by means of “short shots.” In the nomenclature of the Taguchi method, mold-flow balance was chosen as quality characteristics and select a set of design parameters called control factors. The objectives are to find the levels of the control factors, which optimize the flow balance, and, at the same time, minimize the sensitivity of the variations of the control factors.

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