Prepreg의 점탄성 특성을 고려한 PCB의 Time-Dependent Warpage 분석 = Time-Dependent Warpage Analysis for PCB Considering Viscoelastic Properties of Prepreg

다국어 초록 (Multilingual Abstract)

In this study, the time-dependent warpage behavior caused by the viscoelastic properties of prepreg in a printed circuit board (PCB) was analyzed by finite element method (FEM). The accurate viscoelastic properties of the prepreg were measured by stress relaxation test, which were then incorporated into constructed warpage analysis model.
When the PCB was subjected to repeated thermal cycles, the warpage of the PCB was restored to its initial state when only the elastic properties of the prepreg were considered, but when the viscoelastic properties were also considered, the warpage was not restored and permanent warpage change occurred. The warpage analysis for three different types of prepreg was conducted to compare their mechanical reliability, and the results showed that materials with elastic properties dominating over viscoelastic properties experienced less warpage, resulting in better mechanical reliability.

참고문헌 (Reference)

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