Abstract
The purpose of this paper is to investigate the effect of inside laminates on residual stress generated in multi-plied copper clad laminates during molding process, which is used widely for printed wiring board. First, a viscoelastic model including not only thermal shrinkage but also plastic deformation is proposed. The generation mechanism of residual stress introduced in the multi-plied copper clad laminates during molding process is qualitatively explained by using this viscoelastic model. Second, the fundamental equations are derived for the residual stress in the multi-plied copper clad laminates considering visco-elastic-plastic deformation. With the fundamental equations, the residual stresses in the multi-plied copper clad laminates with various inside laminates are calculated using each material characteristic. Finally, the residual stresses in the multi-plied copper clad laminates are measured carefully using the layer removal method. Comparing the theoretical and experimental results, the effect of inside laminates on residual stress generated in multi-plied copper clad laminates is discussed.
