Time and temperature dependent mechanical characterization of polyimide materials in electronic packaging application

The thermo-mechanical testing of high performance polyimide films Type HPP-ST supplied by Dupont® is preceded under different strain rate and temperature environment. The stress-strain behavior of materials is simulated with constitutive framework, and the dependence of Young´s modulus on temperature and strain rate is reported . In view of the uncertainty of the Young´s module determination, the specimens were tested with unloading-reloading to verify the test results. Constant strain rate uniaxial tensile test and long-term creep test at various temperatures are preceded to characterize the time-temperature-dependent mechanical property precisely. Cyclic loading test was also performed on the specimen to investigate cyclic stress-strain behaviors. There is no research definitely related in the past, therefore the research is expected to enhance the finite-element-modeling accuracy and characterize the material properties preciously.