Analysis Of The Structure Evolution And Crack Propagation Of Cu-Filled Tsv After Thermal Shock Test

The effect has been examined of Cu-Filled TSV under thermal shock test. The mismatch in the coefficients of thermal expansion between Cu metal and Silicon generates the thermal mechanical stress. The stress plays critical effect on the performance of the device structure and generates cracks. The Cu metal volume increase and separate from Si matrix after thermal shock test. The Cu metal drift can cause failure issues on the TSV and the cross-section of crack has been observed in the interface between Cu metal and SiO2. The results show that the cracks generate along Cu grains, but irregular Cu grains have an ability to block the crack extension. The Electron Back-scattered Diffraction (EBSD) technique was adopted to characterize the micro-structure of the samples before and after thermal shock test, and the result show that the Cu grains has an indicated growth after thermal shock test.